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2007 Volume 4 Issue 1HOT DIP GALVANIZERS ASSOCIATION Southern Africa30Featuring:Life cycle costing analysis on industrial coatingsDurability of continuous galvanized sheeting for light steel framed structuresIntroduction to SASFACase study – Evaluating logistics wrt the use of hot dip galvanizingCoating reports

HOT DIP GALVANIZERS ASSOCIATION Southern AfricaFeaturing:Life cycle costing analysis on industrial coatings2007 Volume 4 Issue 130HOT DIPGALVANIZINGOfficial journal of the Hot Dip Galvanizers Association Southern Africa • 2007 Volume 4 Issue 1CONTENTSTODAY30Durability of continuous galvanized sheeting for light steel framed structuresIntroduction to SASFACase study – Evaluating logistics wrt the use of hot dip galvanizingCoating reportsISSN 1023/781XThe Association is a technicalinformation centre established forthe benefit of specifiers,consultants, end users and itsmembersPUBLISHED BY:Hot Dip Galvanizers AssociationSouthern AfricaQuality House, Unit U4,St. Christopher Road,St.Andrews, BedfordviewP.O. Box 2212 Edenvale 1610Tel: (011) 456-7960Fax: (011) 454-6304Email: hdgasa@icon.co.zaWebsite: www.hdgasa.org.zaSaskia Salvatori:Office ManagerEmail: hdgasa@icon.co.zaOlive Akim:ReceptionistEmail: info@hdgasa.org.zaBob Wilmot:Executive DirectorCell: 082 325 8840Email: bob@hdgasa.org.zaTerry Smith:Editor & Technical MarketingDirectorCell: 082 893 3911Email: terry@hdgasa.org.zaWalter Barnett:Executive ConsultantCell: 082 891 5357SUB-EDITOR, ADVERTISING &SALES:Anne van VlietTel: (011) 462-5073Cell: 082 775 0711Email: mwvliet@mweb.co.zaDESIGN AND LAYOUT:Sandra AddinallTel: (011) 868-3408Fax: (011) 900-1922Email: cbtdesign@adcot.co.zaREPRODUCTION ANDPRINTING:Camera PressTel: (011) 334-3815Fax: (011) 334-3912Email: cpress@iafrica.comViews expressed in articles andadvertisements are not necessarily theviews of HDGASA.Articles or extracts thereof may bereproduced provided full acknowledgementis given.Advertisers’ Index.................................................................................................................................................... 27RegularsExecutive Director’s Comment........................................................................................................................................ 2Note from the Editor ........................................................................................................................................................ 2Miss Conceptions ................................................................................................................................................................ 23Duplex Coatings:A life cycle costing analysis comparing painted steel, hot dip galvanizing and duplex coating systems........ 24Duplex Coating Report:Duplex coated verandah columns at Parklands Shopping Centre – Cape Town ............................................ 28Coating Report:Wet storage stain and subsequent red rust to the hot dip galvanized sheeting on a slag crushing plant ........ 30Walter’s Corner .................................................................................................................................................................. 33Member’s News:Zincor to undertake the rebuild of the number 4 roaster .................................................................................. 37Robor acquisition finalised .......................................................................................................................................... 38Personality Profile ................................................................................................................................................................ 39Guest Writer ........................................................................................................................................................................ 42Case Study N°13.................................................................................................................................................................. 43Feature – Continuous hot dip galvanized sheetingSouthern African Light Steel Frame Building Association (SASFA) .......................................................................... 4Introduction to ARTF and Roof Technology Services (RTS) .................................................................................... 6Durability of galvanized sheet in light steel frame buildings...................................................................................... 7The family of zinc, zinc-aluminium and duplex coated coiled sheeting .................................................................. 10Durability of hot dip galvanized sheeting exposed to general atmospheric conditions .................................... 12Major new player in lightweight steel frame building industry ................................................................................ 14The fasteners required for light weight steel framed buildings ................................................................................ 16Feature – Safety and security including continuous galvanizing of wireAndrew Mentis plays it safe at Marion Island .............................................................................................................. 18Van Ryssen Dam, Phalaborwa .......................................................................................................................................... 20Focus on security ................................................................................................................................................................ 21Wire galvanizing specifications revised .......................................................................................................................... 222007 Hot Dip Galvanizing AwardsCall for nominations............................................................................................................................................................ 35GeneralObituaries .............................................................................................................................................................................. 16Coating inspector’s course ................................................................................................................................................ 29Bread is now fortified with zinc!...................................................................................................................................... 40Front Cover: Kaleidoscope of products used in safety and security and continuous hot dip galvanized sheet and wire.Hot Dip Galvanizing – Adding value to Steel

CommentsExecutive Director’sCommentAt the start of anew year, it is wellto reflect on thestate of theindustry and theroll of theAssociation. Ourprimary goal is oneof dedication to theimprovement ofservice and qualityto the wider industry, and as a technical andmarketing support organization to ourmembership.As result of the substantial increase in thebasic price of zinc, and the fact that over thepast 6 to 8 months, we have witnessed asignificant demand for hot dip galvanizing,market place perception or rumors have itthat hot dip galvanizing has become tooexpensive and secondly that the industry, asa whole, does not have sufficient capacity tomeet current demand.Perception can be misleading and the twoissues highlighted above are no exception.As published in past issues of Hot DipGalvanizing Today, the zinc price is related tothe London Metal Exchange (LME) price inUS$. With reference to published dataavailable on the web, the US$ price has comeoff a high of over $4 500 per ton and is nowtrading under $3 400 per ton. Irrespective ofthis change, no time over the past year can itbe said that hot dip galvanizing wasuneconomical when comparing corrosionperformance based criteria. Rand for Randand corresponding environmental conditions,hot dip galvanizing remains economicallycompetitive with other forms of corrosioncontrol coatings.Turning to the issue of capacity constraints.It is true that there is now far less freecapacity available than in previous years.However, substantial capacity remainsavailable within the total industry. What isrequired, more so than in the past, is thatplanning and liaison between projectmanagers, consultants, steel fabricators andgalvanizers must take place in order toallocate production capacity to the variousprojects. Such forward planning will assistour industry to achieve turn around timesand meet project requirements.Bob WilmotNote from theEditorDue to increased activities in the mining and industrialsectors over the last six months, an unusually higherdemand for hot dip galvanized steel particularly inGauteng has been experienced. Substantially increaseddemand is however, not the only thing that can influencedelivery of quality coatings by the industry.Every day due to work pressures and failed deadlines the galvanizers are requested that infavour of a more acceptable delivery time, they forgo fettling and cleaning before delivery. Ifacceptable by the galvanizer, then cleaning is carried out by the contractors at their yard orworse at the site. Although many contractors have been doing this successfully for sometime, those making use of relatively untrained personnel to mechanically clean hot dipgalvanized coating imperfections, etc. can very easily result in inappropriate over cleaningof the coating, leading to unacceptable quality and premature surface discolouration.The end user can obviate this practice by insisting on a SABS certificate of conformance,whereby the galvanizer is forced to complete all cleaning in terms of his quality controlprocedure in the promised time, prior to delivery.Without adequate control, the practice of over cleaning by uninformed personnel can havemajor long-term repercussions for this industry.Features for this issue include:Continuous Hot Dip Galvanizing of Sheeting, including articles by the Advanced RoofingTechnology Foundation (ARTF); the establishment of the South African Light Steel FrameBuilding Association (SAFSA) and its objectives, a sheeting producer and a contractorscomments; an article on the family of Zinc, Zinc/Aluminium and Duplex Coated CoiledSheeting; a comment on SANS 1273, Fasteners for roof and wall coverings in the form ofsheeting; as well as a coating report dealing with the implications of wet storage stain onsheeting during lengthy storage.Continuous Hot Dip Galvanizing of Wire and Safety and Security, includes landrehabilitation at Van Ryssen Dam; the safety and security of an electrified fence and newgalvanized wire specifications; and Andrew Mentis plays it safe at Marion Island.Under Duplex Coatings, we look at life cycle costing analysis, an essential prerequisite forany specifier; Education and Training expands on our certificated coating inspectors coursewhich, from an engineering perspective, is now CPD approved and an essentialrequirement in any coating inspectors portfolio.Following previous discussions on the superior long-term sacrificial protection propertiesprovided by Hot Dip Galvanizing, the hot debate on ”Zinc Rich Paint” versus “Hot DipGalvanizing” seems to have abated?Duplex Coating Report, stresses the need for surface cleaning of the hot dip galvanizingprior to the application of paint, seen at a shopping centre in the Western Cape.Other regular articles include “Misconceptions”, where Miss Conception sets the recordstraight on market-place misconceptions; “Walter’s Corner” addresses the state of the hotdip galvanizing industry; Our Guest Writer, Bob Andrew dons his philosophical hat with hisarticle on “Quantum Theory”.Our Personality Profile, is Busi Mpontshame our first female “hot dipper”.Finally, “Case History No 13” includes the Moma Sands Project – with an emphasis on thelogistics of the project and advantages of using hot dip galvanizing.Should a reader wish to express an opinion or provide us with an article, kindly contact me– enjoy the “magazinc”.Terry Smith2 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

PROUDLY SUPPLYING SOUTH AFRICA’SSTRUCTURAL STEEL REQUIREMENTS FOR AVARIETY OF PROJECTSHEAD OFFICE: STEELWORKSP.O. Box 111 Witbank 1035, Mpumalanga, South AfricaTel.: National (013) 690 9911 International +27 13 690 9911Fax: National (013) 690 9033 International +27 13 690 9033DOMESTIC SALESP.O. Box 994 Bedfordview 2008, Gauteng, South AfricaPellmeadow Office Park, Block B – 1st Floor,60 Civin Drive, BedfordviewTel.: National (011) 663-0280 International +27 11 663 0280Fax: National (011) 454 0705 International +27 11 454 0705(011) 454 0576 +27 11 454 0576EXPORT SALES & ORDER SERVICES,STEELWORKSP.O. Box 111 Witbank 1035, Mpumalanga, South AfricaTel.: National (013) 690 9016 International +27 13 690 9016Fax: National (013) 690 9063 International +27 13 690 9063

