HEAT PROCESSING The full spectrum of heat treatment (Vorschau)

International Magazine for Industrial Furnaces 

Heat Treatment & Equipment 

03 I 2013 

ISSN 1611-616X 

Vulkan-Verlag 

All impressions now at: 

www.itps-online.com 

www.heatprocessing-online.com 

9 th - 11 th October 2013 

Wiesbaden, Germany 

Visit us in Hall 9 / Booth 905 

Read all about the 

HEAT TREATMENT CONGRESS 2013 

on pages 33-50 

The full spectrum 

of heat treatment 

B.M.I. Fours Industriels www.bmi-fours.com 

Vacuum Furnaces for hardening, tempering, carburizing, nitriding, 

sintering, high and low temperature brazing 

IVA Industrieöfen GmbH www.iva-online.com 

Retort Type Furnaces, Sealed Quenched Furnaces, Rotary Hearth 

Furnaces, Rotary Drum Type Furnaces, Hood Type Furnaces, Pit 

Type Furnaces 

LOI Thermprocess GmbH www.tenova-loi.de 

Continuous Carburizing Furnaces, Bright Annealing Lines for 

tubes and rods, Heat Treatment Plants for wire 

Mahler GmbH Industrieofenbau www.mahlerofen.de 

Continuous Furnaces with protective gas for bright annealing, 

brazing, hardening, tempering, sintering of powder metal alloys 

RIVA Sp. z.o.o. www.riva-furnaces.com 

Sealed Quench Furnaces, Forging Furnaces, Tempering Furnaces, 

Nitriding Furnaces, Carburizing Furnaces, Endogas Generators 

and Washing Machines 

Schmetz GmbH Vakuumöfen www.schmetz.de 

Vacuum Furnaces for hardening, tempering, brazing, annealing, 

sintering 

HK 2013 

Visit us: 

HärtereiKongress 2013 

October 9-11, Wiesbaden 

Hall 9, Booth 915 

LOI Thermprocess GmbH - Tenova Metals Division 

Am Lichtbogen 29 - 45141 Essen / Germany 

Tel. +49 (0)201 1891.1 - Fax +49 (0)201 1891.321 

loi@tenova.com - www.tenova-loi.de

EDITORIAL 

69 th Heat Treatment Congress 

2013 – Last session in Wiesbaden 

Mer blieve top – dä HK zieht noh Kölle” (Colognian dialect; in 

English: We stay great – the HK moves to Cologne) – with 

this slogan the AWT announced in her latest info flyer the new 

location for 70. Heat Treatment Congress “Härtereikongress” in 

2014. With melancholy many visitors and conference members 

of the “Härtereikolloquium” will look back to the past decades in 

Wiesbaden. Starting in a „small circle“ in the casino of Wiesbaden 

the conference grew to one of the biggest events of heat treatment 

and material science in Europe. The AWT program committee 

has created also this year again a very special conference 

program. In subject fields steel quality, distortion, forging, safety, 

furnace and process technology and control, thermochemical 

heat treatment will be presented in 29 lectures. In addition and 

before beginning the conference the practical orientated “Praktikerseminare” 

will introduce the participants in two lectures 

into induction hardening and energy management systems. HK 

in Wiesbaden 2013 a high-grade event and a “must” for every 

heat treater! 

However, the AWT does not live on the Heat Treatment Congress 

alone. The “innovative engine of the AWT“ are the many 

committees of experts (Fachausschüsse). They initiate and accompany 

suitable research applications and promote the conversion 

of the results into practice issues. Some years ago the “AWT-innovation-certificate” 

was introduced. It appreciates the cooperation 

of AWT members in the committees of experts. Do not forget the 

regional heat treatment circles (Härtereikreise) with their many 

participants and experts in heat treatment. Since decades the 

AWT supports and transfers the exchange and knowledge in 

heat treatment and material science. 

The actual heat processing magazine gives a good introduction 

in the Heat Treatment Congress 2013 and presents new products 

of the heat treatment branch. Microwave heating, optimisation 

of energy efficiency in heat treatment plants and reducing 

of energy consumption in continuous furnace are only a few 

examples of interesting technical articles and product presentations 

in the current issue of heat processing for the “HK”. 

Enjoy being in Wiesbaden this year and reading the latest heat 

processing magazine! 

Dr. Olaf Irretier 

Industrieberatung für Wärmebehandlungstechnik 

IBW Dr. Irretier 

3-2013 heat processing 

1

International Magazine for Industrial Furnaces, 

REPORTS Heat Treatment xxx & Equipment 


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The new web presence of hp 


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2 heat processing 4-2012

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3

TABLE OF CONTENTS 3-2013 

8 56 

HOT SHOTS 

Heat treatment of superlatives 

REPORTS 

Optimisation of energy efficiency 

Reports 

Heat Treatment 

by Jürgen Krail, Klaus Buchner, Herwig Altena 

51 Assessment and optimisation of energy efficiency in heat treatment plants 

by Günter Valder, Herbert Pfeifer 

61 Energy-optimized route from aluminium scrap to extruded semi-finished products 

Microwave Heating 

by Ivan Imenokhoyev, Peter Wübben 

69 Microwave heating – practical examples 

Gas Quality 

by Jörg Leicher, Anne Giese 

73 Changing natural gas qualities: impact on industrial gas-fired applications 

Induction Technology 

by Dirk M. Schibisch, Loϊc de Vathaire 

89 DIN EN ISO 50001 – Opportunities for the international forging industry 


3-2013 TABLE OF CONTENTS 

83 43 

REPORTS 

Increase of inductor lifetime 

HEAT TREATMENT CONGRESS 2013 

All information to the HK 2013 

Measuring & Process Control 

by Albert Book 

97 Temperature measurement in induction heating applications 

Research & Development 

by Ralph Behrend, Marc Hölling, Marco Schünemann, Volker Uhlig 

104 Reducing energy consumption at partial-load operational range on the example of a 

continuous furnace 

HEAT TREATMENT CONGRESS 2013 – SPECIAL 

33 General Information 

34 Basic Data 

36 Program 

40 Product Preview 


5

TABLE OF CONTENTS 3-2013 

92 123 

REPORTS 

DIN EN ISO 50001 – Opportunities for the 

industry 

TECHNOLOGY IN PRACTICE 

Flexible duct burner technology 

News 

10 Trade & Industry 

22 Events 

24 Diary 

30 Personal 

31 Media 

Profile + 

111 Edition 4: Institute of Materials Science – IWT Bremen 

Focus On 

115 Edition 7: Horst Linn 

“Practical experience is very important from the beginning” 

Technology in Practice 

120 Flexible duct burner technology for process air heating 

Companies Profile 

148 Bürkert Fluid Control Systems 


71 116 

INTERVIEW 

FOCUS ON 

hp-Advisory Edition 7: Horst board Linn member received " 

Environmental Award 2011" 

Business Directory 

126 I. Furnaces and plants for industrialheat treatment 

processes 

136 II. Components, equipment, production and 

auxiliary materials 

144 III. Consulting, design, service andengineering 

145 IV. Trade associations, institutes,universities, organisations 

146 V. Exhibition organizers, training and education 

Are you 

playing it 

safe? 

FCU 500 

For monitoring and 

controlling central 

safety functions in 

multiple burner systems 

on industrial furnaces. 

In accordance to EN 746:2010. 

COLUMN 

1 Editorial 

8 Hot Shots 

124 Index of Advertisers 

149 Imprint 

Information about the functional 

safety of thermoprocessing 

equipment can be found here: 

www.k-sil.de 

HK 2013 

HärtereiKongress 

HeatTreatmentCongress 

Stand 6, Foyer OG 

Elster GmbH 

Postfach 2809 

49018 Osnabrück 

T +49 541 1214-0 

F +49 541 1214-370 

info@kromschroeder.com 

www.kromschroeder.com 

3-2013 heat processing

FASZINATION HOT SHOTS 

TECHNIK

Heat treatment of superlatives! 

Forging furnaces for charges up to 500 t with 

integrated residual heat exploitation. 

Source: MIOBA GmbH

NEWS 

Trade & Industry 

TISCO orders an induction furnace system 

from ABP Induction Systems 

TISCO (Taiyuan Iron & Steel Co. Ltd.), one of 

the world’s largest stainless steel suppliers, 

placed an order with ABP Induction Systems 

GmbH, specialist in induction technology, to 

implement high performance induction furnaces 

in their existing steel plant in Taiyuan, 

China. The project has got two phases: The 

installation of two 30 t furnaces with common 

power supply of 24.4 MW for melting of FeCr 

and FeNi (installed and commissioned) and 

the installation of six 65 t furnaces with three 

separate and independent 42 MW power supplies 

for melting of FeCr and FeNi (erection 

start by end of July). 

These induction furnace systems, delivered 

by ABP to TISCO, represent some of the most 

powerful induction furnaces ever designed or 

made in medium frequency converter technology. 

Since June 15 th , 2013 and after successful 

erection of the equipment ABP started 

commissioning of the two 30 t furnaces with 

24,4 MW power supply. Different trials have 

been made during the commissioning phase. 

Mixed carbon steel scrap and pig iron, mixed 

steel scrap and FeCr as well as FeCr and FeMn 

have been charged in the furnaces. 

ABP induction furnaces have fulfilled 

customer requirements by their strong 

stability, high safety as well as operation 

convenience in regard to successfully 

system operating at full 24,4 MW power. 

Remaining true to their principles of delivering 

sustainable technology and environmentally 

friendly systems, ABP’s systems are 

equipped with the up to date EcoTop hood 

for unsurpassed exhaust efficiency during 

charging and melting process. 

Can-Eng Furnaces starts 

up two furnace lines 

Can-Eng Furnaces International Ltd. announced the successful startup 

of two rotary screw hearth bar quench and temper furnace lines. 

The first project – installed in Detroit, Mich. – processes steel bars in 

the range of 1 to 12 inches x 25 feet long at a maximum production 

rate of 25,000 pounds/hour. Each plant layout is a compact U-shape 

design that utilizes regenerative burner technology on the rotary screw 

hearth hardening furnace discharging a single bar at a time into the 

water spray quench system, followed by rotary screw hearth tempering. 

The second project – installed in the greater Chicago metro area 

– processes small-diameter bar in the .750- to 4.00-inch range x 25-foot 

lengths at a maximum production rate of 13,500 lbs/hr. Both systems 

are capable of producing commercially straight bars without the need 

for post-heat treatment straightening and employ Level-II automation 

systems (SCADA). They both came complete with fully automated 

material-handling, debundling and loading systems. The contracts 

were executed for different customers and came on stream in the third 

quarter of 2012 and first quarter of 2013, respectively. 

The furnace systems incorporated the latest in screw hearth 

furnace evolutionary technology, including enhanced screw profile, 

high temperature alloy rail supports, and non-water cooled 

cantilevered roller discharge. The lines represent two of the most 

modern and cost effective fuel fired bar quench and temper lines 

operating in the world today, and allowed the end users the ability 

to bring work back in house that was previously sub-contracted. 

Tenova acquires 

Technometal GmbH 

Tenova announced that it has completed the acquisition of Technometal 

GmbH, a German company based in Duisburg. Technometal 

is a plantmaker with the ability to cover the full set of plants and services 

in secondary metallurgy market: project studies, plant design, engineering, 

supply, commissioning, training and consulting. 

75 % of the steel produced is refined via secondary metallurgy 

processes. Technometal supplies equipment, related to the process 

requirements, with capacities ranging from less than 5 to more than 

300 t. This know-how allows Tenova to integrate and expand its product 

portfolio (LF, VD and VOD) by including the refining equipment for BF/ 

BOF route (RH). 

In this way, Tenova strengthens its position in the field of secondary 

metallurgy with three centres of activities: Tenova Melt Shops (Italy), 

Technometal (Germany) and Tenova Core (USA). 

heatprocessing 

Stay informed and follow us on Twitter 

heat processing 

@heatprocessing 

heat processing is the international magazine for industrial furnaces, 

heat treatment & equipment 

Essen · http://www.heatprocessing-online.com 



NEWS 

Trimet to acquire two aluminium plants in France 

Trimet Aluminium SE, one of Germany’s 

leading aluminium manufacturers, has 

submitted a binding offer to acquire two 

production plants from Rio Tinto Alcan in 

France. With the acquisition of the aluminium 

plants in Saint-Jean-de-Maurienne and Castelsarrasin, 

Trimet contemplates to continue 

its growth strategy and extend its portfolio 

of specialised light metal products. The 

transaction with Rio Tinto Alcan is conditional 

upon the approval of the regulatory authorities 

and the execution of an energy supply 

agreement and a partnership arrangement 

with EDF (Électricité de France). The production 

plants set up by the French aluminium 

manufacturer Pechiney had been taken over 

by Rio Tinto Alcan. The internationally active 

company announced its intention to dispose 

of the sites last year. With a total workforce 

of over 500, the aluminium plants produce 

aluminium wire rod which is used to make 

electric cabling for the energy industry and 

connecting elements for the automobile 

industry, among other things. 

The purchase agreement will secure, 

among other things, the long-term supply 

of aluminium oxide and electric power, key 

requirements for the production of aluminium. 

The energy supplier EDF will take a minority 

stake in the production plants. Trimet hopes 

to develop its successful corporate policy of 

the past few years with the new sites. On this 

transaction, the company was advised by BNP 

Paribas (Guillaume Werner) and for the legal 

aspects by Luther (Dr. Markus Schackmann) 

and Jeantet (Nicolas Goetz). 

Promat High Performance Insulation Division 

offers a comprehensive range of refractory 

and insulating products that is one of the 

most uniquely advanced currently available 

worldwide. 

Using these High Performance Insulation 

products, Promat HPI can provide cost 

effective and energy effi cient state of the 

art thermal management solutions to a 

wide range of challenging markets, and our 

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11

NEWS 


SMS Siemag: Luoyang Wanji grants FAC for two rolling mills 

Following 

the 

smooth and 

efficient commissioning 

of two new 

CVC® plus six-high 

cold rolling mills, 

Chinese aluminium 

producer Luoyang 

Wanji Processing 

Company issued 

the Final Acceptance 

Certificate 

(FAC) for both mills 

to SMS Siemag, 

Germany. 

On cold rolling 

mill No. 1, the first 

strip had already 

been rolled in 2012. 

The FAC was granted before the end of the 

year, marking the successful completion 

of the hot commissioning phase, with the 

rolling mill becoming an integral part of 

production operations. This success was 

repeated on March 30, 2013, when also 

for cold rolling mill 

No. 2 the FAC was 

granted. 

Luoyang Wanji’s 

new production 

facilities in the 

province of Henan 

in East China now 

boast installed production 

capacities 

totaling 260,000 t/a. 

The commissioning 

of these plants is a 

milestone in Luoyang 

Wanji’s entry 

into the production 

of premium aluminium 

cold strip 

in widths of up to 

2,150 mm and final gages of up to 0.1 mm 

for a wide range of applications. 

Taiwanese steelmaker orders pusher furnace from Danieli 

Danieli Centro Combustion S.p.A. was 

awarded a contract for an 80-metricton/hour 

top-fired pusher furnace. The unit 

will be installed at Lo Toun Steel & Iron Works 

Company’s new 600,000-ton/year rebar mill 

complex (low- and medium-carbon steel) 

in Yilan Country, Taiwan. In order to satisfy a 

tight schedule, Danieli Centro Combustion 

will design and manufacture the furnace casing 

using a prefabricated technique based 

on flat modules, which comes supplied lined 

with all the necessary refractory and insulation 

materials. Mixed gas (liquefied petroleum gas 

and air) will be used to generate the required 

heat load. 

Seco/Warwick Europe gets a new order for a vacuum furnace 

for heat treatment of titanium 

Seco/Warwick Europe S.A. have started 

manufacturing of a large unit for 

heat treatment of titanium, model 2.0VP- 

4066/138MHVS, for one of the major aviation 

manufacturers in China. The furnace, which 

will feature a working area of 1,200 x 1,200 

x 3,500 mm, will be equipped with an “all 

metal” heating chamber and a system of 

deep vacuum. The length of the vacuum 

chamber was dictated by the requirement of 

processing a titanium element of an aircraft 

wing. The furnace will be made in accordance 

with the standard AMS2750D class II 

tooling type A. 



NEWS 


13

NEWS 


Co-operation agreement between Otto Junker 

and Can-Eng Furnaces International 

The co-operative agreement between 

Otto Junker GmbH and Can-Eng Furnaces 

International Ltd. has laid the groundwork 

for a further improved, more efficient 

customer service and advisory support. 

Thanks to their complimentary product 

ranges, Otto Junker and Can-Eng will 

enhance each other’s abilities to serve 

world-wide users of thermal processing 

equipment with a complete portfolio of 

melting, pouring, process heating and 

heat treating systems for complex thermal 

processing applications. Moreover, customers 

will thus benefit from comprehensive 

advice and projects implemented in joint 

enterprise. 

To support customers in North America 

including Canada, the two companies 

would invite enquiries for either group’s 

products to be forwarded to the nearest 

geographical sales office. 

Andritz to supply equipment for Tangshan 

Iron and Steel Group, China 

International 

technology 

Group Andritz has 

received an order from 

Tangshan Iron and Steel 

Group, China, to supply 

furnaces and process 

equipment for a hot-dip 

galvanizing plant (annual 

capacity: 415,000 t) and 

a continuous annealing 

line (annual capacity: 

770,000 t). The two new 

heat treatment lines have 

been designed to produce 

high-strength steel grade 

for the automotive industry. 

The order has a value 

of approximately € 50 million. 

Start-up is scheduled for the fourth 

quarter of 2014. 

The furnaces, which form the heart of the 

plant, are fitted with highly efficient low- 

NO X burners. In order to guarantee maximum 

cooling rates, the plant uses the DRJC 

(Differential Rapid Jet Cooling) fast cooling 

system patented by Andritz Metals. DRJC 

sets new standards through highest cooling 

rates with constant and controlled cooling 

across the strip width. In addition, the new 

technology adjusts to the strip width, thus 

helping to save energy. The scope of supply 

also includes automation equipment and 

key process components, such as the zinc 

stripping jet and the shears. Both lines handle 

strip with thicknesses ranging from 0.2 

to 2.5 mm and widths from 700 to 1,600 mm. 

Oerlikon Leybold Vacuum to equip 

state-of-the-art display production line 

well-known East Asian display manufacturer 

has awarded Oerlikon Leybold 

A 

Vacuum the contract to deliver fore-vacuum 

solutions for its state-of-the-art production 

process. This multi-million Swiss Franc contract 

involves fitting the production line with 

around 200 systems. Vacuum systems made 

by Oerlikon Leybold Vacuum are a key element 

in the production of what is currently 

the most innovative display technology, 

AMOLED (Active Matrix Organic Light Emitting 

Diode), which is used in mobile devices 

such as smartphones and tablets. Starting in 

2014, Oerlikon Leybold’s vacuum technology 

will be used in the display manufacturer’s 

standard production for applications including 

vaporization, thin-film wrapping and 

transportation. 



NEWS 

South Steel commissions minimill from SMS Meer 

South Steel in Jizan, Saudi Arabia, has 

commissioned a minimill from SMS 

Meer and SMS Concast. The steelworks 

produces up to 1 million t of billets per 

year, the rolling mill up to 500,000 t of 

rebar. The plant satisfies high demands 

on efficiency, flexibility and productivity. 

The electric arc furnace from SMS Concast 

is equipped with eccentric bottom 

tapping (EBT) and a full platform and is 

designed for 24 charges per day. The ladle 

furnace is used for the secondary metallurgy. 

80 % HBI (hot-briquetted iron) and 

20 % scrap are used as raw material, but the 

furnace can also process up to 100 % HBI. 

The electrode control and process 

automation of the steelworks meet high 

demands, allowing a homogeneous process 

with considerable flexibility and high 

productivity. The continuous caster has 

five strands and can produce 1 million t 

of billets in the formats 130 mm square 

and 150 mm square. Half of the cast billets 

are sold on the regional market, the other 

half is further processed while still hot in 

the rebar mill. 

The rolling mill from SMS Meer is 

equipped with a walking-beam furnace with 

several control zones: The ratio of fuel to air 

is monitored separately in each zone, enabling 

the fuel consumption to be significantly 

reduced. The furnace can be operated flexibly, 

irrespective of the production volume. 

The fully automated rolling mill consists of 16 

housingless stands followed downline by a 

finishing block with six stands. The compact 

design of the HL (HousingLess) roll stands 

and the employment of a finishing block 

ensure compliance with close tolerances. 

Thanks to the HSD® (High-Speed Delivery) 

system, final rolling speeds onto the cooling 

bed of up to 41 m/s are possible. The plant 

can therefore reach a high production rate 

per hour even for small dimensions. 

The South Steel minimill is regarded as 

a milestone in setting up a steel cluster. 

“Jizan Economic City” is one of six newly 

constructed cities with which the Kingdom 

aims to make the Saudi economy 

less dependent on the export of crude 

oil by 2030. 

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15

NEWS 


Elino Industrie-Ofenbau GmbH celebrates 80 th anniversary 

Elino, the industrial furnace manufacturer 

situated in Düren, Germany, has 

gone through a history full of tradition 

with many both political and industrial 

ups and downs, which it all survived successfully. 

Thanks to the intensive research 

and development, a large amount of 

technical innovations were implemented 

in industrial plant technology. Elino has 

established itself a reputation with durable 

and service-oriented furnace plants during 

the last 80 years. In these days the company 

is focusing additionally on energy 

efficiency in plant technology and on the 

subject of renewable energies. 

Elino celebrated its anniversary together 

with many long-standing companions. The 

inauguration of the modernized R&D Centre, 

where customized tests and research 

can be carried out, by Düren´s mayor Paul 

Larue, was the highlight of the jubilee. In his 

speech he praised the stability of the company 

and underlined the fact that Elino plays 

an important 

role in Düren´s 

industry. According 

to him, Elino 

in addition has 

always been 

exemplary also 

with respect to 

the training and 

further qualification 

of young 

people in the 

surroundings. 

Business proprietor, 

Philippe 

Blandinières 

(photo left), 

who integrated 

Elino into his international group of furnace 

manufacturers in 2010, praised the 

commitment of the employees without 

whom the achievements of the last 80 

years would not have been possible. Also 

managing director Dieter Schäufler (photo 

right) believes in “his team” and emphasized 

that companies with such a long history 

have a responsible role to assume not 

only in business but also in society. 

Bodycote awarded transmission 

program 

Bodycote announced that a major OEM awarded a next generation 

of transmission gears to Bodycote Mexico for heat treatment 

and surface enhancement. The family of gears includes sun 

gears, pinion gears and annulus gears. Bodycote will use various 

surface technologies to improve the performance of the transmission 

gears, including low-pressure vacuum carburizing with 

high-speed gas quenching, partial-pressure nitride and precision 

shot peening. In addition, a state-of-the-art gear measurement 

laboratory will quantify dimensional movement during process 

development and long-term production. Bodycote is making a 

significant investment in Mexico to support this new project. 








Air Liquide invests in 

innovative hydrogen 

storage technology 

Air Liquide announces an equity investment in the Australian 

company Hydrexia through its subsidiary Aliad, which 

is dedicated to investments in technology startups. Founded in 

2006 and based in Brisbane, Australia, Hydrexia is a spin-off of 

the University of Queensland. In seven years, the company has 

developed hydrogen storage technology using a new magnesium 

alloy in a solid form called “hydride”. 

The hydrogen storage in the form of magnesium hydrides is 

a technology that has been known since 1975, with its industrialization 

and commercialization being slowed down until now 

because of the high production cost. This new alloy should 

make it possible for the production of fixed or mobile stocks at a 

competitive price compared to existing technologies, combined 

with a higher storage density. This technology is to be used for 

industrial hydrogen markets such as glass, steel and chemicals. In 

concrete terms, Air Liquide could deliver hydrogen stored in the 

form of hydride to its customers rather than in cylinder or bulk. 


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NEWS 



ThyssenKrupp Metallurgical Products acquires 

trading business of BenMet NY 

hyssenKrupp Metallurgical Products GmbH, 

T Essen, has acquired the business of metal commodity 

trading company BenMet NY, headquartered 

in New York, effective July 1, 2013. The companies 

have agreed not to disclose the purchase price. With 

the acquisition, ThyssenKrupp Metallurgical Products 

is expanding its activities in North and South America 

and widening its product portfolio appreciably. 

BenMet trades nonferrous metals and has a similar 

business model to ThyssenKrupp Metallurgical 

Products: Its product range comprises nickel, cobalt, 

cobalt oxide and minor metals and will be supplemented 

by the product portfolio of ThyssenKrupp 

Trumpf: Higher sales 

despite difficult market conditions 

In the 2012/13 fiscal year, ending in June, the 

Trumpf Group generated sales of € 2.35 billion. 

This corresponds to a small increase of 1 % over 

the previous year’s sales of € 2.33 billion. This 

annual sales figure is the highest in the Ditzingen 

company’s 90-year history. 

Orders received at Trumpf during 2012/13 

remained at the previous year’s figure of € 2.33 

Honeywell launches RMG 

gas metering management system 

Honeywell announced the launch of its new RMG 

gas metering management software and service 

solution, which enables natural gas and measuring 

station operators to monitor operations onsite 

or remotely, provide data analysis and facilitate 

remote maintenance. 

The management system supports both RMG by 

Honeywell and third-party measurement devices, 

allowing users to accurately determine the technical 

condition of all gas measurement devices in a 

metering station using a single software package. 

In addition, the ability to remotely access measuring 

devices simplifies planning and organization, and 

Metallurgical Products. BenMet is active mainly on 

the North and South American markets, with a strong 

focus on the USA. The company primarily supplies 

customers in the super alloys sector and the alloying 

and foundry industries. The raw materials are held in 

warehouses in the USA, Mexico and Canada. 

The business activities of the two companies in 

North and South America are to be combined as 

soon as possible. The trading team at BenMet will 

continue under the new ThyssenKrupp ownership 

and Mr. Benham, President of BenMet NY, will continue 

to manage the team through the transition 

period and the next few years. 

billion (after € 2.35 billion in the previous year). As 

far as the result is concerned, Trumpf is expecting 

a lower figure. The company is expecting a pretax 

result lower than that of the previous year. In 

2011/12 Trumpf achieved a pre-tax result of € 211 

million. The final figures are due to be presented 

by Trumpf at the Annual Press Conference on 

October 16, 2013. 

reduces costs as it keeps station visits to a minimum. 

The system employs a framework of gas 

metering management, analysis and terminal 

modules that can be installed without the need 

for customized code changes and are easily 

configured. Dynamic system displays allow for 

detailed schematic diagrams of the monitored 

station, and enable technical and accounting 

personnel to access and act upon current flow, 

pressure and temperature data and alarms in 

real-time. The Honeywell RMG gas metering 

management software will initially be available 

in English and German. 

Versatile. 

09.–11.10.2013 

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Technology

NEWS 


EIB supports the 

construction of 

LNG terminal in 

Lithuania 

The European Investment Bank (EIB) 

is lending € 87 million to Klaipėdos 

Nafta for the construction and operation 

of a new liquefied natural gas (LNG) 

import facility located in the port of 

Klaipėda. This investment is critical for 

Lithuania to diversify and secure its 

energy supply as well as provide backup 

in the event of gas supply failures. 

The LNG terminal comprises a 

floating storage and regasification 

vessel (leased by Klaipėdos Nafta), an 

offshore jetty including gas handling 

facilities and an 18 km pipeline connection 

to the Lithuanian gas grid, 

which are being financed by the EIB 

loan. The project is planned to be 

finalised by the end of 2014. 

Because the EIB promotes security 

and diversification of energy supply it 

particularly welcomes the agreement 

with Klaipėdos Nafta, as the project will 

ensure the sustained supply of a key 

source of energy and will increase competition 

in Lithuania. Lithuanian Minister 

of Energy Jaroslav Neverovič said: "The 

LNG Terminal in Klaipėda is a critical 

component of Lithuania’s energy strategy 

as it is the alternative solution for gas 

diversification in the short term. This EIB 

loan is vitally important for timely construction 

of the necessary infrastructure 

already by the end of next year. It will 

bring transparent competition to the 

gas market, with national and possibly 

regional consumers set to benefit." 

Siemens to supply two Arvedi ESP lines to 

China 

Chinese steel producer placed an 

A order with Siemens Metals Technologies 

for the supply of two Arvedi ESP 

(Endless Strip Production) lines. The energy 

consumption of this type of castingrolling 

facility and the related costs are 

reduced by up to 45 % compared to conventional 

casting and rolling processes. 

This also means a major reduction in CO 2 

emissions. The new plants are designed 

for an annual production capacity of 2 

x 2.6 million t of high-quality, ultra-thin, 

hot-rolled strip products with widths of 

up to 1,600 mm and thicknesses down to 

0.8 mm. Carbon steels, high strength low 

alloyed (HSLA) grades and dual-phase 

steels will be produced. The steel producer 

will receive technical support and 

assistance for plant start-up and operations 

by personnel from the existing ESP 

plant at Acciaieria Arvedi SpA, Italy. These 

casting-rolling facilities will be part of a 

new steelmaking facility currently under 

construction in China. The plant is scheduled 

to go into operation in 2015. 

The order placed for the supply of the 

two Arvedi ESP plants will allow the Chinese 

steel producer to better serve the 

highly attractive local and export markets 

for high-quality, thin-gauge strip products. 

The 180-m-long plants are far more 

compact than conventional casting and 

rolling mills. 

Siemens is responsible for the engineering 

of the Arvedi ESP plants and will 

supply mechanical equipment, mediacontrol 

systems, technological packages 

and automation systems. The entire line is 

controlled by completely integrated basic 

(Level 1) and process optimization (Level 

2) automation, which fully regulate all 

casting and rolling operations. The project 

scope also features a comprehensive 

training and assistance package. This will 

be comprised of theoretical and practical 

training for the customer´s operational 

personnel on the existing ESP plant of 

Acciaieria Arvedi SpA in Cremona, Italy, 

in addition to start-up and operational 

support by specialists from Arvedi. 



NEWS 

Ambrell expands to a larger Netherlands office 

Ambrell, a leading manufacturer of induction 

heating systems, has moved to a 

new office in Hengelo, NL. The company’s 

European office had been based out of Almelo, 

NL, but the company needed more room 

for a high power applications lab, systems 

storage, parts storage and employee offices. 

The new Netherlands office is double the 

size of the previous location. The high power 

applications lab will enable additional applications 

testing with Ambrell’s expanded line 

of high power induction heating systems. 

More warehouse space permits added systems 

and parts storage, which will result in 

shorter lead times for systems and immediate 

turnarounds for new parts. 

The new office also meets the needs of 

the company’s growing base of European 

employees, which has been fueled by 

growth in the European marketplace. The 

added space will benefit customers during 

visits, as they can visit the new high power 

applications lab and have more space to 

meet and discuss their applications. Located 

less than 20 kilometers from Germany, the 

office is convenient for a large number of 

customers and prospects. 

Ipsen sells three vacuum furnaces 

Ipsen shipped three TinyTurbo® units to a 

mid-Atlantic manufacturer. The furnaces 

were 18 inches x 18 inches x 24 inches and are 

equipped to handle a number of processes, 

including hardening, tempering, brazing and 

annealing. Valuable features on the TinyTurbo 

include: fast cooling speeds and distortion 

control (2-, 6- and 12-bar quench-pressure 

options); the ability to meet specific process 

requirements by offering a wide variety of 

hot-zone insulating materials; easy overhaul, 

repair and furnace cleaning with a hydrogen 

10-torr partial-pressure system; and 

decreased cycle times by 25 % with greater 

throughput using convection. 


21

NEWS 

Events 

Aluminium China 2013 global line-up 

celebrates record attendance 

On July 2, Aluminium China, Asia’s leading 

international aluminium exhibition, 

opened its gates to a record breaking 

number of visitors from around the globe 

at the Shanghai New International Expo 

Centre. With an unparalleled line-up of 

top brands, influencers and decision makers 

from 73 countries that represent the 

entire aluminium industry chain, Aluminium 

China 2013 became the strongest edition of 

the show to date, registering double digit 

growth across multiple metrics. 

Introducing a dynamic showcase of 

over 1,000 exhibits on-site this year, displayed 

by 462 exhibitors from China, Asia 

and further abroad, the exhibition attracted 

15,274 unique visitors, an increase of 

28 % over last year. This significant increase 

clearly reflects the potential of Asia’s aluminium 

markets today driven by a large 

number of exhibiting industry giants at 

the show like Conglin, Kobe Steel, Shanghai 

Jieru, Taiyuan Heavy Industry, Novelis, 

Wagstaff, Qatalum and SMS Group. 

Hosting over 460 major manufacturers 

including 121 new exhibitors, Aluminium 

China 2013 covered a massive show floor 

across three halls, Hall W1: premium brands; 

Hall W2: raw materials/semi-finished products 

and Hall W3: machinery and accessories. 

This fresh zoning layout, in combination with 

dynamic sourcing activities, integrated factory 

tours and buyer-seller match-making sessions, 

were part of Reed’s “Source smart” initiative. 

“Source smart” is a novel approach introduced 

to celebrate innovation and stimulate crossborder 

trade that leverages the vast demand 

in China’s growing application industries. 

From show content, one can see that 

China has entered the exciting next phase 

of modern aluminium production with new, 

energy efficient low-carbon furnaces. Furthermore 

its processing companies have 

placed themselves in prime position to satisfy 

global markets with the next generation of 

advanced semi-finished and finished materials 

for numerous application sectors. The 

country has also become a major supplier of 

high-quality lightweight body parts for the 

transportation industry, as well as fenestration 

parts with improved insulation properties. 

Aluminium China 2013 welcomed CEOs 

from major companies and association leaders 

from various booming application sectors 

to explore new product trends in aluminium 

rolling and extrusion: the dominant sectors 

on the show floor. Moreover the ninth presentation 

of the exhibition introduced more 

leading international partners and experts, 

among them top representatives from the 

China Nonferrous Metals Industry Association, 

the International Aluminium Institute, the Gulf 

Aluminium Council, the European Aluminium 

Foil Association (EFA) and a long lineup of corporate 

leaders. 

The trade fair also presented the latest 

advances in Asian aluminium in two new 

dynamic feature areas: downstream processed 

semi-finished products for transportation 

and other key industries; packaging 

products supported by the EFA’s Foil 

Award. Alongside the new feature areas, 

the show also launched the Aluminium 

Downstream Processing Forum, where 

the audience gained insights into the latest 

developments across closely related 

application sectors. The EFA’s display zone 

was also combined with a forum on future 

opportunities for aluminium packaging 

applications in China. 

This year, Aluminium China was again 

collocated with Copper China and Magnesium 

China. The three-events-in-one 

combination amplified business opportunities 

for participants. Furthermore, the 

exhibitions were supplemented by a powerful 

conference program with more than 

20 seminars, workshops and networking 

sessions that included the Automotive 

Light Weight Forum, led by experts from 

automotive aluminium companies; the 

launch of the Aluminium Engineer Club 

- Technical Workshop and the Fenestration 

& Aluminium Extruders Networking 

Cocktail Reception. 

For further information please visit: 

www.aluminiumchina.com 


Events 

NEWS 

European 

Aluminium 

Congress 2013 

is taking place 

in Düsseldorf 

A 

luminium has become an indispensable 

material in motor cars. Castings, structural 

components, semi finished products and 

forgings are now the state of the art for use 

in vehicles. The current discussions regarding 

CO 2 -emissions in particular make the use 

of lightweight materials essential because 

reducing weight using aluminium makes it 

possible to achieve better performance with 

less engine power and thus leads to a reduction 

in CO 2 -emissions. 

At the EAC 2013 with its motto “Aluminium 

Automotive Applications”, the various applications 

of aluminium currently used in cars 

will be presented. The congress will be held 

on 25 to 26 November 2013 at the Maritim 

Hotel in Düsseldorf. During the event potential 

future developments will be outlined that 

will make vehicles of the future even lighter 

and more energy efficient while maintaining 

or even improving today’s safety standards. 

The EAC – European Aluminium Congress 

2013 is aimed at representatives from 

automotive industry, aluminium industry 

and research facilities. Together with representatives 

from the automotive industry, 

manufacturers of semi finished products 

and sub-suppliers, the latest innovative and 

trendsetting solutions will be presented and 

discussed. 

The registration fee amounts to € 950 

per person plus VAT. The fee includes admission 

to all presentations and the exhibition, 

congress documents, refreshments during 

breaks, and an evening meal and lunch as 

shown in the programme. 


www.aluminium-congress.com 

and visit us in Basel at the ILMAC exhibition. 

We are exhibiting! 

ILMAC 

24. - 27.09.2013 

Basel, Switzerland 

Hall 1.0 / E01 


23

NEWS 

Events 

DIARY 

10-12 Sept. EXPOGAZ 

in Paris, France 

www.expogaz-expo.com 

10-12 Sept. Heat Treatment 

in Moscow, Russia 

www.htexporus.com 

12-14 Sept. Aluminium India 2013 

in Mumbai, India 

www.aluminium-india.com 

15-18 Sept. EuroPM 2013 

in Gothenborg, Sweden 

www.epma.com/pm2013 

16-18 Sept. Heat Treat 2013 

in Indianapolis, USA 

www.asminternational.org/content/events/heattreat/ 

16-21 Sept. EMO 

in Hanover, Germany 

www.emo-hannover.de 

17-19 Sept. wire + Tube Southeast Asia 

in Bangkok, Thailand 

www.wire-southeastasia.com 

www.tube-southeastasia.com 

17-19 Sept. Hybrid Expo 2013 

in Stuttgart, Germany 

www.hybrid-expo.com 

25-26 Sept. International Colloquium on Refractories 

in Aachen, Germany 

www.feuerfest-kolloquium.de 

1-3 Oct. Tubotech 2013 

in São Paulo, Brazil 

www.tubotech-online.com 

3-6 Oct. Aluexpo 

in Istanbul, Turkey 

www.aluexpo.com 

7-9 Oct. International Conference on Gears 2013 

in Garching, Germany 

www.vdi-gears.eu 

9-11 Oct. 69 th Heat Treatment Congress 

in Wiesbaden, Germany 

www.hk-awt.de 

15-17 Oct. Pipe & Tube 2013 

in St. Petersburg, Russia 

www.itatube.org 

18-21 Nov. Fabtech 2013 

in Chicago, USA 

www.fabtechexpo.com 

18 th Galvanizing 

& Coil Coating 

Conference in Munich 

Returning for its 18 th year, Metal Bulletin’s Galvanizing 

and Coil Coating Conference is coming on 

10 to 11 September 2013 to the automotive hub 

of Munich. Featuring a panel of expert speakers 

from across the supply chain and unrivalled 

networking opportunities this event is not to 

be missed. 