Continuous hot dip galvanized sheetingmanufacturers of light steel frame building systems,distributors of material and equipment and the Institute.An action programme has been drawn up to prioritise themany tasks identified for establishment of this industryon a sound footing.Southern AfricanLight SteelFrame BuildingAssociation(SASFA)A new division of theSAISCIn order to assist with the development of the light steelframe building industry, an association has been formedas a division of the Institute of Steel Construction.Known as the Southern African Light Steel FrameBuilding Association (SASFA), its founder members arethe major material suppliers to this new industry : MittalSteel, Group Five / Everite (Fibre Cement Board), BPBGypsum and Lafarge Gypsum (Plaster Board), and OwensCorning and Brits Nonwoven (Insulation).The mission of SASFA is to develop and grow the SouthernAfrican and export markets for light steel frame building.Its vision is to make the following come true:◆◆Light steel frame building is established as a highquality, energy efficient, cost effective and preferredmethod of building in South Africa, for low riseresidential and non-residential buildings. The goal isto capture 10% of the market for new low risebuildings by 2011.Light steel frames constitute a significant exportindustry.A Steering Committee has been formed to guide thedevelopment of the Association and the industry, withrepresentatives from the major material suppliers,A number of other important milestones have alreadybeen, or are being achieved:◆◆◆◆◆◆An interim draft Code of Practice has been compiledfor light steel frame building, based on the approvedtimber frame code (SANS 10082), and it was acceptedin principle by the NHBRC (National Home Builders’Registration Council).A Technical Committee has been formed, with its firstpriority the drafting of a comprehensive SANSStandard for Light Steel Frame Building. A lot ofground has been covered, and the draft document istaking shape. It covers foundation requirements,structural aspects, and interior and exterior claddingand insulation of light steel frame buildings. TheSASFA draft is expected to be completed by earlyApril 2007.The Training Committee is responsible for theidentification of education and training requirements,the establishment of courses and the arrangement ofseminars.A logo has been designed, and the SASFA website(www.sasfa.co.za) established. Judging by the rapidlygrowing site visits statistics, it is proving to be avaluable source of information. The names andcontact detail of SASFA members have recently beenadded.A well attended and very successful cocktail functionwas held during October at the Country Club ofJohannesburg, where suppliers to this industry hadthe opportunity to exhibit some of their literature.Scheduled to end at 19:30, such was the enthusiasmof some of the attendees that discussions (and lateron some singing) went on until 23:00!A session of the Steel 50 Conference, arranged by theInstitute, was dedicated to light steel frame building.Some excellent papers were presented by twooverseas and a local speaker, and SASFA had its firstexhibition stand. Feedback from delegates indicatedthat this was one of the best rated sessions of theConference!◆ The first General Meeting of SASFA was held on 21February, and the Steering Committee for 2007elected. It was very well attended by interested partiesfrom all sectors of industry.4 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Continuous hot dip galvanized sheeting◆Papers have also been presented at the InternationalHousing Conference, arranged by the SA HousingFoundation and held in Cape Town during October.Invitations have been sent out to the wider industry tobecome members of SASFA, via membership of theInstitute. A range of membership categories are available:◆◆In order to ensure quality, preparation work is underway to establish an accreditation scheme of members.Audits will be held to establish conformance ofmembers against an agreed set of criteria, rangingfrom quality assurance certification (ISO),qualification and experience of technical staff,condition of equipment and software, to trainingprogrammes for employees.A Quality Checklist has been drafted, to assistbuilders and building inspectors to ensure thatbuilding work is carried out according to specification.◆◆◆◆◆Profilers and manufacturers of light steel frame buildingsystems.Major material suppliers (steel, fibre cement,plasterboard and insulation).Other material, component and equipment suppliers.Professional members (architects, engineers, quantitysurveyors & draughtspersons).Merchants, service centres and distributors.◆Contact has been established with the financingindustry, to facilitate acceptance of light steel framebuildings.◆◆Building industry members.Associate members, and◆ Widespread media coverage is being achieved –articles on light steel frame building have appeared inSteel Construction, Walls and Roofs, EngineeringNews, Gauteng Business, and SA Builder, to name buta few of the more prominent publications.◆individuals.Further detail, and membership application forms andapplicable fees can be obtained from www.sasfa.co.za.Alternatively, enquiries may be directed to info@sasfa.co.za.Specialists inhot dip galvanizingwith quick turnaround timesHOT DIP GALVANIZINGTO APPROVED QUALITYSTANDARDS20 Dekenah StreetAlrode 1449P.O. Box 124581Alrode 1451Tel.: (011) 908-3411(011) 908-3418(011) 908-3420Fax: (011) 908-3329Volume 4 Issue 1 2007 Hot Dip Galvanizing Today 5

Continuous hot dip galvanized sheetingIntroduction to ARTF andRoof Technology Services (RTS)Walter Barnett is the founder and an honorary lifetime member of the Hot Dip Galvanizers Association of Southern Africa. He hashad a long and illustrious career in the corrosion control field, having acquired a number of honorary titles and awards for hisachievements.Mr Barnett has twice served as President of the Corrosion Institute, and was Executive Director of the Hot Dip Galvanizers’Association of Southern Africa (HDGASA). He is a gold and silver medal award winner of the Corrosion Institute, and was appointedas their Vice Chairman in 2003. He is still very active as a senior advanced technical consultant in the fields of corrosionprotection, coatings and galvanizing.Mr Barnett is currently listed as a senior ARTF advisory panel member (independent) and has written the following introduction forARTF and RTS:The Advanced Roof Technology foundation Of SouthernAfrica (ARTF) has established over the years acommendable reputation as Southern Africa’s leadingand benchmark setting non-profit organization in thefield of roofing care and remedial maintenance.The ARTF advisory panel includes associates who haveall established nationwide reputations for extensivetechnical knowledge, experience and professionalcompetence, which has been acquired over many yearsof service in the public sector, prior to their retirement.ADVERTORIALROOF TECHNOLOGY SERVICESOffering CSIR/SABS/HDGASA/ISO etc. concept based specialty cost-saving roofing services to the corporate sectorOver the years, many technical authorities have passed comment on the problems associated with roof neglect, incorrect roof repairs andmaintenance, and on the liabilities and costs associated with roof sheeting corrosion, etc., eg:“As an example, the bill to repair, partially replace, upgrade and maintain a long neglected and weather damaged factory or warehouse roof, has frequently cost between one andfive million Rand! (in most cases, these costs could have been reduced by 60% or more…).” (Introduction to the 2006 ARTF Roof Users’ Manual).“The period of weathering (of a metal roof) should be limited so that no serious damage to the zinc layer occurs… two years is considered appropriate. (Conventional)painting of roof sheeting where corrosion of the steel has already occurred seldom provides long-term durability.” (CSIR technical information letter ref: BK 021/00 5600).As ARTF accredited specialist roofing consultants, RTS offer a viable long-term solution to this – their roofingservices include:■ Roof assessments and reports■ Advanced level CRT specifications for roof repairs and maintenance■ Assisting clients with the screening and appointing of ARTF approved specialist roofing contractors■ Professional roof project management and QA inspection services■ Maintenance plans, and cost control services.RTS offer a premium, specialised executive oriented service to pro-active corporate companies who themselvessupport the policies of “do it right from the start”, and “invest more now in the correct approach, to greatlyincrease future benefits and to limit future costs and liabilities.”Design errors and persistent leak problems solvedat Spar Nelspruit. RTS reset the roof structure and installed aleak-free “floating” roof-sheeting system.“These (CRT) systems are unique and invaluable in Southern Africa… They are the only complete, fully comprehensive, … field proven sets of advanced level remedialroofing …technologies, specifications, codes of practice etc. available locally at this time.” (Martin S. Smit – Chief Research Officer Boutek, CSIR – comment on CRT (ARTF/CSIR/ SABS/ HDGASA/ ISO etc. based) roof repair and maintenance specifications and systems, unique to ARTF/RTS).“… the owner would save… 37.5% per year...” (R.E. Cromarty, Chief Scientific Officer CSIR 1990, on how much can be saved by early, correct, regular roof maintenance).Tel: 011 605 2510 Facsimile: 011 605 2511 Email: info_artf@mweb.co.za / tanya.rts@iburst.co.za

Continuous hot dip galvanized sheetingThe panel includes Ron CromartyCSIR research scientist, GordonMunro retired S.A.B.S. Paints andSealants Manager and Martin S Smitretired C.S.I.R. Boutek ChiefResearch Officer. Leading this teamof experts is Rick Norwood, ARTFfounder member and seniorremedial roofing technologist. It ismost unlikely that a team ofconsultants with a higher level ofethical standards, overall publicspirited helpfulness and extensivetechnical experience could be foundthan that available from this groupof veteran ARTF members.Mr. Rick Norwood is also managingmember of Roof Technology Services(RTS), which is a specialist-roofingconsultancy. Rick has workedextensively over the years tostreamline the vast technicaldatabase of ARTF into a simple andconcise user-friendly system thatcan be used and effectivelyimplemented by interestedexecutives, engineers, andmaintenance managers.The outcome of this work isreflected in the ARTF Global RoofAsset Protection Plan (AGRAPP)manual which offers a safe, secure,reliable and workable method which,if correctly applied will assistowners to escape the “vicious cycle”of roof problems (including leaks)which lead to exorbitant long-termmaintenance and replacement costs,the majority of which are corrosionrelated.Durability of galvanizedsheet in light steelframe buildingsBackgroundThe advent of light steel frame building in South Africa is one of the most excitingdevelopments in recent times in the steel and building industries. While thismethod of building has been used in the US, Europe and Australia for decades, ithas only recently been introduced to South Africa. It offers quality, cost andenergy efficiency, as well as speed of erection for low-rise residential and nonresidentialbuildings.Light steel frame building consists of structural wall frames and roof trusses,manufactured from cold-formed thin gauge galvanized steel sections. Highstrength galvanized sheet in thicknesses of 0.58mm to 1.2mm, with a Z275 zinccoating designation, is normally used.Exterior cladding can consist of a single skin brick wall or fibre cement board,fixed to the wall frames. Services – electricity and plumbing – are installed in thewall cavity created by the light steel frames, as is the insulation material. Gypsumboard, fixed to the light steel frame, is typically used for internal wall claddingand ceilings.Design and manufacturingThe key to the success and rapid growth of light steel frame building worldwidelies in the seamless interface between the computer based design and thecomputer controlled manufacturing facilities. Sophisticated software designprogrammes have been developed to carry out the structural design of eachelement required for a building, and to electronically convey the dimensionalspecifications to the roll-forming facility.Overall costs which can beattributed to corrosion amount toseveral billion Rand annually inSouth Africa alone. Corrosiondamage to roofing contributessignificantly to this costly situation.Here at last, we have a provenmethod whereby owners and tenantscan stem the tide of costly corrosionrelated degradation and damage toroofs and structures.Figure 1:The map uses ISO 9223:1992 Corrosion of metals and alloys – Corrosivity ofatmospheres – Classifications. A C1 classification indicates a low rate of corrosion, and C5M thehighest corrosion rate.Volume 4 Issue 1 2007 Hot Dip Galvanizing Today 7

Continuous hot dip galvanized sheetingDurability of the galvanized steelstructureClearly the durability of the galvanizedsteel sheet used to manufacture thelight steel frame sections is of utmostimportance, as the wall frames cannotbe accessed readily for inspection andmaintenance. The steel frame has to lastfor the design life of the building, toprevent expensive maintenance. Goodbuilding practice, as required by thedraft SANS Standard for Light SteelFrame Building, is required to ensurethat the frame members are not subjectto moisture, which could causecorrosion.samples were placed in wall cavities,the space between ceiling and roof aswell as basements of four light steelframed buildings in aggressive marine(as close as 400m from the sea) andindustrial environments. Samples wereremoved after one, three and fiveyears, for evaluation of zinc loss due tocorrosion.After 5 years they determined the lossof the zinc coating due to atmosphericcorrosion to be “negligible”, and basedon the results, calculated that thefunctional life of the galvanized steelelements will be in excess of 500 years!proximity of sources of aggressiveindustrial pollution. It should howeverbe noted that the exposed parts of thestructure – such as trusses and purlinsunder the eaves – may need additionalprotection against corrosion in marineor industrially polluted atmospheres. Anumber of different suitable paintsystems are available from reputablepaint suppliers.Visit www.sasfa.co.za for moreinformation on light steel framebuilding.J Barnard, SASFA, February 2007.Extensive long term tests have beencarried out in South Africa by variousorganisations such as the CSIR, Eskomand others on the functional life span ofgalvanized sheet in exposedapplications (such as roof cladding) andin a wide range of climate zones. Thecorrosion performance of galvanizedsteel is proportional to its coatingthickness and the corrosivity of theenvironment to which it is exposed, andis largely linear in nature. The results arewell documented, and the functional lifespan up to first maintenance can besummarized in Table 1 and figure 1.However, the map does not apply togalvanized sheet inside the buildingenvelope, largely protected from theexternal atmosphere - as in the case oflight steel wall frames and roof trusses.An indication of the durability ofgalvanized sheet in such a protectedenvironment can be obtained from theperformance history of ‘gang nail plates’(manufactured from galvanized sheet)which have been used to join timbertruss members for more than 50 years inall the Southern African climate zones.Out of the tens of millions of nail platesused, not a single failure of timbertrusses due to the corrosion of the nailplates have been documented by thecountry’s major truss manufacturer.To obtain scientific data, IZA(International Zinc Association), ILZRO(International Zinc Lead ResearchOrganization) and the US SteelFraming Alliance, conducted a five yearexposure test programme in NorthAmerica and Europe. Galvanized steelBased on Table 2, Mittal Steel SA feltconfident to issue a 50-year atmosphericcorrosion warrantee on their galvanizedsheet used inside the building envelope,subject to sound application practicesand certain conditions. The warranteeapplies to all structures erected 500m ormore from the sea, and not in closelife of coating in years90807060504030201000 10 20 30 40 50 60 70 80coating thickness, μmrural inland, C2urban inland/mildcoastal, C3industrial inland/urban coastal, C4polluted industrial/coastal, C5Table 1: Relationship between coating thickness and expected functional life of the zinc coating.AVERAGE LIFE SPAN IN YEARS BASED ON:Average 5-year Maximum single Maximum singlemass loss data* 5-year mass 5-year mass(Actual coating loss data loss dataSamples thickness) (Actual coating (Nominal coatingthickness)thickness)Galvanized 1 ** 1072 1055 839Galvanized 2 ** 682 628 541Zincalume / Galvalume 555 475 507Average 765 746 652* Samples with no corrosion (zero corrosion rate) were not used in calculating the averages.** Galvanized 1 : Z275 coating, Galvanized 2 : Z200 coatingTable 2.Editorial note:While extrapolation of 5 year test data to predicta functional life in excess of 500 years may be abit ambitious, it would appear that a Z275 zinccoating will protect the steel against corrosion forfar longer that the normal design lives ofbuildings, provided sound and correctconstruction practices are adhered to.8 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Continuous hot dip galvanized sheetingThe family of zinc, zinc-aluminium andduplex coated coiled sheetingDefinitionsCoil Coated Sheeting: Thin gauge steelsheeting produced in coil form,which is subsequently de-coiled,passed through a continuous metalcoating processing line and then recoiled.Duplex Coil Coated Sheeting: Coilcoated sheeting which is providedwith an organic paint coating over aninitially applied metal coating.Although hot dip galvanized profiledroof sheeting has performed verywell for many years both in SouthernAfrica and abroad, other protectivecoating systems have beendeveloped which can in manyapplications provide enhanced costeffective corrosion control.Before selecting the most effectivecoating system for a structure, it isessential to assess the degree ofcorrosion attack likely to beencountered in service. This will beinfluenced to a large extent byenvironmental conditions which arebroadly described as Coastal Marine(very aggressive corrosion), Industrial(aggressive corrosion) and Rural(benign to moderately corrosive).A further factor to consider is theextent to which corrosion inducingchemicals are produced or storedwithin a building and/ or thepresence of corrosive fumesproduced as a result of variousmanufacturing activities for whichthe building is used.The metal coating systems availablefor the protection of steel sheetingfall into three main categories:1. Zinc-aluminium alloy coated steelsheetingWhen it was recognized thataluminium in zinc increased itscorrosion resistance, the steelindustry developed a coating alloyconsisting of 55% aluminium, 1.5%silicon and the rest zinc. This productwas first produced by Bethlehem SteelCompany and marketed under thename Galvalume and subsequentlyZincalume (by Lysaghts). The sameproduct is now produced by othermanufacturers under names such asAlugalva, Aluzinc, Algafort andZalutite. The coating is applied onnon-oxidising continuous anneal hotdip coating lines to a wide range ofstrength levels.a) Corrosion Resistance:Relying on long term atmosphericexposure tests (acceleratedlaboratory tests are unreliable), ithas been established that thicknessfor thickness, the Galvalume typecoating provides a corrosionresistant coating between two tofour times that of pure zinc but withless cathodic protection and with theinherent problem of aluminium incontact with alkalis such as cement.Aluminium and zinc are described asamphoteric metals in that they reactaggressively at both low and high pHlevels. This is in contrast to steelwhere the corrosion rate decreasesas the pH increases. Aluminium istolerant down to pH levels of 3.6while above pH 8.6 it corrodes. TheCorrosion loss, micrometers15105GalvanizedGalvalumeAluminum-coated type 2Corrosion loss, micrometers15105GalvanizedGalvalumeCorrosion loss, micrometers15105GalvanizedGalvalumeAluminum-coated type 2Aluminum-coated type 200 2 4 6 8 10 12 14Exposure time, yearsFigure 2: Corrosion performance ofgalvanized, aluminium coated and Galvalumesheet in a severe marine atmosphere.00 2 4 6 8 10 12 14Exposure time, yearsFigure 3: Corrosion performance ofgalvanized, aluminium coated and Galvalumesheet in an industrial atmosphere.00 2 4 6 8 10 12 14Exposure time, yearsFigure 4: Corrosion performance ofgalvanized, aluminium coated and Galvalumesheet in rural atmosphere.10 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Continuous hot dip galvanized sheetingequivalent range for zinc is fromabout pH 5.5 up to pH 12.5.The 55% Al –Zn alloy provides goodperformance under paint, goodductility and reasonable edgeprotection although hot dipgalvanized sheet has been shown tohave still better edge protection,particularly on sheets more thanabout 1.5mm thick. Likewise, thegalvanized zinc coating has betterductility properties.Figures 2, 3 and 4 provide the resultsof long term atmospheric exposuretests on hot dip galvanizing,Galvalume (55% aluminium) and hotdip aluminium coated sheets. Thelatter aluminium coating is moreexpensive and it is not availablecommercially in RSA.The excellent performance ofGalvalume in the industrialatmosphere (SO 2 pollution) is clearindication of the ability of aluminiumto withstand corrosion attack down torelatively low pH levels.When extrapolating these exposuretest results with a view to reliablypredicting a maintenance free servicelife, it is important to take intoconsideration the original as appliedcoating thickness prior to exposure.Specifications for coated steel sheetdefine the required coating by massexpressed as the sum of the coatingon both sides of the sheet in gms/m2.This can lead to confusion,particularly if a less dense aluminiumcontaining coating is being evaluatedagainst a normal zinc coating. As areliable indication, the mean coatingthickness per side of the 55%aluminium coated sheet is 14µmcompared with 19µm per side of Z275galvanized material (137.5 gms / m2 =19µm).b) Zincalume Resin Coated Steel ®Unlike other types of steel roofsheeting, this can be easily preparedand coated during or immediatelyafter installation. Corrosion “duplextheory” states that the combined lifeof a zinc containing coating plus amatched organic coating appliedearly in the life cycle of the sheeting,will be considerably longer than thesum of the lives of the two productswhen used separately.Therefore the best protection andhence, life of this type of roofsheeting will be assured by applying asuitable coating early in the life of theroof. The type of organic coatingselected will vary depending on thecorrosive substances present in theatmosphere (e.g. marine or chlorideattack and industrial SO2 acid attack).c) GalfanGalfan is a 5% aluminium, ± 95%Zinc coating with a small amount ofmischmetal. In this particularapplication, mischmetal (a specialmix of various “rare earth metals”) isrequired to promote effectivebonding between the steel substrateand the metal coating. It hasbecome a standard product in manycountries for the wire industry and itis being processed in ever increasingquantities by the steel coil coatingindustry. Galfan is also successfullyused to coat steel tubing.This coating is more ductile than the55% aluminium alloy which is one ofthe reasons why it has been developedfor protecting wire. Cathodicprotection provided by Galfan is moreor less the same as that for galvanizing,while general resistance to corrosion issaid to be up to twice that obtainedfrom pure zinc. Galfan performsextremely well in coastal marineatmospheres but understandably the55% aluminium alloy is superior inindustrial environments.Tests undertaken in Belgium indicatethat the performance of Galfan inburied conditions is considerablybetter than that obtained from the55% aluminium coating. The Galfancoating is generally thicker due tothe presence of Zn/Fe alloys in thecoating structure.Meanwhile, the availability of Galfanin SA as a protective coating for steelsheet is distinctly limited at present.2) Continuously hot dip galvanizedsheetingThe coating applied by this processconsists almost entirely of pure zincwith a trace of aluminium (about0.02%) added to the zinc melt. Thecoating is ductile and providesexcellent cathodic protection atuncoated edges and surfaces wherecoating damage has occurred.Hot dip galvanized roof sheeting isavailable in a range of coatingclassifications, the most available ofwhich are three zinc coating grades.Z275 (137.5 gms/m 2 per side)mean coating thickness = 19µmZ450 (225 gms/m 2 per side)mean coating thickness = 32µmZ600 (300 gms/m 2 per side)mean coating thickness = 43µmThese are distinguished by the massof zinc present per square metre ofsheet surface.Since the life of a zinc coating ismore or less proportional to itsthickness in a given environment, itfollows that the Z600 zinc coatingwill provide more than twice themaintenance free life available fromthe Z275 coating. The long termatmospheric exposure tests depictedin figures 2, 3 and 4 demonstrateclearly that the 14µm thick 55%aluminium containing coating isattacked at a considerably lower ratethan the pure zinc coating, but thesubstantially thicker zinc film ofabout 43µm on Z600 galvanizedsheeting more than compensates forthis.The most commonly used galvanizedroof sheet coating is Z275 whichprovides extended corrosion controlin moderately corrosiveenvironments. When this coating isused in corrosive coastal marine orheavily polluted industrialapplications, duplex protection bymeans of an organic paint coating isrecommended. Painting should takeplace sooner rather than later inorder to avoid an accumulation ofVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 11