Despite a challenging period for European 

steel producers the global market for galvanized 

and coated steel is witnessing unprecedented 

growth. Whilst there are concerns of a slowing 

Chinese economy, South East Asia is witnessing a 

huge surge in automotive and consumer goods 

demand. A similar rate of growth is emerging in 

MENA. It is now more important than ever to 

identify and take advantage of the opportunities 

these growing markets offer. These vital industry 

issues and more will be discussed by senior level 

executives at this year’s must attend event. This 

conference will ensure you have the correct business 

strategies to succeed, remain competitive 

and maximise profit. 

The conference is a global forum for traders, 

steel mills, coil producers, steel service centres, 

technology & equipment suppliers, raw materials 

suppliers an end users. The topics planned to be 

discussed are amongst others: 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

Market fundamentals for galvanized and 

coated steel globally – where is the industry 

heading? 

developments in the white goods sector 

and the impact on steel producers, 

changing requirements of automotive 

manufacturers – latest developments in 

high-strength low-alloy steels, 

challenges facing steel service centres in 

times of economic uncertainty, 

addressing structural overcapacity in the 

European market, 

coated steel trends in the construction 

sector, and 

■■ 

new developments in coatings – 

increasing popularity of Zn-Al-Mg. 


www.metalbulletin.com/events/galv13 


Events 

NEWS 

EMO Hannover 2013 – 

Metalworking sector showcases its capabilities 

The EMO Hannover will be opening its 

doors from 16 to 21 September 2013. 

At one of the world’s premier trade fairs 

for the metalworking sector, international 

manufacturers of production technology 

will under the keynote theme of “Intelligence 

in Production” be showcasing their 

products, solutions and services relating to 

metal as a material. 

By the end of June, around 2,030 companies 

had registered. On a net exhibition 

area of over 177,600 m 2 , they will be showing 

the international trade visitors how they can 

best meet and master the challenges they 

face in the production process. 

60 % of the exhibitors don’t come from 

Germany, but from 39 other countries of the 

planet. Reflecting its leading status in terms 

of technology, Europe, with more than 1,500 

exhibitors, is the most heavily represented 

region. Around a fifth, more than 430 firms, 

however, are arriving from Asia alone. 

For the EMO Hannover 2013, as one of 

the world’s premier trade fairs for the metalworking 

sector, the international macro-economic 

environment plays an important role. 

This year, economic pundits are predicting 

another rise in machine tool consumption, 

of 2 %, to a record volume of what will 

then be around € 68 billion. This means that 

following three strong preceding years, we 

are seeing an incipient temporary slowdown, 

resulting primarily from continuing 

loss of confidence in the prospects of the 

global economy. Economic pundits anticipate, 

however, that GDP and industrial 

production output will gain significantly in 

momentum during the second half of 2013. 

Machine tool consumption is accordingly set 

to grow by one tenth in 2014. 

The success of the EMO Hannover, as the 

world’s premier trade fair for this sector, is 

significantly underpinned by the globalised 

nature of the machine tool business. More 

than half of global machine tool production 

output is internationally traded. The volume 

has risen by 80 % since the turn of the millennium. 

This applies even more cogently 

for Europe’s machine tool industry, which 

exports almost 85 % of its production output. 

According to an analysis prepared by 

the European Association of the Machine 

Tool Industries (CECIMO), moreover, more 

than 80 % of its exports involving metal-cutting 

machine tools feature NC technology. In 

the USA’s machine tool industry, the figure is 

a mere 61 %, while in China’s corresponding 

sector it’s an even more modest 44 %. 

Germany, the host country of the EMO 

Hannover 2013, ranks among the major 

players on the international machine tool 

scene. Not only will the Germans, who will 

be providing the largest number of exhibitors, 

with more than 800 companies, be a 

major presence at the fair; as the secondbiggest 

exporter and fourth-largest market, 

Germany is also a heavyweight when it 

comes to research and development work in 

the global machine tool industry. Last year, 

German manufacturers produced machines 

worth € 14.2 billion. This corresponded to 

growth of 10 %, the best result among the 

five biggest producer nations. The pre-crisis 

level of 2008 has thus been reached again, 

too. In the ongoing year, German manufacturers, 

like their international counterparts, 

are focusing on consolidation. The forecast 

is for modest growth of 1 %. This trend is 

once again being fuelled by exports, which 

at around € 9.6 billion with an export ratio of 

73 % are already running at a record level. 

Here, too, modest growth of one cent is 

being predicted for the current year. 

So all eyes are focused on what’s going to 

happen in the months ahead. Order bookings 

from abroad are perceptibly stabilising. 

While export orders for German machine 

tools fell by 18 % during the year’s first quarter, 

the drop had shrunk to a mere 8 % in the 

year’s first five months up to May. Experience 

has shown that this will be followed by a 

consolidation in domestic orders after a time 

lag of several months. 

The investment plans of Germany’s 

major customer groupings also give persuasive 

grounds for a more optimistic 

assessment. Though in the current year 

growth of only 1.7 % is being forecast, the 

figure predicted for 2014 is set to exceed 

7 % again. Encouraging signals are also 

coming from the Ifo business climate 

index in the capital goods industry. Expectations 

for future business developments 

have been indicating an uptrend until 

June of this year. Against this background, 

the VDW (German Machine Tool Builders’ 

Association) expects that orders for 

machine tools will receive further impetus 

from the EMO Hannover. Order trends in 

the past show that this has regularly been 

the case after an EMO Hannover. 



+++ www.heatprocessing-online.com +++ www.heatprocessing-online.com +++ www.heatprocessing-online 


25

NEWS 

Events 

wire & Tube Southeast Asia 2014 in Bangkok 

Southeast Asia’s leading regional trade 

fairs for the synergistic wire and tube 

industries that have long since built a reputation 

on the international level will be 

staged from 17 to 19 September 2013 at 

the Bangkok International Trade & Exhibition 

Centre (BITEC) in Bangkok, Thailand. 

Organized by Messe Düsseldorf Asia, over 

300 companies will be exhibiting at both 

wire and Tube Southeast Asia during the 

three-day event. The two trade fairs will 

showcase innovations and trends on highperforming 

machinery, processing and 

automation in the wire, cable, tube and 

pipe industry in Southeast Asia. 

Recognised as the industries’ muchawaited 

trade fairs for the region, wire and 

Tube Southeast Asia 2013 will outperform 

its successful edition in 2011 with higher 

profile exhibitors from big international 

companies, approximately 15 % of whom 

are first-time exhibitors. Over 40 % of 

international exhibitor participation are 

from Europe. There will also be an impressive 

representation from market leaders 

from around the region. Seven national 

pavilions and country groups from Austria, 

China, Germany, Italy, Singapore, Taiwan 

and the USA have secured participation 

to the trade fairs. 

Southeast Asia remains resilient amidst 

persistent global economic uncertainty, 

projecting an average annual growth rate 

of 5.5 % over the next five years to 2017. 

This signals that trade fairs continue to fulfil 

the industries’ needs as an international 

business conduit into the region. The 

region is increasingly becoming a manufacturing 

and 

industrial hub 

for many global 

companies seeking 

to locate and 

keep in touch with 

available business 

opportunities. 

According to 

Global Industry 

Analysts, the 

global market for 

seamless pipes 

and tubes is projected to reach 113.8 million 

t by 2018. In addition, the global market 

for spiral welded pipes and tubes is 

projected to reach 24.6 million t by 2018, 

driven by economic recovery, increase in 

activity in the energy sector and growing 

pipeline construction projects. Industry 

reports indicate that the Asia-Pacific 

region represents the largest market 

worldwide, driven primarily by increased 

use in transporting natural gas. Similarly, 

business opportunities in the wire and 

cable industries are estimated to contribute 

approximately 3 % of the world’s production 

of wire and cable. 

This year’s trade fairs will see a comprehensive 

display of products and services 

aimed particularly at enhancing productivity 

and operations, as well as cost-effective 

solutions. The wire Southeast Asia trade 

fair is supported by numerous prominent 

industry associations that include IWCEA 

(International Wire and Cable Exhibitors’ 

Association), International Wire and 

Machinery Association, ACIMAF (Italian 

Wire Machinery Manufacturer’s Association), 

Iron and Steel Institute of Thailand, 

and many others. Thailand’s largest trade 

fair for the wire and cable industry is all 

about machinery and equipment, materials 

trends and accessories used for making 

all types of wire and cable, and innovative 

solutions for the wire and cable sector. 

Trade visitors can expect to see a wide 

range of wire, cable, tube and pipe products 

for the building, electronic, power, 

and telecommunications sector as well as 

data wire and cable, and other insulated 

wires and cables. 

In addition, visitors will also be able to 

attend a series of seminars and training 

courses at wire and Tube Southeast Asia 

2013 as well as other offerings which have 

been organized to provide added value 

to the exhibition and maintain its leading 

position in the industry. 


www.wire-southeastasia.com 

www.tube-southeastasia.com 

HOTLINE Meet the team 

Managing Editor: Dipl.-Ing. Stephan Schalm +49(0)201/82002-12 s.schalm@vulkan-verlag.de 

Editorial Office: Annamaria Frömgen +49(0)201/82002-91 a.froemgen@vulkan-verlag.de 

Editor: Thomas Schneidewind +49(0)201/82002-36 t.schneidewind@vulkan-verlag.de 

Editor (Trainee): Sabrina Finke +49(0)201/82002-15 s.finke@vulkan-verlag.de 

Advertising Sales: Bettina Schwarzer-Hahn +49(0)201/82002-24 b.schwarzer-hahn@vulkan-verlag.de 

Subscription: Martina Grimm +49(0)931/41704-13 mgrimm@datam-services.de 


Events 

NEWS 


27

NEWS 

Events 

ITPS 2013: excellent feedback about the Thermprocess Summit 

ITPS – International Thermprocess Summit 

– proved to be a great success when 

it was held for the first time in Düsseldorf 

on 9 and 10 July 2013. Positive feedback 

has been received not only from the 147 

international participants from 16 different 

countries but also from the companies 

that exhibited. Experts from all over the 

world, e.g. from Brazil, China, India, Japan 

or the USA, considered it worthwhile making 

the trip to attend the two-day Thermprocess 

Summit, where the latest technologies 

and processes in the heat treatment 

industry were presented – followed by 

in some cases heated discussions. René 

Branders, President of the European Committee 

of Industrial Furnace and Heating 

Equipment Associations (CECOF) in Brussels, 

for example, drew attention in a tweet 

sent directly from the conference to the 

“outstanding debates” that were being 

held in Düsseldorf. 

The conclusions drawn by the “Gold” 

and “Silver” sponsors of ITPS 2013 were 

positive, too. Dr Hermann Stumpp (LOI 

Italimpianti, Tenova Iron and Steel): “Our 

industry – furnace manufacturing – is 

very aware of energy consumption issues, 

because we have been confronted with 

them for a long time now. The first day of 

ITPS made it particularly clear to us what 

exacting demands the industry can expect 

to face in future. This conference plays an 

important networking role in this context.” 

Dr Andreas Seitzer found the second 

day of the event even more dynamic than 

the first. The director of SMS Elotherm 

reports: “We were impressed by the wide 

range covered by the presentations – from 

macroeconomic questions to global marketing 

strategies. We think that the concept 

adopted by ITPS, involving eminent 

speakers interacting with top companies 

in the industry, is very effective. A followup 

event is definitely welcome”. 

The director of the induction furnace 

manufacturer ABP Induction Systems, Dr 

Wolfgang Andree, was more measured in 

INTERNATIONAL 

THERM 

PROCESS 

SUMMIT 

his review of the first ITPS: “I consider it to 

be very positive that ITPS has been initiated; 

now we need to analyse this first conference 

and make minor improvements. 

Then it will be a thoroughly successful 

event in future, too.” 

The vice president for heat treatment 

equipment at the Seco Warwick Group, 

Thomas Kreuzaler, emphasises that ITPS 

was a very successful event with excellent 

networking opportunities that was 

a neutral forum for observing how business 

is developing in the thermprocess 

technology field. 

The organisers of ITPS 2013 were 

delighted about the successful premiere 

at the end of the second day of the conference. 

Messe Düsseldorf director Joachim 

Schäfer summarises his entirely positive 

impressions as follows: “The first ITPS was 

just as successful as we had hoped beforehand. 

Participants and exhibitors used the 

conference as a welcome opportunity to 

hold in-depth exchanges of ideas and 

information between two THERMPROCESS 

trade fairs.” For the director of the VDMA 

thermprocess technology trade association, 

Dr Timo Würz, ITPS was a great 

success: “There is obvious demand in the 

industry for intensive debate about the 

issues that will have to be tackled in future 

and ITPS met this need in every respect 

at its premiere”. Jürgen Franke, director of 

Vulkan Verlag required just one word to 

describe his feelings about ITPS: “Fabulous!” 

The ITPS conference is part of the 

established Bright World of Metals event, 

that will be inviting the industry community 

to come to Düsseldorf again for its 

trade fairs GIFA, METEC, THERMPROCESS 

and NEWCAST from 16. to 20. June 2015. 

For further information and a big choice of 

photos of the event please visit: 




Events NEWS 

Hannover Messe 2014 

Overview of dates 

and program 

In 2014 (7 to 11 April) all the trade shows under 

the Hannover Messe umbrella will focus on key 

current issues – for example, the networking of 

industrial processes across existing technological 

and corporate boundaries. 

The core display categories at Hannover Messe 

2014 are industrial automation and IT, energy and 

environmental technologies, industrial supply, production 

engineering and services and research 

and development. 

After Hannover Messe 2013, it is of course time 

for Hannover Messe 2014 and 2015. About 1,000 

exhibitors already took advantage of the attractive 

rebooking offer in April 2013 to save 14 €/m 2 . More 

than 600 companies have registered for Hannover 

Messe 2014, and about 300 companies for Hannover 

Messe 2015. 

Those who missed 

out on the rebooking 

offer can still 

benefit from the 

early booking rate 

until 15 September 

2013. Until this date 

the basic charge 

for indoor space is 

reduced to 197 €/ 

m 2 and for openair site to 75 €/m 2 . After 15 September 

the price per m 2 amounts to 204 or rather 79 €. 

At www.obs.messe.de those who are interested can 

book their participation for the upcoming Hannover 

Messe 2014 as well as for 2015. 


www.hannovermesse.de 








heat processing is published by Vulkan-Verlag GmbH, Huyssenallee 52-56, 45128 Essen, Germany 

The international magazine 

for industrial furnaces, 

heat treatment plants 

and equipment 

The technical journal for the entire field of industrial furnace 

and heat treatment engineering, thermal plants, 

systems and processes. The publication delivers comprehensive 

information, in full technical detail, on developments 

and solutions in thermal process engineering for 

industrial applications. 

Make up your mind on how to subscribe! 

· The printed volume suits the classic way of reading. 

· The e-paper issue offers the modern way of receiving 

informationon a computer, tablet pc or smart phone. 

· The printed volume + e-paper issue combine the best 

of both worlds. 


knowledge for The 

fuTure 

29

NEWS 

Personal 

Siemens: Joe Kaeser new President and CEO 

Joe Kaeser (56), 

Chief Financial 

Officer (CFO) 

of Siemens AG 

since 2006, is 

the new President 

and CEO 

of Siemens 

AG, effective 

August 1, 2013. 

A new CFO will 

be appointed very shortly. The Supervisory 

Board looks back on Peter Löscher’s 

achievements as President and CEO of Siemens 

AG with great respect. Peter Löscher 

will continue to assist the company in the 

processing of open topics until September 

30, 2013. He will also remain associated 

with Siemens AG and perform a number 

of duties – for example, chairing the Board 

of Trustees of the Siemens Stiftung – at the 

request and in the interest of the company. 

Joe Kaeser pointed out that Siemens has 

been too preoccupied with itselve lately 

and have lost some of its profit momentum 

vis-à-vis competitors. His declared aim 

is to put Siemens back on an even keel and 

create a high-performance team. By the 

autumn, the Siemens team will provide 

information on the further refinement of 

the company program and address the 

medium-term prospects and the vision 

for the company. 

SMS Group: Changes in the Supervisory Board 

With effect from July 1, 2013, Heinrich 

Weiss (photo), who has been responsible 

for the development and leadership of 

the group of companies for the last 45 years, 

was resigned from his post on the Managing 

Board and assumed the Chairmanship of the 

Supervisory Board. 

The former Chairman, Dr. Manfred 

Bischoff, retains his commitment to the 

company as a Member of the Supervisory 

Board. Dr. Joachim Schönbeck, who is 

already a Member of the Managing Board, 

was appointed to represent the Company 

externally with effect from July 1, 2013. 

Jointly with his colleagues, Burkhard Dahmen 

and Eckhard Schulte, he continues to 

constitute the Management of SMS GmbH. 

Dr. Joachim Schönbeck is primarily 

responsible for SMS Meer as before, 

Burkhard Dahmen is responsible for SMS 

Siemag and Eckhard Schulte is the CFO 

of the group. 

Vincenzo Ferri is leading 

CICOF 

The new President of CICOF, the Italian Committee 

of industrial furnace manufacturers has been 

appointed for the biennium 2013-2014. He is Vincenzo 

Ferri (Cimprogetti SpA, Dalmine, Bergamo). He succeeds 

to Michele Bendotti, to whom CICOF’s appreciation 

is addressed owing to his active contribution as 

president of the association. In his own activity, Vincenzo 

Ferri will be supported by two Vice Presidents: 

Michele Bendotti (Forni Industriali Bendotti SpA) and 

Enrico Marranini (I.C.M.I. Srl). 

Egbert Baake new 

UIE president 

Prof. Dr.-Ing. Egbert Baake is the new president of the UIE International 

Union for Electricity Applications. Dr. Baake succeeds 

Prof. Dr.-Ing. Ronnie Belmans, the UIE’s long-standing president. 

The 53-year-old is Professor and Academic Director of the Institute 

of Electrotechnology at the Leibniz University of Hannover, 

and has been an active contributor within the UIE since as early as 

1998. He was appointed chairman of UIE Working Group 3, Education, 

Research & Dissemination of Knowledge, in 2008. The UIE 

was founded in 1901 and has its headquarters in Paris. Its global 

membership includes energy-supply utilities, industrial corporations, 

electrical-energy technology associations and organisations, and 

also representatives from research, teaching and theory. 


EEA Report No 6/2013 

ISSN 1725-9177 

Media 

NEWS 

EEA Study: Bioenergy production must 

use resources more efficiently 

Using biomass for energy is an important 

part of the renewable energy mix. However, 

bioenergy production should follow EU 

resource efficiency principles, according to a 

new report from the European Environment 

Agency (EEA). This means extracting more 

energy from the same material input, and 

avoiding negative environmental effects 

potentially caused by bioenergy production. 

The report, “EU bioenergy potential from 

a resource efficiency perspective”, primarily 

looks at the potential for energy from agricultural 

land, although it includes forest and 

waste biomass in the overall analysis. 

Building on previous analysis, the report 

shows that the current energy crop mix 

is not favourable to the environment. It 

re commends a broader mix of crops to 

reduce environmental impacts. Specifically, 

this should include perennial crops, which are 

not harvested annually – for example energy 

grasses or short rotation willow plantations. 

This would enhance, rather than harm, ‘ecosystem 

services’ provided by farmland – such 

as flood prevention and water filtration. 

The report develops three different ‘storylines’ 

with varying technological, economic 

and policy assumptions. This helps 

explore different future options, illustrating 

which bioenergy types are most resourceefficient 

and which have the lowest environmental 

impact. 

INFO 

by European Environment 

Agency (EEA) 

July 2013, 64 pages 

www.eea.europa.eu 

EU bioenergy potential from a 

resource-efficiency perspective 


31

NEWS 

Media 

INFO 

by Christoph Schmitz 

2 nd edition 2013 

approx. 500 pages, 

hardcover 

€ 130.00 

ISBN: 978-3-8027-2970-6 

www.vulkan-verlag.de 

Handbook of Aluminium Recycling 

The Handbook has proven to be helpful to 

plant designers and operators for engineering 

and production of aluminium recycling 

plants. The book deals with aluminium 

as material and its recovery from bauxite, 

the various process steps and procedures, 

melting and casting plants, metal treatment 

facilities, provisions and equipment for environmental 

control and workforce safety, cold 

and hot recycling of aluminium including 

scrap preparation and remelting, operation 

and plant management. Due to more 

and more stringent regulations for environmental 

control and fuel efficiency as well as 

quality requirements sections about salt slag 

recycling, oxy-fuel heating and heat treatment 

processes are now incorporated in 

the new edition. The reader is thus provided 

with a detailed overview of the technology 

of aluminium recycling. 

INFO 

by EPMA 

www.epma.com 

European Powder Metallurgy Association 

launches new website 

After over six months of development 

work the EPMA launched a new website. 

The new EPMA website went live on the 10 th 

June. The newly designed EPMA website is 

underpinned by a Joomla! system enabling 

the content and services to be added more 

freely than the previous version. 

The new EPMA website has carried over a 

great deal of existing content from the previous 

version, making it one of the most comprehensive 

resources of Powder Metallurgy 

related information on the internet. A range of 

new services for members and non-members 

is under development along with a rolling programme 

of updating the Powder Metallurgy 

Case Studies through the Spotlight in PM programme, 

to ensure the new site is current and 

relevant to end-users. 

Erwin Dötsch 

Inductive Melting 

and Holding 

Fundamentals | Plants and Furnaces | Process Engineering 

2. Edition 

INFO 

by Erwin Dötsch 

2 nd edition 2013 

approx. 300 pages, 

hardcover 

€ 75.00 

ISBN: 978-3-8027-2386-5 


Inductive Melting and Holding 

The second, revised edition of this standard 

work for engineers, technicians and 

other practitioners working in melting shops 

and foundries is to appear in September 

2013. This new version of the title on inductive 

melting and temperature maintenance 

originally published in 2009 is the result of 

the great demand generated at that time, 

and includes coverage of the plant- and 

process-engineering advances achieved 

during the intervening four years. These 

relate, in particular, to the use of the induction 

furnace in electric-steel production, 

a field in which this environmentally and 

mains-friendly melting system has evolved 

into a genuine and advantageous alternative 

to the electric arc furnace. Characteristic of 

this is the recent increase in inverter supply 

power from its maximum of 18 MW at the 

time of publication of the first edition of the 

book to its present 42 MW to permit supply 

of 65 t crucible furnaces. 


GENERAL INFORMATION 

Heat Treatment Congress 2013 

The Association for Heat Treatment and Materials 

Technology (AWT) organizes the 69 th Heat Treatment 

Congress (HK) on heat treatment, materials technology, 

production technology, and process engineering from 

October 9 to 11, 2013 in the Rhein-Main-Hallen Wiesbaden. 

This year again, more than 600 participants from industry, 

research, and teaching are expected to participate in this 

trade congress. In 30 technical lectures and a parallel technical 

exhibition they can get information on the state-ofthe-art 

technology and future developments in the fields 

of heat treatment, materials, production technology, and 

process engineering. For practitioners in particular, four 

principle-oriented survey lectures as well as two practitioners’ 

seminars are provided. Thus, the HK 2013 is once again 

a unique platform for innovation, knowledge transfer, and 

exchange of experience. The survey lectures are geared 

towards the announced HK main topics: 

■ Process monitoring and product quality, 

■ heat treatment systems engineering, 

■ heat treatment safety engineering and 

■ steel quality. 

Karl-Michael Winter (Process Electronic GmbH) will talk 

about “Process monitoring and control in the course of 

time”. The topic heat treatment systems will be presented 

by Dr. Olaf Irretier (IBW Dr. Olaf Irretier) in a presentation 

titled “Overview and developments of industrial furnace 

technology for heat treatment of metals”. Frank Treptow 

(Aichelin GmbH) will discuss “Safety aspects in heat treatment” 

and Dr. Christian Günther (Saarstahl AG) will address 

the issue “Increasing product demands – from the steel 

making point of view”. 

A special highlight will be the plenary lecture “Living 

prototypes: Innovations from nature” by Prof. Antonia B. 

Kesel (Bionik-Innovations-Centrum Hochschule Bremen) 

on the morning of October 10. As last year, there will be a 

simultaneous interpretation from German to English and 

vice versa for the main congress event. In this way AWT 

creates a forum for international knowledge transfer. This 

also addresses a significantly increased demand on the part 

of foreign visitors who, in the past, could only participate in 

the exhibition. Furthermore, the exhibitors of the HK can 

get a price-reduced, transferrable entrance ticket for the 

complete event in order to enable their employees to get 

further training during the event. Shortly before the HK, 

the AWT will publish a new program as congress magazine 

with many additional categories. It will combine the 

information on the congress program with the abstracts in 

two languages and provide the current hall plans and the 

list of exhibitors. A trade directory will make route guidance 

through the exhibition easier. In addition, the magazine will 

also be an edition of the AWT-Info. This means that the AWT 

members receive detailed information on the HK and the 

visitors of the HK will receive the same detailed information 

on the activities and events of the AWT. Furthermore, 

the exhibitors publish product presentations and reports 

from the industrial practice in a separate category of the 

magazine. You will find the HK as an individual website with 

all information on the congress and the exhibition on the 

internet at the address: www.hk-awt.de 



33

BASIC DATA 


Heat 

Treatment 

Congress 2013 

Basic Data 

Location 

Rhein-Main-Hallen Wiesbaden 

Rheinstraße 20 

65185 Wiesbaden / Germany 

Organizer 

Arbeitsgemeinschaft Wärmebehandlung 

und Werkstofftechnik e.V. 

Paul-Feller-Straße 1 

28199 Bremen / Germany 

Tel: +49 421 / 5229339 

Fax: +49 421 / 5229041 

E-Mail: info@awt-online.org 

Internet: www.awt-online.org 

Opening hours 

Wednesday, 09 October 2013, 8:30 - 18:00 h 

Thursday, 10 October 2013, 8:30 - 17:00 h 

Friday, 11 October 2013, 8:30 - 14:00 h 

Fees 

Complete program: 690 € 

University employees and speakers: 385 € 

1-day-ticket: 460 € 

2-days-ticket: 575 € 

Transferrable ticket for exhibitors: 320 € 

■ 

Practitioners’ seminar (only in German language) 

One seminar: 150 € 

Both seminars: 290 € 

Payment 

The amount is due by bank transfer after receipt of the 

invoice. Checks won’t be accepted. When booking onsite 

you can pay by Master Card, Visa Card or cash. Tickets 

will be sent after receipt of payment until 25 September. 

The program magazine will be handed out on-site. After 

deadline tickets also will be handed out on-site. 

34 

heat processing 3-2013


HärtereiKongress Wiesbaden, 

October 9th - 11th, 2013 

Visit us in Hall 9! 

AICHELIN Group: Booth 920 

NOXMAT: Booth 922 

Together one step ahead. 

www.aichelin.com 


35

PROGRAM 



Congress 2013 

Program 

Wednesday, 09 October 2013 

PRACTITIONERS’ SEMINAR (only in German language) 

9:00 - 10:30 h 

Grundlagen des Induktionshärtens – Möglichkeiten 

und Grenzen der Prozessregelung beim induktiven 

Wärmen 

Hansjürg Stiele 

10:30 - 10:45 h 

Coffee break 

10:45 - 12:15 h 

Energiemanagementsysteme in 

Wärmebehandlungsbetrieben – EnMS nach ISO 50001 

Energiekosteneinsparung und steuerliche 

Entlastungen 

Christoph Holzäpfel 

13:30 - 13:45 h 

Opening 

Michael Lohrmann 

STEEL QUALITY 

Chairmen: Michael Lohrmann, Berthold Scholtes 

13:45 - 14:20 h 

Survey lecture 

Increasing product demands – from the steel making 

point of view 

Christian Günther 

14:20 - 14:45 h 

Tayloring transformation kinetics for high robustness 

in mechanical properties of bainitic steels 

Frederic Marchal 

14:45 - 15:10 h 

Thermal shock behaviour of premium hot-working 

tool steels for high-pressure die casting 

Siegfried H. Wüst 

15:10 - 15:35 h 

Case hardening response and subsequent in-service 

properties of Ni-bearing and Ni-free carburizing steels 

Antoine LeBigot 

15:35 - 15:55 h 


DISTORTION 

Chairmen: Dieter Liedtke, Marco Jost 

or 

9:00 - 10:30 h 

Energiemanagementsysteme in Wärmebehandlungsbetrieben 

– EnMS nach ISO 50001 Energiekosteneinsparung 

und steuerliche Entlastungen 

Christoph Holzäpfel 

10:30 - 10:45 h 


10:45 - 12:15 h 

Grundlagen des Induktionshärtens – Möglichkeiten 

und Grenzen der Prozessregelung beim induktiven 

Wärmen 

Hansjürg Stiele 

15:55 - 16:20 h 

Residual stress and distortion development due to 

induction surface hardening – Identification of 

mechanisms by numerical modeling and experiments 

Maximilian Schwenk 

16:20 - 16:55 h 

Non-destructive residual stress analysis of steel shafts 

after different process steps from wire drawing 

to induction hardening 

Juan Dong 

16:55 - 17:20 h 

Simulation of tempering of a thick-walled 

X40CrVMo5-1 workpiece 

Atilim Eser 

36 


PROGRAM 

17:20 - 17:45 h 

Comparative study of oil- and watermiscible 

polymeric based quenchants regarding the distortion 

behaviour of thin-rolled bearing rings 

Timo Wolfrath 

18:00 h 

General meeting of AWT 

Thursday, 10 October 2013 

FORGING 

Chairmen: Jörg Kleff, Olaf Irretier 

9:00 - 9:25 h 

EcoForge: Energy efficient forging process chain for 

HDB (high-strength, ductile bainitic) steel parts 

Martin Fischer 

9:25 - 9:50 h 

Impact of cold forging and heat treatment on size and 

shape changes 

Dawid Nadolski 

FURNACE TECHNOLOGY AND TREATMENT MEDIA 

Chairmen: Franz Hoffmann, Klaus Löser 

13:20 - 13:55 h 


Overview and developments of industrial furnace 

technology for heat treatment of metals 

Olaf Irretier 

13:55 - 14:20 h 

Hot zone and cooling-gas stream design of onechamber-vacuum 

furnaces directed to application 

Björn Zieger 

14:20 - 14:45 h 

Plasma nitriding extended – Improvement of wear 

and corrosion resistance of nitrided and post-oxidized 

steels by additional low friction DLC coating 

Thomas Mueller 

14:45 - 15:10 h 

The ideal quenching medium? – Characterisation of 

new liquids for heat treatment of metallic components 

Martin Beck 

15:10 - 15:30 h 



9:50 - 10:15 h 


SAFETY ENGINEERING 

Chairmen: Jörg Kleff, Olaf Irretier 

10:15 - 10:50 h 


Safety engineering of heat treatment plants 

Frank Treptow 

10:50 - 11:00 h 

Bestowal of Paul Riebensahm Award 2012 to 

Katharina Steineder 


11:00 - 12:00 

Plenary lecture 

Living prototypes: Innovations from nature 

Antonia B. Kesel 

12:00 - 13:20 

Lunch hour 

PROCESS MONITORING AND PRODUCT QUALITY 

Chairmen: Hans-Werner Zoch, Olaf Keßler 

15:30 - 16:05 h 


Process monitoring and control in the course of time 

Karl-Michael Winter 

16:05 - 16:30 h 

Instrumented indentation test at 20MnCr5 for the 

estimation of the case hardening depth and the 

mechanical properties of the surface layer 

Andree Irretier 

16:30 - 16:55 h 

Quality control of cutlery based on short time 

corrosion testing 

Paul Rosemann 

16:55 - 17:20 h 

Accurate non-contact temperature measurements 

during surface heat-treatment processes 

Marko Seifert 


37

PROGRAM 


17:20 - 17:45 h 

QASS crack detection – now during hardening 

Ulrich Seuthe 

18:00 h 

Reception – Bestowal of the Karl Wilhelm Burgdorf 

Award 

Friday, 12 October 2013 

THERMOCHEMICAL TREATMENTS 

Chairmen: Michael Jung, Peter Krug 

9:00 - 9:25 h 

Nitrided forging dies 

Stefanie Hoja 

9:25 - 9:50 h 

Nitriding and nitrocarburizing of high-strength 

bainitic long products 

Mirkka Lembke 

9:50 - 10:15 h 

Investigations on the endurance limit of carbonitrided 

specimens 

Christoph Stöberl 

MICROSTRUCTURE AND PROPERTIES 

Chairmen: Michael Jung, Peter Krug 

10:15 - 10:40 h 

Investigation of the influence of nanocrystalline 

surface layers on the cyclic fatigue behaviour of 

machined AISI 4140 

Alexander Erz 

11:05 - 11:25 h 


MICROSTRUCTURE AND PROPERTIES 

Chairmen: Winfried Gräfen, Hansjürg Stiele 

11:25 - 11:50 h 

A new combined surface treatment technology for 

highly-loaded cast iron alloys safety engineering of 


Anja Buchwalder 

11:50 - 12:15 h 

Characterization of resistance spot welded 

aluminium-steel joints 

Mario Säglitz 

12:15 - 12:40 h 

Spray deposition for gradient forming in tool steels 

for micro cold forming 

Alwin Schulz 

12:40 - 13:05 h 

Adjustment of high retained austenite contents to use 

the TRIP effect in aluminium alloyed throughhardening 

bearing steels 

Holger Surm 

13:05 h 

Rendition of Paul Riebensahm laureate 2013 

Peter Krug 

13:10 h 

Closing words 


10:40 - 11:05 h 

In situ investigations of the martensitic 

transformation with synchrotron radiation – 

application at 20MnCr5 steel 

Jérémy Epp 

13:20 h 

End of the event 

Visit us at the HK 2013 

Vulkan-Verlag 

Hall 9 / Booth 905 

09 - 11 October 2013 

Rhein-Main-Hallen, Wiesbaden 

Germany 

38 


PRODUCT PREVIEW 

Visit us at the 

Heat Treatment Congress 

October 09-11 in Wiesbaden 

Hall 9, Booth 914 


Energy Consultant! 

Heat treatment is energy hungry. Because we know this, we 

have been facing this challenge for years, providing innovative 

and increasingly efficient heat-treatment solutions. Nonetheless, 

we are offering a broad spectrum of new improvements 

in equipment, processes, and control systems to save energy. 

For your business - and for advanced efficiency. 

Please visit: www.ipsen.de 


39



The UBQ family – A modular approach to production 

global rise in component production has increased 

A demand for heat treatment systems capable of meeting 

production needs today, yet scalable for future production. 

AFC-Holcroft offers many 

thermal processing solutions, 

and highlights one of the 

most flexible heat treating 

furnace designs available 

– the UBQ (Universal Batch 

Quench) system. The UBQ is 

capable of running a variety 

of metallurgical processes, 

and can be delivered as a 

single unit or as a complete, 

fully automated 

cell integrated with companion 

equipment such 

as tempering furnaces, 

pre-heat furnaces, spraydunk 

washers, forced air 

cool stations and more, all 

tailored to your specific needs. With 

its modular design, additional cells can be added for maximum 

productivity with consistent, repeatable metallurgical 

results. Another modular, flexible product featured is AFC- 

Holcroft’s EZ-Series endothermic gas generator, offering a 

unique, maintenance- and operator-friendly design. A 5:1 

turn down ratio provides substantial savings in operating 

costs vs. nitrogen methanol; often with return on investment 

less than one year. Units can be provided individually, 

or up to three units grouped into an array; each unit having 

standalone plug-and-play type control. 

When consistent high volume production is needed, 

AFC-Holcroft spotlights the classic pusher-style furnace for 

continuous throughput under protective gas atmosphere. 

The pusher-style furnace design allows the furnace chambers 

to be combined into one, or separated into multiple 

chambers for independent control over temperature and 

atmosphere. Many of the largest production sites worldwide 

rely exclusively on AFC-Holcroft pusher furnaces for 

maximum control and economy. With offices on three 

continents and partners worldwide, AFC-Holcroft stands 

ready to help meeting specific heat treatment needs, today 

and in the future. 

AFC-Holcroft 

www.afc-holcroft.com 


High-powered control system for smaller heat 

treatment installations 

With the newly 

developed controller 

DE-VX 4600 the 

equipment even of 

small heat treatment 

installations is no longer 

a question of the 

price. Thus, such installations 

can be integrated 

with all functions 

in the process supervisory 

system prosys/2. 

The compact control systems have been equipped with 

the latest network-compatible hardware technology; they 

have an integrated PLC and a great number of regulation 

algorithms and special functions. The demig philosophy 

of the compatibility of all demig controller families DE-VR 

4008 and DE-VX 4100 has been maintained. That means 

that all projects can be realized with the same configuration 

software and already existing projects are directly applicable 

after a modification of the digital and analog I/O assignment 

and slightly changes of the process views. Due to the uniform 

operating function, a further training is not necessary. 

Despite its compact structure, the controller DE-VX 4600 

is equipped with sufficient analog (I 8/O 4) and digital inputs 

and outputs (64 or 128) and can be used in a wide field of 

applications in the process engineering. High-performance 

Intel Atom processors (Multi-Threading able) are able to 

regulate even fast processes and complex calculations. 

The combination with the integrated PLC allows the 

application in all cases where sophisticated and complex 

problems of control and automation call for a solution, e.g. 

in the heat treatment of metals, glass and ceramics and in 

the chemical and foodstuff industries. 

demig GmbH 

www.demig.de 


40 



Hardening center for crankshafts 

Efficient 4-cylinder engines form the basis for the passenger 

car drive concepts of the future. This calls 

for innovative approaches to the hardening process 

which can be ideally implemented with the BAZ KW600 

hardening center. The hardening center is a new addition 

to the existing product range and was developed specially 

for 4-cylinder crankshafts. It is designed on the principle of 

machining centers and is suitable for crankshafts of up to 

600 mm in length. Emphasis was also placed on good energy 

efficiency, a high throughput, low operating costs and ease 

of operation. The pin bearings are hardened in module 1 and 

the main bearings in module 2 of the two-module system. An 

optional extension can also be integrated for the hardening 

of flanges, journals and gear wheels. The full encapsulation 

of the working areas permits complete extraction of quenching 

fumes. Efficient drive systems and assemblies as well 

as optimized inductors guarantee low energy consumption, 

good process reliability and maximum availability. Minimum 

space requirement, full accessibility on one level and a standard 

height of only 2.3 m 

are all revolutionary features 

of this type of hardening 

machine. Preceding and 

subsequent processes can 

easily be integrated. Connection 

to portal systems 

can be performed in the 

same way as for existing 

technologies for machining 

centers. All these innovative 

aspects of the BAZ KW600 

have aroused lively interest 

worldwide. 