Continuous hot dip galvanized sheetingzinc corrosion products on the zincsurface which may be difficult toremove prior to painting. Foroptimum corrosion free life as wellas for aesthetically pleasingarchitectural purposes, duplexcoating is also recommended inenvironments where moderatelycorrosive conditions pertain.3) Duplex coil coated sheetingnew projects. In the case of existingstructures where maintenance isrequired, recommendations can beprovided by ARTF concerning themost cost effective methods ofrefurbishment or repair.Authors: Walter Barnett (Founder,HDGASA) and Rick Norwood (Founder,ARTF).Grateful acknowledgements toRon E. Cromarty (Chief Science Officer,Boutek CSIR, retired) and Martin S. Smit(Chief research officer (recently retired),Division of Construction and BuildingTechnology, CSIR,) for valuable assistance.Acknowledgement to Frank Porter’s ZincHandbook for the corrosion performancegraphs.Factory applied (usually silicon/polyester/urethane) colouredcoatings can extend the life andimprove the appearance of profiledsheeting considerably.This type of product has beenmanufactured in South Africa formany years by Mittal Steel(Chromadek) and HH Robertson(Colomet). Improved versions arecurrently being offered in technicalpublications and periodicals.Coil coated sheeting is an excellentchoice for vertical cladding of abuilding and other high visibilityareas. If correctly installed, it willprovide excellent durability bothinland and in coastal marineenvironments, other than in theaggressively corrosive zone which,depending on land contours andprevailing wind direction, is more orless within 1 kilometre of the surfline.BHP Steel Australia supplies a coilcoatedversion of Zincalume ResinCoated Steel Sheet ® called“Colorbond”. This is an excellentproduct, but unfortunately it is notreadily available in Southern Africa.Where significant weathering of thetopcoat has occurred, the coil coatedsheeting should be recoated by acoating specialist well experiencedwith this type of material. 8 to 12years after installation is the usualrecommended recoating interval.Each protective coating system hasits strengths and weaknesses. AnARTF approved consultant isavailable to provide technicalassistance at the design stage forDurability of hot dipgalvanized sheetingexposed to generalatmospheric conditionsThere is no doubt that in order to optimise the service life of thesheeting on a building in any environment, a factory paintedgalvanized steel sheeting system such as “Chromadek” or equivalent ispreferred. Alternatively, the zinc coating on the sheeting could be overcoated with a suitable paint system preferably shortly after thebuilding is erected. The latter alternative requires a comprehensivecoating and application specification and the services of a skilledapplicator to successfully apply the paint.Duplex coating technology suggests that the combined life of the zinccoating and the paint coating can be multiplied by a factor of between1.5 and 2.7, depending on the conditions at hand.However, an elaborate duplex coating system is only necessary if theservice life required by the sheeting is indeterminable and theadditional costs are considered negligible.If on the other hand, the required service life is determinable such thatthe overall life of the sheeting is required to be say 15 to 20 years in aC1 to C3 environment, making use of a Z275 class of coating, would beappropriate. Z275 has a nominal coating thickness of about 20µm.Similarly, if a 35 to 40 year service life in a C1 to C3 environment (seemap on page 7) is required, a Z600 class of coating would beappropriate. Z600 has a nominal coating thickness of 43µm.Making use of inappropriately coated roof fixing screws or a possiblefuture variance in the local micro-climatic conditions over theprescribed life of the sheeted project, can negatively influence thecorrosion rate and hence shorten the overall service life of thesheeting.12 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

ADVERTORIALSHAPING THE FUTURE OF STEELHot dip galvanized sheet for the light steel frame building industryDue to the rapidly growing demand for galvanized sheet, Mittal SteelSA has recently commissioned a new state-of-the-art 100 000t/yearhot dip galvanizing line to supplement its production capacity. Thisequates to approximately 26 million m 2 /year of 0.5mm thick sheet.The introduction of the new line increases Mittal SA’s galvanizingcapacity by 20% to 600 000t/year and has been designed toproduce galvanized sheet mainly for the roofing market with a steelthickness varying between 0.30 - 0.50mm, width between 762 - 1050mm and Zinc coatings between 90 and 160g/m 2 . (Although therequirement for light steel frame building industry is 275g/m 2 , it isanticipated that the new line will alleviate the current shortage ofroof sheeting)The increased tonnage from the new line will also relieve the pressureon Mittal’s other two galvanizing lines at Vanderbijlpark and enablethese lines to produce material for other applications.Apart from complying to the SANS Standard for galvanized sheet,Mittal SA also has the SABS Mark on its product, which serves tocertify its quality.The following branding Mittal Steel mark, appears at regular centresalongside the edge of all sheeting produced by the company, thebranding highlighted below is for a 925mm wide, 0,5mm thick, with aZ275 class of coating.Mittal Steel CID : P77148 W: 925 T: 0.50 C: Z275Galvanized steel sheet has a wide range of applications, includingroofing and cladding, security fencing, hot water geysers, expandedmetal manufacture, electrical switch boxes and ventilation ducting.Cold formed sections for Light Steel Frame Building (LSFB) systemshas recently been added to the long list of end-uses of galvanizedsheet in South Africa. These sections are produced on specialisedprofiling lines to narrow dimensional tolerances. During profiling thesections are swaged to facilitate connections, holes are punched forfasteners and the sections are cut to exact length required for eachindividual application. The profiling lines also have the facility to markeach section uniquely, to ensure it is used in the correct position.These sections are factory assembled into wall panels, roof trusses oropen web joists. The assemblies are subsequently despatched to sitefor rapid erection.Light Steel Frame Building has been in use elsewhere in the world forthe past 30 years. Recent developments in design software, which islinked to the profiling equipment, has created huge new interest in thisbuilding method. In order to develop this market in South Africa, MittalSteel was instrumental in establishing the Southern African Light SteelFrame Building Association (SASFA, a division of the SA Institute ofSteel Construction). Other founder members include Everite, BPBGypsum, Lafarge Gypsum, Owens Corning and Brits Nonwoven.For more information on Light Steel Frame Building or SASFA visitwww.sasfa.co.zaSASFA’s mission is to develop the light steel frame building industry inSouthern Africa. The aim is to capture 10% of the low rise building marketwithin 5 years. This implies that some 2 million m 2 (floor area) of buildingswill annually be constructed using LSFB systems. When this goal isreached, a sustainable new market for galvanized sheet of some 30000t/yr (1 850 tons of zinc/yr) will have been established. There arealready 12 of these profiling lines in South Africa, with sufficient capacityto provide light steel frames for 850 000m 2 of building per year.Mittal Steel South AfricaColin Thomas Tel: +27 (83) 304 0559Peter van Wyk Tel: +27 (83) 304 0430Website: www.mittalsteelsa.com

Continuous hot dip galvanized sheetingMajor new player in lightweight steelframe building industryWith lightweight steel frameconstruction on the increase world-wide,SA will be following suit with theestablishment of another major player –Vela Steel Building Systems (Vela SBS).“The construction industry is continuallyevolving. Technology is the driving forceand traditional building methods are nolonger the only answer. Lightweightsteel framing is the next step in theevolution of constructionmethodologies,” says Brent Harris,managing director of Vela SBS.Harris says that the technology oflightweight steel frame building has thepotential to make a palpable differenceto the delivery of houses in South Africa.“Construction times are significantlyreduced and the vastly improvedthermal insulation of the structureinsures not only a better quality endproduct but also one that offers bettervalue for the money invested,” he says.“It’s a double-whammy. The investmentvalue increases right at the beginning ofthe process because of the speed oferection and in the long-term, theimproved energy efficiency and reducedneed for maintenance render thebenefits of lightweight steelconstruction incomparable to traditionalbuilding methods.”Lightweight steel frame buildingconsists of structural wall frames androof trusses manufactured from coldformedthin gauge galvanized steelsections.Unlike other building processes, the wallpanels and roof trusses are erected first,allowing the roof tiling or sheeting to beundertaken before the wall claddingbegins, thereby giving the builders aroof to work under. This significantlyaccelerates the building process.The roof trusses are lightweight and canbe assembled on site, thereby negatingNewly constructed light steel frame single story building clad with brickwork.transport costs. Added benefits are thatthe steel is not affected by moisture, willnot warp or rot and is not affected bytermites, eliminating a number offactors to be considered when using amore conventional building materials.Vela SBS will be selling these trusses asa stand-alone item into the generalmarket.Exterior cladding can consist of a singleskin brick wall or fibre cement boardwhich is fixed to the wall frames.Services like electricity and plumbingare installed in the wall cavity created bythe frames.There are a number of different optionsfor cladding the internal walls. Theoption commonly used throughout therest of the worldis to pack high density insulation intothe wall cavity and clad them withgypsum board, then rhinolite and paintwhich offers an attractive finish forinternal walls and ceilings. Anotheroption is to shutter the walls and fill thecavity with lightweight concrete, and14 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Continuous hot dip galvanized sheetingthen plaster to achieve a similar effectto conventionally plastered brick walls.There are several advantages to Vela’slight steel frame building compared withconventional building in terms ofquality, cost, durability and speed.These include:◆◆Frames are assembled undercontrolled factory conditions.In the case of poor foundationconditions, steel framed buildingscan accommodate significantmovement without cracking.◆◆The steel frame dictates a highdegree of accuracy of buildingdimensions, with the result thateverything fits as planned.Walls are straight and true. Poorworkmanship is no longer an optionor excuse.◆ Time saving can be as much as 30%when compared with conventionalbuilding.Double story light steel frame building during construction.and complies with the Draft Code ofPractice for Lightweight Steel FramedBuilding Systems, developed by theSouthern Africa Light Steel FrameBuilding Association (SASFA). Eachstructure is signed off by a structuralengineer.“Our machinery is state of the art andour people have been trained to acompetency that is on a par withanywhere we have been. We lookforward to revolutionizing theconstruction industry in this country,”Harris concluded.◆◆◆Structures are lightweight. A steelframed wall, clad with fibre-cementor plaster board, offers a masssaving of 90% compared with adouble-skin brick wall.An estimated extra 4% floor space isobtained due to reduced thicknessof external walls when clad withfibre-cement board.Services are installed in the wallcavities without the necessity forchasing the walls.“All these advantages combine toreduce wastage, lower logistical costsand reduce time of construction. Sowhile the materials themselves maynot be less expensive than brick andmortar, there are savings to be made inthe construction process, energysavings because of improvedinsulation and the quality of the entirestructure ends up significantly betterthan a conventional one,” says Harris.Harris says his company hasbenchmarked the best productionpractice from around the world andthat the market here can expect thehighest possible quality from theoutset. Vela SBS has NHBRC approvalVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 15

Continuous hot dip galvanized sheetingThe fastenersrequired forlight weightsteel framedbuildingsWhen compared to the corrosionprotection or class of coatingspecified for roof, wall andlightweight frame buildings,ensure that the fasteners usedare similarly protected!To compliment the fixing of roof and wallcladding materials, while taking intoaccount the expected life of the structureand the environmental conditions onhand, the specified coating on thefastener is extremely important.South African Bureau of Standards isfinalising a specification SANS 1273 –Fasteners for roof and wall coverings inthe form of sheeting. This specificationcovers the material / coating, dimensionaland mechanical strength requirements fora number of fasteners and washers thatare used in the building industry for thefixing of roof and wall coverings in theform of sheeting.The specification will relate the expectedperformance of the coating / material tothe various corrosion categories in termsof ISO 9223, so that the specifier canselect the fastener coating/material tosuit the specified life of the sheeting /structure taking cognizance of thecorrosion conditions at hand.We look forward to the publication anduse of this specification by specifiers,involved in the selection of roof, side andend cladding fixing fasteners that canprovide similar corrosion protection tothe coating type and thickness of thespecified sheeting.Editor’s comment:We would recommend that the specification alsoincludes the fasteners used in lightweight steelframe buildings.HARRYRUPNARAIN1922 – 2006Beloved friend and greatlyrespected businessman, HarryRupnarain (1922-2006) sadlypassed away on 28 December2006 at his home in La Lucia,Durban.Having established numerousesteemed and successful businesses including New Age & Excel Stationeryand most recently, Harrismith Galvanising and Steel Profiles, Mr Rupnarainwas constantly held in high regard amongst his peers. His business etiquettewas always gracious, sincere and honourable. He was a pillar of thereligious community, but first and foremost Mr Rupnarain was a dedicatedfamily man. A loving father, a doting grandfather and an adoring greatgrandfather,he is survived by a family that will miss him immensely.ERIC KINGREMEMBERED30/12/1949 –23/01/2007ObituariesEric Basil King was born on 30December 1949. This Durbanitestarted his career at FergussonPaints, working as ProductionSupervisor, Laboratory QC andTechnical Representative. Ericwas also employed by DekroPaints as Technical Representative, providing technical service to the MarineDivision. His Duplex Coating expertise, lead him to secure the position ofContracts Manager for Millburg Painting Contractors where he supervisedand managed contracts. In 1991 Eric joined Voigt & Willecke Galvanizing asSales Representative - he was promoted to Production Manager in 1996. Ericstarted his own Sand-Blasting & Duplex Coating business in 2006.Eric will be remembered for his keen sense of humour and ready smile. Hisexpertise & contribution to both the Hot Dip Galvanizing and Duplex CoatingIndustries will be deeply missed. He is survived by his wife Jeanie, daughterJessica & his parents.16 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Safety and security including continuous galvanizing of wireAndrew Mentis plays it safe atMarion IslandMore than 1 000m 2 of Mentis PositiveNon-Slip Grating, developed byAndrew Mentis to give exceptionalnon-slip characteristics, was used onthe R200-million Marion Islandweather station. This award winningproject clinched a trophy in the 2006Eskom Hot Dip Galvanizing Awardsevening.With treacherous underfoot conditionsdue to the sub-Antarctic climate, theMentis grating was used to provide asafe and viable alternative route forpedestrians as well as forklifts. Thehazardous underfoot conditions madeit virtually impossible for personneland delivery staff to traverse thedistance between the harbour and thestation buildings and its surroundingswithout practically sinking up to theirhips in the muddy terrain. It is for thisreason that the weather station andwalkways were constructed onessentially thousands of piles rammedinto the muddy ground.Mentis Positive Non-Slip Hot Dip Galvanized Grating was used on all the walkway areas betweenthe harbour and the station.Andrew Mentis, a leading localmanufacturer of grating andexpanded-metal products, suppliedits Positive Non-Slip Grating upon therecommendation of fabricator PetrelEngineering. Michael Franzen,managing director of PetrelEngineering, says the fabricator hasan extensive track record in Antarcticresearch stations, including theSANAE base, and has subsequentlyestablished a successful and longlastingrelationship with AndrewMentis.“In addition to being able to offer theideal grating product for such anarduous environment, where thesafety of personnel is paramount,Andrew Mentis also offers the bestservice, delivery times and costing,”Andrew Mentis Positive Non-Slip Hot Dip Galvanized Grating is the solution for the Weather BaseStation on Marion Island.Franzen says. “This makes for an idealholistic solution for such specialisedprojects as the Marion Island weatherstation.”One of the few weather stations in thesouthern Indian Ocean, Marion Islandplays a critical role in providinginformation about weather systemsover oceans surrounding South Africa.A cold, wet and windy climate,together with boggy terrain andmainly mosses and ferns forvegetation, makes for a hazardousterrain that necessitated theprotection of both personnel andequipment.Ted Jarvis, managing director ofAndrew Mentis, explains that the18 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Safety and security including continuous galvanizing of wireexceptional non-slip characteristics ofMentis Positive Non-Slip Grating wererealised by means of the positiveraised sections forming multidirectionalobstructions on the top ofeach bearer bar. The major advantageof this product is that the non-slipfeatures do not compromise its loadbearingcapacity, as is the case withserrated grating.“The positive profile also means thatthis grating is self-cleaning,eliminating the dirt build-upcommonly associated with serratedgrating. The Mentis Positive Non-SlipGrating uses a pressure lockingsystem to secure the bearer andtransverse bars, rendering it extremelysolid and safe for all applications.is its use as a barrier insidewarehouses to protect walls andmachinery from materials-handlingequipment such as forklifts. The 2.6-mm-thick Mentrail guardrail, suppliedin standard lengths, is available ineither uncoated or hot dip galvanized,and with a ‘buried’ end for thebeginning and an end wing for thetermination of each section.Established in 1950, Andrew Mentis’sproducts are used extensively in agamut of industries, from powergeneration and mining to thepetrochemical, motor, construction,food and beverage, pulp and paperand steel sectors. It has its head officein Johannesburg, with a nationalnetwork of sales offices.More about Andrew Mentis(Pty) LtdAndrew Mentis (Pty) Ltd is a leadingmanufacturer of grating, expandedmetal, Mentrail (guard-rails for roads),DieLine Walkways, industrial handrailsystems, steel floor tiles and Mendrill(automatic drilling and boringmachines). Established in 1950, thecompany’s products are used inindustries as diverse as powergeneration, mining, petrochemical,motor, construction, food, paper andsteel.The company operates from its headoffice in Johannesburg, with anationwide network of offices.In addition, the non-slip features workequally well in all directions, in allfinishes, and on both leather- andrubber-soled footwear. “This makes fora highly flexible product adaptable toa range of arduous applications, ofwhich the Marion Island weatherstation is a sterling example,” Jarvissays.Due to the remote location of theproject site, combined with thelogistical difficulties of obtainingsuitable construction materials andequipment, designer and structuralengineer Endecon Structural(Centurion) opted for pre-fabricated3CR12 and hot dip galvanized steel forthe actual weather station itself. Thelocation also required specialattention to corrosion protection, forwhich hot dip galvanizing is an idealsolution. “Our expanded-metalproducts are also an ideal solution tosecure premises against intruders, orto ensure the security of plant and thesafety of personnel,” Jarvis comments.Apart from its expanded-metalproducts, Andrew Mentis is also wellknownin the mining and roadbuildingsectors for its Mentrailguardrail for both roads andhighways. Another novel applicationVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 19

Safety and security including continuous galvanizing of wireVan Ryssen Dam, PhalaborwaProblemIn order to comply with the NationalWater Act (Act 36 of 1998), FoskorMine wanted to collect and containpolluted surface run-off from itstailing dams in the Van Ryssen Damfor re-use in the mines processingplant.The Water Management Projectincorporating this recycling will resultin reduced raw water requirements,currently sourced from this water scarearea at a barrage in the Olifants River.The dam was sealed with animpermeable Bentonite layer anddesigned to cater for the 1:50 year floodproviding further benefits to theenvironment by preventingcontamination of the downstreamwater resource.SolutionAs with all earth embankments, thehigher the structure, the more fillmaterial is required. The initial designsolution comprised a 22m high rockfilldam with an upstream earthfill facingonly.Starting Terramesh TM installation.Packing the front face.However, through a simple adjustmentinvolving reducing the height of therockfill structure to 19m and making upthe last 2.4m in height with a verticalTerramesh wall manufactured fromcontinuous hot dip galvanized wire toSANS 675, on the upstream side, theamount of required rock wassignificantly reduced. Lack of suitabledam-building material e.g. clay, meantthat recycling of the waste rock dumpsto create a rockfill dam was the mostobvious solution.Starting the continuous hot dip galvanized wireTerramesh TM installation.Packing the front face.BenefitsThe greatest benefit lay in thereduced earth fill quantities andproject costs as tabled below:Original Saving % SavingEarthfill (m 3 ) 290 000 100 000 30Cost (R million) 32 8 25Maccaferri/African Gabions’ MacStars2000 software program was usedto design the structure. The programperforms a series of stability checksof the reinforced structure andprovides a detailed calculationreport, cross sections and safetyfactors for the final design.Typical section through a dam wall.Seismic loading together with theRMF flood had to be accounted forduring the design of the wall.20 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Safety and security including continuous galvanizing of wireFocus on securityYou’re enjoying a quiet evening at home withyour family and the unthinkable happens.Something you have read about so manytimes but hoped and prayed would neverhappen to you. The unmistakable sounds ofan intruder, already inside the house.Your mind freezes for an instant. Once youstart to think again, you madly run throughall the options – do I try to get to my firearm,or the nearest panic button or do we try toescape into the garden and hope that there arenot more of them outside waiting to come in?These are some vital questions, sowhere do we start? How about theold adage of prevention being betterthan a cure?Having been in the security industryfor over twenty years, Provicom havein this time explored, tried andtested many options. They have nowdeveloped a system of perimeterprotection which they feel to be themost practical, reliable andaesthetically pleasing withinaffordable parameters.The Rolls Royce® of all securitysystems in Provicom’s DivisionalManager, Geoff Brandt’s opinion isPerimeter Power Protection. This isthe point where one controls allpotential intruders, keeping them outwith a solid barrier that cannot beclimbed over or burrowed under. Thebarrier will also provide one with awarning as the intruder attempts togain access to one’s property and willact as a deterrent to keep mostperpetrators from any furtherattempts. A warning at this stage willalso take away the element of surpriseand forewarn one. Perimeterprotection means that one is in fullcontrol of one’s space at all times.Here is how our Perimeter PowerProtection Plan works.Provicom’s Perimeter PowerProtection PlanOuter BarrierSteel palisade fencing designed toeach unique application.• Designed to unique aestheticaltastes.• Designed to outsmart even thesmartest vandal.• Designed to last using the bestpossible materials for theapplication.Volume 4 Issue 1 2007 Hot Dip Galvanizing Today 21