Alfing Kessler GmbH 

www.alfing.de 


Gas Tight Roller Hearth Furnace Systems 

Hot-form hardening, 

annealing, hardening, 

sintering and brazing 

Heat treatment equipment 

using protective and reactive 

gases 

schwartz GmbH 

Edisonstr. 5 

52152 Simmerath 

Germany 

Internet: www.schwartz-wba.com 


Visit us at 

HK 2013: 

Hall 1, Stand 116a 

schwartz Heat Treatment 

Systems Asia (Kunshan) Co. Ltd. 

278 JuJin Road 

Zhangpu Town Kunshan City 

Jiangsu Province 

215321, P.R. China 

schwartz, Inc. 

2015 J. Route 34 

Oswego IL 60543 

USA 

41



Modular furnaces for different applications 

ICBP® FLEX is a modular furnace that was achieved with a 

very high focus on clients’ needs and offers the production 

capacity of a continuous furnace with more flexibility and 

all advantage of LPC technology. 

This furnace is ECM Technologies most diffused device 

around the world: it is offering a wide range of capacity 

(from 1 to 10 heating/carburizing chambers) according to 

the production needs. 

ICBP® JUMBO is the second main product presented 

by ECM. The new concept of modular furnace with independent 

cells is dedicated for very large production 

volume (from 4 to 12 heating/carburizing chambers or 

even more) and for specific applications requiring separate 

cells (according to aeronautical norms: fully compatible 

for AMS 2750 E). 

Both of these equipment offer easy extension possibility 

with additional quench and heating cells. They also 

integrate ECM latest progresses in power management, 

electrical and gas consumption, and reduction of maintenance 

time. 

ECM Technologies 

www.ecm-furnaces.com 


Furnace technology for a number of 

different requirements 

Elino Industrie-Ofenbau GmbH has been developing, 

designing, and manufacturing continuous plants for 

more than 50 years: roller conveyor and paternoster furnaces 

as well as chain conveyor furnaces, to name but 

a few. To this day, more than 100 plants for basic or very 

special requirements in the field of aluminium processes, 

and 4,000 plants in other fields of application have been 

delivered world-wide. 

Cast components, e.g. cylinder heads, engine bases, 

structural components as well as axle suspensions, are also 

heat treated as it is done with cold-formed aluminium sections 

and machined components. A very accurate temperature 

control during artificial aging and solution annealing 

is absolutely vital. Quenching processes after solution annealing 

are implemented using water, polymer or air depending 

on the customers’ requirements. Elino has longterm 

experience and can offer various very new designs 

for the processes under ambient air atmosphere and for 

special gas-tight designs with process gases, e.g. argon or 

nitrogen. The continuous furnaces made by Elino are fully 

technically developed, are sound and allow very long lifetimes. 

We have always been focussing our activities on the 

optimization of energy consumption. Depending on the 

process conditions, heat treatments of up to 1,000 °C can 

be carried out. Product specific internal fittings in the process 

chamber give ample scope for new products. Thermal 

exhaust air and exhaust gas purification are also included 

in our scope of performances. Turn-key plants including 

the belonging handling systems are Elino’s speciality. On 

the basis of the process parameters determined in the pilot 

plant in Elino’s technical centre, we cannot only scale 

up the system for industrial plants but also perform tests 

for new products. 

In 2010, the Elino Industrie-Ofenbau GmbH became 

a partner of the PLC Holding. Together with its subsidiaries 

Wistra, Elmetherm and Wisconsin Oven, Elino is now 

able to offer a wider product range delivered by a group 

of highly-specialized enterprises with a world-wide service 

and international production facilities. 

Elino Industrie-Ofenbau GmbH 

www.elino.de 


42 



CFC-Hybrid-System optimizes thermal treatment 

While at thermal treatments previously steel and cast 

grids and racks were used, today charging systems 

made from carbon fibre composites are the number one 

choice. The high load capacity combined with tensile and 

flectional resistance are the decisive arguments for the use 

of carbon materials which come into their own in automated 

processes. The low density and the light weight of C/C 

makes handling much easier and also ensures an excellent 

energy balance compared to steel or cast frames. 

As a perfect solution for working temperatures of more 

than 2,000°F offers GTD Graphit Technologie GmbH a hybrid 

grid, that employs a combination of CFC and ceramic 

parts. This patent-registered system brings the specific performance 

of the materials in line and considers the different 

thermal expansion coefficient’s of the treated materials. The 

ceramic parts of the hybrid grid are bound in a dove tail. This 

enables the system to be installed on walls without loosing 

the ceramic elements when they are transported or flipped. 

This also means that a hybrid grid can be used to load working 

parts with different contact points due to their shape like 

turbine blades. Further advantages of the hybrid grids are no 

contact reactions or distortion, light weight, excellent energy 

balance for low costs and long service. 

GTD Graphit Technologie GmbH 

www.gtd-graphit.de 

Hall 1 / Booth 108A 

AFC-Holcroft: 

Strength and Innovation since 1916. 

Powerful Solutions for the Future. 

As a privately owned company with thousands of installations worldwide, 

AFC-Holcroft is a worldwide leader in the heat treat equipment industry. 

One of the most diverse product lines in the heat treat equipment 

industry: Pusher Furnaces, Continuous Belt Furnaces, 

Rotary Hearth Furnaces, Universal Batch Quench (UBQ) 

Furnaces and Endothermic Generators. 

Robust construction and long service life, 

designed for ease of maintenance. 

Various global facilities in North America, Europe 

and Asia for fastest local delivery, service and support. 

HK 2013 Wiesbaden 

October 9–11, 2013 

UBQ: Universal Batch Quench Furnace. 

Ultimate in flexibility and versatility. 

Modularly constructed universal batch system 

with state-of-the-art technology. 

Delivers consistently high quality with predicable 

and repeatable results. 

Hall 1, Stand 129 

Get in touch with us today to learn more about how 

we can improve your production processes and 

how we can give you the edge over the competition. 

For further information please visit 

www.afc-holcroft.com 

AFC-Holcroft USA · Wixom, Michigan AFC-Holcroft Europe · Boncourt, Switzerland AFC-Holcroft Asia · Shanghai, China 


Phone: +1-248-624-8191 Phone: +41 32 475 56 16 Phone: +86-21-58999100 

43



New low NO x solution 

new development from Elster Kromschröder will 

A produce a drastic reduction in thermal NOx formation 

in ON/OFF-controlled high-speed burners. The 

patented Low-NOx solution menox® consists of the new 

burner type BIC...M, which can function in two operating 

modes using special control equipment: in traditional 

flame mode at low furnace temperatures and in menox® 

low NO x mode with flameless combustion at higher furnace 

temperatures. With the help of menox®, NO x values 

can be reduced to below 150 mg/m³ (reference value of 

5 % O 2 ) even at a furnace temperature of 1,200 °C and 

hot air at 450°C – and all this, without 

expensive additional piping. 

This makes the 

method ideal 

for heat treatment 

processes, 

with the 

high output 

pulse frequency and a rotary impulse 

system ensuring temperature uniformity 

which is of great advantage. 

In order to heat up the furnace, the burner operates in traditional 

flame mode. The ignitable gas/air mixture is ignited 

using an electrical ignition spark and combusts inside and outside 

of the ceramic burner tube. An ionization electrode monitors 

the presence of the flame in compliance with EN 746-2. 

When the combustion chamber temperature rises 

above 850°C, the system is switched to menox® low NO x 

mode by a safety temperature monitor (STM) and a specially 

modified burner control unit BCU 465..menox. At 

this point, the burner is initially switched off and then restarted 

in the new operating mode. In menox® mode, the 

gas valve and air control valve are opened without triggering 

the electrical ignition spark. Gas and air are supplied 

through the same connections as in flame mode. 

However, the mixture is not ignited in the ceramic burner 

tube but instead the chemical combustion reaction occurs 

in the furnace. In menox® mode, the oxidation reactions 

take place without a visible flame. Compared to 

traditional flame mode, the reaction zone is considerably 

larger and the reaction density considerably lower. This 

prevents the peak temperatures responsible for high NO x 

values, thus drastically reducing NO x emissions. 

Although two operating modes are possible depending 

on the combustion chamber temperatures, there is 

only one connection for combustion gas and one for 

combustion air. As a result of the fact that the design 

is identical to the BIC burner, the identical dimensions 

of the burner housing for the BIC…M mean that it can 

also be used for retrofitting existing installations which 

currently feature conventional BIC burners. The burner 

BIC…M is available in various lengths which allows adaptation 

to various furnace wall thicknesses. 

Elster GmbH 

www.kromschroeder.com 

Foyer OG / Booth 06 

Annealing and hardening furnaces 

Industrieofen- & Härtereizubehör GmbH, Unna (IHU) 

is engaged in the design, manufacture and selling of 

annealing and hardening furnaces, as well accessories and 

spare parts for all usual industrial furnaces. IHU also conduct 

maintenance work for and can fall back to decades 

of experiences in the building of industrial furnaces with 

all necessary equipments. IHU is particularly specialized in 

the manufacture of tubes made of sheets in more than 80 

different qualities. 

Industrieofen- und Härtereizubehör GmbH Unna 

www.ihu.de 


44 


Handbook of 

Aluminium recycling 

Mechanical Preparation | Metallurgical Processing | Heat 

treatment 

the Handbook has proven to be helpful to plant designers and operators 

for engineering and production of aluminium recycling plants. the 

book deals with aluminium as material and its recovery from bauxite, 

the various process steps and procedures, melting and casting plants, 

metal treatment facilities, provisions and equipment for environmental 

control and workforce safety, cold and hot recycling of aluminium including 

scrap preparation and remelting, operation and plant management. 

Due to more and more stringent regulations for environmental control 

and fuel efficiency as well as quality requirements sections about salt 

slag recycling, oxy-fuel heating and heat treatment processes are now incorporated 

in the new edition. the reader is thus provided with a detailed 

overview of the technology of aluminium recycling. 

editor: C. Schmitz 

2 nd edition 2013, approx. 500 pages, hardcover 


Vulkan-Verlag GmbH, Huyssenallee 52-56, 45128 Essen 


knowledge for tHe 

future 

order now by fax: +49 201 / 82002-34 or send in a letter 

Deutscher Industrieverlag GmbH | Arnulfstr. 124 | 80636 München 

Yes, I place a firm order for the technical book. Please send 

— copies of Handbook of Aluminium Recycling 2nd edition 2013 

(ISBN: 978-3-8027-2970-6 ) at the price of € 130,- (plus postage and packing) 

Company/institution 

first name and surname of recipient 

Street/P.o. Box, No. 

Country, Postcode, town 

reply / Antwort 

Vulkan Verlag GmbH 

Versandbuchhandlung 

Postfach 10 39 62 

45039 Essen 

GERMANY 

Phone 

e-mail 

Line of business 

fax 

Please note: According to German law this request may be withdrawn within 14 days after order date in writing 

to Vulkan Verlag GmbH, Versandbuchhandlung, Postfach 10 39 62, 45039 essen, Germany. 

In order to accomplish your request and for communication purposes your personal data are being recorded and stored. 

It is approved 3-2013 that heat this data processing may also be used in commercial ways by mail, by phone, by fax, by email, none. 

this approval may be withdrawn at any time. 

✘ 

Date, signature 

PAHBAr2013 

45



Introduction of power controller 

Invensys Operations Management, a leading global 

provider of technology, software and consulting services 

to industrial and commercial operations, formally 

has introduced the Eurotherm EPack single phase 

power controller. This innovative, powerful and extremely 

compact instrument uses the latest technology to 

deliver effective process management and offer significant 

reductions in energy costs. Every part of the EPack 

controller has been designed to meet the fundamental 

customer requirements of maintaining yield and quality 

while working to reduce operational costs. 

The EPack power controller 

supports a wide 

range of firing modes 

and load types to ensure 

the accurate application 

of electrical energy. This 

increases the precision 

and repeatability of a 

process, bringing better 

quality results with decreased 

downtime and 

scrap. At the same time 

energy costs can be reduced by up to 20 %: Better management 

of power demand lowers peak current which 

can reduce the fixed part of an energy contract with up 

to 15 % savings on energy costs. The advanced firing 

modes further offer the potential to improve the power 

factor and reduce penalties imposed by energy suppliers 

– offering additional savings on energy costs of up 

to 5 %. 

The smart EPack power controller provides extensive 

processing information, including advanced measurement 

data and energy consumption along with full 

diagnostic and fault detection information on its color, 

front panel display and via integral Ethernet communications. 

This in-depth information offers the potential 

to reduce the time taken to detect faults and facilitates 

continuous process improvements from the advanced 

measurement information made available. 

Invensys Systems GmbH, Eurotherm 

www.eurotherm.de 


Exchange service for furnaces 

Unscheduled repairs result to annoying and expensive 

production interruptions in any production process. 

With the Kerfa® package "Always hot" craft sector and industry 

will be provided a comprehensive tool reducing 

these downtimes substantially. 

Regardless whether there is a need of a heating plug, 

an air heating cassette, a Kerfa® meander heating element, 

a Kerfa® heating coil, a complete vacuum formed Kerfa® 

SAVAC® heating system for electrical furnaces or a vacuum 

formed Kerfa® SAVAC® insulating system for gas-fired furnaces, 

the Kerfa® package "Always hot" is available in different 

varieties up to a possible consignment stock system. 

All products can be produced in different variants. 

Kerfa GmbH 

www.kerfa.com 


46 



New controller generation to control C-level and 

temperature 

Carbomat 300 is an universal program controller with 

the ability to control e.g. C-level and temperature 

in the furnace. Touch screen colour display, data logger 

with graphical display, various connection options and 

communication protocols are in use. Using Carbo 300 

in carbon applications, for example, the controller can 

be operated with various sensors, such as O 2 -probe, 

Lambda-probe, CO 2 /CO gas analysis unit. An additional 

control loop can be integrated to control the oil bath 

temperature. Carbomat 300 regards in the regulation 

of the process important parameters such as factor of 

alloy, soot limit etc. It contains a flushing function for 

the probe and monitors its quality. Thanks to its many 

control tracks this controller simply is able to control little 

Chamber furnace plant with charging unit 

The furnace plant serves for the controlled cooling 

down of ingots and the pre heating of blocks, max. 

13,2 to plus intermediate layers. The furnace plant consists 

out of a chamber furnace with hydraulically operated 

lifting door arranged at the longitudinal side of the furnace. 

c\aaa\anzeigen\vulkan\EW The heating of the furnace plant HP is 13.qxd done electrical 

using meander shaped heating elements installed in the 

furnace back wall and in the furnace door. 

The plant allows operation up to max. 900°C using 

free programmable temperature curves. The cooling 

function of the furnace plant is done through twelve 

Mikrowellenerwärmung 

pieces cooling nozzles, the control ranges from maximum 

to off. The cooling nozzles and electrical heating 

is divided into three control zones. For the necessary 

convection during the heating operation six pieces hot 

gas circulation fans are used. Hence the highest possible 

temperature uniformity in the furnace and hence also at 

the load can be achieved. 

Elektrowärme; Heat processing 2013 

furnaces without PLC-control or is master of a PLC. The 

unit is able to communicate with automation equipment 

using communication protocols as in MODBUS RTU, TCP, 

Ethernet and PROFIBUS. 

Carbomat 300 offers a feature “Foil test” to correct the 

C-level generated by the Carbomat 300 by using reference 

values obtained from the special carburized foil to the actual 

reference value. An integrated data logger allows recording 

of the measurements. The data can be visualised 

and analysed by the dedicated PC-software. 

Mesa Electronic GmbH 

www.mesa-international.de 

Foyer 1 st Floor / Booth 01 

Industrieöfen Präzisionsfeinguss Induktionserwärmung 

Elektrowärme 2 /13 

The loading and 

unloading of the furnace 

plant with the 

ingots and/or blocks 

is executed using the 

in 182 front xof 31the 1/8furnace 

4c 

plant installed charging 

unit. The charging 

unit consists of charging 

machine with an insertion manipulator, pusher units 

for the ingot positioning, roller conveyor complete with 

roller conveyor control and safety technique and conveyor 

frame with adaptor. 

IOB Industrie-Ofen-Bau GmbH 

www.iob.de 


ITPS 

Düsseldorf 

9.-10.7.2013 • B-02 

www.linn.de 


Industrial furnaces Microwave heating Precision fine casting Induction heating 

Productronica 

München 

12.-15.11.2013 • B2 / 479 

www.linn.de 

Heat processing 3 /13 


Industrieöfen Schutzgasöfen Präzisionsfeinguss Induktionserwärmung 

47



Partner in hot-forming of 

automotive body parts 

Heat treatment lines made by Schwartz GmbH can be 

found in manufacturing plants worldwide, wherever 

automotive body parts are heat-treated to boost their 

strength. The company’s furnace equipment is noted for its 

unsurpassed cost-efficiency, high availability and exceptional 

process reliability. 

Fast-paced growth in demands, e.g., regarding surface 

finish, varying hardness levels across the part, tailored 

blanks, and component lightweighting is addressed via an 

ongoing refinement of furnace systems. Diverse furnace 

designs are adopted, depending on requirements and 

local circumstances, and coordinated in detail with the 

prospective user. In these furnaces, the parts can be heattreated 

in a normal or controlled atmosphere or in dried air. 

Automation systems of proven safety and dependability 

ensure minimum cycle times and high availability levels. In 

addition, Schwartz GmbH’s product range comprises hardening 

lines for steel forgings as well as solution annealing 

lines with water quench for aluminium castings and forgings, 

profiles, tubes and bars intended for use in aerospace 

and automotive applications. 

Modern processing 

technology 

The systems of Mioba are manufactured to the highest 

degree of quality in capable an efficient production 

facilities in accordance with DIN EN 9001 standards. Forging 

furnaces with integrated residual heat exploitation. 

Heating with waste gas (coke + natural + converter gas) 

by using flexible and state of the art burner technology. 

Economies of more than 30 % of the required energy possible. 

By using the converter gas no disposal of the waste gas 

is required (by burning off). The use and the combustion of 

the converter gas does not lead to polluting by- products. 

Forging furnace S500 to 32 m long, 6 m wide, 5 m high. 

Together with the customer, a flexible team of experienced 

engineers develops and constructs furnace systems according 

to the customer´s specific requirements. 

Schwartz GmbH 

www.schwartz-wba.de 

Hall 1 / Booth 116a 

MIOBA GmbH & Co. KG 

www.mioba.com 


48 



Roller hearth furnaces for quality controlled hardening 

of bulk material 

Bulk material is typically hardened in mesh belt furnaces. 

A principal problem of this type of furnaces is the fact 

that even though all heat treatment parameters are carefully 

controlled and documented it can be happen that soft 

parts or mixing of parts can occur. Due to these problems 

the utilization of belt furnaces for parts of high quality 

requirements or safety relevance is more than critical. 

A proven alternative are roller hearth furnaces where 

the parts run through the furnace in small, light baskets 

which guarantees a hundred per cent distinguished and 

traceable charge control. 

The new developed modular SRS-Roller hearth Furnace 

System is characterized by cost reduced, compact and extensively 

pre-assembled design which allows short installation 

and start up times. A special highlight is the design of the 

lowering mechanism which achieves extreme fast crossing of 

the parts into the quench bath. The quench module is available 

for quenching into oil or salt. The washing, rinsing and 

drying modules are also modular designed and will be customer 

tailored combined. The material handling can be fully 

ore semi-automated. Additionally to the high level of quality 

assurance the systems has some more advantages: Considerably 

reduced consumption of heating energy and protective 

gas as well as high flexibility in changing the product. 

SRS Industrieofenbau GmbH 

www.srs-industrieofenbau.de 

Foyer 1 st Floor / Booth 21 

Improved assessment of nitriding processes 

by layer module 

The software module to calculate the nitriding hardness 

depth and the compound layer was developed 

by Stange Elektronik in cooperation with Spies & Partner 

as well as the Institute for Materials Engineering at the TU 

Bergakademie Freiberg in Germany. It is a novel method 

for calculating the expected compound layer thickness 

CLT, nitriding hardness depth NHD and case hardness 

RH in dependence of treatment temperature, processing 

time and nitriding potential Kn for different nitriding 

processes. The calculation is based on numerous test 

results with different furnaces and different batches in 

order to determine the growth of the compound layer. 

These test results are stored in the integrated steel data 

base with more than 30 of the most used steel grades. 

The database is permanently updated and expanded. 

The calculation algorithm is now significantly accelerated 

caused by the new practical calculation basis in contrast 

to previous calculation programs. This enables the 

immediate and automatic recalculation of each change 

in value and the display of the results without delay. The 

major advantage for the user is to evaluate the effects 

immediately and thereby get a feeling for the nitriding 

process when changing parameters. As a specialist in 

control engineering Stange Elektronik offers a valuable 

tool as a further development of the nitriding potential 

module and the nitriding case depth calculation in order 

to achieve reproducible nitriding results. 

Stange Elektronik GmbH 

www.stange-elektronik.com 




49



Nitriding, nitrocarburising and mechanical finishing 

The Hauck Group consistently adjusts services to meet 

global challenges and thus are leaders in heat treatment 

and surface coating technology for high-value 

components and toolings. Hauck is a leading supplier 

to the core industries: automotive, mechanical, electrical 

and medical engineering. Hauck’s setup is prepared to 

offer almost any industrial applied heat treatment procedure, 

both thermal and thermo-chemical – across the 

different group locations. The technical consultants are 

available whenever seeking for advice regarding new product 

developments or solutions to complex projects and 

supporting from the design phase right through to the 

production phase of the project. 

This year, we particularly like to highlight our PE-CVD process 

where DLC (diamond-like carbon coating) layers can be 

applied (V-Proteq®). This particular coating process will be offered 

either solo or in combination with the standard heat 

treatment procedures. Beyond this background we have 

enlarged the already existing hard coating department according 

to the state of the technology as well as the recently 

launched process with the registered trademark MeNit®. This 

newly developed process is a combination of nitriding/nitrocarburising 

and mechanical finishing. 

Härterei Hauck GmbH 

www.haerterei-hauck.de 


New temperature controller for fast processes 

Measuring and controlling temperature is one of the 

most important tasks in the process and automation 

technology. An accurate temperature controlled 

measurement can greatly improve quality, reduce waste 

and increase product yield. Sensortherm has expanded 

its product range to include the Regulus Controllers, RD 

and RF versions. These temperature controllers were 

specifically designed for the most stringent inductive 

and conductive heating application requirements. With 

an extremely fast sampling time of 100 μs and extensive 

control and monitoring capabilities, the RD 

and RF controllers are the perfect solution for 

the most demanding process control applications 

found in the industry. 

In combination with Sensortherm’s high 

speed pyrometers, measuring and controlling 

high speed processes is made easy. 

Other benefits include the use of a bumpless 

control feature that merges a thermocouple 

and pyrometer input to combine 

a wide temperature measurement range 

control scheme, also, the user-friendly integrated 

Auto-Tune feature that simplifies 

user operation by quickly finding the necessary 

control parameters. 

For system integration and communication with 

a PLC, six digital inputs, seven digital outputs, a 0-10 V 

control output, a serial interface and a Profinet module is 

provided. Included in the scope of delivery is the extensive 

Regulus II Win software that enables easy adjustment 

of all parameters. 

Sensortherm GmbH 

www.sensortherm.de 

Foyer 2 nd Floor / Booth 09 

50 



REPORTS 

Assessment and optimisation 

of energy efficiency in heat 

treatment plants 

by Jürgen Krail, Klaus Buchner, Herwig Altena 

The last years are marked by heavily fluctuating energy costs and uncertainty in energy supply. Prognoses exhibit a 

dramatic gap between supply and demand on fossil energy carrier in the years to come. Energy efficiency is the key to 

supply the future worldwide energy demand. In Austria and Germany process heat represents a considerable portion 

of total energy consumption. Targeted primary measurements and a consequent utilisation of waste heat in plants may 

lead to a significant improvement of plant efficiency and in consequence to a reduction of the CO 2 -emissions. By way 

of example of a gas-fired pusher-type furnace for carburising internal and external efficiency increasing measurements 

are demonstrated and its influence on the overall process is assessed. 

In the last years political and economic crises caused 

a heavy fluctuation in energy costs and uncertainty in 

energy supply. Prognoses concerning the worldwide 

supply of fossil energy carrier exhibit that the Global Oil 

Peak has already been reached. 

The prognosis of the oil production shows a significant 

reduction of quantity in the years to come, although the 

demand is still increasing (Fig. 1). Similar tendencies can 

be observed at other non-renewable energy carriers. The 

unbalance between supply and demand logically results 

in a rise in price of energy carrier and a shift to other fossil 

or renewable energy sources. From an energy-political 

sight exerted energy markets are the consequence, which 

influences the economic as well as the social surroundings. 

Increasing energy efficiency is the first step to counteract 

that development which results in a reduction of 

primary energy consumption. Sustainable house holding 

in the sectors energy supply and domestic heating has 

become a central topic. Regarding the sectors industry 

and transport, sustainability has also become a focus of 

interest in the past years, even though its achievement in 

these sectors is much more difficult. 

ENERGY-ECONOMIC RANGING OF 

INDUSTRIAL FURNACES 

The sector industrial furnaces assume with 14.3 %, 

based on the Austrian total energy balance of the year 

2011, the third rank, after the sectors traffic and buildings 

(room heating, air condition and hot water). The 

annual energy consumption in the said sector amounts 

to 155.5 PJ (in the year 2011); it was increased by 23.7 % 

between 1995 und 2011. Considering the electric energy 

consumption the portion of industrial furnaces comes 

to 50.2 PJ (23.1 %) in the year 2011; thereupon industrial 

furnaces is placed on the second rank behind stationary 

engines. The increasing rate from the base year 1995 

amounts to 43.0 %. Energy supply is predominately 

carried out with oil (39.1 %), followed by electric energy 

(19.4 %), renewable energy (14.5 %) and district heat 

(6.5 %) [2]. 

In Germany the sector other process heat, with 

1,979 PJ or 22.6 % of the total end energy consumption of 

the year 2011, holds up the third rank behind the sectors 

mechanical energy (3,327 PJ; 38.1 %) and domestic heating 

(2,256 PJ; 25.8 %); the increasing rate from 2008 to 2011 

amounts to 5.5 % [3]. 

These figures evidently show that in both countries 

the two sectors – although not directly comparable 

due to the different boundaries – take up a substantial 

portion of the total end energy consumption. 

With respect to the temperature level of the industrial 

process heat demand more than 50 % is consumed 

above 800 °C. Fig. 2 shows a detailed analysis considering 

different sectors and temperature levels. 


51

REPORTS 


Fig. 1: Overview and prognoses of the worldwide oil production [1] 

Fig. 2: Fuel utilisation for industrial process heat in different temperature levels and industrial sectors [4] 

Symbol 

dA t 

dQ a 

Σdm i (h i + e ai ) 

dU 

dE a 

Q˙ 

P 

Ḣ 

Name 

Technical work, achieved beyond the boundary of the system 

Heat, provided beyond the boundary 

Sum of enthalpy and external energy, transported by in- and outflowing mass streams 

Increase of the inner energy of the system 

Increase of the outer energy of the system 

Heat flow 

Power (mechanical) 

Enthalpy stream 



REPORTS 

ANALYSIS AND ASSESSMENT OF MASS- 

AND ENERGY-STREAMS IN INDUSTRIAL 

FURNACES 

Energy balance of thermal process plants 

In order to detect saving potentials a detailed mass- and 

energy-balance has to be set up. A base therefore represents 

the First Law of thermodynamic: 

dA t + dQ a + Σdm i (h i + e ai ) = dU + dE a (1) 

In case of a stationary flow process this generally valid 

formula can be developed to an integrated formula; in 

most cases a change in kinetic and potential energies can 

be neglected. Hence it follows: 

Q˙ 12 + P 12 = (Ḣ 2 – Ḣ 1 ) (2) 

The energy streams required can be divided in useful 

energy (heat required for the heating of the incoming 

charge), heat losses (for instance surface losses of the 

plant) and system inherent losses. System inherent losses 

are known for instance heat flows required to heat up 

streams and structures of the plant (for instance grates), 

which cannot be defined as useful for the unit operation 

itself, but necessary for the plant operation. 

Methodology to analyse 

mass- and energy-streams 

Energy streams can be assessed either through a calculated 

balance (set up of an energy balance over a suitable system 

boundary) or by means of measuring; both variants have 

the disadvantage of certain uncertainty. 

This uncertainty concerns in case of a calculated balance 

for instance the surface heat loss (influence of heat 

bridges, fins, etc.) and the lack of exact knowledge of 

the thermodynamic operations within the furnace (heatup 

behaviour, transferred heat flow from burners and 

radiant tubes). 

In case of measuring an assessment of the complete 

energy streams is not suitable in large and complex 

plants because of the high expenditure of measuring 

devices. Furthermore the measure device itself contains 

some inaccuracies and non-stationary operating conditions 

are commonly even more difficult to evaluate. 

Choice of the system boundaries 

The whole process is suitably divided in subsystems with 

own boundaries. One has to distinct between spatial or 

temporal system boundaries. Boundaries can be defined 

for the whole plant as well as for components (burners, 

recuperates, regenerators). 

Defining the efficiency in thermal 

processing plants 

Generally valid efficiency can be defined as: 

η = 

usefulness 

expenditure 

In case of industrial furnaces a more focused consideration 

is necessary. Usually, the usefulness is the heat to warm up 

the charge targeted temperature. 

Due to process requirements it may occur that the 

charge temporarily should be heated to targeted temperature 

and be cooled afterwards. This may be the case 

in carburising furnaces in the carburising zone (higher 

temperature level) and the following diffusion zone (lower 

temperature level). The increased temperature in the carburising 

zone yields in increased heat losses on the outer 

furnace walls as well as in increased heat losses of the 

burner; this increases the expenditure without increasing 

the usefulness. In order to come to comparability an exact 

definition of the targeted temperature has to be made. 

Also the definition of the charge needs a more adequate 

consideration. In batch-operated furnaces the tray is also 

exposed to the temperature excursion of the whole thermal 

process without claiming usefulness. Therefore, the 

mass-ratio of the charge over the grate has an essential 

influence on the efficiency of the heat treatment process. 

The expenditure is given by the amount of consumed 

fuel gas and electric energy. In thermo-chemical processes 

however flammable gases are used. Hence the chemical 

as well as the caloric enthalpy of the process gases have 

to be considered as an additional expenditure. Furthermore 

the electric power consumption of electric driven 

components (for instance circulators) has to be included 

in a total expenditure. 

Regarding the definition of the efficiency the following 

questions are [5]: 

■■ 

■■ 

■■ 

To which extend is the heating energy consumed? 

Which portion of that energy is used for the useful 

increase of enthalpy within the charge? 

How high is the required expenditure to cover the 

increase of enthalpy within the charge? 

These conventional definitions of the efficiency may be 

extended by accounting the auxiliary energy: 

■■ 

How high is the expenditure of the total energy (energy 

of the heating agent, energy consumption of components, 

energy contents of consumables for the thermo-chemical 

treatment) compared to the increase of 

enthalpy of the charge? 

Corresponding to the posed question different definitions of 

the plant efficiency are possible. Fig. 3 exhibits an overview 

of different efficiency definitions with the energy streams to 

be considered in case of a carburising furnace. 

The term total efficiency (of the furnace or the whole 

plant) is common if the expenditure is based on the energy 

content of the fuel as well as of the power. 

(3) 


53

REPORTS 


Emissions and primary energy consumption to 

provide energy carrier 

The provision of energy carrier, necessary for the operation 

of thermal process plant, is accompanied with the emission 

of CO 2 . These emissions start with the production, 

provision, processing, transport and storage. This chain of 

procedures, ending at the location of the end-user and the 

time point of delivery is known as up-streams. The conversion 

of the primary energy to the desired end-energy (for 

instance mechanic or thermal energy) is carried out at the 

end user. Fig. 4 represents the simplified process chain of 

providing fossil energy and electric energy, generated from 

fossil or from wind energy. 

The greenhouse gas relevant emissions are – depending 

on the energy carrier, the expenditure for its exploitation, processing, 

transport and storage – different. Table 1 gives an 

exemplary overview of the greenhouse gas relevant emissions 

for different energy carriers (natural gas, electrical power from 

a mixed production and poorly from wind energy). 

In case of natural gas-fired plants emissions will be 

set free during combustion (“conversion”). In case of the 

direct use of electric power emissions arise due to the upstream 

processes, even in the case of wind energy sources, 

because the installation of wind energy plants requires 

energy carriers, which contain fractionally also fossil fuels. 

ANALYSIS AND ASSESSMENT OF MASS- 

AND ENERGY-STREAMS 

Considered Plant 

The analysis is focused on a gas-fired pusher-type furnace 

(Fig. 5), which is used for gas carburising in the automotive 

industry. The plant operation can be considered as 

a quasi-stationary flow process, because the batch-wise 

charging causes only negligible fluctuations of the process 

parameters. 

The pusher-type furnace plant contains the following plant 

units: 

■■ 

Preheating furnace (gas-fired), 

■■ 

Carburising furnace (gas-fired) with an oil bath for 

quenching, 

■■ 

Washing machine (electric and gas heated) and 

■■ 

Tempering furnace (electric heated) with a cooling 

tunnel. 

Fig. 3: Overview of energy flows and different definitions of efficiencies 

by way of example on a hardening furnace (carburising furnace) 

Process parameters 

Because of metallurgical requirements different process 

conditions in terms of atmosphere, temperature as well 

as retention time are needed. Fig. 6 shows a schematic 

diagram for a typical thermal treatment process. 

Energy consumption of the plant 

The energy consumption of the carburising furnace – 

which is the most important energy consumer – is treated 



REPORTS 

Fig. 4: Simplified 

process 

chain of 

the utilisation 

of different 

energy 

carrier 

in detail. The choice of the boundary has been carried out 

in that way, that the system boundaries coincide with the 

temperature control zone. Due to this methodology the 

consumption of the burners and the exhaust gas flow – 

ready for heat recovery – can be determined. The furnace 

has four zones with an operating temperature of 925 °C 

(preheating zone 1+2, carburising zone 1+2) and one zone 

with a temperature of 860 °C (diffusion zone); the charge 

itself has an inlet temperature of approx. 400 °C. 

The operation data are typical for a medium-sized plant 

with a moderate utilisation; an overview of the energy 

streams within the different zones is given in Fig. 7. Annual 

natural gas consumption for combustion atmospheric use 

(process gas) is 310,000 m³ (standard conditions), yielding 

to a CO 2 -emission of 748 t/yr. 

Measures to increase efficiency 

The analysis of the energy streams disclose saving potentials, 

which directly influence the energy consumption 

of the plant (process-internals potentials, for instance 

an improved heat insulation) and on the other hand 

potentials, which do not lead to a consumption reduction, 

but enable a recovery outside the process (for instance 

waste heat recovery). 

Measures to increase energy efficiency in carburising 

furnaces are improved heat insulation, the heat recovery 

from the exhaust gas of the burners as also the utilisation 

of the Endogas for the heating of plant components, which 

is at present dispatched via a flare. 

A process-external utilisation is the waste heat recovery, 

for instance for heating purposes (directly or via a heat 

transformer) or for cooling production (via an absorption 

cycle). These potentials are depending on a bundle of sitespecific 

conditions. An optimum integration of a process in 

an operational energy concept always requires an extensive 

consideration of the site conditions. 

Energy consumption of the plant utilising 

efficiency increasing measures 

Fig. 8 shows the energy streams of the optimised version, 

which takes into account the already mentioned efficiency 

increasing measures. 

Table 1: Greenhouse gas relevant emissions, expressed as CO 2 -equivalent, and cumulative energy expenditure to produce heat 

Greenhouse-gas relevant emissions, in CO 2 -equivalent [kg CO 2 /GJ] 

Up-stream Conversion Total 

Natural gas 10.5 1 55.4 2 65.9 1.14 1 

Electric power, mixed production 111 1 0 111 2.53 1 

Electric power, wind energy 6.58 1 0 6.58 1.05 1 

Literature: 1 [6] 2 [7] 

Cumulative primary 

energy expenditure 

[GJ/GJ] 


55

REPORTS 


measurements – can theoretically be increased by 19 %. 

Tables 2 and 3 give an overview of the saving potential. 

PRACTICAL EXAMPLES TO INCREASE 

EFFICIENCY 

In addition to the already mentioned possibilities further 

measurements – partly already applied – should be disclosed. 

Fig. 5: Pusher-type furnace plant for carburising 

Utilising all optimising potentials the natural gas consumption 

for heating and atmospheric treatment can be 

lowered to 303,000 m³/yr. The recovery of the waste heat 

potential enables an additional reduction of 105,000 m³ 

– expressed as natural gas equivalent – per year. Taking 

all the potentials into account a theoretical reduction of 

CO 2 -emissions up to 482 t/yr can be achieved. The processtechnical 

total efficiency – considering all the mentioned 

Process-internal measures 

Beside the already discussed aspect of the targeted utilisation 

of the process gas in lean-gas burner the gas consumption 

itself should be critically analysed. Especially for 

chamber-furnaces it is common practice to determine the 

amount of process gas for the worst case – large charge 

surface and low case hardening depth (CHD) – and keep 

that flow constant. By means of modern control systems 

it is however possible to adapt the flow according to the 

actual requirements. The rate of carburising decreases with 

increasing process time because the C-content of the surface 

tends to the C-potential of the atmosphere according 

to the √t-law. Investigations under common circumstances 

in hardening shops have shown that the process gas consumption 

can be reduced by 40 % without impairment 

of quality for a CHD of 0.7 mm (Fig. 9). In case of a CHD 

≥ 1.5 mm the gas flow can be reduced after three to four 

hours, which results in an additional saving potential. By 

Fig. 6: Temperature 

vs. Time- 

Diagram 

(set temperatures) 

of the heat 

treatment 

(without 

consideration 

of the 

manipulation 

time 

between the 

plant units 

and without 

time periods 

for charge 

cleaning) for 

a target CHD 

of 1.45 mm 



REPORTS 

Table 2: Efficiency of the plant components 

Total process technical efficiency [%] 

Before After Difference 

Preheating furnace 44.9 54.0 +9.1 

Carburising furnace 8.7 27.7 +19.0 

Tempering and relieving furnace 56.1 52.2 -3.9 1 

1 

Efficiency deterioration caused by the partial substitution of power trough natural gas, but decrease of CO 2 -emissions 

Table 3: Annual theoretic saving potential of natural gas equivalent, electric power and CO 2 -emissions for the pusher-type furnace plant 

Utilisation 

Saving potential 

Processs-internal/ 

external 

natural gas equivalent 

per year [St.m³] 

Electric power 

per year [TJ] 

CO 2 -emissions 

per year [t] 

Reduction CO 2 - 

emissions [%] 

Preheating furnace 

internal 

external 

Total 

1,420 

3,000 

4,420 

– 

– 

– 

3.3 

7.0 

10.3 

-10 % 

(Base 107 t) 

Carburising furnace 

internal 

external 

Total 

7,690 

146,000 

154,000 

– 

– 

– 

18.0 

344 

362 

-48 % 

(Base 748 t) 

Oil bath 

internal 

external 

Total 

– 

69,300 

69,300 

– 

– 

– 

– 

163 

163 

Tempering furnace 

internal 

external 

Total 

- 8,850 1 

0.293 

– 

– 

- 8,850 1 0.293 

11.8 

– 

11.8 

-29 % 

(Base 41.2 t) 

Gas-fired pusher-type 

furnace plant 

internal 

external 

Total 

262 

219,000 

219,000 

0.293 

– 

0.293 

33.1 

514 

547 

-61 % 

(Base 896 t) 

1 Increased natural gas consumption caused by the partial substitution of power trough natural gas for heating purpose 

this way the consumption of process gas can be reduced 

up to 70 %. 

An additional aspect, which is currently considered 

critically under the aspect of amortisation and the lifetime, 

is the use of carbon fibre reinforced (CFC) trays and 

charging racks, which are currently occasionally applied 

in vacuum plants. Because of the high strength of CFC at 

high temperatures a reduced wall thickness respectively 

weight compared to cast designs can be realised. For this 

reason charging loss can be reduced significantly (approx. 

50 %) [8]. For gas carburising heat treatment plants with 

oil quenching trays and charging racks with a ceramic 

coating can be applied. However a dense coating with 

sufficient alternating temperature strength, to withstand 

quenching in the oil bath without crack formation, is still 

under development and may be available in some years. 

Concerning the saving potential in drives the motor 

itself as well as its control is to be considered. Especially in 

the application of continuously operated drives (circulator 

respectively fan for combustion air as well as waste gas) 

high efficient electric motors (defined by the European 

Committee of Manufacturers of Electrical Machines and 

Power Electronics) offer a 2 to 6 % higher efficiency than 

conventional motors. 20 to 30 % higher investment costs 

lead to an amortisation period of approx. two to three 

years. Usually the rated motor poser is higher than the 

required mechanical power. Besides that, some operating 

conditions require a lower load in terms of power 

and speed. In order to enable an optimum operation 

concerning the actual efficiency and the reactive power, 

frequency converters can provide electric power with a 

controlled frequency, voltage and phase shift. Beside the 

additional investment cost of the frequency converter 

modifications of the electric and the control system have 

to be taken into account. 

Process-external measures 

Although process-internal improvement of energy efficiency 

is the first choice additional heat recovery may be 

increasingly economic because of rising energy costs. 


57

REPORTS 


Fig. 7: Energy streams 

carburising furnace, 

base case 

(average energy 

flow in kW) 

Fig. 8: Energy streams 

carburising furnace, 

optimised 

variant (average 

energy flow in 

kW) 

A considerable potential represents the heat recovery 

from the oil bath (absorbs the heat during quenching), 

and also the heat losses from burners even using recuperates 

(the remaining energy content is still high enough). 

Unfavourable conditions like the low temperature level 

of the heat source, the unbalance of energy supply and 

energy demand as well as high investment costs of heat 

recovery systems usually result in long amortisation periods. 

Especially for space heating the seasonal fluctuation of heat 

demand has to be considered. 

As an example the utilisation of energy from flue gas 

(sensible heat loss) from a roller hearth furnace plant with 

a throughput of 3,000 kg/h can be cited. A heat exchanger 

is designed for 225 kW and serves to generate warm water, 



REPORTS 

which is used for space heating but also for the sanitary 

use. 

Regarding the cleaning of the charge heat form 

the oil bath can be used either to heat the cleaning 

agent or to dry the charge. However, a conventional 

heating of the cleaning bath is still recommended to 

maintain a controlled washing agent temperature even 

during start-up of the plant; during steady operation 

the available heat from the oil cooling exceed the 

demand on cleaning agent heating. Fig. 10 shows – 

as an example – the heat recovery from the oil bath of 

a pusher-type furnace plant to heat the cleaning agent 

of a washing unit. Based on the usual electric heating 

and depending on the plant size, amortisation duration 

of approx. 3 years can be reached. Alternatively 

heat from flue gas from burners (sensible heat loss) 

also can be used to heat the cleaning agent. In open 

drying processes the vapour condenser as well as the 

electric heating is obsolete (contrary to closed drying 

processes), however an additional expenditure for an 

oil to air heat exchanger has to be taken into account. 

With this measurement an energy saving of 17-25 kW 

can be achieved. Additionally cooling water can be 

reduces by 20,000 m 3 /yr leading to an amortisation 

time of approx. 3 years. 

CONCLUSION 

Possible efficiency increasing measurements are: 

improved heat insulation, heat recovery from the waste 

gas of burners, utilisation of Endogas – which is currently 

dispatched via a flare – to heat plant units, partial 

substitution of electrical heating and heat recovery 

from the oil bath. 

A process-external utilisation is the waste heat recovery, 

for instance for heating purposes (directly or via 

a heat transformer) or for cooling production (via an 

absorption cycle). These potentials are depending on 

a bundle of site-specific conditions, which have to be 

assessed and carefully considered. 

The process technical total efficiency depends 

on many parameters and the plant throughput has 

a deciding influence; therefore a comparison of two 

plants by means of its efficiencies is only conditionally 

possible. The comparison of efficiencies of the plant 

units with and without efficiency increasing measures 

does not include – by the proper choice of the boundary 

– the losses of the downstream waste heat utilisation 

outside the plant. 

The theoretical saving potential of all proposed efficiency 

increasing measurements amounts up to 61 %, whereby the 

utilisation of the exhausting process gas contributes the predominate 

portion. Because of technical restrictions (transmission 

losses) and economic considerations (amortisation) 

Fig. 9: C-profile in case of a reduced process gas flow 

(reduction of approx. 40 %) 

Fig. 10: Heat recovery from oil bath to heat up aqueous cleaning agents 

usually only half of this benefit can be realised. The theoretical 

saving potential in the given assessment has been expressed 

as natural gas equivalent to enable a direct comparison with 

process-internal efficiency improving measurements, for 

instance with an improved heat insulation. 


59

REPORTS 


Especially for process-external utilisations of energy 

streams it is highly recommended to cooperate with plant 

manufacturer, energy planer and plant operator in an interdisciplinary 

way to ensure an optimum integration in an 

internal operational energy concept of the plant. 

[7] Umweltbundesamt: Aktualisierung von Emissionsfaktoren als 

Grundlage für den Anhang des Energieberichts. Umweltbundesamt, 

Wien. (2007) 

[8] SGL Carbon: Technical Information 05/99/1 E, Wiesbaden. (1999) 

LITERATURE 

[1] Schildler, J.; Zittel, W.: Zukunft der weltweiten Erdölversorgung 

- Überarbeitete, deutschsprachige Ausgabe. Energy 

Watch Group / Ludwig-Bölkow-Stiftung (2008) 

[2] Austrian Energy Agency: Energieflussbild Österreich 2005. 

Wien. (2006) 

[3] Bundesministerium für Wirtschaft und Technologie: Energiedaten 

– nationale und internationale Entwicklung. Berlin. (2008) 

[4] Schmid, C.; Brakhage, A.; Radgen, P.; Layer, G.; Arndt, U.; 

Carter, J.; Duschl, A.; Lilleike, J.; Nebelung, O.: Möglichkeiten, 

Potenziale, Hemmnisse und Instrumente zur Senkung des 

Energieverbrauchs branchenübergreifender Techniken in 

den Bereichen Industrie und Kleinverbrauch. Fraunhofer 

Institut Systemtechnik und Innovationsforschung, 

Forschungsstelle für Energiewirtschaft e.V., Karlsruhe, 

München. (2003) 

[5] Pfeifer, H. (Hrsg.): Taschenbuch industrielle Wärmetechnik – 

Grundlagen, Berechnung, Verfahren. Vulkan Verlag, Essen. (2007) 

AUTHORS 

DI (FH) Jürgen Krail 

Forschung Burgenland GmbH 

Department Energie- und Umweltmanagement 

Pinkafeld, Austria 

Tel.: +43 (0) 3357 / 45370-1328 

juergen.krail@forschung-burgenland.at 

DI Dr. Klaus Buchner 

Aichelin Ges.m.b.H 

Mödling, Austria 

Tel.: +43 (0) 2236 / 23646-384 

klaus.buchner@aichelin.com 

DI Dr. Herwig Altena 

Aichelin Ges.m.b.H 

Mödling, Austria 

Tel.: +43 (0) 2236 / 23646-211 

herwig.altena@aichelin.com 

[6] Umweltbundesamt: PROBAS - Prozessorientierte Basisdaten 

für Umweltmanagement-Instrumente. Umweltbundesamt, 

Dessau-Roßlau. (2008) 

(First published in HTM 5/2010 

(HTM J. Heat Treatm. Mat. 65 (2010) 5, pp. 269-277)) 

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REPORTS 

Energy-optimized route from 

aluminium scrap to extruded 

semi-finished products 

by Günter Valder, Herbert Pfeifer 

Rising energy costs, European CO 2 abatement targets and growing competition from Asia are forcing aluminium extruders 

to investigate energy saving potentials. 14 % energy savings could be realized if all thermoprocessing equipment 

employed met state-of-the-art technology standards. A model greenfield investment is examined by way of example, 

demonstrating the potential for a further 22 % gain in energy efficiency that can become achievable by appropriately 

interlinking processes in the typical melting-holding-homogenizing-preheating-artificial ageing route. 

European semi-finished product manufacturers are 

facing growing competitive pressures in view of the 

EU’s ambitious CO 2 abatement targets and indirect 

energy cost rises. 

German industrial equipment builders in particular have 

been very successfully exporting advanced production 

technology for nearly a decade, especially to Asia. However, 

every export of production equipment involves a transfer 

of know-how; notably joint ventures and input from West 

European consultants drive this effect. In the medium 

term, it stands to be expected that significant quality and 

productivity differences in marketable aluminium semifinished 

products will vanish, all other factors (e.g., material 

used, tooling) being equal, and that Asian manufacturers 

will increasingly gain access to export markets. As a direct 

consequence, sales prices are bound to drop. At the same 

time, European makers of aluminium semi-finished products 

are saddled with relatively high costs of labour, natural 

gas and electricity, not to mention that the projected rise 

in energy costs will be above the rate of inflation. Falling 

prices on the one hand and rising costs on the other will 

result in a lasting profit downturn, narrowing the scope for 

investment. But investment, more than anything, is urgently 

needed to safeguard the necessary head start in innovation. 

All this warrants a closer look at saving potentials. In 

the present article, these are examined with a focus on the 

cost of thermal energy obtained mainly from gaseous fuels 

such as natural gas or propane. 

For all of the above, the task of optimizing operating 

costs does not come as a new challenge to equipment 

builders and manufacturers of aluminium semi-finished 

products. In casthouses and extrusion plants, for instance, 

thermal energy savings of around 14 % would be achievable 

if all thermoprocessing equipment in use today were 

brought up to state-of-the-art technology standards [1]. 

Thus, the political target of cutting CO 2 emissions has 

merely brought the energy efficiency aspect into public 

focus. Maximizing the energy efficiency rates of production 

equipment has been a joint objective, for many years, of 

engineers on both sides, i.e., equipment builders and operators. 

The fact that many existing energy efficiency improving 

solutions are not put into practice becomes evident 

if one considers the determinants of any cost efficiency 

calculation – i.e., the investment costs, which are opposed 

to specific operating cost savings at a given interest rate. 

The zero of the resulting function is the payback period. 

If the investment cost is considered as given, one is 

left with operating cost savings and the payback period 

as parameters for further analysis. This explains why the 

energy efficiency of existing equipment pools falls behind 

what is technically feasible: either the payback period anticipated 

by the investor – usually between one and three 

years – is too short, or else the energy costs are still too low. 

In the following we intend to identify savings potentials 

still realizable in thermoprocess engineering, supposing 

that one had the opportunity to build a new “greenfield” 

continuous casting facility and extrusion plant. Our balance 

envelope is the national economy, i.e., the solution 


61

REPORTS 


Table 1: Thermal energy demand in continuous casting and extrusion plants 

Thermoprocessing plant 

Two-chamber hearth furnace 

State of the art 

“primary exhaust gas utilization” 

Combustion air preheating with 

regenerator, possibly use of organic reaction enthalpies 

Energy demand 

660-700 kWh th / t Al 

Pouring/holding furnace Combustion air preheating with recuperator 30-50 kWh th / t Al 

Homogenizing furnace Combustion air preheating with recuperator 195-205 kWh th / t Al 

Billet heater Combustion air preheating with recuperator and charge preheating 175-215 kWh th / t Al 

Ageing furnace Combustion air preheating with recuperator 75-85 kWh th / t Al 

Thermal energy demand 

1,135-1,255 kWh th / t Al 

approach of substituting thermal with electric energy is 

ruled out because, depending on the electricity mix, this 

would reduce CO 2 emissions only at the plant operating 

level and not for the overall economy. 

THERMOPROCESSING EQUIPMENT IN 

CASTHOUSES AND EXTRUSION PLANTS: 

THE STATE OF THE ART 

Our analysis is based on the present state of the art, in 

that it is assumed that the individual thermoprocessing 

plants employed today have been fitted with energy saving 

technology by now. 

■■ 

Burners run on preheated combustion air, with (central/ 

distributed) regenerators or recuperators providing the 

preheating. 

■■ 

■■ 

■■ 

Burner control systems are designed, on both the component 

and controller side, for broad control ranges (1:10 and 

more) and long ON-times (reducing switching operations). 

The combustion air-fuel ratio is kept as close as possible to 

the stoichiometric one (λ ≈ 1), e.g., with the aid of lambda 

probes. 

Charging patterns and filling levels are adapted to ensure 

that the thermoprocessing plant operates near its design 

point, i.e., at nominal output. 

■■ 

Design measures optimizing the furnace’s efficiency 1 

(insulation structure, avoidance of break-throughs, use 

of suitable seals / gaskets) are in place, and the necessary 

maintenance is carefully performed. 

Table 1 shows the thermal energy demand to be expected 

for an advanced thermoprocessing system if the above 

conditions are met [1]. The figures are related to the mass of 

aluminium being processed. Moreover, it is assumed that 

the system predominantly handles alloys which can be produced 

from returns or externally sourced “post-consumer” 

aluminium. Furthermore, high-strength components requiring 

heat treatment (e.g., T6 temper) are not considered herein. 

1 The furnace efficiency determines what is colloquially referred to as the 

unit’s „idle“ value 

The aim is to optimize the thermal energy demand of 

continuous casting and extrusion lines. By way of solution 

approach, it is discussed below which options exist for 

interlinking thermal processing equipment in such a way 

that the thermal energy, once introduced into the process, 

can be used in as many process steps as possible. 

CASTHOUSE PRODUCTION 

ENVIRONMENT 

The process chain starts with the melting furnace. Given 

that our energy efficiency optimization is to be achieved 

within the prevailing economic balance envelope, as many 

logs as possible must be produced from secondary aluminium, 

i.e., scrap. This task is best accomplished with the 

aid of a two-chamber hearth furnace, Fig. 1, serving as a 

recycling unit. In 2010, European aluminium producers used 

approx. 3.5 t of primary aluminium per tonne of secondary 

aluminium. 

According to the surveys conducted by Quinkertz [2], 

there still exists substantial scope for economically efficient 

recycling of aluminium before the energetic optimum of 

around 75 % is reached, Fig. 2. Such recycling is facilitated, 

aside from its favourable energy balance 2 , by the relatively 

effective waste management systems in place in Europe, 

whereby the availability of suitable scraps can be ensured. 

In the state of the art, two-chamber hearth furnaces 

are commonly fitted with regenerative burners today. 

These require exhaust gas temperatures > 750 °C in order 

to operate efficiently. The relative air preheating rate 

achievable with regenerators is ε = 0.8, i.e., about 80 % 

of the exhaust gas enthalpy can be recovered. Accordingly, 

the combustion air preheat temperature would 

be 800 °C if one assumes a typical heating chamber 

temperature of approx. 1,000 °C, Fig. 3. Downstream 

of the regenerator, an exhaust gas enthalpy of approx. 

200 kWh th /t Al would still be available at a temperature 

of 150 to 250 °C. 

2 The energy demand per tonne of primary aluminium is approx. 13,500 

kWh th+el /t Al [3]. The figure per tonne of secondary aluminium is only a fraction 

thereof, c.f. Table 1. 



REPORTS 

Fig. 1: Example of a typical recycling furnace of Otto 

Junker/THERMCON design 

Fig. 2: Qualitative curve of the total energy costs associated 

with aluminium production (primary and 

secondary), Quinkertz [2] 

The melting furnace is typically followed by a holding 

or pouring furnace. Whether or not such a unit is required 

will depend chiefly on metallurgical factors, but its energy 

demand is almost exclusively a function of transfer losses 

and holding times. As a result, these two latter variables 

should always be minimized. 

Since neither ambient-air burners (which are likewise 

still in use today) nor regenerative burners can optimize 

the energy efficiency of a holding/pouring furnace, the 

use of recuperative burners is recommended. The exhaust 

gas enthalpy downstream of such a unit, amounting to a 

mere 20 kWh th /t Al at approximately 350 to 400 °C, can be 

effectively utilized further only by combining this exhaust 

gas stream with that of the melting furnace. 

A more obvious solution suggesting itself would be 

to interlink the continuous casting system and the downstream 

homogenizing furnace, Fig. 4. 

It is standard practice today to let the logs cool down to 

room temperature before placing them in the homogenizing 

furnace. This method accommodates obvious infrastructure 

and production planning constraints, but there 

are also restrictions imposed by the thermoprocessing 

technology inasmuch as, for reasons of space and time, 

homogenizing furnaces are run with a temperature head 

at least until the start of the soaking phase. A precondition 

for this technique is that the cast aluminium logs enter 

the homogenizing furnace in as isothermal a condition 

as possible. 

However, it would be uncritical, first of all, from a metallurgical 

viewpoint, if this isothermal temperature amounted 

to 300 to 350 °C instead of room temperature, and secondly, 

from a process engineering viewpoint it would not be a 

problem to run a homogenization process with temperature 

heads adjusted to less than ± 10 K. The benefits versus 

drawbacks of the two known operating regimes – i.e., batch 

or continuous operation – must be duly weighed here. At 

first glance, batch operation appears to make more sense 

as the logs from one casting batch would then be homogenized 

in one batch as well. In order to minimize “idle” 

storage times downstream of the caster, thus maintaining 

the baseline temperature as high as possible, it might be 

necessary to provide more annealing and cooling capacity 

than in a conventional production process for an otherwise 

identical annual output. In particular, the cooling chamber 

– inactive at less than 350 °C – might be used as a buffer 

store in this case. 

In return for the higher non-recurrent investment made 

(number of homogenizing systems, space needs), a lasting 

50 % cut in energy consumption would thus be achieved. 

At a charging temperature of 300 °C, one-half of the prior 

energy input – i.e., approx. 100 kWh th /t Al – would be saved 

in a typical homogenizing process. The increased space 

demand remains a disadvantage. 

With the delivery of homogenized logs, the task of the 

casthouse is initially fulfilled. The interface to the downstream 

extrusion pressworks typically consists in a (cold) log 

magazine, given that the typical batch sizes of a (vertical) 

caster and of a batch-type homogenizing process do not 

match typical extrusion batch sizes. 

EXTRUSION PRESS PRODUCTION 

ENVIRONMENT 

However, from the viewpoint of optimizing energy 

demand, it remains to be examined how the manufacturing 

systems of the casthouse and the downstream extrusion 

press can be energetically interlinked in an effective 


63

REPORTS 


Fig. 3: Combustion efficiency (natural gas H, 15 % 

excess air), VDMA [4] 

Fig. 4: Example of a typical billet homogenizing system, 

consisting of two batch furnaces and a cooling chamber 

(Otto Junker design) 

manner. After all, the aluminium logs delivered to the press 

are typically reheated to 480 °C as a first step before any 

metalforming is carried out. If one considers that, for metallurgical 

considerations, the metal would have to cool down 

only to 300 °C instead of to room temperature after the 

homogenizing cycle, the benefits of energetically interlinking 

this latter process to the extrusion plant become 

patently obvious. This approach is not new, yet it has not 

been widely put into practice, and may therefore be well 

worth discussing against the backdrop of ever-progressing 

technological improvement. 

Assuming a capacity of around 4 t/h and an annual 8,000 

operating hours, the casthouse would turn out approx. 

32,000 t of aluminium log stock per year. This volume calls 

for the use of two presses in the downstream extrusion 

plant. In practice it is to be assumed that aluminium extrusions 

will be made both from different alloys (as dictated 

by the subsequent application purpose) and from different 

billet diameters (limitation of the degree of deformation). 

Furthermore, it should be considered that depending on 

the job size, only one log of the same alloy will be needed. 

These boundary conditions give rise to the requirement that 

it must be possible at any time to feed the extrusion press 

with individual billets having a given residual temperature, 

yet differing in diameter and alloy type. 

As a solution to this requirement, the vertical magazine 

shown in Fig. 5 suggests itself. Introduced into the 

market in the last five years, it has been operated exclusively 

as a “cold” storage system until now but allows the 

user to access geometrically and metallurgically different 

logs at any time. 

Developing this cold vertical magazine into a heated or 

“hot-holding” type vertical magazine is a typical engineering 

task, i.e., there exists no obvious feasibility impediment. 

However, it should be noted that the temperature uniformity 

of the “hot held” logs stored in such a magazine 

will not be very good. Frequent access operations (5 to 10 

per hour) and the spatial extension of the vertical magazine 

(= 400 m 2 ) have a negative effect when exhaust gas 

of low dynamic pressure is applied to a large surface area 

as a thermal energy carrying medium in order to keep the 

metal at a desired temperature. From this we can derive 

the boundary condition that the heater installed ahead of 

the extrusion press must be capable of compensating for 

inhomogeneous “incoming” temperatures. Conventional 

heaters in which the metal is exposed directly to the flames 

and, accordingly, is subject to high temperature heads are 

unsuitable for this task due to the risk of metal fusion. A 

convection furnace, on the other hand, is ideally suited 

for this purpose. 

Here the heat transfer takes place at temperatures only 

slightly above the necessary metalforming temperature, 

so that even under unfavourable boundary conditions a 

temperature tolerance of ± 5 K can be guaranteed. From 

the aspect of energy efficiency, too, no other current furnace 

type is more suitable for this task [5]. 

Summing up the above from an energy optimization 

viewpoint, it can be stated that a process in which aluminium 

log stock is preheated from a holding temperature of 

around 300 °C instead of being allowed to cool down after 

the homogenizing treatment can save roughly 60 % of the 

conventional energy input, i.e., approx. 105 to 125 kWh/t Al . 

The convection furnace, Fig. 6, is heated by means 

of recuperative burners and runs at approx. 500 °C. At 

a relative air preheating rate of ε = 0.6 the exhaust gas 

temperature is still around 200 °C, with an exhaust gas 



REPORTS 

Fig. 5: Example of typical vertical magazine for “cold” log 

storage (Otto Junker design) 

Fig. 6: Otto Junker KombiGAS convection furnace (patent 

pending) 

enthalpy amounting to at least 55 kWh th /t Al . Given the 

temperature downstream of the recuperator, this exhaust 

gas is no longer useful for heating the magazine. It should 

therefore be fed into the interlinked exhaust gas collection 

system of the casthouse. 

The above implies that the vertical magazine must be 

held at the specified high temperature using exhaust gas 

from the homogenizing furnace. The latter still provides an 

exhaust gas enthalpy of around 85 kWh th /t Al , even when 

charged with logs of “as cast” temperature. However, the 

recuperator should be designed for an exhaust gas temperature 

of 320 °C so that the energy loss of the vertical 

magazine can be covered. In theory, this exhaust gas with 

its enthalpy of around 60 kWh th /t Al might then be fed into 

the existing interlinked exhaust air collection system at a 

temperature of 300 °C. 

This leaves us to consider the aging furnace, Fig. 7. It 

would appear plausible at first to assume that the product 

temperature at the exit of the extrusion press (approx. 500 

to 550 °C) makes hot-charging of the aging furnace a mandatory 

requirement. Upon closer inspection, however, this 

optimization approach does not turn out to be effective. 

For metallurgical reasons the extruded sections must often 

be cooled at once and/or stretched at some later point. 

For this reason, the extrusions are stacked into baskets in 

a cold state downstream of the so-called runout system 

and fed to the aging furnace. 

There, the aluminium extrusions must be heated to 

185 °C and are held at that temperature for several hours. 

Given the low process temperatures and the resulting risk 

of falling below the dew-point (= staining), artificial ageing 

furnaces are indirectly fuel fired, usually by means of 

ambient air burners. The exhaust gas temperature downstream 

of such a burner may amount to 280 °C, depending 

on the radiant tube surface watt density. For reasons 

of energy efficiency optimization, recuperative burners 

are the equipment of choice here because on principle, 

the energy efficiency will increase the more, the closer 

the link between the primary process and the efficiency 

boosting measure. Downstream of the recuperator, the 

exhaust gas temperature cannot be expected to exceed 

approx. 120 °C. It is true that in absolute terms the energy 

gain is only 10 kWh th /t Al , yet this equals more than 10 % of 

the prior energy input. 

Any further utilization of the exhaust gas – e.g., in the 

proposed interlinked exhaust gas system – would not 

make sense, given the gas temperature downstream of 

the recuperator. 

Fig. 7: Example of a typical artificial aging furnace (Otto 

Junker design) 


65

REPORTS 


Table 2: Thermal energy demand in the casthouse and extrusion press shop following optimization 

Thermoprocessing plant Savings Optimized energy demand 

Two-chamber hearth furnace 30 kWh th / t Al 630-670 kWh th / t Al 

Pouring/holding furnace none 20-40 kWh th / t Al 

Homogenizing furnace 100 kWh th / t Al 95-105 kWh th / t Al 

Billet heater 105-125 kWh th / t Al 70-90 kWh th / t Al 

Ageing furnace 10 kWh th / t Al 65-75 kWh th / t Al 

Thermal energy demand 245-265 kWh th / t Al 880-980 kWh th / t Al 

With all fuel-heated thermoprocessing equipment 

thus analysed, the effect of the interlinked exhaust gas 

handling system can now be estimated. In all, an exhaust 

gas enthalpy of 335 kWh th /t Al , at a temperature of approx. 

250 °C (with adiabatic mixing), is available from the recycling 

furnace, the holding/pouring furnace, the heated 

vertical log magazine, and the billet heater. 

Only 30 kWh th /t Al are needed to preheat and dry the 

scrap charge for the recycling furnace at 100 °C. Instead 

of storing incoming external and home scrap in stockpiles, 

it would be necessary to create a scrap bunker 

heated with the energy stream of the interlinked exhaust 

gas handling system. One possible solution approach 

might be to provide a system of circulating “pick-andplace” 

charging bins; these would be loaded with incoming 

scrap in a runaround arrangement, parked in the 

heated bunker by automatic control, and withdrawn as 

needed or after a defined dwell time for loading of the 

recycling furnace. 

POSSIBLE OUTCOME 

Various approaches have been discussed for reducing the 

energy demands of the casthouse and extrusion pressworks: 

■■ 

spatial combination of the casthouse and extrusion 

press plant; 

■■ 

creation of an interlinked exhaust gas handling system 

for preheating scrap to 80 °C; 

■■ 

start of the homogenization cycle from 300 °C instead 

of from room temperature; 

■■ 

start of billet heating from 300 °C instead of from room 

temperature; 

■■ 

use of recuperative burners in the aging furnace. 

The measures described above yield savings of 245 

to 265 kWh th /t Al , equivalent to 22 % (Table 2). At a 

mean EU28 industrial gas price of 0,039 €/kWh th [6] 

and the assumed annual output of 32,000 t, energy 

savings worth between 305,000 and 330,000€ can be 

achieved each year in the casthouse and in the extrusion 

pressworks. 

CONCLUSION 

Thermal energy saving potentials were analysed for the 

hypothetical case of a “greenfield” investment. It emerged 

that a number of measures are available when projecting 

a new plant. Still, higher investment costs may have to be 

anticipated in individual cases, and their cost efficiency may 

be contingent on the acceptability of extended payback 

periods. Otherwise, the necessary technology changes 

would only be forced by (still) higher energy costs. The 

first of these approaches is preferable, since energy savings 

reduce demand and prices. 

At the same time, it becomes clear that these doubtlessly 

existing potentials can only be tapped via an interdisciplinary 

cooperation between diverse fields of engineering 

science. On the other hand, one must concede that restrictions 

apply at today’s sites which allow only some of the 

above measures to be implemented in practice. 

For the sake of completeness, one key aspect should 

not remain unmentioned. The above discussion implies 

that the full 32,000 t of aluminium p.a. can be turned 

around in the process chain (i.e., from the recycling furnace 

to the aging furnace) without any loss. This, of 

course, is unrealistic. In fact one would typically have 

to charge more than 42,000 t of aluminium into the 

recycling furnace in order to be able to sell 32,000 t of 

extrusions. More than 30 % of the charge will normally 

end up in the cycle again as melting loss, transfer loss, 

log heads, billet end material, extrusion butts, extrusion 

scrap and rejects. In many cases, it is this very fact which 

justifies the operation of a casthouse in conjunction 

with an extrusion press shop. In that regard, productivity 

improvements too can still go a long way towards 

reducing energy demand. 

LITERATURE 

[1] Valder, G.: Ermittlung des Energieeinsparpotenzials und 

Bestimmung von CO 2 -Produktbenchmarks bei der Herstellung 

stranggepresster Halbzeuge aus Sekundäraluminium 

[Investigating the energy saving potential and determina- 



REPORTS 

tion of CO 2 product benchmarks in the manufacture of 

extruded semi-finished products from secondary aluminium], 

doctorate thesis, Technical University of Aachen 

(RWTH), 2011, p. 120 

[6] Destatis: Daten zur Energiepreisentwicklung [Energy price trend 

data], Statistisches Bundesamt, Wiesbaden [German Federal 

Office of Statistics, Wiesbaden], https://www.destatis.de/.../ 

EnergiepreisentwicklungPDF_5619001.pdf, 11/2012, p. 22 

[2] Quinkertz, R.: Optimierung der Energienutzung bei der Aluminiumherstellung 

[Optimizing energy use in the production 

of aluminium], doctorate thesis, Technical University of 

Aachen, 2002, p. 78 

AUTHORS 

[3] Hajek, A.: Entwicklungen auf dem Rohstoffmarkt [Trends in 

the raw materials market], Forum für Zukunftsenergien e.V. 

[Future Energies Forum], 23 rd session of 16 March 2005 

[4] VDMA: Leitfaden Energieeffizienz von Thermoprozessanlagen 

[Guide on the Energy Efficiency of Thermoprocessing 

Equipment], VDMA publication, 3/2009, p. 19 

[5] Gauvain, M. et al.: Otto Junker nimmt neuartige hocheffiziente 

Bolzenerwärmungsanlage bei Sapa Offenburg erfolgreich 

in Betrieb [Otto Junker successfully commissions a 

new type of high-efficiency billet heating unit at Sapa Offenburg], 

Aluminium International, 5/2012, pp. 62-66 

Dr.-Ing. Günter Valder 

Otto Junker GmbH 

Simmerath, Germany 

Tel.: +49 (0) 2473 / 601-328 

va@otto-junker.de 

Prof. Dr.-Ing. Herbert Pfeifer 

RWTH Aachen 

Institute of Industrial Furnace Construction 

and Heat Technology 

Aachen, Germany 

Tel.: +49 (0) 241 / 8025-935 

pfeifer@iob.rwth-aachen.de 

Handbook of Aluminium Recycling 

Mechanical Preparation | Metallurgical Processing | 


Order at: 

Tel.: +49 201 82002-14 

Fax: +49 201 82002-34 

bestellung@vulkan-verlag.de 

The Handbook has proven to be helpful to plant designers and operators 

for engineering and production of aluminium recycling plants. The book 

deals with aluminium as material and its recovery from bauxite, the 

various process steps and procedures, melting and casting plants, metal 

treatment facilities, provisions and equipment for environmental control 

and workforce safety, cold and hot recycling of aluminium including 

scrap preparation and remelting, operation and plant management. Due 

to more and more stringent regulations for environmental control and 

fuel efficiency as well as quality requirements sections about salt slag 

recycling, oxy-fuel heating and heat treatment processes are now incorporated 

in the new edition. The reader is thus provided with a detailed 

overview of the technology of aluminium recycling. 

Editor: C. Schmitz 

2 nd edition 2013, approx. 500 pages in colour, with interactive eBook (online read access), 

hardcover 

ISBN: 978-3-8027-2970-6 

€ 130,00 

Order now! 

KNOWLEDGE 3-2013 heat processing FOR THE 

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67

REPORTS 

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REPORTS 

Microwave heating – practical 

examples 

by Ivan Imenokhoyev, Peter Wübben 

Since approx. 50 years microwave heating has been available for industrial use. For showing the advantages of this 

technique, the theory of microwave heating will be explained and the practical application will be demonstrated with 

some selected examples. The recent article gives an overview of the possible kinds of industrial microwave heating and 

the advantages of it against conventional heating. 

Microwave heating systems exist in many different 

industrial versions. Besides the classical chamber 

systems the heating with microwave is used in 

continuous drying and heating plants. Many years of experience 

in the microwave field and innovative ideas are the 

basis for the microwave units from Linn High Therm (LHT). 

The possible ways of applying this technology to drying 

and heating processes are as many as in conventional 

thermal process techniques. The treatment of materials 

by microwaves shows a number of promising advantages 

against conventional heating technologies, i.e. improved 

product quality, reduction of process time, saving of energy 

and energy cost by better efficiency, reduced environmental 

pollution, lower plant costs and higher production 

flexibility [1-5]. 

Microwave heating is a process in which electromagnetic 

energy with a frequency of 0.3 – 3 GHz penetrates 

a material and where the electromagnetic wave, or rather 

wavelengths in a range of 1 m to 1 mm, is converted into 

heat. For microwave applications mainly four ISM frequencies 

(Frequencies for Industrial, Scientific and Medical radiofrequency 

equipment) are available. The highest frequency 

possible is 28 or rather 30 GHz, for which an industrial and 

economic use is not yet visible. 

The low frequency of 0.915 GHz requires some technical 

effort which is only justified for some special cases. The 

economically most relevant frequency is 2.45 ± 0.050 GHz 

which is used worldwide by household microwaves. From 

the point of view of microwave thermal process technology 

the SHF (super high frequency) band with a frequency of 

5.8 GHz ± 0.075 MHz is useful for some industrial applications [5]. 

Before having a closer look at the principle of microwave 

technology, the conventional heating process is considered. 

In this heating method resistance or infrared heating 

elements, which are close to the material needed to be 

heated, are serving as the heat source. Via heat radiation 

and convection this energy is transferred to the outer surface 

of the material and has to migrate into the interior to 

effect a complete warm up. The thermal conductivity and 

specific heat capacity are the most important factors for 

this heating process [3]. 

Sensible materials due to circumstances may not allow 

high temperatures and if the material additionally has a 

low thermal conductivity a long process time is inevitable. 

This leads to a narrow window during production of certain 

products with conventional heating techniques. To bypass 

these confines the laws of physics have not to be rewritten 

but “high frequency technology respectively radar 

engineering” only has to attract more interest. 

In case of microwave drying, the inverse temperature profile 

is advantageous, as a higher vapour pressure develops 

inside the material and drying is effected from the inside to 

the outside. In the colder outer layers, a part of the steam 

condenses and keeps the surface humid and permeable 

until there is no more steam from the inside and the surface 

consequently starts to dry, too. As water generally converts 

the most microwave energy due to its high loss factor, lower 

energy transformation (microwaves radiation without being 

weakened) is effected depending on the drying substance 

and drying rate of the inside although this energy can be 

used in other areas. This way, effective drying by removing all 

water nests is possible. Because of the different energy input 

of the materials to be dried, in principle different processes 

are possible although there is no essential difference above 

a humidity content of approx. 15 wt.-%. In this case, water 

determines the process. In the range from 5 – 15 wt.-%, the 


69

REPORTS 


Table 1: Overview of test for microwave treatment of leguminous plants 

Technical Parameters / 

Description 

Value 

Comments 

Test material leguminous plants Grain size 3-5 mm; filling height 35-60 mm 

Start humidity of material approx. 6.73 wt.-% Measured with analysis balance Sartorius MA 40 

End humidity of material approx. 5.7 wt.- % Measured with analysis balance Sartorius MA 40 

Insects in material 

Existing 

In 5 plastic bags all 16 insects were after visual control estimated 

to be killed. 

On the next day 1 insect became alive. Totally appr. 6.25 % 

(1 insect) from 16 insects survived the microwave treatment 

and the rest 93.75 % (15 insects) were killed. 

Ambient room temperature 27.3 °C Measured value from resistance thermometer PT1000 

Material inlet temperature 27.2 °C Measured value from resistance thermometer PT1000 

Material outlet temperature see Fig. 2 & Fig. 3 Measured with PT1000 and IR-heat picture camera FLIR, USA 

Microwave power 68 kW 85 Magnetrons a 800 W in operation 

Hot air power 24 kW 2 electrically heated hot air zones 

Temperature of hot air 95 °C Pre-set value at temperature controller 

Temperature of air on output 47 °C Measured value of resistance thermometer PT1000 

Total power 92 kW 68 kW of MW-power with 24 kW of hot air power 

Belt speed approx. 1.07 m/min Measured value 

Dwelling time 15.23 min Calculated value 

Cycle time approx. 57.58 min Measured value 

Mass of material 2,100 kg Measured value 

Mass throughput approx. 2,188 kg/h Calculated value 

drying substance itself can play a more and more important 

role. If the material itself can transform microwave energy into 

heat, the temperature of the material can increase although 

the temperature dependence of the dielectric constant determines 

the process. In case of certain chemicals, the chemically 

bonded water can be split off that way. Below 5 wt.-% humidity, 

microwave drying can become ineffective with decreasing 

humidity content. However, it is highly recommended to 

examine the material before for ensuring that the necessary 

temperatures can be reached [5]. 

Fig. 1: Microwave belt drier MDBT 70+24/1040/210/16300, 

(installed Microwave power 70 kW, hot air power 

24 kW, throughput approx. 2,000 – 3,000 kg/h) 

Fig. 2: Surface temperature distribution at a long 

time test measured with thermal IR camera 



REPORTS 

At the beginning of the 90’s, the company 

Linn High Therm started their activities 

in the area of microwave heating in cooperation 

with Riedhammer. In order to meet 

the demand for industrial dryers, a modularly 

designed microwave continuous belt dryer 

was developed. 