Safety and security including continuous galvanizing of wire• HOT DIP GALVANIZED fordurability (including the smallestfastener, used to connect theerected pallisade fence).• Access to be controlled remotelyat this boundary.Inner BarrierElectrified security fence designed toeach unique application• This is the beginning of theintelligent defense line• This is visually the strongest andsafest deterrent.• This also acts as the first earlywarning.• This is aesthetically designed inconjunction with the palisadefence.• It signifies a no go area.• Where spatially available wideanti-burrow systems are installed.This is done at a fraction of thecost of concrete or steel plinths.• This helps enforce access controlmeasures.• HOT DIP GALVANIZED fordurability (including the selfdrilling screws required to fix theelectrical wiring system).• Zoning, narrows target areagiving you the element ofsurprise.Visual BarrierThe interfacing of cameras withintelligent electric fence systems.• Visual identification.• 99% accurate intruder alarm,using the leading partner inaccess control systems.• Can identify perpetrator even ifyou are not present.• Acts as your eyes, and ears whenyou are not available.• Camera mountings speciallymanufactured.• HOT DIP GALVANIZED fordurability (including the selfdrilling screws required to fix thevisual barrier equipment).Wire galvanizingspecifications revised!Hot dip galvanized fencing wire is produced from mild, high tensile orvery high tensile steel wire, on a continuous coating line which includesannealing, acid cleaning, fluxing, galvanizing, wiping to remove excesszinc and recoiling of the finished wire. The process is similar inarrangement to the Sendzimir process used for continuous galvanizedsheeting. Between 20 and 40 individual wires are hot dip galvanizedsimultaneously by passing through a molten zinc bath held at 450 degreescelcius.Coating thickness is generally related to the diameter of the wire beingprocessed, as is recognised in the hot dip galvanized wire standards. Lifeof a hot dip galvanized coating is relative to the coating thickness andtherefore the thicker the coating the longer it will last in a givenenvironment.The two specifications that to date have covered wire galvanizing in SouthAfrica are SANS 675 and SANS 935. The former specification was amendedin 1993 to include only one class of coating for fencing products i.e. aheavy zinc coating and after a discussion at the SABS that in principle,international specifications be considered for adoption or inclusionwherever feasible, is currently under review with the intention of beingrevised to include aspects covered by EN 10223. SANS 675 is alsoreferenced in the gabion specification SANS 1580. SANS 935 whichincluded three classes of coating, has been withdrawn and replaced bySANS 10244 parts 1 and 2.FEATURES 2007MAY / JUNEArchitectural, agricultural and the world ofhot dip galvanizing around us, also incorporatingstadiums; staircases; furniture; wine industry; conveyancepiping; heat exchangers; rebar.AUGUST / SEPTEMBERThe Annual Awards Event; masts and poles; traffic signsand sign gantries; scaffolding.NOVEMBER / DECEMBERMining and quarries; gratings; overland conveyors;fasteners.22 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Miss ConceptionsMISCONCEPTIONSMiss Conception puts it “straight”“Miss Conception” rectifies incorrectimpressions concerning hot dip galvanizing.A hot dip galvanized coating can be successfully used attemperatures up to 419°C, which is the melting point of zinc.True or false?Hot dip galvanizing is formed by way of a metallurgicalreaction between molten zinc, at 450ºC, and steel “iron”.Reaction between zinc and steel can occur at zinc temperatureswell below the melting point of zinc, i.e. when both the steeland the zinc are in the solid state.The cunning use of a specially profiled guard rail sectionto house a camera to record speeding motorists may inthe future be on the cards?The best example of this is the well-known sherardizingprocess, which was developed by a Mr. Sherard of the UnitedKingdom many decades ago. In this process, steel articles aredeposited into a barrel containing a mixture of zinc dust andsand and then tumbled in a rotating barrel at a temperature ofabout 380°C (well below the zinc melting point of about419°C). In this way a coating consistency of iron / zinc alloy isformed by diffusion despite the fact that both metals are in thesolid state.In the case of hot dip galvanizing, the coating is made up of arelatively pure outer zinc layer which overcoats a series of iron /zinc alloy layers similar in some respects to the alloy achievedby the sherardizing process.If a hot dip galvanized coating is heated up to a temperature atwhich diffusion between zinc and iron takes place (about250°C) a portion of the zinc layer of the coating combines withiron to form further iron / zinc alloy. Because both metals arein the solid state a void is thus formed between the remainingouter zinc and the underlying alloys. This leads to aphenomenon described as heat peeling, where the remainingouter zinc layer of the coating separates from the underlying Fe/ Zn layers and flakes off.Heat peeling does not remove the entire coating since thealloy structure of the coating remains intact. The overallcoating thickness is, however, significantly reduced.For long-term service life, a hot dip galvanized coating shouldnot be exposed to temperatures in excess of 200°C for anylength of time. Occasional temperature hikes of up to 350°Ccan however be tolerated.CAPE GATE(PTY) LTDTel: 016 980 2121 Web: www.capegate.co.za Fax: 016 988 3421Cape Gate is a fully integrated producer ofsteel, wire and wire products with our ownsource of raw materials.All our products meet recognisedinternational standards and are sold worldwide in a secured and well establishedgrowing customer base.We serve....● Mining● Agriculture● Industry● Commerce● Civil engineering and construction● Domestic and foreignmarketsVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 23

Duplex CoatingsA life cycle costing analysis comparingpainted steel, hot dip galvanizing andduplex coating systemsThe economics of hot dipgalvanizing, including duplexcoatings (hot dip galvanizing + asuitable series of top paint coatingsover galvanizing) versus a goodspecification paint coating systemfor corrosion control of carbon steel,is the subject of much debate.The economics of any corrosioncontrol (protection) system cannotand should not be based on initialcosts, but rather on the life cyclecosts of the protective coating. Lifecycle costings can become extremelycomplicated being dependent onnumerous variables that theanalysist wishes to include in thecalculation.Classification Description Corrosion rate Corrosion rateof Steel of Zinc(µm/yr) (µm/yr)C1 Interior: Dry benign environment. ≤1.3 ≤0.1C2C3C4C5Interior: Occasional condensation.Exterior: Urban inland or mild >1.3 to 25 0.1 to 0.5Interior: High humidity, some air pollution.Exterior: Urban inland or mild coastal >25 to 50 0.5 to 2Interior: Swimming pools, chemicalplants, etc.Exterior: Industrial inland or urban coastal. >50 to 80 2 to 4Exterior: Industrial with high humidity orhigh salinity coastal. >80 to 200 4 to 8Table 3: Atmospheric corrosive environments classified in terms of ISO 9223, similar to ISO 12944,see table 4 for paint.The first five photos show the early failure of a multi-coat paint coating system used to protect the steel components of a well known PE sportsstadium where little regard was taken of the life cycle cost of the coating system and costly refurbishment of the coating was required after a shortperiod of twelve years. Photo below right shows the frames of the seats on the same stadium that were originally hot dip galvanized and at the timethese photos were taken, still had a coating thickeness of in excess of 60µm. (60µm of hot dip galvanized coating on these seat frames representsalmost what was originally required in terms of the specification at the time the stadium was built).24 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Duplex CoatingsThe following life cycle costinganalysis has been simplified bylimiting such variables toidentifiable, accepted and publishedvariables. Corrosion control systemsand life cycle performance is afunction of the environment in whichthe specific corrosion control systemis required to serve. For purposes ofthis specific life cycle costinganalysis the following criteria hasbeen used.Environmental and corrosionratesTable 3 (ISO 9223) defines thecorrosion rates of steel and zinc.From this data one can estimate theapproximate length of time toperforate a given thickness of steel,and more specifically the service lifeof a given thickness of a hot dipgalvanized (zinc) coating.Classification Corrosivity Exterior InteriorC1 Very low Inside heated buildingwith natural atmospheres,offices, shops, schools, hotels.C2 Low Atmospheres with low pollution Unheated buildings whereand dry climate. Mostly condensation may occur.rural areas.Depots, sports halls.C3 Medium Urban and industrial Production rooms with highatmospheres, moderate sulphur humidity and some air pollution.dioxide pollution. Moderate Food processing plants,coastal climate. laundries, breweries, dairies.C4 High Industry and coastal areas. Chemical processing plants,swimming pools, boat yardsover sea water.C5 - I Very high Industry with high humidityIndustry and aggressive atmospheres.C5 - M Very high Marine coastal, offshore,Marinehigh salinity.Table 4: ISO 12944 – Classification of environments.CBT (011) 868-3408 DC1022/10/05Specialists in the preparation and painting of hotdip galvanized steel, sweep blasting, abrasiveblasting, tank linings and industrial paintingContact Mike BookTel.: (011) 827-4221 • Fax: (011) 827-4561Cell: 072 782 8853 • Email: bulldogproj@murrob.comP.O. Box 82741 Southdale 2135Genrec Office Park, Cnr Dekema & Nieman Rd,WadevilleSave the surface... and you save allVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 25

Duplex CoatingsHot dip galvanized as per 6mm 8mm Min. Coating Mean CoatingSANS121 (ISO1461) Thickness (µm) Thickness (µm)Surface area (both sides) 42 m 2 /ton 32m 2 /tonPrice per square metre R66-67 per m 2 R87-50 per m 2 75 85Table 5: Approximate pricing of hot dip galvanizing.HDG + 3 coat Description Price/m 2 Price/m 2 Min. Coating Mean Coatingtop paint 6mm 8mm Thickness (µm) Thickness (µm)Primer HDG to SANS121 R66-67 per m 2 R87-50 per m 2 75 85(ISO 1461)Preparation for Sweep blast with R20-00 R20-00paint non-metallic grit< 3 bar pressureInitial High build epoxy R30-00 R30-00 75 110CoatFinishing Top Polyurethane colour R27-00 R27-00 40 50CoatTotals Duplex Pricing R143-67 R164-50 190 245Table 6: Approximate Pricing of a Duplex Coating System.Three-Coat Paint Description Price/m 2 Minimum (DFT) Mean (DFT)System Coating Coating(All gauges) Thickness (µm) Thickness (µm)Preparation Abrasive blast to Included in theSa2 1 /2primer pricePrimer Inorganic zinc rich with R70-00/m 2 50 75min. 81% zinc contentIntermediate Coat High build epoxy R30/m 2 75 110Finishing Top Coat Polyurethane colour R27-00/m 2 40 50Totals R127-00/m 2 175 235Table 7: Approximate pricing of a three-coat paint system.Coating System C2 C3 C4Hot Dip Galvanizing 170+ 42 to 170 21 to 42(85μm)Duplex Coating Not required for Not required for 46 to 78corrosion control corrosion control3 x Paint system 12 to 15 10 to 12 10Table 8: Life cycle of the three systems (years to 5% rust or life to 1st maintenance).Net Rate per year of life to 1st maintenanceCoating System Prices/m 2 C2 C3 C4Hot Dip R87-50 R87-50/170yrs R87-50/42yrs R87-50/21yrsGalvanizing R0-52 R2-08 R4-17(85μm)Duplex Coating R164-50 Not required Not required R164-50/46yrsR3-583 x Paint system R127-00 R127-00/12yrs R127-00/10yrs R127-00/10R10-58 R12-70 R12-70Table 9: Life cycle costs, based on life to 1st maintenance.Scope of the costing analysisThe example will compare the lifecycle costs of hot dip galvanizing,duplex coatings (hot dip galvanizingplus a suitable top paint system) anda three-coat paint system in a C4environment as defined in ISO 9223and ISO 12944.Costings and specifications asat September 2006Hot dip galvanizing costs, based onthe current zinc price of R25 000 perton, will approximate to a selling pricebetween R2 700 per ton to R3 100 perton, depending on steel thickness. Inorder to simplify the calculation,R2 800 per ton of medium to heavygauge steel has been used. (6 and8mm thick steel plate). Converting thisprice per ton to a price per squaremetre of surface we have the followingas shown in tables 5, 6 and 7.Kindly note that the prices quoted donot in any way represent the actualprices given by member galvanizers,but are estimates used for thepurposes of costing analysis. Thehigher, and more conservative, pricefor hot dip galvanizing has been usedin the calculations. Estimated costs ofthe paint system, were obtained froma reputable painting contractor.Service life or life cycle costs ofthe three defined systemsFrom ISO 9223 (table 3), threeenvironments have been selected, ie.C2, C3 and C4 for purposes of the lifecycle costing analysis. These threeenvironments are described in tables 3& 4. We will use 8mm steel for thepricing of hot dip galvanizing.Should one wish to now estimate thefigures for a C5 environment, wewould have the followingapproximations:C5 – Exterior: Industrial with highhumidity or high salinity coastalHot dip galvanizing on its own wouldlast between 10 to 21 years, with a26 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Duplex Coatingsnet cost per year to 1st maintenanceof between R4-17 to R8-75, i.e. R87-50/(10 to 21yrs).Duplex would extend the life cycle tobetween 30 to 46 years with acorresponding life cycle cost of R3-58 to R5-48 per year, i.e. R164-50/(30to 46yrs).A three-coat paint system isestimated to last 10 years, with acorresponding life cycle cost of R12-70 per year, i.e. R127-00/10yrs.The above figures are conservativeand do not account for future valuesor the cost of 1st maintenance, suchas escalation and plant downtimecosts (i.e. lost production duringshutdowns), scaffolding, cleaningand recoating a structure as built.ConclusionA thee-coat paint system is 255%more expensive than the DuplexSystem – System in a C4Environment calculated as follows:(Paint System R12-70) – (Duplex System R3.58) x 100%Duplex System R 3.58Paint System = 255% more expensivethan Duplex systemAs a footnote, a quality DuplexSystem should include input of theAsset owner, Hot Dip GalvanizersAssociation, Paint Manufacturer andthe Applicator at the design stage ofthe project.ConclusionProject engineers, property ownersand developers should seriouslyconsider life cycle costs and notbase values and project decisions onthe initial costs only. Balanceddesign to meet environmentalconditions is essential in thedetermination of the corrosioncontrol system that is selected for agiven project.The Association would like to acknowledge the advertisersand thank them for their supportAndrew Mentis .......................................................................................................... page 19Babcock Ntuthuko Powerlines ................................................................................ page 17Cape Gate (Pty) Ltd.................................................................................................. page 23Chemplus .................................................................................................................. page 27Chemserve Orlik Systems ........................................................................................ page 21CWI............................................................................................................................ page 21Duplex Coatings cc .................................................................................................. page 25Galvrite Galvanising (Pty) Ltd.................................................................................. page 33Hi-Tech Elements........................................................................................................ page 41Highveld Steel & Vanadium Corp........................................................................... page 3Lianru Galvanisers (Pty) Ltd...................................................................................... page 15Metsep SA (Pty) Ltd .................................................................................................. page 31Mittal Steel South Africa .......................................................................................... page 13Phoenix Galvanizing ................................................................................................ page 39Plascon ...................................................................................................................... page 9Robor Galvanizers ..........................................................................................Inside Front CoverRoof Technology Services........................................................................................ page 6Supergalv (Pty) Ltd.................................................................................................... page 5Surface Treatment Technologies (Pty) Ltd .............................................................. page 5Zincor ........................................................................................................................ page 37CHEMLEADERS IN SURFACE CHEMISTRYThe leaders inprocess bath controlto the galvanizingindustryCONTACT US:PLUSGAUTENG HEAD OFFICE:Tel: +2711 760 6000 Fax: +2711 760 6070Website: www.chemplus.co.zaBob WilmotVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 27