Due to the easy and flexible concept of 

modular design, it was possible to manufacture 

a cost-effective microwave continuous belt 

dryer (MDBT) which can be used for various 

applications. It is a universal device which can 

be adapted to various applications e.g. for drying 

wood, ceramics, chemicals, food, building 

materials, for hardening of fibre reinforced composite 

materials (GFC/CFC) and more. Furthermore 

the microwave heating principle can be 

used for defrosting, calcining, hardening, tempering 

and acceleration of chemical reactions. 

Some practical examples of microwave 

treatment are listed below which describe the 

functional principle and illustrate the effectiveness 

of industrial microwave plants in detail. 

MICROWAVE TREATMENT OF 

LEGUMINOUS PLANTS 

Table 1 gives an overview about the microwave 

treatment of leguminous plants i.e. beans, peas. 

The microwave treatment (Fig. 1) is used for the 

reduction of germs, killing of insects without 

the danger of damaging the product, influencing 

taste or optical appearance while increasing 

durability. 

The effectiveness of microwave treatment 

and the resulting product temperature can be 

seen on thermal IR figures. Fig. 2 shows a typical 

temperature distribution of a long time test. A 

continuous temperature measurement during 

microwave treatment in the product is possible 

via PT1000 resistance elements or a fibre optical 

measurement system. Fig. 3 shows the measurement 

results from a temperature measurement 

with PT1000 resistance elements. 

MICROWAVE TREATMENT OF 

SALT 

As test equipment the microwave belt drier 

MDBT 9/2,45–1,6/5,8+3/640/1650 was used 

(Fig. 4). The belt speed of approx. 0.3 m/min 

was kept constant during the microwave treatment 

of salt. The humidity of a small sample of 

approx. 10 – 13 g was measured by a humidity 

balance analysis at test start and end. 

Temperature in °C 

80 

70 

60 

50 

40 

30 

Long 2me test 

20 

0 10 20 30 40 50 60 

Time in minutes 

Temperature le4 

Temperature middle 

Temperature right 

Fig. 3: Temperature vs. time in material during long time test, measured with 

PT1000 

Fig. 4: Microwave belt drier MDBT 9/2,45–1,6/5,8+3/640/1650 

Fig. 5: Placement of fibre optical sensors 


71

REPORTS 


160 

Microwave treatment of salt 

150 

140 

130 

120 

Temperature in °C 

110 

100 

90 

80 

70 

60 

Temperature le5 

Temperature middle 

Temperature right 

50 

40 

30 

20 

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 

Time in minutes 

Fig. 6: Temperature course in salt measured with fibre optical sensors 

The total microwave power was approximately 10.6 kW. 

The temperature of the bulk material was measured by a 

fibre optical temperature measurement system. Three fibre 

optical sensors were placed in the material according to 

Fig. 5. The measured results are shown in Fig. 6. Additionally 

the surface temperature was controlled by pictures 

from a thermal IR camera. 

For the technical process it is important to reach a 

high degree of efficiency and a homogenous electromagnetic 

field. This is realized by nine 900 W standard 

magnetrons which do not only have a long lifetime but 

also significantly lower maintenance and repair costs. All 

materials which are in contact with the product are made 

of stainless steel, Teflon or silicone. During design phase, 

it was also put emphasis on the fact that all components 

can be cleaned, maintained and changed easily. 

CONCLUSION 

This article gives an overview of innovative microwave 

heating plants for applications in different industrial 

fields. They have been developed for laboratory and 

productions by Linn High Therm based on many years’ 

experience and are used successfully worldwide. In 

specific examples it is shown how the effectiveness of 

microwave heating can be controlled. 

LITERATURE 

[1] Feher, L.: Energy Efficient Microwave Systems, Springer Verlag, 

2009 

[2] Imenokhoyev, I.: Computergestützte 3D-Modellierung von 

Mikrowellen-Erwärmungsanlagen. Berichte aus der Verfahrenstechnik. 

Aachen: Shaker Verlag, zugl. Freiberg, TU Bergakademie 

Freiberg, Dissertation, 2007 

[3] Wübben, P.; Kintsel, N.: Sparsam erwärmen mit Mikrowellen. 

In VDMA-Nachrichten Mai/2011 VDMA Verlag GmbH, Frankfurt 

am Main 

[4] Imenokhoyev, I.; Windsheimer, H.; Waitz. R.; Kintsel, N.; Linn, 

H.: Mikrowellenerwärmungstechnik: Potentiale und Grenzen. 

In cfi /Ber. DKG 89 (2012) No. 11-12., S. D 19-D 27 

[5] Imenokhoyev, I. et al.: Microwave Heating Technology: Potentials 

and Limits. In cfi/Ber. DKG 90 (2013) No. 4, S. E 41-E 49 

AUTHORS 

Dr. Ivan Imenokhoyev 

Linn High Therm GmbH 

Eschenfelden, Germany 

Tel.: +49 (0) 9665 / 9140-48 

imenokhoyev@linn.de 

Dr. Peter Wübben 

Linn High Therm GmbH 

Eschenfelden, Germany 

Tel.: +49 (0) 9665 / 9140-62 

wuebben@linn.de 


Gas Quality 

REPORTS 

Changing natural gas qualities: 

impact on industrial gas-fired 

applications 

by Jörg Leicher, Anne Giese 

In the years to come, the markets for natural gas, both in Germany and in Europe in general, will see significant changes. 

The harmonisation of gas quality standards within the EU, a globally changing supply situation and an increasing integration 

of gases from renewable sources (e.g. biogas or power-to-gas) will lead to a gas grid in which end users will be 

confronted with greater variations in gas quality. While this evolution of German and European gas grids offers a number 

of economical and ecological advantages, it may pose a challenge to end users, especially in the industrial sector. 

Natural gas markets, both on the German and 

European level, are changing for a variety of reasons. 

The depletion of mature gas fields and their 

replacement by gas production in different geographic 

locations (mostly Russia and the Middle East, transported 

to Europe via pipelines); increased cross-border transport 

of natural gas and the rapidly developing global market for 

liquefied natural gas (LNG) change the economic boundary 

conditions for European gas suppliers and distributors. It 

is also expected that in the years to come, combustible 

gases from renewable sources (e.g. biogas, SNG or hydrogen 

generated by electrolysis powered by excess wind or 

solar power) will be fed into the gas distribution grid to a 

greater extent than today. 

Another factor is that the European Commission aims to 

harmonize gas quality standards within the EU in order to 

liberalise the European natural gas market and remove trade 

obstacles. To this purpose, it issued a mandate (M/400) to 

the European Committee of Standardization (CEN, Comité 

Européen de Normalisation) in 2007 [1] to propose common 

European gas quality standards. These standards will probably 

be published in 2014/15. A first step in this direction was the 

establishment of the EASEE-gas group by the European Association 

for Streamlining Energy Exchange (EASEE). This group 

produced a gas quality specification [2] which is to facilitate 

cross-border natural gas transfer without compromising the 

operability of gas appliances. It is generally expected that 

this specification will form the basis of the mandated CEN 

standard for natural gases with high calorific values (H-Gas). 

Natural gas with lower calorific values, so-called L-Gas, 

while still being distributed in some regions of Europe 

(parts of Germany, the Netherlands, Belgium and France) 

is no longer considered relevant for a European harmonisation 

effort since the respective gas fields are expected to 

cease production within the next few years. 

Despite European efforts to harmonise natural gas 

qualities within the EU in recent years, gas qualities for 

the moment are still being regulated on a national level 

which makes the quantification of natural gas qualities 

rather intransparent [3]. As it is not practicable to prescribe 

fixed chemical compositions for natural gases, the most 

common approach to quantify fuel gas quality is to use 

a set of characteristic parameters. The most important 

parameter in this context is the so-called Wobbe Index W S 

which is calculated by the higher calorific value H S and the 

specific density d: 

The Wobbe Index is the primary parameter for fuel gas 

interchangeability. In theory, a gas-fired device can switch 

from one fuel gas to another without modifications as long 

as the two fuel gases have similar Wobbe Indices. 

However, Wobbe Indices do not use the same reference 

temperatures for energy and volume related properties 

everywhere. EASEE-gas [2] for example uses 25 °C and 0 °C 

respectively, as does the German Code of Practice DVGW 


73

REPORTS 

Gas Quality 

Fig. 1: Distributed natural gases in Germany and limits imposed by 

DVGW G260 [5] 

Fig. 2: Legal and typical gross wobbe index ranges for H-Gases 

found in eight EU member states [8], [11] 

G260 [5]. In the UK, both energetic and volumetric properties 

are referenced to a temperature of 15 °C, while in the 

US, the unit [BTU/scf] is used for the Wobbe Index instead, 

with a reference temperature of 60 °F (= 15,56 °C) for both 

energy and volume [6]. In all cases, a reference pressure of 

1.01325 bar is used. An international convergence of the 

quantification of fuel gas quality is not in sight. 

It should be pointed out that from the perspective of 

many industrial end users of natural gas, the Wobbe Index 

is only of minor importance anyway. For the design of 

industrial burners and furnaces, the lower calorific value 

H i plays a much bigger role. Also, there are many applications 

where the Wobbe Index alone is insufficient to 

capture crucial aspects of combustion behaviour, such as 

combustion dynamics or ignition behaviour in gas turbines 

and gas engines. 

While the Wobbe Index is the most common regulated 

property in the context of gas quality, there are a number 

of other constraints imposed on distributed natural gas by 

national authorities, for example oxygen and sulphur contents 

or dew points. These regulations vary from country 

to country. The UK’s Gas Safety (Management) Regulations 

GS(M)R also acknowledge that the Wobbe Index alone cannot 

comprehensively describe combustion behaviour and 

thus introduce additional limiting parameters such as the 

Incomplete Combustion Factor (ICF) and the Sooting Index 

SI with respective threshold values. On the other hand, they 

do not pose an upper limit for the higher calorific value, 

which other national regulations do. 

Overviews of the different gas quality specifications in 

Europe can be found in [7] and [8] for example, while [9] 

also provides information on the situation in the Americas 

and Asia as well as more details on the various methods 

used to quantify gas quality. 

Fig. 1 shows a number of distributed natural gases in 

Germany along with the legal limits imposed by DVGW 

Code of Practice G260 which regulates gas qualities in the 

German distribution grid [5]. It is obvious that currently, 

only a relatively small fraction of the permissible ranges 

of L- and H-Gas is actually being used. This observation 

is not necessarily valid for other European countries, as is 

illustrated in Fig. 2. It shows a comparison of the legally 

possible H-Gas ranges in various EU member states as well 

as the EN437 [10] and EASEE-gas minimum and maximum 

values, re-calculated for a common reference temperature 

of 15 °C [11]. These eight countries together account for 

about 84 % of Europe’s natural gas consumption and were 

the focus of a MARCOGAZ study [8]. According to [12], permissible 

Wobbe Index variation ranges for H-Gas in Europe 

are between ± 3.7 % and ± 10.2 %, while the actual spread 

is between ± 0.7 % and ± 3.2 %. Other sources, e.g. [13], 

give average fluctuations of the Wobbe Index in Germany 

of about 2 % around the mean values. 

The figure also shows the discrepancies between legally 

possible minimum and maximum Wobbe Indices in different 

countries. If the European harmonisation of natural gas 

qualities comes into effect as planned (see [14] for a possible 

European harmonisation roadmap), some countries with 

traditionally narrow Wobbe Index ranges such as Denmark 

or the United Kingdom will have to accept a greater variety 

of natural gas qualities in their national transmission grids, a 

fact which is viewed critically at least in the UK [15]. Of course, 

there are other countries who have to reduce the possible 

Wobbe Index range. At the moment, there is a discussion 

if the EU actually profits from an overall harmonisation of 

gas quality standards [3], or if the additional cost and risks 

outweigh the potential benefits [16]. 


Gas Quality 

REPORTS 

The most important point in this context is, however, 

that up to now, many European end users of natural gas 

could assume a relatively constant fuel quality for their 

applications at a given location. This fact is especially relevant 

with regards to industrial firing systems: such systems 

have to safely operate at high efficiencies, with low pollutant 

emissions and optimum product quality in the case of 

gas-fired manufacturing processes. These plants are usually 

designed for one specific site with a given set of operating 

conditions; each plant is unique and tuned for optimum 

performance using the locally available natural gas composition. 

Domestic gas-fired appliances, on the other hand, are 

produced in greater numbers and thus may or may not be 

calibrated in the factory, using a well-defined reference gas, 

a practice which is not technically feasible for applications 

with higher thermal loads. Therefore, industrial combustion 

processes are expected to be more susceptible to local gas 

quality fluctuations. 

In 2011, about one third of all natural gas sales in Europe 

went into the industrial sector, with another 29 % being 

used for power generation applications (cf. Fig. 3) [17]. The 

use of natural gas in the industrial sector is very diverse: gas 

combustion is used to provide process heat for manufacturing 

purposes, from melting and heat treatment applications 

in ferrous and non-ferrous metallurgy to glass, ceramics 

or plastics production, to name just a few. In the chemical 

industry, natural gas serves both as fuel and feedstock, for 

example for hydrogen or fertilizer production processes. 

In thermal process engineering alone, there is a great 

variety of different processes which utilize natural gas. 

Some of them have proven to be quite resilient to changes 

in fuel gas quality; some, on the other hand, are known to 

react very sensitively to even small variations in the chemical 

composition of the fuel. 

While there already are investigations on the impact of 

changing gas qualities on residential appliances (for example 

the EU-funded GASQUAL campaign [18, 19], or similar studies 

in the UK [20] and California [21]), the effects of changing 

natural gas qualities on industrial firing systems have yet to 

be investigated in detail. But even in the field of residential 

gas-fired appliances, there is no consensus with regards to 

the effects of varying natural gas qualities [22, 23]. 

IMPACT OF COMPOSITION CHANGES IN 

NATURAL GAS ON INDUSTRIAL 

COMBUSTION PROCESSES 

The discussion about the impacts of varying natural 

gas qualities on both residential and industrial firing 

processes is driven by two different points of view. Gas 

suppliers focus on distributing and supplying natural 

gas within the national legal limits as economically as 

possible for a wide variety of end users with residential, 

commercial and industrial applications. Their interest 

is to avoid additional cost for conditioning natural gas 

and to maintain their independence from only a few 

gas-producing countries. Due to political and economic 

boundary conditions, they have to cope with the unbundling 

of supply and grid operations, while also integrating 

an increasing amount of combustible gases from 

renewable sources into their infrastructure [13, 24]. From 

a purely economic point of view, the harmonisation of 

gas qualities is certainly worthwhile, especially to encourage 

international trading of natural gas [3]. 

Some gas suppliers stress that it is the responsibility of 

both manufacturers and operators of gas-fired devices, no 

matter if they are for residential, commercial or industrial 

purposes, to ensure that their equipment operates safely 

and efficiently within entire range of the legally possible 

limits [13]. Consequently, they demand the installation of 

advanced measurement and control technology to detect 

and compensate for possible composition changes in the 

natural gas on-site. In their eyes, it is the process operator’s 

responsibility to be able to handle any natural gas quality 

as long as it conforms to legal standards. Others see the 

reliance of certain industrial manufacturing processes on 

a very constant fuel quality as a business opportunity and 

offer specific services to these customers [25, 26]. In certain 

isolated markets, Japan for example, suppliers even condition 

their natural gas to a much greater extent than what 

is legally required specifically to satisfy the needs of their 

industrial customers, for example in the glass and metallurgical 

industries [27]. 

While it is usually sensible both from an economical 

and operational point of view for gas suppliers to avoid 

conditioning their gas to a very narrow band of fuel qualities, 

industrial operators on the other hand have a vested 

Fig. 3: Natural gas sales in Europe by sector in 2011 [17] 


75

REPORTS 

Gas Quality 

Fig. 4: Measurement of the main components of natural gas near Leipzig (end of 2011) [29] 

interest in exactly that: reliably constant fuel gas characteristics 

in their plant. This is a situation that many of them 

have enjoyed over the last decades. 

For industrial end users, the Wobbe Index is only of 

minor importance as they usually do not have to deal 

with matters of natural gas quality and interchangeability. 

Instead, the lower calorific value and sometimes even the 

actual chemical composition is required to design burners 

and furnaces [9, 24]. In thermal processing applications 

where flames are used as tools to modify material properties, 

the chemical composition is of particular importance 

as it will influence flame lengths and heat transfer within 

the furnace. These processes tend to be especially vulnerable 

to sudden changes in natural gas quality. The same 

is valid for the chemical industry which uses natural gas 

as a feedstock [9, 26]. 

For manufacturing purposes such as melting or heat treatment, 

it is necessary to operate thermal processes in such a 

way as to achieve optimum performance with regards to 

efficiency, pollutant emissions and product quality. Of course, 

safe operation of the plant is always of paramount importance. 

In response to this challenge, different industries developed 

different solutions. Fluctuating fuel gas qualities only add 

another layer of complexity to an already often difficult task. 

Among thermal processing applications, glass and 

ceramics production are acknowledged by many (e.g. [9, 

24, 26, 28, 29]) to be especially vulnerable to fuel gas quality 

fluctuations, since these manufacturing processes are 

known to be very sensitive to even small changes in their 

operating conditions. In 

ceramics production, even a 

change of the furnace temperature 

of only a few Kelvin 

can lead to a discoloration 

or a reduced quality of the 

glaze [30]. 

Nevertheless, the German 

glass industry, for 

example, managed to 

reduce the specific energy 

consumption per ton of 

produced glass from about 

15 MWh/t in 1920 by 600 % 

to about 2.5 MWh/t in 1990, 

a value that has remained 

constant since then [31]. 

Despite the very sensitive 

nature of the glass melting 

process, research, development 

and continuous 

optimisation efforts led 

to a significant increase in 

overall process efficiency at 

constant or improved product quality. The price for this, 

however, is an even more pronounced sensitivity of the 

production process to changes in operating conditions 

[31]. A recent poll among German glass manufacturers 

shows that about 50 % experienced production problems 

due to fluctuating natural gas quality [32]. Glass production, 

especially glass melting, reacts strongly to even small 

changes in furnace atmosphere and temperature, both 

with regards to glass quality, but also with regards to NO X 

emissions. Since glass melting furnaces operate with very 

high air pre-heat temperatures (1,300 °C - 1,400 °C are common) 

at near-stoichiometric conditions, they run the risk of 

high NO X emissions anyway, so that even small fluctuations 

may push them beyond the legal emission limits. Feeder 

burners are also known to react strongly to such changes. 

Fig. 4 shows measurements of the natural gas composition 

at a thermal processing plant near Leipzig, Germany [29]. 

It can be seen that the methane concentration fluctuates 

between a minimum of about 89 vol.-% and a maximum 

of almost 98 vol.-%. The variations at this site were strong 

enough to motivate plant operators to invest in a gas-phase 

chromatographer for online fuel quality monitoring. 

DVGW (Deutscher Verein des Gas- und Wasserfachs, The 

German Technical and Scientific Association for Gas and 

Water) is currently funding a research project which investigates 

the impact of natural gas variations on various 

industrial combustion applications, among them steam 

generators and glass melting furnaces. Using CFD simulations 

of a typical regenerative glass melting furnace with 


Gas Quality 

REPORTS 

a variety of G260-compliant test gases, the impacts of 

changing fuel gas qualities on the glass melting process 

were investigated in a number of different scenarios. It 

could be shown that different chemical compositions can 

have a profound impact on the operation of the furnace. 

Velocities, temperature distributions and pollutant emissions 

(NO X ) were strongly affected by changing fuels, as 

was the heat influx into the glass melt. Since the chemical 

composition of the fuel determines both the lower 

calorific value and the minimum air requirements, composition 

changes will impact both the energy balance 

and the stoichiometry of the furnace if not detected and 

adequately compensated. In a worst-case scenario, a switch 

from the reference fuel gas to a gas with a higher calorific 

value without a subsequent modification of the air volume 

flow led to sub-stoichiometric conditions within the 

furnace: large amounts of toxic carbon monoxide as well 

as hydrogen were produced and entered the regenerator. 

As regenerative glass melting furnaces periodically reverse 

the flows in the furnace, this could lead to an uncontrolled 

post-combustion in the regenerator head, damaging the 

regenerator. But even if the air flows are adapted to ensure 

constant air ratios, changes in the fuel compositions cause 

significant differences in the furnace temperatures, flame 

lengths and heat fluxes into the glass melt. In one simulated 

case, the temperature on the back wall of the simulated 

furnace rose to potentially dangerous levels. Measurements 

carried out at semi-industrial test rigs also showed the 

impact of changing fuel gas compositions on temperatures 

and pollutant emissions, even at constant burner loads 

and air ratios. Discussions with operators of glass melting 

furnaces confirm these findings. 

As thermal processing applications are subject to 

increasingly strict regulations with regards to pollutant 

emissions, unnoticed fluctuations in the natural gas composition 

may well lead to operational issues in this context, 

a serious problem for both operators and manufacturers 

of thermal processing plants who have to contractually 

guarantee emissions limits. 

In a case described in [9], a UK-based manufacturer of 

glass fibres used natural gas received from different offtakes 

of the transmission network. The gas provided to 

the factory was highly dependent on the current load of 

the network, and as such, its quality was not predictable 

at any given time. In the glass fibre manufacturing process, 

product quality is critically dependent on premixed 

burners in the forehearth, as the system has to maintain a 

constant oxygen partial pressure in the furnace and tight 

temperature control. In this case, variations in natural gas 

quality caused imperfections in glass quality, leading to loss 

of production. Also, furnace controls had to be frequently 

adjusted manually. Sampling the gas composition using a 

gas-phase chromatographer suggested that the reduction 

of glass quality was linked to changes of the nitrogen and 

hydrogen sulfide (H 2 S) concentrations in the natural gas, 

although these properties were always within the UK’s 

legal limits. In the end, the plant operators had to invest 

in a Wobbe Index control system which monitored the 

gas supply and diluted the fuel gas with air, if necessary. 

Next to process engineering applications, power plants 

are one of the major consumers of natural gas in Europe 

(cf. Fig. 3). Natural gas is for the most part used to generate 

electricity by means of stationary gas turbines, although 

gas engines or micro gas turbines can also be found in 

great numbers, especially as smaller, decentralized units. 

Large power plant gas turbines have seen a dramatic 

evolution in the last decades. Demands for higher electrical 

power outputs and efficiencies in combination with 

increasingly strict environmental regulations have led 

to high-performance designs with high pressure ratios, 

advanced materials and sophisticated cooling strategies 

for the turbine blades. One of the most important driving 

forces for gas turbine development in the power plant 

sector, however, was the effort to reduce NO X emissions. 

A peculiarity of stationary power plant gas turbines in 

comparison to firing systems in thermal processing applications 

is that gas turbines almost always operate in their 

design points. While industrial burners are often modulated 

over a wide range of operating points, operators of 

a gas turbine try to keep conditions within the combustion 

chamber as constant as possible. Contrary to other 

industrial combustion applications, modern gas turbines 

therefore generally use lean premixed burners (cf. Fig. 5) 

where fuel and oxidizer are thoroughly mixed prior to entering 

the actual combustion chamber [12]. Air excess ratios 

in gas turbine combustors, compared to most industrial 

burners, are relatively high; values of 2 to 2.5 are common. 

The advantage of this combustion concept is that despite 

elevated temperature and pressure levels in the combustion 

chamber, high energy densities can be achieved in a 

very small space at very low NO X emissions. Compared to 

other industrial combustion systems, gas turbine combustion 

chambers are very small, despite achieving electrical 

power outputs of 300 MW and more. 

The disadvantage is, however, that this form of combustion 

– compared to non-premixed combustion prevalent in 

most industrial applications – is inherently not very stable. 

Combustion dynamics, i.e. acoustic pressure fluctuations 

within the combustor, can occur in any combustion device, 

but lean premixed systems are especially prone to them. 

Such combustion dynamics occur when the heat release 

due to combustion is linked to pressure oscillations. They 

can reach high amplitudes and induce vibrations in the 

hardware, causing increased wear and reduced lifetime, or 

in extreme cases, even catastrophic failure of the component. 

Humming, screeching or thermo-acoustic pulsations 


77

REPORTS 

Gas Quality 

Fig. 5: Principle of a lean premix burner for stationary gas turbines [12] 

are other common names for this phenomenon [9, 11]. As 

the mechanisms leading to thermo-acoustic oscillations in 

gas turbine combustors are not yet completely understood, 

it is difficult to accurately predict the effects of changing 

fuel gas compositions on the dynamics of the combustion 

systems. Measurements indicate, however, that two fuel 

gases with identical Wobbe Indices may very well cause 

different dynamic behaviour [33]. 

An issue to be avoided at all cost in a gas turbine is the 

so-called flash back. The position of the flame front within a 

premixed combustor is governed by the balance between 

the flame speed on the one hand and local flow velocities 

on the other. The flame speed is highly dependent on the 

chemical composition of the fuel gas. If the flame speed 

of the fuel/air mixture moves outside of the design window 

of the burner, a flash back can occur where the flame 

front suddenly moves upstream, damaging the burner. 

Hydrogen contents are of particular concern in this regard 

as the laminar flame speed of hydrogen is much higher 

than that of methane. Higher hydrocarbons can also lead 

to flash back problems. 

A third important aspect in the context of gas turbine 

combustion is auto-ignition. It occurs when fuel is injected 

into the pre-heated combustion air and local temperatures 

are high enough to initiate combustion without an exterior 

ignition source. Higher hydrocarbons have significantly 

lower auto-ignition temperatures than methane, so that 

two fuels with similar Wobbe Indices may very well show 

different auto-ignition behaviours [9]. Gas engines have 

similar problems: changing fuel qualities can lead to premature 

ignition, the so-called “knocking” [34]. 

Combustion dynamics, ignition and flash backs are 

complex phenomena which are dependent on a number 

of factors such as air excess ratios, flow parameters (velocities, 

turbulence, etc.), mixing quality and placement of the 

fuel injectors. However, the chemical composition of the 

fuel also plays an important role. Therefore, gas turbine 

manufacturers specify acceptable fuel gases in great detail 

to ensure that their systems meet performance and operability 

standards. Based on a specified reference gas for 

which the installed machine was tuned for optimum performance, 

they usually permit variations 

of ± 5 % from either the Wobbe Index [9] 

or the Modified Wobbe Index [35] (which 

takes fuel pre-heating into account) of 

the reference fuel. Some manufacturers 

even restrict these variations to ± 2 % [12]. 

The Wobbe Index alone is clearly insufficient 

to characterize the complexities of 

combustion in a gas turbine combustor. 

Therefore, manufacturers also specify limits 

with regards to higher hydrocarbon 

and hydrogen concentrations [11, 35, 36], 

among other things. In addition to combustion-related 

issues, higher hydrocarbons are strictly regulated in order 

to avoid condensation within the turbine at elevated pressures. 

Acceptable fuel gas qualities for gas turbines are 

usually negotiated and performance is only guaranteed 

for fuel gases within the specified ranges [9]. 

Since they know about the susceptibility of their products 

to changing fuel gas qualities, gas turbine manufacturers 

are especially sensitive to the discussions on natural 

gas quality variations or even the feed-in of large amounts 

of hydrogen into natural gas distribution grids as it is proposed 

in some power-to-gas scenarios [37]. 

Although gas turbine manufacturers tend not to publish 

operational problems related to fuel gas quality, there are 

reports where gas turbines reacted negatively to unforeseen 

changes in fuel composition. While every change of 

fuel gas quality outside of the design window may cause 

problems (for example a sudden flame extinction in the 

burner or loss of efficiency), shifts to gases with higher 

Wobbe Indices are of special concern as these situations 

are more likely to cause damage. 

Such catastrophic component failures are rare, but when 

they occur, the results are dramatic, as can be seen in Fig. 6. 

Both examples, taken from [11], occurred in the UK and 

were linked to a content of higher hydrocarbons in the fuel 

gas in excess of the manufacturer’s specifications. The gas 

qualities were, however, still within the natural gas quality 

regulations of the UK. The image on the left hand side 

shows the result of a sudden flash back. Instead of stabilizing 

in the combustor, the flame front suddenly moved 

upstream to the burner due to a sudden increase in the 

flame speed and damaged the swirler vanes. In the image 

on the right hand side, the effects of thermo-acoustic vibrations 

on the material of the combustor can be seen. 

Usually, changing fuel gas compositions are more likely 

to affect emissions and efficiency than actually damaging 

the hardware. In 2005, there was a case reported in California 

[9] where the failure of a hydrocarbon liquids removal 

plant led to an increase of the Wobbe Index within the local 

gas supply by about 4.4 %. A group of four combined cycle 

power plants, all of them advanced systems with low NO X 


Gas Quality 

REPORTS 

burners and most equipped with SCR plants, had to handle 

this rich gas for about three days. While they managed 

to comply with the strict Californian NO X limits despite 

increased NO X formation in the gas turbines, the consumption 

of ammonia for the SCR plant rose significantly during 

that period, causing increased operational cost. 

Fig. 7 demonstrates the impact of fuel gas composition 

on NO X emissions based on operational experiences in the 

UK. In this image, again taken from [11], the base load NO X 

emissions of four gas turbines are correlated to the Wobbe 

Indices of their respective fuel gases. 

While these four gas turbines are nominally identical, 

differences in local conditions (e.g. ambient temperatures, 

pressures or humidity) as well as unit-specific differences 

due to ageing, maintenance and tuning cause significant 

scattering in this plot. Nevertheless, the trend for units 

A, B and C is obvious: increasing Wobbe Indices lead to 

increasing NO X emissions. The trend for Unit D, on the 

other hand, is much less pronounced and was found to 

be statistically irrelevant. The diagram demonstrates the 

impact of changes in fuel quality on NOx emissions, but 

also shows that even similar devices will react differently 

due to a variety of factors. 

As gas turbine manufacturers have to contractually guarantee 

emission levels, they tune their products to optimum 

performance for the locally available fuel gas and specify 

a very narrow range of acceptable fuel gas qualities. If the 

quality of the fuel gas changes beyond this range, an intervention 

and subsequent re-tuning are required to ensure 

optimum performance. 

The examples show the dilemma that both manufacturers 

and operators of many industrial gas-fired applications 

are confronted with: increasing demands on 

combustion processes with regards to safety, efficiency, 

emissions and product quality require ever more complicated 

combustion systems. While a great number of 

technical solutions have been developed to meet these 

demands for many industrial combustion applications, 

the resulting devices are sometimes less robust with 

regards to even small changes in operating conditions. 

Changes in natural gas composition may well contribute 

to such small changes and are beyond the operator’s 

control anyway. He can only react to changing fuel qualities 

once they are detected. 

The situation is further complicated by the fact that 

even within one specific class of industrial applications, 

there is a great variety of combustion systems with regards 

to age, maintenance standards, tuning and a number of 

additional factors which may influence their behaviour 

when confronted with varying fuel compositions. 

Industrial plants have very long life cycles. Glass melting 

furnaces, for example, are usually operated for 10 

to 15 years [31], other furnaces may exist even longer. 

Fig. 6: Damaged gas turbine burners due to flashback (left hand side) 

and excessive combustion dynamics (right hand side) [11] 

Fig. 7: Comparison of the base load NO X emissions of four nominally 

identical gas turbines as functions of the fuel gas quality [11] 

To retrofit all these furnaces and combustion systems 

to be able to deal with gas quality fluctuations, even 

within today’s regulations, would cause enormous costs. 

In fact, it is a common experience that older plants may 

sometimes respond in a more robust manner to changing 

fuel qualities than younger, more technologically 

sophisticated plants. 

The suggestion to tune combustion devices to a fixed 

gas quality, for example pure methane, might work for small 

domestic appliances, but is quite simply not feasible on the 

much larger scales of industrial combustion devices. It would 

also require large design margins (especially with regards to 

NO X emissions and potential overheating [23]) for the operation 

with the locally available fuel gas. 

POSSIBLE SOLUTIONS 

The political and economical boundary conditions for natural 

gas markets both in Europe and worldwide are changing. 

The evolution towards more flexible and variable gas 


79

REPORTS 

Gas Quality 

qualities is inevitable, with consequences for both users 

and manufacturers of residential, commercial and industrial 

gas-fired applications and devices. The range of possible 

measures to detect and compensate for fluctuations in 

gas quality is as wide as the range of gas-fired applications 

itself. Nevertheless, there are some common denominators. 

Operators and designers of gas-fired devices have to 

be aware that changing gas qualities can and will have an 

impact on their processes and products. Many operators, 

especially in thermal process engineering, have gotten 

used to a hardly changing natural gas supply and tend to 

take it for granted. Gas suppliers on the other hand need 

to acknowledge that industrial end users may very well 

have quite specific requirements with regards to gas quality 

which cannot be expressed by the Wobbe Index alone. 

Markets with traditionally more inconstant gas qualities 

may serve as an example on how intensified cooperation 

and communication between gas suppliers and operators 

of sensitive combustion processes can mitigate the impact 

of changing fuel gas qualities on manufacturing processes. 

In France, where local Wobbe Index variations of 7 % and 

more have been common for decades [38], gas suppliers 

offer their customers daily detailed natural gas analyses as 

well as alerts if certain variation thresholds are exceeded. 

On demand, they lease and maintain sophisticated gas 

quality monitoring equipment such as gas-phase chromatographers 

to their customers and support the integration 

of these devices into process control systems [26]. 

Gas conditioning facilities which maintain a narrow 

range of Wobbe Indices by either adding higher hydrocarbons 

(“enriching”) or dilutants such as air or nitrogen (socalled 

“ballasting”) are another possible way to guarantee 

gas quality, but at substantial cost and loss of efficiency. 

Improved measuring and automated control techniques 

are generally considered to be crucial to minimize effects of 

changing gas qualities [39]. Frequent manual interventions 

into furnace operation to adapt to changing gas qualities 

cannot be an economically viable long-term solution. 

Automated systems whose interventions are based on 

detailed data of fuel gas quality and furnace conditions will 

probably be the most efficient way to handle fuel quality 

fluctuations on the operators’ side. 

However, there is no global solution: instead, the chosen 

measurement and control strategies have to be tailored to 

the specific application. In manufacturing processes of the 

glass industry, for example, the use of gas-phase chromatographers 

to detect changing fuel qualities is a common, 

albeit expensive, way to handle gas quality fluctuations 

[9, 30]. Operators of gas turbines, on the other hand, report 

that GCs are often unsuitable to control gas turbine combustion 

because of their low sampling rates [36]. Due to the 

inherent high-frequency instability of the lean premixed 

combustion usually found in modern gas turbines, these 

devices require measurement techniques which can provide 

continuous monitoring of the fuel quality. 

In some applications, it may be sufficient to maintain a 

given Wobbe Index, while others, for example processes 

in the chemical industry, may require more sophisticated 

control features because natural gas is not only used as a 

fuel but also a base material. Ammonia production would 

be one such example where the methane content is of 

great importance [26]. 

In the future, operating an industrial combustion device 

while maintaining high standards of efficiency, emissions 

control and product quality (where necessary) will become 

an even more challenging task than it already is today. 

Operators will need comprehensive information on all relevant 

operating conditions as well as data about crucial 

boundary conditions of their processes. Detailed measurements 

of input and output states as well as advanced 

control techniques, for example model predictive systems, 

will become important tools to maintain optimum performance. 

CONCLUSIONS AND OUTLOOK 

The European markets for natural gas will see significant 

changes in the near future. Traditional sources will cease 

production while new sources, such as Russia and the 

Middle East, will play a bigger role. LNG and gases from 

regenerative sources will be fed into the distribution grids 

to a greater extent than before, and increasing cross-border 

trading as well as the harmonisation of European gases 

quality standards mean that end users will have to accept 

greater variability of the natural gas supply. 

These changes offer a number of advantages to Europe, 

such as an increased flexibility and security of supply due 

to a greater number of available sources as well as reduced 

CO 2 emissions by integrating renewable energy sources, for 

example biogas or hydrogen generated with excess wind 

or solar power. Increased international trading of natural 

gas is expected to increase competition, potentially leading 

to reduced gas prices in general. 

For industrial end users, especially those who operate 

sensitive combustion processes for manufacturing or 

power generation purposes however, these changes may 

present a significant challenge. In this article, a few examples 

from both thermal processing and power generation 

applications were presented which highlight the sensitivity 

of some modern industrial combustion processes to nonconstant 

fuel qualities. Other aspects, for example gas-fired 

piston engines or the use of natural gas as a feedstock in 

the chemical industry could be added. 

Operating industrial combustion processes with optimum 

efficiency, low emissions and high product quality will 

require cooperation of gas suppliers and end users as well 

as technological upgrades, especially in the form of sensors 


Gas Quality 

REPORTS 

and control systems, for many devices. The Wobbe Index 

as a single characteristic property of natural gas quality is 

often insufficient to describe gas quality alone, since different 

applications react differently to the various aspects 

of changing chemical compositions of natural gas. 

Stronger variations in fuel gas quality have to be taken 

into account to a greater extent than before during the 

design of industrial combustion processes, while retrofit 

strategies with improved detection and control measures 

have to be developed and implemented for existing plants. 

Operators in general have to be more aware of the potential 

impact of changing gas compositions on their processes. 

From the side of the gas suppliers, better communication 

about real-time natural gas compositions within the 

distribution grid would be useful to help end users with 

sensitive processes maintain high standards of efficiency, 

product quality and emissions control. 

LITERATURE 

[1] “Mandate to CEN for Standardisation in the field of gas 

qualities” European Commission Directorate–General for 

Energy and Transport, M/400 EN, Brussels, Belgium, 2007 

[2] “Common Business Practice: Harmonisation of Natural Gas 

Quality”, European Association for the Streamlining of 

Energy Exchange - gas (EASEE-gas), 2005-001/02, Paris, 

France, 2009 

[3] Drasdo, P.; Karasz, M.; Pustisek, A.: “Dis-harmony in European 

Natural Gas Market(s) - Discussion of Standards and 

Definitions” Zeitschrift für Energiewirtschaft, no. 37, 2013, 

pp. 143–156 

[4] Williams, T.: “European Gas Interchangeability”, 24 th World 

Gas Conference (PGCD), Buenos Aires, Argentina, 2009 

[5] “Technische Regel - Arbeitsblatt DVGW G260 (A), ‘Gasbeschaffenheit’”, 

Bonn, Germany, 2013 

[6] Williams, T.; McKay, G.; Brown, M.: “Meeting the Challenges 

- Gas Interchangeability Matters”, UK, 2007 

[7] “GASQUAL Deliverable Approved by CEN/BT WG 197 ‘Gas 

Quality’,” CEN/AFNOR/WG 197 N 231, 2010 

[8] Cagnon, F.: “National situations regarding gas quality” 

MARCOGAZ, UTIL-GQ-02-19, 2002 

[9] Guidebook to Gas Interchangeability and Gas Quality. BP/ 

IGU, 2011 

[10] “EN 437 Test gases - Test pressures - Appliance categories” 

Comité Européen de Normalisation, European Norm EN 

437:2003, Brussels, Belgium, 2003 

[11] Abbott, D.: “The impact of variations in gas composition on 

gas turbine operation and performance”, Energy Delta 

Institute Quarterly, vol. 4, no. 1, 2012 

[12] Abbott, D.: “The Impact of Fuel Gas Composition on Gas 

Turbine Operation”, British-French Flame Days, Lille, 

France, 2009 

[13] Nitschke-Kowsky, P.; Schenk, J.; Schley, P.; Altfeld, K.: “Gasbeschaffenheiten 

in Deutschland”, gaswärme international, 

no. 6, 2012, pp. 55–60 

[14] Cagnon, F.; Schweitzer, J.: “Gas Quality Harmonisation: The 

European Situation - Part 2: Possible model for harmonisation 

in the EU”, 25 th World Gas Conference, Kuala Lumpur, 

Malaysia, 2012 

[15] “EUA Policy Position: Gas Security and Supply”, energy & 

utilities alliance EUA, Kenilworth, UK, 2012 

[16] “Study on Interoperability – Gas Quality Harmonisation – 

Cost Benefit Analysis”, GL Noble Denton and Pöyry Management 

Consulting, Preliminary Report for the European 

Commission, 2011 

[17] “EUROGAS Statistical Report 2012”, Eurogas, 2012 

[18] Schweitzer, J.; Cagnon, F.: “GASQUAL project: a step closer 

to gas quality harmonisation in Europe”, International Gas 

Union Research Conference, Seoul, South Korea, 2011 

[19] Schweitzer, J.; Cagnon, F.: “Gas Quality Harmonisation: The 

European Situation”, 25 th World Gas Conference, Kuala 

Lumpur, Malaysia, 2012 

[20] Williams, T.; McKay, G.; Brown, M.: “Assessment of the 

impact of gas quality on the performance of domestic 

appliances (A pilot study)”, Advantica, Loughborough, UK, 

R 7409, 2004 

[21] Singer, B.C.: “Natural Gas Variability in California: Environmental 

Impacts and Device Performance: Literature 

Review and Evaluation for Residential Appliances”, California 

Energy Commission, CEC-500-2006-110, 2007 

[22] Altfeld, K.; Schley, P.: “Development of natural gas qualities 

in Europe”, gwf International., no. 2, 2011 

[23] Graß, G.; Burger, N.; Lücke, A.: “Projekt GASQUAL – Pilot- 

Studie Deutschland: Grundsatzposition von BDH und 

figawa”, Gaswärme international, no. 2, 2013, pp. 33–42 

[24] Dörr, H.; Giese, A.; Werschy, M.: “New gases and application 

technology”, DVGW-EDGaR First Joint Conference, Arnhem, 

The Netherlands, 2013 

[25] Cordier, R.: “A service offer in combustion control of gasfired 

industrial thermal processes: applications in the glass 

industry (melting furnaces and feeders)”, GLASSMAN, 2009 

[26] Cordier, R.: “Impacts des variations de la qualité du gaz H 

dans les usages industriels”, Colloque d’AFG sur la qualité 

du gaz, Paris, France, 2012 

[27] Nakajima, H.; Kume, T.; Ohashi, T.: “Status Report: Impact of 

Gas Quality Variation on Gas Appliances in Japan”, 25 th 

World Gas Conference, Kuala Lumpur, Malaysia, 2012 

[28] “Main Effects of Gas Quality Variations on Applications”, 

MARCOGAZ, UTIL-GQ-05-04, 2008 

[29] Giese, A.: “Auswirkungen von Gasbeschaffenheitsschwankungen 

auf industrielle Prozesse”, 87. 

Glastechnische Tagung, Bremen, Germany, 2013 

[30] Giese, A.: “Gasbeschaffenheitsschwankungen – Mögliche 

Auswirkungen auf industrielle Anwendungen”, gaswärme 

international, no. 2, 2013, pp. 70–75 


81

REPORTS 

Gas Quality 

[31] Spielmann, S.: “Schwankungen im Erdgasnetz und die Auswirkungen 

auf industrielle Feuerungsanlagen”, VIK Mitteilungen, 

no. 3, 2012, pp. 17–19 

[32] Fleischmann, B.: “Ergebnis einer HVG-Umfrage zu Erfahrungen 

der Glasindustrie mit Gasbeschaffenheitsschwankungen 

im Erdgasnetz” Hüttentechnische Vereinigung der 

Deutschen Glasindustrie e.V., Offenbach, Communication 

No. 2155, Offenbach, Germany, 2011 

[33] Ferguson, D.; Straub, D.; Richards, G.; Robey, E.: “Impact of 

Fuel Variability on Dynamic Instabilities in Gas Turbine 

Combustion”, 5 th US Combustion Meeting, San Diego, USA, 

2007 

[34] Gersen, S.; Rotink, M.H.; van Dijk, G.H.J.; Levinsky, H.B.: “A 

new experimentally tested method to classify gaseous 

fuels for knock resistance based on the chemical and 

physical properties of the gas”, International Gas Union 

Research Conference, Seoul, South Korea, 2011 

[35] “Specification for Fuel Gases for Combustion in Heavy- 

Duty Gas Turbines”, GE Power Systems, Inc., GEI 41040G, 

2002 

[36] Bland, R.: “Changes in Natural Gas Composition and its 

Effect on Low Emission Combustors”, Electric Light & 

Power, vol. 87, no. 06, 2009, pp. 50–51 

[37] Abbott, D.J.; Maunand, J.; Deneve, M.; Bastiaans, R.: “The 

Impact of Natural Gas Quality on Gas Turbine Performance”, 

European Turbine Network ETN, Ratcliffe-on-Soar, 

UK, 2009 

[38] de Renty, M.: “Variations de la qualité gaz en France : passé, 

présent et futur...”, Colloque d’AFG sur la qualité du gaz, 

Paris, France, 2012 

[39] Slim, B.K.; Darmeveil, H.D.; Gersen, S.; Levinsky, H.B.: “The 

combustion behaviour of forced-draught industrial burners 

when fired within the EASEE-gas range of Wobbe 

Index,” J. Nat. Gas Sci. Eng., vol. 3, 2011, pp. 642–645 

AUTHORS 

Dr.-Ing. Jörg Leicher 

Gas- und Wärme-Institut Essen e.V. 

Essen, Germany 

Tel.: +49 (0) 201 / 3618-278 

leicher@gwi-essen.de 

Dr.-Ing. Anne Giese 

Gas- und Wärme-Institut Essen e.V. 

Essen, Germany 

Tel.: +49 (0) 201 / 3618-257 

a.giese@gwi-essen.de 

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INFO: 

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82 Tel. +49 69 756081-0 · Fax +49 69 756081-74 

heat processing 3-2013 

emo@vdw.de · www.emo-hannover.de


REPORTS 

Increase of the lifetime of 

inductors by using microfusion 

by Katrin Struben, Pedro Moratalla 

The microfusion inductors are used in induction processes and are manufactured by a revolutionary and innovative 

technique that is being patented. Formerly handmade processes can be replaced by this industrial and computerized 

technique, achieving extraordinary benefits: increase of up to 30 % of lifetime which means reduction of spare parts 

consumption, possibility to manufacture identical replacements so that constantly good heating results can be guaranteed 

and less time for calibration is required, complicated inductor designs are no longer a problem so that they can 

adapt the applications much better and better results are obtained. 

Since the use of induction heating for the treatment 

of pieces in a large scale, for example for automotive 

components, a heating inductor has been required. 

In order to process the highest quantity of pieces, the 

heating inductor should have a very long lifetime. From 

the beginning, it has been desired that the inductor had 

an infinite lifespan, since changing the inductor means 

spending time to exchange inductors and having to check 

that the heating profile is still the same. As handmade 

inductors will never be exactly the same, the check of the 

correct heating profile is necessary with every changeover. 

In the traditional manual manufacturing process, the 

induction coil is formed by hand from a base material by 

brazing it according to a design sketch. Due to this manual 

production where every inductor is built in a unique way, 

there will always be a difference between one inductor 

and another, even if they are built with the same sketch. 

In addition, the handcraft production leads to other 

problems such as weak brazing points, different exterior 

and interior dimensions, partial obstruction of the interior 

of the inductor etc. 

processes of replacing inductors for handlings wherein 

hundreds of thousands of pieces are manufactured are 

optimized. 

■■ 

Durability: 

- The long-life cycle of the microfusion inductors is a 

result of different improvements: 

- Highly conductive metal alloy is used to manufacture 

the inductor so that electrical losses are minimized. 

- Production without any brazed joints which would 

mean weak points (Fig. 2). 

ADVANTAGES OF THE MICROFUSION 

INDUCTORS 

The microfusion technique (Fig. 1) has several advantages 

compared with the conventional production method: 

■■ 

Repeatability: 

The use of a data storage system for storing physical 

and mechanical characteristics of the inductor allows 

the exact reproduction of new inductors. Therefore, the 

Fig. 1: Example of an inductor made by microfusion, 

made in one piece without any brazed joint 


83

REPORTS 


- Use of planes in three dimensions for lowering the points 

of higher current density (hot spots) by changing the 

geometric characteristics of the inductors in the planes. 

- The cooling of the coil is improved as the interior construction 

can be controlled so that the cooling flow is 

increased in comparison with copper made inductors and 

the wall thickness can be adapted to special requirements. 

- Flexibility in the design: The result is the maximum 

efficiency of the application. Thanks to the 3D design 

and the construction with a mould instead of using 

brazed joints, the inductor coil can be adapted to the 

part in a much better way than traditional inductors 

could (Fig. 3, 4 and 5). 

Operations with microfusion inductors demonstrate that 

their lifetime is up to 30 % higher than the lifetime of traditional 

inductors. 

Another advantage of this innovative technique is the 

fact that the inductors can be repaired just like handmade 

inductors. 

GENERAL BENEFITS 

From an economic point of view, the above advantages 

of durability and repeatability have direct positive impact 

to the profitability of the projects: 

■■ 

Increased production: 

The increase of the lifetime of the inductors leads to 

less production stops for induction changes; and even 

in case an inductor has to be changed the operation 

and calibration time is much shorter. 

Fig. 2: Comparison of two coils for crankshaft treatment, microfusion 

and traditional copper made inductor 

■■ 

Savings in maintenance: 

The increase of cycles for each coil minimizes the 

consumption of inductors and the shorter reference 

changes also minimize the labour time required for 

such changes. 

■■ 

Reduction of stocks: 

The increase of cycles of the inductors combined with 

the reduction in delivery times due to the database 

storage of all required information result in a reduction 

of spare parts store. 

Fig. 3: Design in three dimensions of a coil with an interior track for 

the cooling and an exterior track for the quenching liquid 

■■ 

Quality of the parts: 

Multiple inductors can be made from the same prequalified 

mould with high dimensional accuracy. The 

ability to ensure that heating profiles are maintained is 

an added value for the companies. 

The profitability of those inductors is maximum when the 

production is for high and repetitive volumes. 

Fig. 4: Final coil for hardening, unrealizable with the 

traditional handmade process 

BACKGROUND OF THE PROCESS 

AUTOMATION 

All the automation attempts in the manufacturing of 

inductors have been made by means of machine tools 

developed for precisely machining the pieces and working 

on hard materials such as carbon steel. 

The basically used system consisted of machining the 

exterior of the inductor from a large piece of copper by 

removing all the excess of copper. 

With this system, a large amount of copper chips are 

generated, many machine tools are broken, and the hol- 



REPORTS 

low interior of the inductor is not obtained. 

Therefore it is necessary to perform a subsequent 

machining and the aperture through 

which the tool had been introduced should 

be capped. The result is an unknown interior 

gap of the inductor and deformations of the 

coil increasing the possibilities of water leaks. 

This method can only be applied to a 

very specific type of inductor for induction 

heating. 

MANUFACTURING PROCESS OF 

A MICROFUSION INDUCTOR 

The manufacturing process consists of three 

main phases (Fig. 6): 

1. Phase of designing the coil: 

a) The first step consists in generating one 

or more two-dimensional planes, with the 

external physical characteristics of the heating 

inductor. This step takes into account 

which will be the part that will be in the 

vicinity of the piece to be treated. This initial 

design will be determined by simulations 

based on previous experiences. 

b) The second step consists in generating 

a plane in three dimensions, which meets 

the characteristics determined by the initial 

planes. This plane in three dimensions has 

both the face and the exterior of the inductor, 

and the inside thereof, through which 

the cooling water of inductor will flow. In this 

plane both the electrical connections of the 

inductor, and the connections for the cooling 

water, will be drawn. The plane in three dimensions 

must contain all the information on inductor model, 

adapted from this plane both cooling and electrical 

improvements will be made, such as the possible future 

modifications to be carried out in new versions of the 

inductor. 

The creation of this plane has to be done on a data 

storage medium that fulfills two conditions: possibility 

to storage all information concerning the inductor in 

order to realize copies and capability to communicate 

with a printer for printing wax layers. In this plane in 

three dimensions three different spaces must be defined: 

i. The first space is determined by the internal parts of 

the inductor (through which the cooling flows), 

ii. The second of the spaces is formed by the body of 

the inductor (the tube walls), 

iii. The third space is formed by the external part of the 

inductor (corresponding to the areas wherein no 

operation has to be done). 

Fig. 5: Interior section of the coil; microfusion permits 

cooling of the inductor near the part 

Fig. 6: Main production phases for microfusion inductors 

2. Phase of printing the three dimensional design 

of the coil: 

The third step consists of the deposition of thin layers 

of wax that are formed one above the other the threedimensional 

model defined in the second step. This has to 

be done with specific machines for the deposition of wax 

layers controlled by a computer program. The mechanical 

characteristics of the wax must be such as to allow a 

three-dimensional model completely rigid. 

3. Phase of microfusion for the final coil: 

The three dimensional model obtained in phase 2 is used 

to obtain the final ceramic mould. This mould is put into a 

microfusion oven with centrifugal motion and filled with 

the suitable alloy that enables a high conductivity and prevents 

the formation of pores. The alloy consists of a compound 

material 25 % more conductive than copper. In the 

next and last phase the ceramic mould will be destroyed to 

extract the inductor. To eliminate the mould of third space 


85

REPORTS 


mechanical methods, by breaking the ceramic coating, are 

used. To eliminate the mould inside the inductor pickling 

chemical agents that remove the coating are used. 

Once the inductor is obtained, the next step is to eliminate 

the remaining parts of the mould that were used to 

connect the different spaces and plug the gaps left in 

the mould for filling the different spaces. In this process, 

machine tools for a final finishing of the inductor are used. 

WHEN TO USE A TRADITIONAL OR A 

MICROFUSION INDUCTOR? 

The use of a microfusion inductor or a handmade inductor 

is indifferent. However, there are several applications 

and processes where the microfusion inductor is very 

profitable. For example for complex applications and high 

volume productions with large series of pieces. 

REFERENCES 

The patent for the microfusion inductors was presented 

in 2008 and since 2010 they are commercialized, mainly 

implanted in industry groups for automation with special 

applications. In general, there are two implantation models; 

one where both types of inductors are used in parallel and 

another where all inductors are replaced by microfusion 

inductors. 

The experience from microfusion inductors in production 

shows an increase of cycle-times of up to 30 %. 

CONCLUSION 

The microfusion inductors will change the way of inductor 

manufacturing offering new opportunities to the industry. 

The improvements are in favour of the induction applications 

as well as for the production and maintenance in the 

companies using induction installations. 

AUTHORS 

Katrin Struben 

GH Induction Deutschland – GH Group 

Hirschhorn, Germany 

Tel.: +49 (0) 6272 / 9216-10 

katrin.struben@gh-induction.de 

Pedro Moratalla 

GH Electrotermia – GH Group 

Valencia, Spain 

Tel.: +34 (0) 961 / 352-020 

pmoratalla@ghinduction.com 









xxx 

REPORTS 

The smallest details 

make the greatest projects 

Discover 

microfusion 

technology, 

work with our engineers 

to design the most suitable 

solution for your application. 

GH invites you to the 

EMO Hannover tradeshow. 

Hall 11 - Stand G32 

16 - 21 of September 

GH GROUP – Induction solutions 

GH Electrotermia S.A. 

Vereda Real s/n 

46184 San Antonio de Benagéber (Spain) 

Tel.: +34 961 352 020 

info@ghinduction.com 


www.ghinduction.com 

87

REPORTS xxx 

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REPORTS 

DIN EN ISO 50001 – 

Opportunities for the 

international forging industry 

by Dirk M. Schibisch, Loϊc de Vathaire 

The much cited “Energiewende” has ambitious goals: as well as reducing greenhouse gas emissions by 80 % compared 

to 1990, the aim is to provide more than 80 % of Germany’s electricity from renewable energy sources by 2050. One of 

the measures taken to finance the energy transition was the passing of the German Renewable Energy Act (EEG), which 

aims to spread the costs of distributing electricity generated from renewable sources to end users by means of the EEG 

reallocation charge. Manufacturing industries certified to DIN EN ISO 50001 with high energy consumption rates have 

the opportunity of reducing their electricity costs in order to maintain their international competitiveness. Measures to 

ensure sustainable growth in energy efficiency are crucial for the certification process and lowering energy consumption. 

The aim of this article is to highlight examples of this potential, which is of particular interest for energy-intensive 

businesses in the forging industry. 

With the 2012 amendment and related fact sheets 

from the Federal Office of Economics and Export 

Control (BAFA), the Renewable Energy Act allows 

for special equalization scheme measures for energy-intensive 

businesses. Manufacturing industries with an energy 

consumption level of more than 1 GWh/yr and annual 

electricity costs of at least 14 % of the gross value added 

can apply to have the amount of the EEG surcharge limited 

to 90 % of the electricity portion of the EEG surcharge or 

more. One condition is that certification to EN ISO 50001 

applies for cases where there is an energy consumption 

level of more than 10 GWh/yr [1]. 

DIN EN ISO 50001 describes management system standards 

with the aim of achieving a continual improvement in 

energy performance and focuses on the processes within 

the organization. The aim is to reduce greenhouse gas 

emissions and other environmental impacts as well as to 

lower energy costs. At a higher level, the application of this 

standard worldwide contributes towards more efficient 

utilization of available energy sources as well as improved 

competitiveness. [2, pp. 54ff]. 

Essentially, the crux of this standard is to bring about an 

improvement in energy efficiency, defined in DIN EN ISO 

50001 as the relationship between achieved performance 

and energy used, i.e., energy consumption. [2, p. 57]. 

DIN EN ISO 50001 provides a summarised description of 

energy management systems aimed at promoting energy 

efficiency as an awareness of social responsibility, reducing 

energy costs and achieving financial benefits by complying 

with statutory requirements. 

The standard deals with all forms of energy, including 

natural gas, water and compressed air. However, this article 

focuses exclusively on electrical energy, the primary form 

of energy used in induction technology. 

First, definitions are provided for relevant terms, followed 

by an illustration of the opportunities to bring about 

lasting improvements in energy efficiency and thus lower 

energy costs and reduced emissions by optimizing the 

design of induction plants. 

The apparent power or connected load indicates the 

electric power being fed in or to be fed in to an electrical 

consumer. The apparent power S is taken from RMS values 

of the electrical current intensity I and voltage U, and 

is made up of the actual applied active power P and an 

additional reactive power Q tot [3]. 

It is not just the active power that energy-intensive businesses, 

in particular – such as those in the forging industry – 


89

REPORTS 


Fig. 1: Correlation between active power (P), reactive power 

(Q), apparent power (S) and phase angle (φ) 

Fig. 2: Grid energy consumption; example: throughput: 

3,500 kg/h, network consumption: 358 kWh/t, 

workpiece temperature: 1,250 °C 

Magnetic 

alternating 

field 

Coil current 

Eddy current 

Fig. 3: Induction heating of forging blanks using a copper coil 

are interested in, but the reactive power which is generated 

when the current and voltage are not in phase with each 

other. Alternatively, the portion of active power is shown 

over the phase angle or its cosine (cos φ) and is also called 

the power factor. The following rule of thumb applies: a 

power factor cos φ of 0.9 roughly corresponds to the statement 

”reactive power = 50 % of the active power” (Fig. 1). 

Active power P is taken from the supply network, if the 

voltage and current have the same sign, and fed back into 

this same supply network as a function of the working 

point of the electrical consumer, either fully or in part, as 

reactive power Q when the signs are opposing. To counteract 

the reactive power-related additional losses in the 

network supply, larger wire sizes are required in the supply 

lines as well as larger generators and transformers. 

Large-scale industrial electrical consumers have to pay for 

the reactive energy they use as well as the active energy 

they use [4]. Therefore it is in the interest of those energyintensive 

businesses to limit the reactive power as far as 

possible, if not eliminate it completely. To limit this, reactive 

power compensation systems are used, however these, in 

turn, have a negative impact on the energy balance. 

A better option here is working point-independent optimisation 

of the consumer power factor cos φ to a constant value 

close to 1 (barely any reactive power), by choosing suitable 

circuit topologies and thereby achieving a lasting increase in 

energy efficiency, which is explained in greater detail below. 

IMPACT OF DIN ISO 50001 ON THE 

FORGING INDUSTRY 

The forging industry is one of Germany’s most energy-intensive 

sectors. It is for this reason that it is closely following the 

trends associated with the energy transition which is marked, 

among other things, by rapid price hikes, higher network 

charges, increasing levies and above all great uncertainty 

with regard to the general situation in future. 

Despite the competitive advantages modern forging businesses 

have in terms of quality, innovation and precision, 

the proportion of energy costs relative to the added value is 

becoming hugely significant. To ensure long-term survival in 

today’s world of rising energy costs, every plant owner would 

be well advised to control and optimise his energy costs. 

Although induction heating plants are particularly energyefficient 

compared to other technologies due to the way 

they operate, they continue to account for the majority of 

the energy costs incurred. Therefore plant owners want to 

ensure that their plants are making the best use of the energy 

fed in. In practical terms the following questions often arise: 

■■ 

What definition of energy efficiency applies to the specific 

production framework? 

■■ 

What influence does the production range have on 

energy consumption and what opportunities does an 

optimum production strategy offer? 


REPORTS 


Fig. 4: Induced volume power density P‘‘‘ as a function of the 

ratio 1/δ at a constant frequency and variation of the 

workpiece diameter [6] 

Fig. 5: Varied heating/through heating at constant frequency 

and material parameters as a function 

of the workpiece geometry [7] 

in Fig. 4, very rapid, homogeneous temperature distribution 

is achieved over the cross-section when the cylindrical 

workpiece diameter is around 3.5 times greater than 

the penetration depth. These conditions are the result of 

a trade-off between direct, consistent heating over the 

cross-section with a correspondingly low frequency and 

increasing energy efficiency at high frequency [6]. 

Impressive evidence of this elementary connection 

was demonstrated in trials performed decades ago. Here 

cylinders of different sizes were introduced into a coil. With 

the varying colouration it is easy to see that both excessively 

small and excessively large diameters do not produce 

optimum through heating. Interestingly, this effect by far 

overrides the influence of the position of the material being 

heated within the coil. That is to say, although the optimum 

diameter, Fig. 5 bottom left, is not centred in the middle 

of the coil, it nevertheless produces the best result in terms 

of through heating. 

Ideally, this would result in the induction coil being perfectly 

matched to each material diameter. However since 

this is neither a practical nor cost-effective option for most 

applications, the forging shop product spectrum needs to 

be analysed precisely and grouped into reasonably practicable 

diameter ranges. The design of the coil, therefore, 

always represents a compromise between perfect matching 

and a high degree of flexibility [8]. 

The copper material 

In addition to the operating frequency and coupling distance, 

i.e. the ratio of coil and workpiece diameter, another 

efficiency driver is the material quality of the coil. 

As can be clearly seen in the formula for the electrical 

efficiency, this also depends on the material properties 

of the inductor. The specific electrical resistance of the 

inductor ρ Cu made from copper varies depending on the 

quality of the ultra-pure electrolytic copper. 

Table 1 shows the key difference for the two copper 

grades used regularly in electrotechnical components. 

Essentially both grades differ in terms of the copper content 

and machinability, which is particularly important for the 

manufacturers of coils made from this material. 

Coils made from Cu-DHP and Cu-HCP do not differ 

from a purely external point of view. Overall, however, Cu- 

DHP can be more easily worked, both mechanically and 

with regard to welding and soldering. Therefore some coil 

manufacturers choose this material grade with a slightly 

less copper content. 

However if one compares the specific electrical resistance 

ρ Cu of both these copper grades, it can be seen that 

the Cu-HCP material with the higher copper content of 

> 99.95 % shows a lower value. Over the temperature trajectory 

too, which is of particular interest for copper coils when 

used as an induction tool, the specific electrical resistance 

ρ Cu of Cu-HCP is around 30 % below that of Cu-DHP at 

every temperature point. Hence fewer losses are incurred 

when using higher-grade material, such that the electrical 

resistance is correspondingly higher. For induction coil 

manufacturers, the use of the Cu-HCP material does mean 

higher material costs on the one hand, with more labourintensive 

working due to the inferior material properties 

on the other hand, however for users in the forging shop, 

the energy-efficient properties of the higher-grade Cu-HCP 



REPORTS 

Table 1: Comparison between Cu-DHP and Cu-HCP [7] 

Full description 

Cu-DHP 

Deoxidized 

High Residual Phosphorus 

Cu-HCP 

High 

Conductivity 

Phosphorus 

Material no. CW024A CW021A 

Proportion of copper > 99.9 % > 99.95 % 

Weldability and solderability Very good Good 

Machinability Very good Good 

Energy efficiency Good Very good 

represent an interesting option for saving energy due to 

the considerably lower specific resistance (Fig. 6). 

The converter technology 

In the example given in Fig. 2, the operating 

efficiency of the converter is the 

third biggest influencing factor – after 

the inductor and thermal efficiency – 

that is influenced substantially by the 

duration of the heating process and 

thus by the length of the heating zone. 

As shown in the example, the newly 

developed generation of converters 

with a converter efficiency level of 

0.97 % and with an L-LC oscillating circuit 

is already in use. To some extent 

conventional converter topologies 

have far lower efficiency levels. L-LC 

denotes the wiring at the output of 

the inverter. With an uncontrolled rectifier, 

intermediate circuit capacitor, 

IGBT inverter and output choke, this 

converter features a constant cos φ of 

> 0.95 within all partial load ranges. [9] 

The L-LC circuit features two points 

of resonance: one with parallel and one 

with series resonance. Depending on 

the desired circuit properties and application, 

both may be used. To control 

the inverter, special algorithms have 

to be used to find the desired point of 

resonance (parallel or serial) and clearly 

establish the working point. For this 

the L-LC circuit has the advantage that 

both the frequency and power can be 

controlled via the inverter. [10] 

Using the L-LC converter topology as 

a basis, SMS Elotherm has further developed 

the iZone intelligent zone control system with high 

efficiency levels and improved energy efficiency. 

Fig. 6: Specific resistance of DHP and HCP-copper as a function of the temperature [7] 

Fig. 7 [9]: Part throughput rates: Manufacturing operation (green bar = inductor energized, 

the first 5 coils remain de-energized); Bar diameter 300 mm, selected 

part throughput: 6 t/h; Nominal throughput: 9 t/h; Energy savings with iZone 

compared to a conventional solution: approx. 20 % 


93

REPORTS 


Table 2: Bar diameter / tonnage 

Bar diameter (mm) 

Tonnage/year 

25 620 

28 3.150 

32 850 

> 32 150 

Total 4.770 

Table 3: Bar diameter / grid consumption 


25 515 

28 430 

32 370 

36 361 

40 353 

Grid consumption 

(kWh/t) 

Table 4: Grid consumption according to different bar diameters 


Grid consumption with inductor for bars 

ø 28 mm (kWh/t) 

25 369 376 

28 361 367 

32 (not possible) 358 

Table 5: Two optimisation strategies for the production 

Grid consumption with inductor 

for bars ø 32 mm (kWh/t) 

Optimisation strategy 1: 

Production with 2 sets of inductors 

Required induction coil sets Set 1: 

Existing set for diameters > 32 mm 

Optimisation strategy 2: 

Production with 3 sets of inductors 

Set 1: 

Existing set for diameters > 32 mm 

Set 2: 

New induction coil for the 25 to 

32 mm range 

Set 2: 

New induction coils for 32 mm 

Set 3: 

New induction coils for the 

25 to 28 mm range 

Potential energy cost savings approx. 294 MWh/year approx. 318 MWh/year 

Average industry electricity price 

2012/kWh (incl. taxes) 

€ 0,14 € 0,14 

Potential energy cost savings 41.160 €/year 44.520 €/year 

Set-up costs Low High 

Throughput-related plant design 

In terms of compliance with the requirements of DIN EN 

ISO 50001, the possibility of flexible adjustment of the 

heating plant in line with the various part throughput 

levels offered with the innovative L-LC converter topology 

and the iZone technology should be highlighted here. 

Using the data input by the operator, the iZone control 

system makes a direct, online calculation of the best 

heating strategy with resource-efficient energy consumption. 

In the case of bars with a diameter of 300 mm and 

a part throughput rate of 6 t/h, energy savings of around 

20 % compared to conventional solutions can be achieved 

(Fig. 7) [9]. 

RESULT OF AN INDUCTION AUDIT 

Below is a specific example of how a sustainable reduction 

in grid consumption – and thus increased energy efficiency 

– can be achieved with the optimal design of an induction 

heating plant. 

In the example shown, a forge shop has an induction 

heating plant with a nominal power of 1,500 kW in use 

upstream of a horizontal multi-stage press. Bars within the 

25 to 40 mm diameter range are heated to 1,250 °C over a 

section comprising five induction coils. The existing inductors 

are used for the entire product range. 

The particular benefits of such flexible induction coils 

are immediately visible, as the inductors do not require 



REPORTS 

changing. The following data was gathered in the induction-related 

audit: The bar diameter in a ratio to the tonnage 

per year (Table 2) as well as the bar diameter in a 

ratio to the grid consumption (Table 3). 

This data clearly shows that the grid consumption 

increases substantially if the coil diameter and material 

diameter are no longer ideally coordinated. 

Given the annual tonnage, optimised heating of 

the type 28 bars, in particular, is desirable. The calculation 

of the induction coil designed for a 28 mm and 

32 mm diameter shows that the grid consumption is as in 

Table 4. This results in two optimisation strategies in 

which the energy cost savings and the set-up costs may 

vary: the production can be optimised with two or three 

sets of inductors (Table 5). In this example optimisation 

strategy 1 proves to be the optimal result of the 

induction-related audit. 

More than € 40,000 can be saved every year with 

just one additional set of induction coils. The additional 

investment in a further set of coils would increase the 

savings made by just around 10 %, therefore in terms 

of the additional set-up costs and the average investment 

costs it would not be cost-effective. Since bars 

in the > 32 mm diameter range make up just a small 

proportion of the annual output (~ 3 %), they should be 

produced wherever possible using intelligent production 

schemes, to keep changeovers to a different set of 

coils to a minimum. 

As far as the aims of DIN ISO 50001 are concerned, this 

result – in real terms – means savings of around 166 t CO 2 

per year. The conversion factor of 1 KWh electricity to 

0.566 kg CO 2 , published by the German Environment 

Agency for 2011, forms the basis for this figure. [11] 

CONCLUSION 

The subject of DIN ISO 50001 is, for a variety of reasons, 

gaining a lot of attention at the moment. As well as 

increasing awareness of energy efficiency as an aspect 

of social responsibility and complying with legal requirements, 

the aim in the industrial sector is to gain financial 

benefits to increase one’s own competitiveness 

by reducing energy costs and adhering to specific key 

figures. 

This article has dealt primarily with those aspects of 

economic interest relating to the reduction in energy 

consumption and the improvement in the overall efficiency 

and power factor of an induction heating plant. 

For these electroheat plants in particular, manufacturers 

have a variety of possibilities on offer for increasing part 

efficiency levels through intelligent plant design. 

In addition, the specific calculation given above 

shows that long-term energy cost savings can be made 

by optimising just one partial aspect, in this case the 

coordinated coil set, and that significant success can 

be achieved with regard to a reduction in emissions. All 

of which also takes into account the economic framework 

parameters to help ensure that competitiveness is 

improved by implementing such measures. 

In the short term, energy efficiency audits can be used 

to work out and implement practical solutions which 

directly improve the energy efficiency of individual 

induction heating plants upstream of forming equipment 

and thereby bring about an immediate reduction 

in energy consumption. 

Over the long term the costs of implementing a DIN 

ISO 50001 energy management system are worthwhile, 

given the continual increase in the energy efficiency of 

the company overall. 

LITERATURE 

[1] wikipedia/ Energiemanagement 

[2] Reese, K.: DIN EN ISO 50001 in der Praxis, Vulkan-Verlag 

GmbH, 2012, pp. 54ff. 

[3] wikipedia/Scheinleistung 

[4] wikipedia/Blindleistung 

[5] Fact sheet 236 „Wärmebehandlung von Stahl – 

Randschichthärten“, 2009 edition, Stahl-Informationszentrum 

Düsseldorf 

[6] Taschenbuch Industrielle Wärmetechnik, Vulkan Verlag 2007, 

pp. 356 ff. 

[7] Data sheets from the German Copper Institute 

[8] Jürgens, R.; Scholles, M.: Dynamisches Energiemanagement 

in modernen Induktionsanlagen zur Steigerung der Energieeffizienz, 

elektrowärme international 1/2010, Vulkan Verlag 

Essen 

[9] Gies, J.; Schibisch, D.: Einsatz neuester Induktionstechnik zur 

nachhaltigen Steigerung der Ressourceneffizienz in der Massivumformung, 

elektrowärme international 2/2011, Vulkan 

Verlag Essen 

[10] Zok, E.; Schibisch, D.: Energieeffiziente Leistungsversorgung 

induktiver Härte- und Erwärmungsprozesse, elektrowärme 

international 3/2012, Vulkan Verlag Essen 

[11] http://www.umweltbundesamt.de/energie/archiv/co2- 

strommix.pdf 


95

REPORTS 


AUTHORS 

Dipl.-Wirtsch.-Ing. Dirk M. Schibisch 

SMS Elotherm GmbH 

Remscheid, Germany 

Tel.: +49 (0) 2191 / 891-300 

d.schibisch@sms-elotherm.com 

Loϊc de Vathaire 

SMS Elotherm GmbH 

Remscheid, Germany 

Tel.: +49 (0) 2191 / 891 324 

l.vathaire@sms-elotherm.com 

IZONE - INTELLIGENT ZONE CONTROL OF FORGE HEATING PLANTS 

The overall concept of this heating system is based on 

the further development of the zone technology which 

has been in use since the early 1990s and known today as 

iZone. iZone was developed by SMS Elotherm for the 

process control of modern induction heating plants. Longterm 

optimisation of the process results can be achieved 

in conjunction with an integrated computer system. With 

the dynamic energy management system, single heating 

coils or groups of them can be controlled individually, 

resulting in much lower consumption rates and thereby 

fully meeting current requirements with regard to longterm 

energy savings. 

Benefits of this innovative technology: 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

■■ 

Implemented heating strategies 

Interactive process optimisation 

Setting of individual heating curves 

Control of individual inverters 

Intuitive user guidance 

Integrated expert system 

Holding mode with identical coils / reversing mode 

Fast run-in for start-up 

Calculation and setting of optimum heating section 

Scale minimization program 

Intelligent energy management 

Iterative job control 

Automatic de-activation of coils 

Optimised energy consumption 

Extensive data backup 

Formula and process data administration 

The database-supported expert system automatically 

calculates the parameters required for the heating process, 

always aiming at the highest level of energy efficiency and 

the greatest possible reduction in scale. The resulting process 

parameters are then transferred directly into the plant system. 

The graphics function integrated into iZone is another 

tool used to safeguard the process. 

Using the heating curves individually generated by 

the operator, the system automatically calculates the 

process parameters and transfers these directly into the 

machine control system. 

Production can then be started straight away at the push of 

a button. Standard optimisation variants are already integrated. 

Another advantage is the running of bars with residual 

heat. Up until now one had to wait until the bars had 

cooled down to room temperature. The heating system featuring 

iZone technology enables the bars which are still 

warm to be re-heated even before cooling down to room 

temperature. For this the bars are automatically transferred 

back to the induction heating system and the amount 

of energy required for through heating is calculated and 

applied. In terms of energy efficiency, this means that not 

only is the heat already introduced not wasted, but the 

plant adjusts flexibly to the quantity of heat remaining and 

only applies the energy required to ensure the optimum 

forming temperature. 

SMS Elotherm uses this pioneering control system in both 

billet and bar heating plants and in large-scale quench and 

temper lines, that is the heat treatment lines for long products. 



REPORTS 

Temperature measurement in 

induction heating applications 

by Albert Book 

Pyrometers are used to measure temperatures in induction heating processes. One can choose between single wavelength 

and dual wavelength techniques. This article explains how these two techniques differ with regard to function, 

optics, and operability, and how each will impact measurement data. Furthermore, the latest technological advances 

are described. 

Advanced induction heating systems are widely 

employed in today’s forging industry for hot-forging 

applications. Prior to forging, steel is heated to a 

temperature between 1,000 and 1,250 °C. The required 

process temperature depends on the carbon content and 

the specific alloying elements of the steel. Hot forging 

requires uniform heat distribution across the width and 

the length of the workpiece. The billet is heated to a temperature 

above its recrystallization temperature. There are 

various ways to heat metal in hot forming. These include 

induction, gas and oil fired furnaces, infrared radiation and 

electrical resistance heating. Induction heating offers distinct 

advantages: quick heat up, uniform heat distribution, 

and precise temperature control. 

SIGNIFICANCE OF TEMPERATURE 

MEASUREMENT 

Steel billets, by far, represent the majority of hot-formed 

billets, although other materials including titanium, aluminium, 

copper, brass, bronze, and nickel are also induction 

heated for hot forming. Steel alloy grades are not necessarily 

always of the same precise composition. For example, 

most plain carbon and low alloy steels can have a carbon 

content of about 0.05 %. Variations in the steel’s carbon 

content can result in deviations of 90 °C in the solidus temperature. 

Hence, the optimal forging temperature within a 

single grade can vary, depending on the precise chemical 

composition of the steel. 

Steelmaking operations have improved over the years 

and the steel that is obtained from a reputable supplier 

will often have a very consistent chemical composition. 

Nevertheless, the possibility of variations in the chemistry 

of a given steel demands precise temperature control. 

Successful forging operations require an awareness of 

the steel’s specific physical properties which permit precise 

adjustment of process control parameters. 

FACTORS WHICH INFLUENCE 

BILLET TEMPERATURE 

Both the amount of power applied to the billet as well 

as the production rate of the induction line will determine 

the temperature of the heated billet. The heating 

power controls the amount of current provided to the 

induction coil. The electrical energy is transformed into 

heating energy inside the billet by the help of the induction 

coil box. The speed at which the billets are pushed 

through the induction line will dictate the temperature 

of the billet as well. Other parameters which will influence 

temperature and process efficiency are the diameter 

of the induction coil box hole and the cooling rate 

of the heater coil. 