Duplex Coating ReportDuplex coated verandah columns atParklands Shopping Centre – Cape TownAs part of the Association’s effort toeducate and improve the frequentineffective communication between theend client and the galvanizer, often viaa number of contracting parties, thespecifiers finish expectations and themanufacturer and galvanizer’scommitment to the quality of the finalproduct, etc. we include for yourreading, this coating report by theAssociation.For obvious reasons names of allparties have been withheld but thearticle might prove invaluable to othersin order to avoid similar situations infuture.Some protuberances and general coating roughness, normally acceptable when only hot dipgalvanizing is required, should be removed prior to painting – see HDGASA 03-2006.ReportThe Hot Dip Galvanizers Associationwas asked to comment on the duplexcoated tubular columns supporting theverandah section at ParklandsShopping Centre – Cape Town.Following a brief inspection of thecoatings, we report as follows:In most instances the primary reasonfor using hot dip galvanizing is toprotect steel for corrosion protection.For this reason two things areimportant with a hot dip galvanizedPhotos above show unacceptable coating roughness and a zinc run at the weld area, which shouldideally have been removed prior to painting.The general impression of the duplex coating looks impressive and provided the paint type and subsequent DFT of the paint coating is suitable, willprovide an extended service free life in this environment.28 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Duplex Coating Reportcoating and they are coating thicknessand coating continuity.Additional corrosion protection can beachieved by over coating a hot dipgalvanized coating with an appropriatepaint system, called a duplex system.Here besides coating thickness andcontinuity a further element must betaken into account and that is therelevant smoothness of the hot dipgalvanized coated surface foraesthetical appearance of thecomponent.For this reason it is often felt that inpreparing for subsequent painting overhot dip galvanizing, adequate surfacepreparation is mandatory for overallcoating success.Surface preparation can be achieved bymaking use of a chemical cleaner withvariable results or by sweep blastingthe hot dip galvanized surface by usinga micro-blast material and the correctblast pressure.Correctly done the latter surfacetreatment not only cleans the surfaceof contaminants but fluffs up the softzinc layer providing a surface key andremoving small surface imperfectionssuch as those seen at ParklandsShopping Centre. See photos left.Although the majority of thecomponents seemed to be acceptable,it would be appropriate that aspecification be issued at the time ofcontract to address these issues beforethe paint coating is applied.NOWWITH CPDPOINTSCoatingInspectors CourseHot dip galvanizing is one of the most widely used methods of protecting steelfrom corrosion. As a final step in the process, the hot dip galvanized coating isinspected for compliance with the appropriate specifications.This Coating Inspectors Course has been designed to provide delegates with sufficient knowledge to test,inspect and interpret test results.Following the course and successful result in a three-part exam, the delegate will be issued with a certificate, andif required, registered as an approved HDGASA inspector. Registration will be confirmed on an annual basis.Successful inspectors will become Individual members of the Association for the year.The course will be run from the Hot Dip Galvanizer’s Association Offices in St. Andrews, Bedfordview. Bookings arelimited (maximum 20 people) and will be treated on a first-come-first-serve basis.COURSE CONTENT◆ Introduction to corrosion ◆ Understanding zinc coatings◆ Inspection before hot dip galvanizing ◆ Inspection after hot dip galvanizing◆ Quality assurance in coating applications.COURSE DURATIONThis is a 2-Day Course comprising lectures on the first day, a Plant Tour in the morning of the second day, and thequalifying examination in the afternoon.DATE AND TIMECourses commence at 08h00 sharp and end at 16h30, on the following dates in 2007: March 6 & 7; May 8 & 9;July 10 & 11; September 4 & 5 and November 6 & 7.Lunch and refreshments will be provided. Comprehensive course notes can be collected from our offices two weeksbefore the course.COURSE COST AND PAYMENT TERMSR2 394.00 per person inclusive of VAT. Should you have 2 or more delegates from the same company, course costswill be R2 166.00 per person inclusive of VAT. Please note that payment is due on the first day of training. Chequesto be made payable to “Hot Dip Galvanizers Association SA”. Members qualify for a discount.SHOULD YOU BE INTERESTED, KINDLY CONTACT SASKIA SALVATORI ATTHE ASSOCIATION.NOTE: All professional Engineers, Technologists, Technicians and Certificated Engineers are required toachieve a certain number of points for Continuous Professional Development (CPD). By attending theAssociation's two day Coating Inspection Course, you will obtain 2 points (accredited by ECSA).The Association has a specification –HDGASA 03-2006, which was primarilydeveloped to address issues such asQuality control; Coating repairs; Qualitysurveillance; Handling and storage; Siterepairs and Duplex coatings.Following the above results we havesubsequently incorporated clauses toaddress the removal of protuberances,zinc lumps and runs, etc by thegalvanizer for subsequent duplexcoatings.Terry SmithVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 29

Coating ReportWet storage stain and subsequent redrust to the hot dip galvanizedsheeting on a slag crushing plantAs part of the Association’s effort to educateand impove communication between all, weinclude for your reading, this coating reportby the Association.For obvious reasons names of parties havebeen witheld but the article might beinvaluable to others in order to avoidsimilar situations in future.The Hot Dip Galvanizers Associationwas asked to comment on the wetstorage stain and subsequent redrusted areas to the roof, side andend sheeting of a slag crushingplant. We report as follows:ReportWet storage stain (white rust)Wet storage stain is the name given tothe white bulky deposit, which mayform on the surface of closely stackedfreshly galvanized articles, whichbecome damp (from exposure to rainor condensate) under poorly ventilatedconditions during storage or in transit.Although in extreme cases theprotective value of the coating may beimpaired, attack is often superficialdespite the relative bulkiness of thecorrosion product. Where surfacestaining is light and smooth withoutgrowth of the zinc oxide layer asjudged by lightly rubbing fingertipsacross the surface, the staining willgradually disappear and blend in withthe surrounding zinc surface as aresult of normal weathering in service.When the affected area will not befully exposed in service or when it willbe subjected to a humid environment,wet storage staining must beremoved, even if it is superficial. Thisis essential for the basic zinccarbonate film to form. The formationof this zinc carbonate film isnecessary to ensure long-term servicelife. In general terms light depositscan be removed by cleaning with astiff bristle (not wire) brush or scotchbrite pads and industrial vim. Heavierdeposits can be removed by brushingwith a 5% solution of sodium orpotassium dichromate with theaddition of 0.1% by volume ofconcentrated sulphuric acid.General view of the end sheeting.Alternatively, a 10% solution of aceticacid can be used. These solutions areapplied with a stiff brush and left forabout 30 seconds before thoroughlyrinsing and drying. Wet storage stainis not necessary a cause for rejection,provided that the specified minimumcoating thickness is present.Unless present prior to shipment fromthe sheeting manufacturer or stockist,the development of wet storage stainis not necessarily the responsibility ofthese two parties.General view.Close up of the side sheeting.The customer must exercise propercaution during transportation and30 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Coating ReportGeneral view of the roof sheeting showingdeposits of wet storage stain and subsequentred rust.Deposits of wet storage stain have beenremoved from the sheeting.Coating thickness readings have been takenand are still above the requirements for aZ275 class of coating.subsequent storage to protectagainst wet storage staining.Coating thicknessGenerally local specifications call forthe use of continuously galvanizedsheeting according to SANS 3575 /4998 coating grade Z275. Thisspecification requires a coating massof 275g/m 2 as a triple spot test but235g/m 2 on a single spot test. Thespecification also states that not lessthan 40% of the single spot test will befound on either surface. This equatesto a nominal zinc coating thickness ofabout 20µm with a minimum coatingthickness of 13.5µm.The equivalent thickness iscalculated from the followingformula:Thickness in microns (µm) =Mass per unit area, g/m 22 x 7(2 includes both sides and 7 is theapproximate specific gravity of zinc).Volume 4 Issue 1 2007 Hot Dip Galvanizing Today 31