PYROMETER TEMPERATURE 

MEASUREMENT 

For temperature control, induction heating systems use 

pyrometers, also known as infrared thermometers. These 

instruments measure temperature without contact and 

have no wearing parts. Based on Planck’s radiation law, a 

pyrometer captures the infrared radiation and converts it 

to a temperature value. 

Within milliseconds, and from a safe distance, a 

pyrometer detects the temperature of the billet at the 

moment it exits the inductor. The temperature data 

serves as a process control variable or as criteria for 

rejecting billets whose temperatures were not within 

the permissible range (Fig. 1). 


97

REPORTS 


TWO DIFFERENT TECHNIQUES 

Pyrometers can be divided into single-colour and twocolour 

pyrometers. Single-colour instruments detect infrared 

radiation at one spectral waveband. The two-colour 

technique lets the pyrometer detect the radiated infrared 

energy simultaneously at two separate wavelengths. The 

pyrometer calculates the temperature based on the ratio 

of these two intensities (Fig. 2). 

Both kinds of pyrometers – single-colour and two-colour 

– are employed in induction heating processes. Selecting 

the right instrument will depend on a number of factors: 

required accuracy, desired device versatility, ease of operation 

and purchase price. 

Fig. 1: Billet rejection based on temperature 

Fig. 2: Two-colour pyrometers detect radiation at two wavelengths 

and produce a temperature reading based on 

the ratio of these intensities 

IMPACTS ON THE MEASUREMENT 

AND FACTORS TO CONSIDER 

Dust, smoke and steam 

When particles and partial obstructions in the line of sight 

weaken the signal at each of the two wavelengths to the 

same degree, the ratio of the two intensities remains constant. 

The measurement will not be impacted. A two-colour 

pyrometer continues to yield highly accurate and reliable 

temperature data even at signal attenuation of up to 90 %. 

Contaminated lens 

A protective quartz window attached to the pyrometer or 

the glass of a furnace porthole will not affect a two-colour 

measurement. In order to obtain accurate temperature 

readings using a single-colour pyrometer, the transmissivity 

of the specific glass must be considered by adjusting 

the emissivity or transmission setting. A dirty lens leads 

to signal attenuation and produces temperature readings 

which are inaccurately low. 

Signal attenuation 

Obstructions in the line of sight or dust and dirt on the lens 

will reduce the amount of infrared energy reaching the 

sensor. The latest two-colour pyrometers feature a signal 

intensity monitor, a function which triggers an alarm when 

a user-configured signal attenuation threshold is exceeded. 

This feature ensures the reliability of the measurement data. 

Routine lens inspections become unnecessary because 

the pyrometer itself indicates when the lens has become 

too dirty. This is not technically feasible for single-colour 

pyrometers. 

Small targets 

With single-colour pyrometers, the object to be measured 

must be larger than the pyrometer’s target spot. 

The single-wavelength technique produces a temperature 

reading based on the average of the entire infrared 

radiation captured within the spot. When the object 

does not completely fill the spot, the sensor will receive 

radiation emitted from background objects as well. If this 

background is cooler than the object, the temperature 

reading will be too low. 

This is not the case with two-colour pyrometers. If the 

targeted object does not fill the spot, the reduced signal 

will not influence the temperature reading. With the twocolour 

technique, a pyrometer will still produce accurate 

temperature readings when the object itself is up to 80 % 

smaller than the circular target spot. The percentage that 

needs to be filled depends on the material’s surface emissivity 

and it’s temperature. 

Ideally, the actual position of the object within the target 

spot should not make any difference. The pyrometers avail- 



REPORTS 

Fig. 3: Simple two-colour pyrometers will 

erroneously indicate an increase 

in temperature if the billet is in the 

peripheral area of the target spot 

Fig. 4: Rectangular measurement area enables easier alignment 

able on the market differ, however, in terms of quality. If the 

billet is captured closer to the peripheral rim rather than in 

the centre of the spot, this would affect the measurement. 

Instruments which feature simply designed optics, poor 

error correction capability and cheap sensors will exhibit 

temperature reading increases of 20 to 30 °C – even when 

the actual billet temperature remains constant (Fig. 3). 

Applications in which the billet’s diameter is hardly wider 

than the diameter of the pyrometer’s target spot will require 

especially precise alignment. 

A two-colour pyrometer is much easier to use in such 

situations. It is much less sensitive to the effect of partial 

illumination within the spot and thus the precision of the 

alignment is not nearly as crucial to the accuracy of the 

data. 

Pyrometers which feature a rectangular measurement 

area have recently emerged on the market. These instruments 

are even easier to focus onto the target object 

because they permit an even wider range within which 

the object may move (Fig. 4). 

Distance to the target and size of target object 

Another difference between the two pyrometer techniques 

is the degree to which changing target size and distance 

will influence the temperature reading. 

When measuring at a single waveband, the focus distance 

must be precisely maintained in order to yield accurate 

results. Induction heating systems often utilize singlecolour 

pyrometers with fix focus optics. When selecting 

the installation position, the exact focus distance must be 

observed. In actual practice, however, the required focus 

distance may not be feasible due to installation constraints 

or instruments with adjustable focus capability are sometimes 

adjusted incorrectly. 

The situation becomes worse when the induction line 

processes billets of varying sizes. When the billet diameter 

changes, the distance between sensor and target changes 

as well, and some of the billets will be out of focus. 

The degree to which incorrect focusing will lead to 

measurement error depends on both the size of the object 

and the quality of the pyrometer’s optical system. When 

the pyrometer’s measurement spot is only slightly larger 

than the target object, this can lead to substantial error, 

particularly with single-colour pyrometers. 

The chart in Fig. 5 shows how the pyrometer’s temperature 

reading changes according to the diameter 

of the billet. If, for example, the billet diameter doubles 

from 16 to 32 mm, a pyrometer with high quality optics 

will indicate a temperature increase of only 1 °C. In contrast, 

a pyrometer with simple, inexpensive optics will 

indicate a temperature increase of 6 °C. Assuming the 

billet’s actual temperature is 1,000 °C, and based on a 

diameter of 16 mm, the superior instrument will generate 

a measurement error of 1.2 °C whereas the temperature 

reading of the inferior instrument will deviate by 10 °C. 

When two-colour pyrometers are employed, errors and 

deviations resulting from factors such as a varying distance 

or size, or incorrect focusing will be negligible. 


99

REPORTS 


Fig. 5: The effect of target object size on the temperature reading 

Fig. 6: SSE curves of two pyrometers with different optics 



REPORTS 

Fig. 7: Latest innovation: pyrometer with builtin 

video camera and TBC feature 

Fig. 8: Measurement error of a single-wavelength pyrometer when emissivity 

changes by 10 % 

PYROMETER OPTICS 

The “size of source effect“ (SSE) specifies the optical factor 

which influences the accuracy of the temperature 

measurement. A pyrometer’s SSE indicates the quality of 

its optics by showing the target spot size with reference to 

the amount of energy the sensor receives from the radiant 

target. For a true comparison of the quality of pyrometer 

lens systems, one must compare the SSE curves. If 

manufacturers specify a target spot size with reference 

to 90 % of the total radiant energy received, a pyrometer 

featuring high-grade optics will achieve a spot diameter 

of Ø 10 mm whereas a low-grade lens system will have 

a larger spot size of Ø 14 mm (Fig. 6). With reference to 

95 % of total energy, the superior optics will achieve a spot 

size of Ø 11.5 mm whereas the spot obtained by inferior 

optics will increase considerably to Ø 23 mm. 

This illustrates why manufacturers of pyrometers 

which feature less sophisticated lens systems will, in 

their data sheets, specify the SSE based on a smaller 

percentage of relative energy in an attempt to suggest 

a smaller spot size. 

The position and size of the target spot is either indicated 

by a spot light or can be viewed by through-thelens 

sighting. The latest pyrometers on the market now 

feature an integrated video camera for sighting and monitoring 

(Fig. 7). 

A video camera makes it much easier to maintain 

correct alignment and focusing because the target can 

be viewed from the control room. The video camera’s 

TBC (target brightness control) dynamically adapts the 

light sensitivity to the target object captured within the 

measurement spot to produce a high-contrast image 

of the target. The temperature reading and the circled 

target spot are superimposed onto the image. A separate 

digital display unit is not needed to show temperature 

data. Sometimes a laser is used to indicate the target. 

The disadvantage of laser sighting is that the laser 

pinpoints the position of the target spot but not its 

exact size. 

Pyrometers with inexpensive or simply designed lens 

systems will correct for aberrations in the visible range 

but not in the infrared spectrum. In this case the target 

spot as indicated by the viewfinder will not correspond 

to the actual spot size and focusing distance of the measurement. 

The pyrometer operator runs the risk of an 

incorrectly focused target. 

The measurement uncertainty which stems from the 

quality of a pyrometer’s lens system is often underestimated. 

The potential for measurement error due to poor quality 

optics is much bigger than commonly assumed, however 

often disregarded when pyrometer comparisons are made. 

Instead, pyrometer purchase considerations often place 

undue emphasis on the manufacturer’s data specifications 

regarding metrological error. 

Two-colour pyrometers are generally much less susceptible 

to optical impairments to the measurement than 

instruments measuring at a single waveband. 

Surface characteristics 

The emissivity of a material’s surface is another significant 

aspect to consider in pyrometer measurement. The 

effect of emissivity on the temperature reading is quite 

different for single and dual waveband techniques. For 

single-colour pyrometers, the wrong emissivity setting 

will directly produce inaccurate data. In actual practice, 

emissivity varies according to material and surface 

characteristics. It is difficult to avoid error. The potential 

for error will depend on the sensor’s spectral response. 

The shorter the wavelength, the smaller the influence 

of emissivity on the measurement (Fig. 8). 


101

REPORTS 


In applications where the effect of emissivity must be 

kept as low as possible, narrow band pyrometers with a 

spectral response of ≤ 1 µm are usually the best choice. 

The limitation of these pyrometers lies in their measuring 

range which starts at approximately 500 to 600 °C; they 

cannot be used for low-temperature applications. 

Two-colour pyrometers have the advantage that emissivity 

fluctuations (when they are equal at both wavebands) 

will not have any effect whatsoever on the temperature 

indication. Thus, when two-colour instruments are used, 

the target’s specific material characteristics and surface 

properties can be disregarded. 

TEMPERATURE READING 

AND DATA COMMUNICATION 

Induction heating systems in Europe are commonly 

equipped with a temperature measuring device. The 

process control system ensures that process parameters 

are maintained. Billets that have not reached forging 

temperature or have been overheated automatically 

end up as rejects. 

In countries which employ less advanced technologies 

it is still common to find flame heating which does not permit 

precise temperature measurement. Induction heating is 

becoming more popular, however, and forging operations 

are increasingly switching to induction heating lines. In the 

process of retrofitting their equipment, forging companies 

often purchase a temperature measuring instrument as a 

stand-alone device. For such applications, it is beneficial to use 

an intelligent digital display unit to enhance the pyrometer’s 

rapid signal processing to automatically generate accurate 

billet temperature data. The display unit, by means of switch 

relays and valves, controls billet sorting based on the configured 

process temperature. This may or may not include 

separate sorting equipment, depending on how the production 

line is configured. More recently the market has seen 

the emergence of display units which can count and log the 

number of accepted and rejected billets. This recorded data 

can be exported to a connected PC or the user can choose a 

wireless data communications option via a smartphone with 

a Bluetooth interface. A forging company which employs a 

self-sustained (non-integrated) temperature measurement 

device will only detect billet irregularities after the accept/ 

reject data has been recorded and evaluated; only then the 

operator can intervene in the production process. 

CONCLUSION 

Precise temperature control is essential towards achieving 

the highest possible efficiency in induction heating 

of billets. 

Single-colour pyrometers yield good results when 

production parameters such as target size, focus distance, 

material and surface properties remain constant, 

and when the measured object is at least 3 to 5 times 

larger than the pyrometer’s spot size – provided that 

the pyrometer itself is equipped with a high-grade lens 

system which can minimize the potential for optical 

error. Selecting a short-wavelength pyrometer will also 

help reduce the extent to which the object’s surface 

properties might impact the measurement. 

If, however, maximum data accuracy and ease of focusing 

are desired, a two-colour pyrometer will be the instrument 

of choice. Especially applications which involve 

varying process conditions or line-of-sight impediments 

such as steam, dust or dirt will benefit greatly from the 

dual-waveband technique. In most situations, two-colour 

pyrometers is far superior to single-colour pyrometers. 

Budget considerations also play a role in purchase decisions; 

depending on its features, a two-colour pyrometer 

will cost 50 to 100 % more than a single-colour device. 

AUTHOR 

Dipl.-Ing. Albert Book 

Keller HCW GmbH – Division MSR 

Ibbenbüren, Germany 

Tel.: +49 (0) 5451 / 85 -320 

albert.book@keller-msr.de 

www.heatprocessing-online.com +++ www.heatprocessing-online.com +++ www.heatprocessing-online.com 


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6/4/13 4:41 PM

REPORTS 


Reducing energy consumption 

at partial-load operational range 

on the example of a continuous 

furnace 

by Ralph Behrend, Marc Hölling, Marco Schünemann, Volker Uhlig 

This article outlines the most common causes for reduced efficiency. Easily implementable measures for reducing energy 

consumption at a partial-load operational range have been tested and evaluated for a walking hearth furnace. Possible 

solutions are presented and a shutdown of burner rows is discussed in detail. 

Industrial furnaces are durable investment goods. Assuming 

regular maintenance, service and repair, industrial 

furnaces can easily remain in operation more than 30 

years. On the other hand, one must consider the fact that 

industrial enterprises are operating in an ever changing market 

environment. The utilization ratio varies depending on 

economic situation, product line-up, market demand and 

customer requirements with an increasingly high frequency. 

Therefore, corporations depend on production facilities 

which can be adapted for a wide range of applications. 

Examples of facilities with long operation times are reheating 

furnaces in the steel industry. The layout for plants of this 

type may have been done for parameters which are significantly 

different from current needs. Furthermore, one has to 

consider that design parameters were chosen according to 

the users specifications. The “furnace performance” is understood 

as the highest possible throughput. When choosing the 

engineering parameters, the designer typically assumes the 

highest possible throughput while still having some reserves. 

These reserves are needed to compensate for aging and 

wear, cover uncertainties in furnace design and for the adaption 

of changes in processing. Facilities are not always operated at 

the design point. Therefore, it can be assumed that a potential 

for increasing efficiency lies in these facilities. Based on analyses 

undertaken at ArcelorMittal Hamburg GmbH, this paper will 

show some easily implementable measures to reduce the 

specific energy consumption in a continuous furnace. 

STARTING POINT 

ArcelorMittal Hamburg GmbH produces a variety of wire rods 

in various qualities, ranging from mild steel to high tensile 

steel. Dimensions between 5.5 and 16 mm are rolled. The 

heating furnace was built in 1983 by DIDIER-OFU as a walking 

hearth furnace with top heating using overcritical flat flame 

burners. The furnace was originally designed for an hourly 

throughput of 150 t of steel beams. In reality, this capacity 

is used in less than half of the operating time, due to the 

fact that the production of wire rod, for example a diameter 

of 5.5 mm leads to a decreased throughput caused by the 

capacity of the rolling train. The task was to adapt the furnace 

with as little effort as possible in order to reduce the specific 

energy consumption per ton of steel without compromising 

the quality of the product. 

PLANT DESCRIPTION 

The examined furnace has the following dimensions: 

■■ 

■■ 

■■ 

■■ 

Usable length: 

Unobstructed length: 

Unobstructed width: 

Unobstructed height: 

27,130 mm 

28,800 mm 

14,800 mm 

1,600 mm 

The furnace is heated by 126 overcritical flat flame burners, 

distributed over five zones (Fig. 1). Zone I is equipped 

with burners each of which has an output of 420 kW. This 



REPORTS 

Table 3: Mean specific heat capacity of moist exhaust 

gases between 0 °C and T in kJ/(m³ K) [1] 

Exhaust gas 

temperature 

in °C 

GUS natural 

gas H 

"Verbundgas 

H" 

0 1,371 1,372 1,373 

200 1,410 1,411 1,412 

400 1,449 1,450 1,452 

600 1,488 1,489 1,491 

800 1,525 1,527 1,529 

1,000 1,562 1,564 1,566 

facilities or for facilities with accident-sensitive downstream 

equipment could be useful by means of preventive maintenance 

[4]. This requires an extensive online monitoring 

of the affected facilities and therefore results in high investment 

costs. 

During the experiments described herein with the walking 

hearth furnace, some burner rows in zone I (preheating 

zone) have been shut down with the goal of increasing 

the length of the convection zone and to increase the 

operation of the burners. The main aim was to decrease the 

energy consumption at the partial-load operational range. 

The applied measures will be described in detail, since a 

decrease in energy consumption without investment costs 

yields the best possible benefit cost ratio. 

North Sea 

natural gas 

H 

EXPERIMENTAL PROCEDURE 

The segmentation of the burners into the five 

zones is relatively coarse. The output control of 

the furnace is done zone-wise. Modern furnaces 

utilize a much finer segmentation down to the 

point where each burner or a small group of 

burners can be controlled separately. As a consequence, 

the shutdown of single burners had to 

be done manually. Furthermore, the control software 

had to be reconfigured to take into account 

the shut down burners in order to prevent an 

overload of the remaining burners. As a result 

of the manual shutdown, this procedure could 

only be performed for long phases of partialload 

operation. All rolling procedures for rods 

with a diameter of 5.5 mm were considered for 

such phases. 

In order to ensure the quality of the products, 

the experiments were carried out by shutting 

down only one row of burners. When it was confirmed 

that this had no influence on the product 

quality, a second row was shut down as well. This 

operating condition has been investigated thoroughly. 

Experiments with the shutdown of an additional 

third row were cancelled after it became clear that the 

control software was not able to hold the set temperature 

in the preheating zone. It can be assumed that the problem 

arises from the position of the point of measurement, which 

was not in the heated zone anymore when the third row 

was shut down. 

EVALUATION 

During the experiments, all important parameters have 

been monitored and recorded. The power requirement, 

the throughput of material, the downtime and the percentage 

of warm charging were recorded as the most 

important figures of operation. This data was compared 

with other rolling-cases for wire with a diameter of 

5.5 mm and without the shutdown of burner rows. Of 

special interest for the evaluation was the specific energy 

consumption per ton of steel beam. This is influenced 

by many factors, most importantly by the shutdown 

time and the warm charging. A regression model was 

derived in order to estimate the influence of the interference 

factors. For illustrative purposes, a regression over a 

single interference factor was carried out. For the overall 

evaluation, a multi component regression was applied. 

Fig. 2 shows the influence of burner shutdown on 

energy consumption as function of warm charging. Two 

aspects are clearly visible: On the one hand, the influence 

of the burner shutdown on the specific energy 

consumption is clearly visible; on the other hand, the 

strong effects of hot or warm charging on the energy 

consumption can be seen. 

Fig. 2: Regression of the specific energy requirement over the percentage 

of warm charging with the shutdown of burner rows 


107

REPORTS 


Fig. 3: Zone I in the flap position of 40 %; left: 5 burner rows operating; 

right: 3 burner rows operating 

Fig. 4: Burner utilization and exhaust gas temperature 

Fig. 5: Regression of the specific energy requirement over malfunction period with 

the shutdown of burner rows 

From the multi component regression, 

it can be calculated that the specific energy 

consumption for an operation of five 

burner rows in zone I lies at approximately 

1.264 GJ/t. Shutting down two burner rows 

decreases this value to 1.225 GJ/t. Savings 

of 0.039 GJ/t correspond to 3.1 % savings 

in fuel costs for partial-load operation. This 

seems to be a minor impact but it must 

be kept in mind that these savings can be 

accomplished without further investment. 

This concept can be extended, if a sufficient 

furnace control system allows for a more precise 

control of the furnace. This would enable 

the operator to use unplanned downtime to 

shutdown burners. 

As expected, the increased length of the 

convection zone leads to a reduced exhaust 

gas temperature – the latent heat in the 

exhaust gas could be used more efficiently 

for heating the goods. The savings by this 

measure have to be examined further, since 

a reduced exhaust gas temperature leads to 

a decrease in the preheating temperature 

within the recuperator. 

By shutting down burner rows, the 

utilization of the remaining active burners 

was increased. Overcritical flat flame 

burners need a certain volume flow rate of 

combustion gas and air in order to reach 

an overcritical state. Only by reaching 

this state do the flames become flat and 

spread over the nozzle brick. For the burners 

used in the analyzed case, volume flow 

rates in the range of 40 % of the nominal 

flow rates are necessary in order to reach 

the overcritical state. By shutting down 

burner rows, the remaining burners could 

be operated significantly longer with the 

required volume flow rates. 

Fig. 3 shows the differences in flame 

contours with the same flap position but 

with different numbers of operative burner 

rows. With a flap position of 40 % and three 

operating rows, zone I burns without a visible 

flame, while with five operative rows 

huge agglomerates of burning fluid are 

visible, indicating a diffusion flame with 

incomplete combustion. 

Fig. 4 shows the changes in burner 

utilization for zones I and II. The percentage 

of time during which the burners are 

working in their design range is shown. 



REPORTS 

The design range is the percentage of time in which 

the volume flow rates reach the critical point for flat 

flame generation. Clearly visible is the improvement in 

burner utilization in zone I. The improvements in zone II 

are not as significant but clearly visible. The exhaust gas 

temperature decreases while burner rows are shut down 

as well in accordance with theoretical considerations. 

The previously mentioned reduction in energy consumption 

by means of hot charging can be much higher, 

depending on the layout of the facility. For ArcelorMittal 

Hamburg, the layout prevents an effective hot charging 

since the facility layout leads to a strong cooling of the 

steel beams before they can be reheated. 

Energy savings by means of reducing unexpected downtime 

is an obvious insight, but oftentimes operators underestimate 

how short downtimes add up over the day and thus 

lead to massive hold-ups. Anticipatory maintenance could 

improve on this. Fig. 5 illustrates the influence of down times. 

Another important aspect for the evaluation of energy 

efficiency of thermo processing facilities has to be mentioned 

here. Usually, the efficiency of a plant is described 

through the degree of efficiency. For industrial furnaces, the 

combustion efficiency η C and the furnace efficiency η F are 

declared; the product of these equals the overall efficiency. 

The combustion efficiency is mainly affected by the outlet 

temperature of the exhaust gas. It is defined as follows: 

H 

−H 

η 

in out 

C 

= 

H 

in 

. 

H in 

sums up all delivered enthalpies, whereby the chemical 

enthalpy of the combustion gas is dominating. H out 

sums up the enthalpy of the exhaust gas and the energy 

losses through flare out. If the furnace is hot charged, the 

combustion efficiency remains nearly constant, assuming 

the recuperator is in the balance limits. If the balance is 

drawn for the exhaust gas only, the combustion efficiency 

decreases. The reason for that is the inevitable increase in 

exhaust gas temperature. Furthermore, the furnace efficiency, 

defined by 

Q̇ 

Ḣ 

η 

used good 

F 

= = 

Ḣ 

in 

−Ḣ 

out 

Ḣ in 

−Ḣ , 

out 

decreases. As a consequence it is more useful to evaluate a 

furnace under the aspects of specific energy consumption. 

CONCLUSION 

Especially older facilities yield potential for optimization 

that can be used without extensive structural refitting. The 

measures described in this paper were enough to cause 

savings in the combustion gas costs in the range of 3 %. 

This does not sound like much but could be achieved without 

any investment. Especially in economically uncertain 

times, this is an advantage that is not to be underestimated. 

For the case mentioned here, the idea emerged from an 

old operating manual. Therefore, it can be of great benefit 

to re-read old operating manuals, since existing measures 

for the increase in energy efficiency may have been dismantled 

or cancelled in times of cheap energy. These measures 

are still physically sound and work as well now as then. 

SYMBOLS AND ABBREVIATIONS 

Symbol Unit Name 

c J/(kg K) Specific heat capacity 

c p 

J/(m³K) Specific heat capacity at 

constant pressure at standard 

conditions 

H J Enthalpy 

H 

J/s 

Enthalpy flow rate 

H L 

J/m³ Lower heating value 

H U 

J/m³ Upper heating value 

l min 

m³/m³ Minimal amount of air 

needed 

m kg Mass 

m kg/s Mass flow rate 

P W Power 

q spec 

GJ/t Specific energy consumption 

q W/m² Heat flux density 

Q J Heat 

Q 

W 

Heat flow rate 

T °C Temperature 

ν exhaust 

m³/m³ Exhaust gas volume per m³ 

combustion gas 

V m³ Volume 

V 

m³/s 

Volume flow rate 

η -1 Degree of efficiency 


109

REPORTS 


SHORTED INDICES 

in 

Input 

C 

combustion 

CG 

Combustion gas 

F 

Furnace 

out 

Output 

spec 

Specific 

LITERATURE 

[1] Ruhrgas-Projektierungsprospektblatt: Erdgasdurchschnittswerte 

des Jahres 1990 

[2] Wünning, J. G.; Milani, A.: Handbuch der Brennertechnik für 

Industrieöfen. Essen: Vulkan Verlag, 2007 

[3] Pfeifer, Herbert und al., et. Energieeffizienz und Minderung 

des CO 2 -Ausstoßes durch Sauerstoffverbrennung. stahl und 

eisen. 2009, Bd. 129, 8, S. 51-62 

[4] Müller, A.; Plociennik, U.: EP 0 876 856 B1 Europa, 1998 

[5] Mobley, R. K.: An Introduction to Predictive Maintenance - 2. 

Edition. USA: Elsevier Science, 2002 

AUTHORS 

Dr. Marco Schünemann 

ArcelorMittal Hamburg GmbH 

Hamburg, Germany 

Tel.: +49 (0) 40 / 7408560 

marco.schuenemann@arcelormittal.com 

Dr. Marc Hölling 

ArcelorMittal Hamburg GmbH 

Hamburg, Germany 

Tel.: +49 (0) 40 / 7408469 

marc.hoelling@arcelormittal.com 

Dr. Volker Uhlig 

TU Bergakademie Freiberg 

Institute of Thermal Engineering 

Chair of Gas and Heat Technology 

Freiberg, Germany 

Tel.: +49 (0) 3731 / 392177 

volker.uhlig@iwtt.tu-freiberg.de 

Ralph Behrend 

TU Bergakademie Freiberg 

Institute of Thermal Engineering 

Chair of Gas and Heat Technology 

Freiberg, Germany 

Tel.: +49 (0) 3731 / 392177 

ralph.behrend@googlemail.com 

Handbook of Thermoprocessing Technologies 

Volume 1: 

Fundamentals | Processes | Calculations 

This Handbook provides a detailed overview of the entire thermoprocessing 

sector, structured on practical criteria, and will be of particular assistance to 

manufacturers and users of thermoprocessing equipment. 

Order now: 

Tel.: +49 201 82002-14 

Fax: +49 201 82002-34 


In Europe thermoprocessing is the third largest energy consumption sector 

with a very diversified and complex structure. Accordingly we find the application 

know-how for the design and the execution of respective equipment 

represented by a multitude of small but very specialized companies and their 

experts. So this second edition is based on the contribution of many highly 

experienced engineers working in this field. The book’s main intention is the 

presentation of practical thermal processing for the improvement of materials 

and parts in industrial application. Additionally it offers a summary of 

respective thermal and material science fundamentals. Further it covers the 

basic fuel-related and electrical engineering knowledge and design aspects, 

components and safety requirements for the necessary heating installations. 

Editors: F. Beneke | B. Nacke | H. Pfeifer 

2 nd edition 2012, 674 pages with additional media files and e-book on DVD, hardcover 

ISBN: 978-3-8027-2966-9 

€ 200,00 


FUTURE

Edition 4 PROFILE + 

This is where we focus in regular intervals on the main institutions and organisations active in the field of thermoprocessing 

technology. This issue spotlights the Foundation Institute of Materials Science in Bremen (IWT). 

Institute of Materials Science – IWT Bremen 

The Foundation Institute of Materials Science 

(Institut für Werkstofftechnik IWT) 

in Bremen is a leading institute for applied 

research and development in the field of 

metal working and metal processing. The 

IWT is a foundation under private law, founded 

by the AWT (Association for Heat Treatment 

and Materials Science) and the federal 

state Bremen. Majority of its funding the 

IWT gets from contract research and direct 

orders from industry and by national and 

international research projects funded e.g. 

by the DFG, AiF/BMWi, BMBF, EU commission 

and others. With more than 170 employees 

the IWT develops technologies that will be 

used in future metalworking and in industry. 

With a broad range of technical equipment 

at service, the main purpose of the IWT is to 

solve particular metalworking issues and to 

combine the results with basic research as 

well as applied industry research. 

The IWT emerged from the former Institute 

of Hardening Technologies in Bremen 

and is an institution with a long research 

tradition of more than 60 years. Unique in 

Germany, the IWT unites three major scientific 

disciplines: 

■■ 

■■ 

■■ 

Materials Science (Prof. Dr.-Ing. Hans- 

Werner Zoch), 

Process Technology (Prof. Dr.-Ing. habil. 

Lutz Mädler) and 

Manufacturing Technologies (Prof. Dr.- 

Ing. habil. Dr.-Ing. E.h. Ekkard Brinksmeier). 

The IWT-directors and department heads 

are also professors in the Production Engineering 

Department of the University of 

Bremen, which combines research and 

teaching and enables also future engineers 

to benefit from new materials research 

results. The Bremen Institute for Materials 

Testing (MPA) is affiliated with the IWT 

and sets additional focuses in the field of 

materials in building and construction. The 

interdisciplinary cooperation ensures innovative 

high level results in a short period 

of time. Located in the science park of the 

University of Bremen, the IWT’s know-how 

is supplemented through close networking 

with other research institutions and other 

faculties. Characteristic for this are the DFG’s 

(Deutsche Forschungsgemeinschaft) several 

Collaborative Research Centres, which the 

IWT is or has been in charge of. The Technology 

Broker Bremen (TBB), which was founded 

with some additional research institutes 

in Bremen, secures the efficient transfer of 

all research results. 

Below you will find some examples of 

the joint research focal points of the IWT. 

These were processed by the three main 

departments, each with their own specialized 

focus: 

■■ 

■■ 

the AiF-Leittechnologie initiative project 

EcoForge for High-Performance Components, 

the Research on Metalworking Fluids 

in projects BRAGECRIM-EPM and ERC- 

CoolArt as well as 

■■ 

the Collaborative Research Centre SFB – 

Distortion Engineering. 

A complete overview with an extensive 

bibliography as well as contacts for each 

subject can be found under this link: 

www.iwt-bremen.de. 

RESOURCE-EFFICIENT 

PROCESS CHAINS FOR HIGH- 

PERFORMANCE COMPONENTS 

– ECOFORGE 

The research project “EcoForge – Resource 

efficient Process-Chains for High Performance 

Components” of the leading 

research organization AWT has been funded 

by the German Federation of Industrial 

Research Associations “Otto von Guericke” 

e.V. (AiF) since November 2010 with the 

idea of developing “leading technologies 

for small and medium-sized enterprises” 

within the program to promote industrial 

research and development (IGF) funded 

by the Federal Ministry of Economics and 

Technology (BMWi). In addition to the three 

departments of the IWT, some other university 

research institutes are involved in 

the research cooperation: the Department 

of Ferrous Metallurgy (IEHK) at the RWTH 

Aachen University, the Institute of Metal 

Forming and Metal Machines (IFUM), and 

the Institute for Materials Science (IW) at 

the Leibniz University of Hannover, and 

the Institute for Metal Forming Technology 

(IFU) at the University of Stuttgart. 

The further development of a forging 

process chain from the forming process up 

to the final heat-treated component is the 

focus of the EcoForge project. The main 

purpose is to produce components with 

excellent mechanical properties with the 

help of resource-efficient process chains. 

An expedient inspection of the processes 

during the project is carried out via 

two variations of the process control: on 

the one hand with precipitation-hardened 

ferritic-perlitic steel (AFP) and „high ductility 

bainite“ steel (HDB) and on the other hand 

with case-hardened steel. 

The new process chain aims at obtaining 

intended performance characteristics of 

the component directly based on the forging 

heat with a possible expansion of the 

previous application limits of the material. 

To increase these application limits beyond 

the potential of currently used AFP-steel, 

a so called HDB-steel is investigated, prior 


111

PROFILE + Edition 4 

Fig. 1: Temperature history of a work piece in forging process (conventional 

vs. EcoForge manufacturing process) 

Fig. 2: Spray configuration and simulated workpiece temperature 

for bainitic hardening 

to its market launch. Based on the forging 

heat, components made from the HDB-steel 

should exhibit a full bainitic microstructure. 

It is also additionally investigated to what 

extent low-sulfur AFP-steel can be better 

processed through hot machining by utilizing 

already existing energy/process heat. 

Next to the adjustment of the final 

microstructure, processing microstructures 

can be adjusted by the controlled 

quenching of the forging heat which for 

example are to be case-hardened later 

(gear wheels, shafts, bearing rings). The 

use of case-hardened steel with bainitic 

microstructure aims at reducing the distortion 

caused during the case hardening. A 

bainitic microstructure also allows to significantly 

reduce the effort of hard machining 

as well as to save other resources (for 

instance in addition to the savings of the 

annealing) by reducing the process steps. 

The controlled quenching from the forging 

heat aims at obtaining a defined structure 

with a good machinability, which is needed 

in particular for surface-machining or deephole 

drilling. The three departments of the 

IWT are collaborating to optimize this step 

of the process-chain. The Materials Science 

department validates the microstructure 

for high machinability used by the Manufacturing 

Technologies department and 

collaborates with the Process Technology 

department on the development of a spray 

field ensuring a controlled quenching of 

the component from the forging heat. 

Main targets of the EcoForge project 

are the reduction of the time and 

energy used for the heat treatment and 

the reduction of the deformation forces 

through the use of the process heat. The 

use of the process heat for heat treatment 

significantly increases the energy efficiency 

in the manufacturing process as uncontrolled 

quenching and frequent re-heating 

of the components are avoided (Fig. 1). 

The integration of the heat treatment in 

the process chain of high-performance 

forged components aims at quenching 

the component in a flexible air-water 

spray nozzles array. The spray field providing 

the controlled quenching of the 

components is designed using the relevant 

heat treatment process parameters 

corresponding to the material properties 

for the chosen applications (Fig. 2). The 

spray field is combined with the recently 

awarded microstructure-sensor from 

the IW University of Hannover in cooperation 

with IWT. Afterwards a forging 

at elevated temperatures significantly 

reduces the forces acting on the forming 

while simultaneously guaranteeing a 

strain hardening in the component, thus 

positively influencing the characteristics 

of the component. The low machinability 

of bainitic microstructures is compensated 

through hot machining (machining 

at elevated temperatures) directly from the 

forging heat in the process chains. 

METALWORKING FLUIDS IN 

MACHINING PROCESSES – 

COOLART / BRAGECRIM 

Metalworking fluids (MWF) are used in 

the metalworking industry in a multitude 

of manufacturing and productions 

processes. MWF are often formulated as 

emulsions, in which different additives 

are added to the system to increase the 

process performing. The MWF function is 

to reduce the friction between the workpiece 

and the tool (lubrication), to dissipate 

the friction generated heat (cooling) 

and remove the generated chips. 

Due to mechanical, thermal, chemical, 

and biological stress in the process, the 

physical and chemical properties of the 

MWF change, which may negatively affect 

the quality of the produced workpiece, 

the tool life time, and the environment. 

According to the current state of technology, 

the quality of the MWF emulsion is 

detected by the non-process integrated 

analyses. These methods are often of limited 

significance and require a lot of time 

(off-line measurement). 

The IWT is trying to develop a direct 

MWF-quality monitoring and application 

in different areas with different approaches. 


Edition 4 PROFILE + 

In the line of a cooperative project between 

the IWT Process Engineering and the University 

of São Paulo as part of the “Brazilian- 

German Collaborative Research Initiative on 

Manufacturing Technology - BRAGECRIM” 

funded by DFG and CAPES an in-situ monitoring 

and control of the quality and stability 

of MWF emulsions is developed, which 

should take place online during the process. 

Therefore, the turbidity spectrum is continuously 

detected by an optical spectrometer in 

the process in order to draw conclusions on 

the physical stability of the emulsion coolant 

as well as to derive necessary interventions 

to stabilize the coolant system (Fig. 3). 

The Department of the IWT also develops 

technologies for MWF monitoring and basic 

research is achieved. This commitment is 

supported by the German Research Foundation 

(DFG) as well as the in an Advanced 

Investigators Grant of the European Research 

Council (ERC) named CoolArt. Within a project 

supported by the Federal Ministry of 

Economics and Technology (BMWi), a system 

for a constant, automatic optimization 

of the essential MWF supply parameters is 

developed by using the IR-TherMo-Grind 

grinding wheel established at IWT, which 

directly measures the temperature in the 

grinding gap. On the basis of the temperature 

measurement the system should 

regulate the nozzle position and the MWF 

pressure and volumetric flow. 

The microbial contamination of watermixed 

cooling lubricants is investigated and 

monitored by the manufacturing technologies 

of IWT with the help of the Department 

of Microbiology of the MPA (Fig. 4). 

Sediments of metal particles and chips 

represent a complex three-dimensional 

structure, which show a high surface-tovolume-ratio 

similar to a sponge and can 

therefore be colonized by a large number 

of micro-organisms. In low-flow areas, biofilms 

are quickly developed, which offer a 

special habitat for micro-organisms. It can 

be assumed that due to the high population 

density it is exactly in this deposition the 

essential processes resulting in the damage 

of the MWF occur. Throughout the analysis, 

basics for the settlement structure, the 

microbial diversity and physiological abilities 

are established. These findings will help to 

reduce or even prevent the disturbances 

during the production process, as well as 

clearly extend the service of the MWF in the 

machine tools. 

In addition to the basic research, the 

IWT also develops methods for the monitoring 

and cleaning of MWF in the industry. 

The aim is thus to integrate gas-sensor 

measuring systems as monitoring sensors 

in machine tools. Through a qualified training, 

they are capable of directly indicating 

the state of use of MWF in real time by 

detecting gases which are produced as 

end products by the metabolic processes 

of microorganisms. 

Moreover the researchers of the IWT are 

trying to solve the problem of the shavings 

and hard grains which remain in the MWF 

as remnants of the grinding tool by cleaning 

the MWF. In industrial practice very fine 

filters with a small volume throughput are 

often used regarding to the high demands 

on the surface quality of the component. 

Due to a frequently necessary filter change, 

the maintenance cost of the filter systems 

consequently increases. The objective of the 

project is to test the influence of the MWF´s 

particle contamination on the processed 

work piece and to develop guidelines for 

the economical design of bandpass filter 

system in industry. 

CONTROL OF DISTORTION 

IN COMPONENT MANUFAC- 

TURING – DISTORTION 

ENGINEERING 

Central problems in the production of components 

are the dimensional and shape 

changes which are characteristics of the socalled 

“distortion”. They are often associated 

with the heat treatment as one of the last 

steps of the component manufacturing. In 

many cases the heat treatment triggers and 

releases internal stresses, which are caused 

by the previous production steps. Reasons 

for the workpiece distortion may be the 

material homogeneity that already occurs 

in the steel production or during the transformation. 

Due to the extraordinary complexity 

of such operations there is a need 

of a long-term strategy which combines the 

individual aspects of overlapping process 

chains with a general overview. The IWT is 

examining this topic in a close cooperation 

between the main departments and partner 

institutions in other disciplines - which was 

funded from 2001 by the DFG within the SFB 

570 “Distortion Engineering“ in cooperation 

with the University of Bremen. 

The reasons for the distortion occurring 

during the heat treatment of steel components 

are systematically investigated by the 

IWT. Therefore components, such as e.g. 

bearing rings, shafts and gears, are examined 

in their production chains. Distortion 

Engineering encompasses the engineer-like 

control of the causes of distortion, on the 

one hand through the construction and 

manufacturing of components suitable for 

distortion and on the other hand through 

the specific exploitation of existing distortion 

potentials for the compensation of 

component distortions. 

The SFB 570 led to a paradigmatic 

change, whereas before distortion was 

mostly seen as a problem of the heat treatment 

with occasional isolated adaption 

in single machining steps. In contrast, the 

IWT is committed to an optimization of the 

whole manufacturing process. Thus only 

the consideration of the distortion as an 

attribute of the whole manufacturing chain 

is productive. Therefore the interaction 

between the influencing factors of every 

single manufacturing step on the distortion 

of the work piece have to be identified, 

Fig. 3: Insitu turbidity measurements of 

Metal Working Fluid MWF 


113

PROFILE + Edition 4 

Fig. 4: Microbiological investigation of MWF 

Fig. 5: Left: shaft in symmetric spray field for gas atomizer 

(experiment); middle: shaft in asymmetric spray nozzle 

field (simulation); right: distorted shaft after asymmetric 

cooling (simulation) 

understood in regard to their impact and included into a 

cross-system approach through a cooperation of all relevant 

technical disciplines. 

The IWT applies experimental design practices for the 

identification of the main influences and their interaction. 

Extensive process simulation complements the experiments, 

because of the multitude of influencing parameters. In order 

to detect the distortion causes it is necessary to register 

and document the relevant influencing factors. The distortion 

control includes alternative processes, as well as special 

equipment and adapted measurement techniques for the 

continuous process control and targeted intervention of 

the relevant influencing factors. For the realization of the 

optimized manufacturing chain communication between 

all involved technical disciplines is crucial. 

A fast and non-intrusive method based on X-ray diffraction 

was developed for the determination of material parameters 

of the work piece surface during the phase change 

and tension development during the heat treatment. The 

obtained data serves to understand processes, to identify 

distortion potential and to support the simulation and modelling 

in order to predict the distortion characteristics during 

the heat treatment. 

An exemplary possibility for the distortion minimization 

at the end of the process chain is offered by the application 

of “asymmetric quenching” for the specific compensation 

of the distortion. By knowing the distortion potential of 

a work piece it is possible to apply selective asymmetric 

quenching by the means of an adapted flow field with 

flexible nozzle positions in gaseous and liquid settings. 

Thus, it is possible to trigger targeted large distortions 

on cylindrical shafts compensating the typical curve of 

narrow workpieces (Fig. 4). The heat transfer at the workpiece 

could be influenced significantly by controlled jet 

quenching in liquid media or by spray cooling due to the 

influence of the boiling film and rewetting front compared 

to gaseous cooling. The asymmetric quenching of circular 

workpieces could be achieved by a selective control of 

the different nozzles (Fig. 5 and 6). All three main departments 

of the IWT, Materials Science, Process Engineering 

and Manufacturing Technologies, work within this crosssystem 

cooperation on current topics and developments 

in industrial production in order to accompany the change 

and the progress in metal processing all the way from 

interdisciplinary fundamental research to its application. 

Fig. 6: Ring in gas or spray nozzle field (experiment), right: ring in 

nozzle field (simulation) 

Contact: 

Stiftung Institut für Werkstofftechnik (IWT) 

University of Bremen 

Badgasteiner Str. 3 

28359 Bremen, Germany 

www.iwt-bremen.de 


Edition 7 

FOCUS ON 

“Practical experience is very 

important from the beginning” 

Dipl.-Ing. Horst Linn sen. is founder and president of the Linn High Therm GmbH group. 

In this interview with heat processing* he talks about the future of the energy industry 

and technological challenges, revealing his own personal energy-saving achievement. 

The energy mix of the future: Are you prepared to risk 

a prediction? 

Linn: My personal opinion is – based on past predictions 

– renewable raw materials, sun (more thermal than photovoltaics), 

wind, geothermal energy, nuclear energy possibly 

will merge in the middle of the century. However, energy 

saving is most important of course. 

Germany in 2020: How will people’s everyday life has 

changed as a result of changes in the energy industry? 

What fuel will they use in their cars? How will they heat 

their homes? How will they generate light? Risk a scenario! 

Linn: Cars have to be smaller and considerably lighter: 

50 % electricity and 50 % fuel. Houses have to be insulated 

much better (vacuum insulation panels in mass production 

are affordable), light-LEDs can be recycled better and are 

not as toxic as energy saving lamps and household appliances 

save at least 50 % due to customer generation. 

Sun, wind, water, geothermal etc.: Which renewable energy 

source do you consider to have the greatest future? 

Linn: Sun + wind + geothermal 

Which of the technologies currently emerging would 

you invest in today on that basis? 

Linn: Insulation technology and small wind power plants 

from 1 to 5 kW, mini CHPs, superconductivity and battery 

manufacturers, carbon fibre/basalt fibre, UV-LEDs. 

How do you assess the future ranking of fossil fuels 

such as oil, coal and gas? 

Linn: From 2025 on, it will be difficult and expensive. And 

we will continue having problems with CO 2 . 

And nuclear energy? How will, for example, Germany 

declare its position to this topic in future? 

Linn: Unfortunately bad – I prefer German nuclear power 

plants compared to the ones of many other countries. They 

are safer. However, we should think more intensely about 

final repository and quantity reduction of nuclear waste! 

Above all, however, Germany, as the country of mechanical 

engineers, should not miss to keep-up with technology 

and know-how and qualify young people. Decommissioning 

as well as final repository need specialists. It is a 

huge challenge, politically and economically seen, which 

is highly underestimated – more acceptance from all of us 

in Europe is needed! 

The energy transition: What changes will be necessary 

at the political (including the global political), the social 

and the ecological level to enable us to talk realistically 

of a “transition”? 

Linn: Politics should deal more sensitively with topics like 

taxes, e.g. by supporting photovoltaics! This should rather 

include support of economization (insulation) and alternative 

concepts than of generation. Low-temperature waste 

heat utilization in case of minor waste heat generation in 

industry and the private sector should not be ignored. I 

would be happy if the acceptance of reservoirs, energy 

transport lines and final repositories would be wider. 

And your wishes from the federal government in this 

context? 

Linn: Not only power but also money for the “big ones”. 

In addition to that, small, innovative ideas should be supported 

faster and especially unbureaucratically. As well as 

more equity between big and small companies. 

There are at least two problems with renewable energy 

sources: the lack of infrastructure and the continuing 

and persistent concentration of the established channels 

on conventional forms of energy. Will this change 

in the foreseeable future? 

Linn: I think that it will not change before 2025 to 2030. Infrastructure 

will stay uncritical in case of reasonable isolated operation 

solutions at wide technology basis and mass application. 

* Interview conducted by Stephan Schalm and Sabrina Finke 


115

FOCUS ON Edition 7 

Irrespective of the form of energy and the technology 

used, many consider the term “energy efficiency” to be 

the key to the energy questions of the future. How do 

you view this subject? What do you consider to be the 

most important development in this field in the thermoprocessing 

technology industry? 

Linn: It was a clever mentor role of the VDMA! This subject 

needs top priority if you e.g. consider the consumption of 

thermal processes in German industry. Neither insulation, lowtemperature 

waste heat utilization nor optimal fuel burning 

technologies are unsolvable approaches. Fiscal aspects at the 

percentage energy saving would be motivating. 

What benefits do electrical process-heat routes offer in 

your opinion? 

Linn: Less exhaust gases, best optimization by control 

technology and sensors, no particle emission of refractory 

materials etc. 

How do you view developments for enhancement of 

energy efficiency? 

Linn: Too slow! Government and federal states support 

the wrong areas. It will take again ten years until all operators 

of thermoprocess technology really start off. The reason: 

People shy away from the costs. 

In your opinion, how will energy consumption 

in industry, commerce 

and domestic households 

change? 

Linn: Well, I think there will be 

a decrease of 2 to 3 % per 

year in the next decade! 

What role does your company currently play on the 

energy market? 

Linn: An unimportant role, as we manufacture electrical 

furnaces (resistance-, inductive- and microwave-heated furnaces). 

We were the first ones in Germany who, for example, 

insulated high temperature furnaces with ceramic wool to 

save energy. For six or eight years, however, we have been 

working on new processes, furnaces, which will now be 

launched on the market. 

What role will your company be playing on the energy 

market in twenty year’s time? 

Linn: A more significant role! One of our start-up associate 

companies will massively launch new products by new 

efficiency technologies in the following years (va-Q-tec). 

What will be your company’s most important innovation 

or project? 

Linn: We have invested a lot of time and money in 

microwave drying for nuclear waste. This will be an 

important subject in the next ten years. Furthermore, 

due to lightweight design, we are dealing with the subject 

carbon fibre/basalt fibre and, of course, also with the 

subject rare earths. We are well-known for our small precision 

casting units and have done a lot for the materials 

Titanium and Titanium Aluminides which are considerably 

penetrating the market and are just about to finish 

the development phase (Turbine wheels/ Turbocharger 

wheels). 

What challenges do you see approaching you (economic, 

technological, social, etc.)? 

Linn: From an economic point of view, we are too small 

"The acceptance of 

reservoirs, energy 

transport lines and 

final repositories 

should be wider." 


Edition 7 

FOCUS ON 

RESUME 

Dipl.-Ing. Horst Linn sen. 

Date of birth: 26 th of July 1944 

Current job: Managing director of Linn High Therm GmbH 

Studies: 

Studied electrical engineering in Frankfurt a. M. and Munich 

Career: 

- Independent entrepreneur since 1969 

- Shareholder Induktio d.o.o., Ljubljana (Slovenia) 

- Member of the board of directors of VDMA/TPT 

- CEO of Ostbayrisches Technologie Transfer Institut (OTTI) 

- Member of the committee AiF – Arbeitsgemeinschaft industrieller 

Forschungsvereinigungen „Otto von Guericke“ e.V. 

- Supervisory board member „S-ReFIT AG (risk capital fund)“, 

Regensburg 

- Owner of more than 90 patents 

Languages: English, French 

Hobbies: motor sports, cooking 

married, two children 

to realize quickly all our ideas: Simply, we do not 

have enough money as in the past, we were very 

restrained regarding subsidies. Technologically 

seen, I am not afraid – on the contrary! Socially 

seen, we have done what was expected from us 

respectively me. But: too many competitors work 

hard to pull know-how from us! 

How do the expansion of the EU and globalization 

affect your company and its business? 

Linn: Partly positively, partly negatively. Chances 

and risks are still equal – in five to ten years it will 

become worse. 

How important is a trade name or a brand for 

the success of products in the industrial sector? 

Linn: Very important. Our policy is: We (often) 

receive what our competitors are not able to do 

or what they do not want to do for risk. 

Have you been unable to pursue developments 

or able to pursue them only after a delay or at 

reduced speed due to the lack of qualified personnel? 

Linn: Yes, there are two reasons: 1. Engineers are 

attracted by big companies due to salaries and 

additional contributions. A “small” company often 

cannot compete with that. 2. There is a lack of 

education for niche industries at universities of 

applied sciences and universities. 

Does a management team need greater media 

capabilities in order to convince investors? 

Linn: Of course! To hide your light under a bushel 

is no longer acceptable. Unfortunately, it is still 

easier to acquire € 20 mio. than € 2 mio. The New 

Market still continues to have an effect, especially 

in case of banks and planners of subsidiary programs 

(politics). 

What would you like to change in your company? 

Linn: Less talking but more responsible acting 

on a wide base. Less evaporation of know-how. 

How important is expansion abroad for your 

company? 

Linn: Only sales and service in countries which 

make sense to us. 

Is your company receptive to renewable energy? 

Linn: Yes. When we built the company 30 years 

ago, we already insulated better than regulations 

required. 


117

FOCUS ON Edition 7 

Does your company already use renewable energy? 

Linn: Yes, solar thermal energy, waste heat and a CHP. 

How receptive is your company to new technologies? 

Linn: Very receptive, because: That is what we live from 

and with! 

How much does your company spend on investments 

each year? 

Linn: Too much. During the economic crisis, this really 

caused us worry and deteriorated our rating. Unfortunately, 

top ideas are still undervalued in mechanical engineering. 

What has been/is your greatest energy-saving as a private 

person? 

Linn: A smaller car, a good insulation of the house, energyefficient 

household appliances etc. 

How would you assess your dealings with employees? 

Linn: Uncompromisingly clear and sometimes harsh but 

honest in all respects! In case of private problems, I am 

friend and helper. 

What do you think the people around you particularly 

appreciate about you? 

Linn: Honesty, working commitment, inspirational motor, 

helper in emergencies and my disproportionately good 

network. 

What moral values are of particular topicality for you? 

Linn: Important to me are justice, honesty, assumption 

of responsibility and, especially in case of problems, not 

to deny them! 

How do you manage to be sure of some time for yourself, 

and not always to be dealing with internal and external 

challenges? 

Linn: This is my biggest problem. I have too less holidays 

and time for my hobbies. As I am too good-natured, I can 

plan for myself the least. I am bad at saying no if someone 

else needs help or in accepting jobs. 

Do you, or did you, have any people whom you regard 

as examples to you? 

Linn: No. 

How were you brought up and educated? 

Linn: In a convent school. 

What is your motto for life? 

Linn: According to Don Bosco: “Be merry and let the sparrows 

sing.” But I am not always successful. 


Edition 7 

FOCUS ON 

In your opinion, what was the most important invention 

of the 20 th century? 

Linn: Semiconductor materials! 

What personal characteristics are 

most important to you? 

Linn: Openness. A look into the 

eyes helps. They are the mirror of 

the soul. 

When do you not think about 

your work? 

Linn: When I am sleeping or when I drive full throttle in 

a rallye car in order to reach the times of Walter Röhrl or 

Michael Stoschek. 

What is your own personal tip for upcoming generations? 

Linn: To learn more (basic knowledge) and not only to 

think of a good life, social networks and to think of retirement 

already when starting the career! Moreover, I think 

"Top ideas are 

still undervalued 

in mechanical 

engineering." 

that practical experience is very important from the beginning. 

Furthermore, next generations should also overcome 

to get rid of disciplinary limits and 

application domains. 

What has shaped you in particular? 

Linn: Convent school, motor sports, 

the obligation to earn money 

already as a student and to save 

money. 

What can you absolutely not do without? 

Linn: Work, rallye car, family, good food. 

What do you wish for the world? 

Linn: More justice, less dishonest/incapable politicians, 

respect between the religions! 

Thank you for this interview! 

Inductive Melting and Holding 

Fundamentals | Plants and Furnaces | Process Engineering 

The second, revised edition of this standard work for engineers, technicians 

and other practitioners working in melting shops and foundries is to appear 

in mid-2013. This new version of the title on inductive melting and temperature 

maintenance originally published in 2009 is the result of the great 

demand generated at that time, and includes coverage of the plant- and 

process-engineering advances achieved during the intervening four years. 

These relate, in particular, to the use of the induction furnace in electricsteel 

production, a field in which this environmentally and mains-friendly 

melting system has evolved into a genuine and advantageous alternative to 

the electric arc furnace. Characteristic of this is the recent increase in inverter 

supply power from its maximum of 18 MW at the time of publication of the 

first edition of the book to its present 42 MW to permit supply of 65 t crucible 

furnaces. 

Editor: E. Dötsch 

2nd edition 2013, approx. 300 pages, hardcover 

Order now: 

Tel.: +49 201 82002-14 

Fax: +49 201 82002-34 




FUTURE 

119


Flexible duct burner technology 

for process air heating 

he RatioStar burner is designed for on 

T ratio control for direct fired air heating. 

Basically the burner is fired at an excess air 

percentage of 15-30 %. Lower ratios and 

higher are possible. The RatioStar burner is 

a so-called duct burner and originates from 

the flue fire design. 

The flue fire burner is a burner designed 

for a specific application: a burner for supplement 

heat after gas turbines. This means 

it can handle extreme circumstances 

upstream as well as downstream the burner. 

A combination of high temperatures and 

low oxygen upstream the burner are typical 

circumstances which are difficult to handle 

by a standard burner. The flue fire burner is 

able to use this process air as combustion 

air, because of the design and construction 

of burner manifold and stabilization plates. 

The first RatioStar burners were developed 

based on the FFB-Design as air 

heaters. Where the flue fire is a burner 

which grabs the oxygen for combustion 

from the process air, the RatioStar will be 

provided with separate combustion air. It 

was found that the RatioStar would have 

the best performance when this combustion 

air flow would be controlled with 

the gas flow. 

In this way the RatioStar is used for air 

heat applications in which there was a 

desire for both gas and air control. Often 

in field air heat burners with fixed air and 

controlled gas are used. Disadvantage of 

these burners is less efficiency and moderate 

emissions in low fire, where the burner 

operates in high excess air. With gas and air 

control the excess air in low fire is substantially 

lower and the efficiency and emissions 

are improved significantly (Fig. 1). 

Typical applications for the RatioStar 

were under process conditions with high 

humidity and strict emission requirements, 

especially carbon monoxide. 

FEATURES 

The construction of the RatioStar is similar 

as the flue fire burner and is very unique. 

Many similar duct burners in the market 

are built from cast iron or aluminium bodies, 

which are bolted together to make 

stretches of burner ramps or even matrices 

of burners. The base of the RatioStar 

is not cast bodies, but a thick wall pipe. 

This pipe can be mild or stainless steel 

dependent on combustion air properties. 

This pipe is virtually indestructible and can 

be exposed to extreme circumstances. 

This pipe is the gas supply and manifold 

in which threaded holes are drilled and gas 

nozzles are screwed. The gas nozzle is also 

the fixture of the stabilization plate for the 

flame. The combustion air flows through 

the stabilization plate. This stabilization 

plate is a stainless steel plate and has special 

form openings which will create a swirl 

flow of air per each burner element. 

Fig. 2 clarifies the construction. The grey 

is the manifold pipe, the blue are the stabilization 

plates and the red are the gas nozzles. 

By making a Tee-connection on the pipe 

manifold it is possible to make cross connections 

from one row to the next. In this 

way we are able to make large matrices with 

multiple rows and in total high capacities. To 

maximum length of one manifold is about 

3 m, but with reinforcements this maximum 

could become even longer. 

Fig. 3 shows a large in-duct RatioStar. 

This burner consists of 6 rows with each 12 

modules. 

In this particular example there is one 

complete burner which fires in one part. The 

RatioStar can also be built in parts, where 

each part (row) can be fired separately. In 

this way the turn down can be increased. 

The capacity of the burner is expressed 

in 125 kW / module. The large burner in the 

picture has a nominal capacity of 9.6 MW. 

In-duct burners have a very large advantage 

in process air heating, where the main 

advantage is the excellent heat distribution 

in the air stream with a very short flame. The 

fact that the burner is mounted in the duct 

is beneficial to the space which is needed 

for the heat supply. 

Fig. 1: A straight RatioStar in low fire Fig. 2: Basic construction of the burner Fig. 3: Large in-duct RatioStar 



In field gun style burners need more 

space, because these require a separate 

chamber in which the flame resides. Then 

the hot flue gases and the process air needs 

to be mixed after the burner chamber to 

get acceptable temperature uniformity. 

The RatioStar burner is an on-ratio controlled 

burner, but it is very flexible in the 

required gas / air ratio. The best performance 

of the burner is reached at 20-30 % 

excess air, but the burner is able to withstand 

10-100 % excess air (Fig. 4). 

This flexibility is an advantage for setting 

up and operation of the burner. Within this 

window the burner operates stable and reliable. 

The control of the gas and the air is 

done by mechanical or electrical linked 

valves. 

Fig. 4: Window of operation of the RatioStar 

APPLICATION ADVANTAGES 

The result of this type of stabilization plate is 

a swirling flame, which starts from the nozzle 

and swirls upward. The flame stabilizes 

on the swirl, without making real contact 

with the stabilization plate. The location 

of the stabilization stays in place over the 

whole turn down. 

In Fig. 5a and 5b there can be seen a 

CFD simulation showing the mixture composition 

at low and high fire of the burner. 

This shows that at both situations the mixture 

is flammable right to the stabilization 

plate. Obviously, the flammable region in 

high fire is larger. 

Because of the strong stabilization properties 

of the burner, this burner is very flexible. 

The quality of the combustion air, but 

also the amount of combustion air can be 

variable. The burner practically only needs 

the combustion air for oxygen supply, which 

means it can work in process air with very 

low oxygen or high humidity. Also the combustion 

air may have a relative high amount 

of humidity. 

Tests have been done in the Gouda laboratory 

with the burner in which the stability 

was checked with combustion air of 130 °C 

and up to 165 g water/kg dry air. Stability and 

UV signal was not affected by the humidity of 

the combustion air. Fig. 6a and 6b are pictures 

of the test in which can be seen that the 

flame appearance is significantly different. 

As the burner is a derivate from the flue 

fire, it is able to use preheated air without 

problems. Limitations on the temperature 

of preheated air are based upon material 

properties. In practice the maximum which 

Fig. 5a: Simulation in low fire 

Fig. 5b: Simulation in high fire 


121


Fig. 6a: Flame with ambient air 

Fig. 6b: Flame with humid air 

has been used is up to 300 °C temperature of 

the combustion air. 

The process temperature can also be relative 

high for an air heat burner. Maximum 

experience in the field is 800 °C, but higher 

temperature can be used as well because 

the flue fire is able to handle up to 1,000 °C. 

The RatioStar has low emissions especially 

the CO is according the highest requirements 

when the burner is running on-ratio 

at 20-30 % excess air. The NO x for the Ratio- 

Star is also low. 

Fig. 7: Emissions from the RatioStar 

The emissions shown in Fig. 7 are measured 

in our laboratory in which circumstances are 

controlled and monitored. In short following 

applications can be considered for the RatioStar: 

■■ 

■■ 

■■ 

Low oxygen process air flows that have 

to be heated up. 

Air flows with high inlet temperatures 

up to 600 °C, where standard air heating 

burners cannot be used. 

Air heating processes that requires optimum 

combustion efficiency (on ratio 

control). 

■■ 

■■ 

Processes that require low emissions for 

CO, NO x and unburned hydro carbons. 

Optimum heat distribution in process 

air flows. 

APPLICATIONS – 

GYPSUM, ASPHALT, PAPER, 

FOOD 

Gypsum board dryers – Eclipse Combustion 

has supplied several projects with 

RatioStar burners for gypsum board dryers. 

These applications have roughly two distinctive 

variations: the longitudinal 

dryer and cross flow dryer. The 

first dryer uses large, centralized, 

heat sources and the second 

uses smaller, decentralized, heat 

sources. This means the longitudinal 

dryer has typically three 

zones with each one large induct 

burner and the cross flow 

dryer has many (20-50) smaller 

burners on mounting plates. 

These burners are hanging top 

to bottom in the dryer, but firing 

horizontally (topplates). 

For both types Eclipse 

Combustion has supplied 

RatioStar burners. Often the 

smaller topplate burners are 

controlled with mechanical 

linked valves, whereas the 

large in-duct burners are controlled 

by electronical linked 

valves. 



Fig. 8: Overview of asphalt recycling plant 

with RatioStar burner 

Gypsum Calciners – Eclipse Combustion 

has also supplied RatioStar burners for 

hot air generation for calcining processes 

to reach compact design and high temperature 

uniformity. 

Advantage for this application is the possibility 

to control gas and air, instead of firing 

with fixed air. This gives the end-user optimal 

possibility to control the process dryer. 

Another advantage is the possibility to use 

humid, pre-heated air as combustion air. 

Asphalt recycling – In the beginning 

of 2012 Eclipse Combustion has supplied a 

large in-duct RatioStar burner for a unique 

application in the Netherlands. This project 

by Volker Stevin Materieel (VSM) Dordrecht, 

in cooperation with KWS Infra and the 

Swiss company Amman, is an installation 

for asphalt treatment for recycling asphalt in 

which the normal direct heating by a large 

burner is now done by indirect heating. The 

system is called HERA (Highly Ecological 

Recycling Asphalt System). This means that 

the heat for the treatment is transferred indirectly 

after it is produced in a large air heater. 

This indirect air stream is recirculated, which 

means that the process air stream ultimately 

has very low oxygen (< 5 %) and has a relative 

high temperature. The inlet temperature 

for the burner is 320 to 350°C and upstream 

the burner it must be up to 800 °C. 

The combustion air for the RatioStar is 

preheated by the exhaust of the recirculation 

to a temperature of approximately 

285 °C. 

Purpose of this indirect treatment is more 

energy efficient production (less CO 2 ), 100 % 

recycling and no unwanted odours from the 

plant. Another big advantage of this indirect 

system is the better continuity of the quality 

of the asphalt. With the direct heating 

the quality of the product is affected by the 

flame and flue gases of the burner. 

Reason to choose the RatioStar for this 

application is the ability to control gas and 

air, the use of preheated air and the low oxygen 

and high temperature of the process 

stream. Another big advantage is the possibility 

to make this burner in-duct, which 

means ultimately a very compact built for 

this application. Fig. 8 shows a complete 

asphalt treatment plant in Rotterdam. 

Paper drying – Because of the same 

advantages of the RatioStar in gypsum 

board drying, this burner could also be 

well applied in the paper industry. The high 

efficiency, because of gas and air ratio controlled, 

the high flexibility, with preheated 

air, and the reliability in unfriendly environments 

with low oxygen make this burner 

ideal for any drying process. Also the low 

emissions from the RatioStar are often a 

requirement for the paper industry. 

Contact: 

Eclipse Combustion B.V. 

Ad Heijmans 

Gouda, Netherlands 

Tel.: +31 (0) 182 / 556-225 

aheijmans@eclipsenet.com 

Visit us at the HK 2013 

Vulkan-Verlag 


09 - 11 October 2013 

Rhein-Main-Hallen, Wiesbaden 

Germany 


123

INDEX OF ADVERTISERS 

INDEX OF ADVERTISERS 

Company 

Company 

Page 

Page 

AFC-HOLCROFT, Wixom, Michigan, USA 

4th International Cupola Conference 2012, Dresden, 63 

43 

Germany AICHELIN Holding GmbH, Mödling, Austria 35 

AICHELIN ALUEXPO Holding 2013, Istanbul, GmbH, Turkey Mödling, Austria Back Cover 27 

ALUMINIUM Bürkert GmbH 2012, & Co. Düsseldorf, KG, Ingelfingen, Germany Germany 32 15 

ALUMINIUM Elster GmbH, CHINA Osnabrück, 2012, Germany Shanghai, People’s 21 07 

Republic of China 

EMO Hannover 2013, Hannover, Germany 

ANDRITZ Maerz GmbH, Düsseldorf, Germany 

Expogaz 2013, Paris, France 

13 

82 

68 

ANKIROS 2012 / ANNOFER 2012 / TURKCAST 2012, 22 

Istanbul, FABTECH Turkey 2013, Chicago, USA 

Bloom GH Electrotermia Engineering S.A., (Europa) San Antonio GmbH, de Düsseldorf, Benagéber, Spain 11 

Germany ifm electronic GmbH, Essen, Germany 

103 

87 

13 

Elster Ipsen GmbH, International Osnabrück, GmbH, Germany Kleve, Germany 07 39 

JSC “Nakal – Industrial Furnaces”, 

Solnechnogorsk, Moscow, Russia 21 

Company 

Company 

Page 

Page 

Euro 

Linn 

PM2012, 

High Therm 

‚Basel, 

GmbH, 

Switzerland 

Eschenfelden , Germany 

88 

47 

FIB 

LOI 

BELGIUM 

Thermprocess 

s.a., Tubize 

GmbH, 

(Saintes), 

Essen, 

Belgium 

Germany 

front 

15 

cover 

HEAT 

Optris 

TREATMENT 

GmbH, Berlin, 

2012, 

Germany 

Moscow, Russia 27 

19 

JASPER 

Process-Electronic 

Gesellschaft 

GmbH, 

für Energiewirtschaft 

Heiningen, Germany 

Front Cover 

und Promat Kybernetik GmbH, mbH, Ratingen, Geseke, Germany Germany 

31 

11 

LOI schwartz Thermprocess GmbH, Simmerath, GmbH, Essen, Germany Germany 61 41 

SECO / Warwick Europe THERMAL S.A., S.A., Swiebodzin, Swiebodzin, Poland Poland inside front 35 cover 

Siemens SMS Elotherm AG, Rastatt, GmbH, Germany Remscheid, Germany back 93 cover 

SMS uni-geräte Elotherm gmbh, GmbH, Weeze, Remscheid, Germany Inside Front Cover 23 

Germany 

Wire / Tube Southeast ASIA 2013, Bangkok, Thailand 18 

Uni-Geräte GmbH, Weeze, Germany 25 

Business Directory 125-147 

International Magazine for Industrial Furnaces, 



your contact to the 

heat processing team 

Managing Editor: 

Dipl.-Ing. Stephan Schalm 

Phone: +49 201 82002 12 

Fax: +49 201 82002 40 

E-Mail: s.schalm@vulkan-verlag.de 

Editorial Office: 

Annamaria Frömgen 

Phone: +49 201 82002 91 

Fax: +49 201 82002 40 

E-Mail: a.froemgen@vulkan-verlag.de 

Advertising Sales: 

Bettina Schwarzer-Hahn 

Phone: +49 201 82002 24 

Fax: +49 201 82002 40 

E-Mail: b.schwarzer-hahn@vulkan-verlag.de 

Advertising Administration: 

Martina Mittermayer 

Phone: +49 89 203 5366 16 

Fax: +49 89 203 5366 66 

E-Mail: mittermayer@di-verlag.de 

Editor: 

Thomas Schneidewind 

Phone: +49 201 82002 36 

Fax: +49 201 82002 40 

E-Mail: t.schneidewind@vulkan-verlag.de 

Editor (Trainee): 

Sabrina Finke 

Phone: +49 201 82002 15 

Fax: +49 201 82002 40 

E-Mail: s.finke@vulkan-verlag.de 

124 heat processing 4-2012 

www.heatprocessing-online.com

International Magazine for Industrial Furnaces 


xxx 

REPORTS 


2013 

Business Directory 

I. Furnaces and plants for industrial 

heat treatment processes ............................................................................................................................126 

II. 

III. 

IV. 

Components, equipment, production 

and auxiliary materials ......................................................................................................................................136 

Consulting, design, service 

and engineering ......................................................................................................................................................144 

Trade associations, institutes, 

universities, organisations ............................................................................................................................145 

V. Exhibition organizers, 

training and education ...................................................................................................................................146 

Contact: 

Mrs Bettina Schwarzer-Hahn 

Tel.: +49 (0)201 / 82002-24 

Fax: +49 (0)201 / 82002-40 

E-mail: b.schwarzer-hahn@vulkan-verlag.de 


www.heatprocessing-directory.com 

125

REPORTS Business Directory xxx 3-2013 

I. Furnaces and plants for industrial heat treatment processes 

thermal production 

Melting, Pouring, casting 

126 heat processing 3-2013 4-2012

3-2013 Business xxx Directory REPORTS 


Powder metallurgy 

Heating 

4-2012 3-2013 heat processing 

127



Heating 




Heat treatment 

More information available: 



129










131




cooling and Quenching 




surface treatment 

Joining 




133



Joining 




recycling 

energy efficiency 

retrofit 

Powered by 

INTERNATIONAL 

THERM 

PROCESS 

SUMMIT 






Congress Center Düsseldorf, Germany 

Organized by 

09-10 July 2013 www.itps-online.com 


135


II. Components, equipment, production and auxiliary materials 

Quenching equipment 

Fittings 

Burners 

transport equipment 

Your contact to 

HEAT PROCESSING 


Tel. +49(0)201-82002-24 

Fax +49(0)201-82002-40 

b.schwarzer-hahn@vulkan-verlag.de 





137



Burner applications 

Burner equipment 

Your contact to 

HEAT PROCESSING 


Tel. +49(0)201-82002-24 

Fax +49(0)201-82002-40 

b.schwarzer-hahn@vulkan-verlag.de 




Hardening accessories 




139



resistance heating 

elements 

casting and melting 

accessories 

inductors 




Measuring and automation 


141



Measuring and automation 

Power supply 




cleaning and drying 

equipment 

refractories 









143


III. Consulting, design, service and engineering 


III. Consulting, design, service and engineering 


å 

IV. Trade associations, institutes, universities, organisations 


145


V. Exhibition organizers, training and education 

Powered by 

146 

INTERNATIONAL 

THERM 

PROCESS 

SUMMIT 








Organized by 

09-10 July 2013 www.itps-online.com 


xxx 

REPORTS 


147

COMPANIES PROFILE 

Bürkert Fluid Control Systems 

Bürkert Fluid Control Systems 

Contact: 

Maik Lösel 

Tel.: +49 (0) 7940 / 10-0 

info@burkert.com 

COMPANY: 

Bürkert Fluid Control Systems GmbH & Co. KG 

Christian-Bürkert-Str. 13-17 

74653 Ingelfingen 

Germany 

BOARD OF MANAGEMENT: 

Heribert Rohrbeck (CEO) 

HISTORY: 

Bürkert was founded in Germany in 1946 by Christian Bürkert, who 

began by developing and manufacturing innovative products 

such as foot warmers, oven controls and thermal control systems 

for incubators. While these products met the needs of the time, 

over the years the company increasingly focused on valve technology 

and soon became an international benchmark for industrial 

solenoid valves. 

With his combination of vision, innovation and enormous energy, 

Christian Bürkert succeeded in building an enterprise that is today 

known for fluid control systems, offering everything from simple 

valves to high-tech sensors, all manufactured to highest quality 

and applying state-of-the-art technology. Unfortunately, Christian 

Bürkert lost his life in a plane crash in 1971 and didn’t live to see 

the realisation of his vision. 

However, his pioneering spirit lives on in the family-owned company, 

and it is evident in the motivated employees who contribute 

their skills, knowledge and ideas to maintain Bürkert’s position as 

a market leader, day after day. 

NUMBER OF STAFF: 

More than 2,400 worldwide 

EXPORT QUOTA: 

80 % in 2012 

PRODUCT RANGE: 

The success of Bürkert as a leading manufacturer of control, measuring 

and closed loop systems for fluids and gases is based on continuous 

customer-oriented innovation and our engineering competence located 

in five Systemhouses. It means a wide range of valves, sensors and controllers 

as well as integrated customized systems and fully automated 

solutions, with regard to leading edge construction and communication 

technology. 

Product ranges are: Solenoid valves, Process and Control valves (incl. BBS 

& Robolux), Pneumatics, Sensors, Transmitters, Controllers, Micro Fluidics, 

MFC/ MFM, LFC/ LFM and Proportional valves. 

COMPETITIVE ADVANTAGES: 

The company offers global experience in Fluid Control Systems you 

can rely on. Bürkert is an adaptable organisation with flexible processes. 

Each segment (water, gas, micro, hygienic) thereby combines a range of 

technologies or physical principles which are common across several 

traditional industries. 

CERTIFICATIONS: 

ISO 9001, EMAS, ISO 14001, BS OHSAS 18001, IECx, Druckgeräterichtlinie 

97/23/EG, RoHS & REACH, ATEX 

SERVICE POTENTIALS: 

Servicing, maintenance, commissioning, … 

INTERNET ADDRESS: 

www.burkert.com 


3-2013 IMPRINT 


Volume 11 · Issue 3 · August 2013 

Official Publication 

Editors 

Advisory Board 

Publishing House 

Managing Editor 

Editorial Office 

CECOF – European Committee of Industrial Furnace and Heating Equipment Associations 

H. Berger, AICHELIN Ges.m.b.H., Mödling, Prof. Dr.-Ing. A. von Starck, Appointed Professor for Electric Heating at RWTH 

Aachen, Dr. H. Stumpp, Chairman of the Association for Thermal Process Technology within VDMA, CTO Tenova Iron & 

Steel Group 

Dr. H. Altena, Aichelin Ges.m.b.H., Prof. Dr.-Ing. E. Baake, Institute for Electrothermal Processes, Leibniz University of 

Hanover, Dr.-Ing. F. Beneke, VDMA, Prof. Y. Blinov, St. Petersburg State Electrotechnical University “Leti“, Russia, René 

Branders, President of CECOF, Mike Debier, CECOF, Dr.-Ing. F. Kühn, LOI Thermprocess GmbH, Dipl.-Ing. W. Liere-Netheler, 

Elster GmbH, H. Lochner, EBNER Industrieofenbau GmbH, Prof. S. Lupi, University of Padova, Dept. of Electrical Eng., Italy, 

Prof. Dr.-Ing. H. Pfeifer, RWTH Aachen, Dipl.-Phys. M. Rink, Ipsen International GmbH, Dipl.-Ing. St. Schalm, Vulkan-Verlag 

GmbH, M.Sc. S. Segerberg, Heattec Värmebehandling AB, Sweden, Dr.-Ing. A. Seitzer, SMS Elotherm GmbH, Dr.-Ing. P. Wendt, 

LOI Thermprocess GmbH, Dr.-Ing. J. G. Wünning, WS Wärmeprozesstechnik GmbH, Dr.-Ing. T. Würz, CECOF 

Vulkan-Verlag GmbH, Huyssenallee 52-56, 45128 Essen, Germany 

P.O. Box 103962, 45039 Essen 

Managing Directors: Carsten Augsburger, Jürgen Franke 

Dipl.-Ing. Stephan Schalm, Vulkan-Verlag GmbH 

Tel. + 49 201 820 02-12, Fax: + 49 201 820 02-40 

E-Mail: s.schalm@vulkan-verlag.de 

Annamaria Frömgen, Vulkan-Verlag GmbH 

Tel. + 49 201 820 02-91, Fax: + 49 201 820 02-40 

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