Coating ReportRed discoloration has been removed.Coating thickness is just below the minimum prescribed in SANS 3575, which for Z275 is 13.5µm.While the coating thickness readingstaken on site by means of a calibratedelectro-magnetic thickness gauge weregenerally slightly higher than thatrequired in the specification, it isworthwhile to bear in mind thatreadings done in this manner may onlybe used as an approximation. Shouldaccuracy proving coating thickness forany reason be required, samples will benecessary for stripping purposes.Conclusion andrecommendationsSafe StorageLocation of coating Mean Min Max No of readingsthickness readingsGeneral 23 59 37 43White rust removed 32 21 43 31Red rust area 1 26 8.5 55 # 27Red rust area 2 33 10.1 69 # 31# – While every effort was taken during the coating inspection to remove all contaminants priorto measuring the residual coating thickness, sometimes contaminants remain, resulting in theimpression that the coating is thicker than specified.Coating thickness readings (µm).regularly to ensure that moisturedoes not penetrate the stock.To prevent unnecessary damage to hotdip galvanized or colour-coated sheets,proper measures should be taken toprevent contamination by moisturewhile the material is still bundled ornested in stacks.If not required for immediate use, coilsor packs of sheets must be stacked onsite under properly designed cover,clear off the ground and protected fromwind driven rain. Plastic tarpaulins,which completely envelop packs ofsheets or coils should not be used, as asudden drop in ambient temperaturemay cause condensation of watervapour, which can easily be drawn inbetween nested sheeting by capillaryaction.Ideally, deliveries of hot dipgalvanized and colour-coated steelsheet to the building site should bescheduled for a storage period of notlonger than two weeks prior toinstallation. Inspect the storage siteHowever, although the procedure ofsafe packaging of sheeting duringtransport and site storage is wellknown within the galvanizing industryand others, it would be appropriate ifthe sheeting supplier made this knownto customers such as this customer atthe time of delivery, so that effectiveprevention methods of wet storagestain could have been put in place.Coating repair:1. Rub red rusted and heavy whiterusted areas (including any areasunderside the sheeting on theinside of the building see photoright) with steel wire wool toremove all corrosion products.2. Remove all dust and debris.3. Clean compromised areas and ifrequired the entire sheeted surfacewith a water soluble degreaser andscotch brite pads.4. Thoroughly remove all residualThoroughly clean all heavily white rusted areason the undersides of the sheeting of thebuilding prior to any subsequent coating repair.chemicals with running water,obtain a “water break free surface”.5. Apply one coat of “Zincfix” (seeattached) to 100µm DFT to allcompromised areas and overlap thesurrounding unaffected coating byat least 20mm. Wait to dry.6. If required, apply one or two coatsof water based acrylic paint to aDFT per coat of 40µm or equal.Terry Smith32 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Walter’s CornerWalter’s CornerThe hot dip galvanizing industry is alive and wellDuring the past few months, therehas been an unprecedented increasein the demand for hot dipgalvanizing as a means of corrosioncontrol. This has resulted intemporary delays and inconveniencefor end users as the industry strivesto adjust to the increase in demand,which is confidently expected tocontinue indefinitely.The predictable and reliableproperties of a hot dip galvanizedcoating for corrosion control havecontributed towards this significantincrease in popularity over the yearsof a coating process which was firstintroduced more than a century anda half ago.The following statistics showconvincingly the substantial increasein demand for hot dip galvanizedsteel during recent years. It shouldbe noted that these statistics (table10) exclude hot dip galvanized wireand continuously galvanized sheet.Hot dip galvanizing is indeed aprocess that can be described as oldyet ever new.The rapid and in some instancesunanticipated increase in quantitiesof steel requiring hot dip galvanizinghas resulted in undesirablyprotracted delivery schedules whichcan impact adversely on completionprogrammes for some projects. Thegalvanizing industry has been madeacutely aware of this negativesituation with the result that manygalvanizers throughout the countryare presently installing additionalfacilities in order to increaseproductive capacity. Dimensionally,the bath sizes in South Africa areequal to the best worldwide withlengths ranging up to 14m in length,2m in width and even 4m deep insome cases.Volume 4 Issue 1 2007 Hot Dip Galvanizing Today 33

Walter’s CornerThe durability of hot dip galvanizingand duplex systems in a vastdiversity of applications issubstantiated by reliable casestudies compiled over many years.It is as a result of the evidenceprovided in these track records thatmore and more specifiers areturning to hot dip galvanizing forgeneral corrosion control in a vastvariety of applications whichinclude atmospheric exposure,immersed and buried conditions aswell as applications wherearchitecturally a structure is requiredto provide an aesthetically pleasingappearance.During 2006, the Internationalproducer prices for numerouscommodities increased significantly.This not only related to productssuch as oil but also to variousmetals ranging from gold, platinumto commodities such as steel.Needless to say, zinc metal has notescaped this trend. Zinc pricestatistics, together with the overalleffect on the prices for hot dipgalvanizing, are illustrated by table 11using approximate figures from theperiod in question.Meanwhile, other protective systemssuch as organic coatings haveescalated in cost to a similar andeven greater extent in line with thesubstantial rise of the producer priceof oil.The question arises; is hot dipgalvanizing still economicallyjustifiable to provide corrosionprotection. The answer to this is ofcourse that, with escalating material,labour and replacement costs, thevalue of equipment requiringprotection is also escalating.When planning a capital project,the important factors to considerare:The required life of equipment andstructures, the degree of corrosion toTable 10: Annual tons galvanized by members.2 years ago 1 year ago CurrentZinc Prices (US$) $1000/ton $1800/ton $3800/ton% Increase +380% +211%HDG Prices (R/Ton) R1600/Ton R2100/Ton R3200/Ton% Increase 200% 152.4%Table 11: Illustration of approximate increases in zinc and hot dip galvanizing over a two-year period.be expected and accessibility formaintenance and replacementwithout sacrificing essentialmaintenance and replacement costsnot to mention lost production timeand safety factors.production time. Over protection isperhaps as undesirable as underprotection,but the usual tendency is The conclusionto under-provide for protection andThe cost of corrosion controlconservation of what is invariablymeasures has increased significantlyexpensive equipment to replace.in recent months due to a largeOne frequently hears the statementextent to increased producer prices“We cannot afford the high costof both zinc (galvanizing) and oilnecessary to provide corrosion(painting). But then again, so hasprotection in this case”. Thethe price of labour and raw materialsappropriate response to thisstatement is frequently “can youafford not to?”Due to a number of reasons, theanticipated lifespan of a mine is notalways easy to predict. This maylead to a conservative predictionwhere a less comprehensive coatingsystem is specified to protect theshaft related steelwork. At the end ofthis period it is frequently decided,for a number of reasons, to extendthe production life of the mine by afurther period, entailing expensivesuch as steel, including stainlesssteel products.As far as zinc is concerned, demandhas exceeded supply for some timewhich has led to increased prices.According to economists thissituation has peaked out and aleveling out of prices is beingpredicted. This is supported by theexpected increase in supplyanticipated as a result of an increasein mining activity by various zincproducers.34 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Member’s NewsZincor to undertake the rebuild of thenumber 4 roasterOwen Tennant, Marketing Manager, ZincorDuring 2007 Zincor plan toundertake the rebuild of the number4 roaster at the plant. The number 3roaster was rebuilt during 2006.This major capital program is in linewith the strategy of Zincor tocontinue to make capital investmentto ensure the continuedsustainability of the operation isSouth Africa.The rebuild will take place over threemonths from June to August 2007.During this time there will be adecrease in zinc production. Zincorplan to import zinc during thisperiod to support the domesticrequirements of zinc.Zincor are currently importing inJanuary / February to ensure that zincstocks are at the required critical levels.It is likely that the zinc price willremain high during 2007 with plentyof volatility expected. Besides thehigh zinc price Zincor expects thatthe demand for zinc will be high,despite the slow start to the year.Zincor wishes all participants in thecorrosion protection industry a verygood 2007.ZincorA Division of Exxaro Base Metals (Pty) LtdSupplier of zinc metal....the answer to corrosion protection.Plover Street, Struisbult, Springs, 1559PO Box 218, Springs, 1560Tel: (011) 812-9500 Fax: (011) 363-3293Website: www.exxaro.comISO14001ISO9001Volume 4 Issue 1 2007 Hot Dip Galvanizing Today 37

Member’s NewsRobor acquisition finalisedRobor, a R1.7-billion a year supplierof world-class steel tube and pipeand related value-added products,has been purchased from theBarloworld Group at a cost of R480-million by a management-leadconsortium. The deal becameunconditional on 1 December 2006,heralding the start of one of very fewcompanies in the industry genuinelyowned by management and staff.With 60 senior staff holding a 44%stake in the company, Robormanagement is confident that themove will unlock the company’ssignificant human capital, facilitatesuperior service from ownermanagersand provide theopportunity to capitalise on thesignificant infrastructural growthexpected in market segments whereit currently operates.These market segments includebuilding and construction, energy,water, mining, automotive and railand logistics. The company is wellfunded by its partners to cope withany growth required to meetincreasing market demands.“We have consolidated the manyproduct brands into the Robor brandand will take a more entrepreneurialapproach that will include enhancedcross-selling, specific marketpenetration and other initiatives,”says Robor CEO, Michael Coward.“The new Robor brand is based on apromise to deliver to ourstakeholders on our core values oftrust, integrity and responsibilitythrough the partnership createdbetween management and ourdedicated staff. We are now incharge of our own destiny, and weintend to leave no stone unturned indelivering our true potential.”BEE Partner Yard Capital makes up18% of the shareholding, withanother 10% held by Robor’s BlackManagement and Staff Trust andRand Merchant Bank owning theremaining 28%. Leslie Maasdorp,Chairman of Yard Capital states,“Yard Capital is proud to be the leadempowerment partner to Robor andthis investment marks our entry intothe manufacturing sector, adding toour portfolio of investments inproperty, IT and the services sectors.We are pleased to be associated withthe Management buy-out of Roborand have full confidence in themanagement team.”Yard Capital intends playing anactive role in the development ofRobor in strategic, operational andtransformational roles to ensureRobor truly takes its place in theSouth African market.The company manufactures hotrolled steel tube and pipe, coldrolled tube, stainless tube and pipeand, open sections, while offeringvalue adding services through pipesystems and hot dip galvanizing. Its’products are grouped under threeprimary divisions. Under theconveyance cluster, Robor groups itsGalvanizing facility, Steel Servicesand Pipe Systems. The structuralcluster is focused on Tube and OpenSections, while the precision clusterincorporates Stainless and PrecisionTube.“Robor’s Galvanizing Business, along standing member of theHDGASA (Hot Dip GalvanizersAssociation of Southern Africa), isSouth Africa’s largest jobbinggalvanizing facility, capable ofprocessing 7 000t/month, with 3galvanizing lines on a single site,”says Gordon Gilmer, chairman of theconveyance cluster. “Our SteelServices business manufactures nonstandardsizes of tubular steel, addsvalue and trades imported items.Pipe Systems' core business is thesupply of 'value-added' steel pipeand complete piping systems, whichcomprises steel pipe (with orwithout various protective coatingsand linings) as well as fittings,flanges and couplings.”Ben de Klerk, Chairman of thestructural cluster says: “Tube is thelargest division in Robor; it is thelargest supplier of longitudinallywelded steel tube in Southern Africa.Utilising the latest production andpaint coating technology, thedivision produces a comprehensiverange of tube and conveyance pipe.”As the original manufacturer of coldformed steel sections in SouthAfrica, Robor's Open Sectionsbusiness has been specialising inthe production of both standard andspecial cold formed steel profilessince 1957. In addition to its valueadding services, which now includepunching, painting and galvanizing,it also carries the best range ofstandard stock products to allow forthe shortest delivery lead times.Stuart Neethling, MD of theprecision cluster, comments:“Precision Tube has beenmanufacturing longitudinally weldedsteel tube from both cold and hotrolled steel since 1946. Extensivefacilities are available to cut, bend,swage, reduce, cold draw andperform many other functions on thetube products offered according tothe specific customer requirements. Iam particularly proud of our newStainless facility at theElandsfontein site, which has fourdedicated mills, laser cutting andother facilities. Stainless is nowpoised to grow significantly invarious selected domestic markets.”38 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

Personality ProfilePersonality ProfileBusisiwe Christina MpontshameDue to the nature of the Industry,the Hot Dip Galvanizing Fraternityhas always been traditionallymale orientated. The few femalesemployed in the Industry, seldomventure out of AdministrativeOffices. We therefore have thepleasure to present theremarkable story of the onlyknown Female Hot Dipper in thecountry…Fate stepped in when a youngwoman from Kwamashu (a vastsprawling township to the Northof Durban) walked down AberdareDrive in Phoenix Industrial Parkto collect money from herboyfriend to fix her rusty oldsewing machine. Sewing &hawking children’s clothing onthe side of the road had been heronly means of income. As sheapproached the gates of PhoenixGalvanizing, the security guard onduty asked whether she would beinterested in a job. PhoenixGalvanizing at the time waslooking to employ females thatfitted a certain criteria to work onthe factory floor as part of thecompany’s Employment EquityPlan. As fate would have itBusisiwe Christina Mpontshamefitted the criteria & walkedthrough the gates of PhoenixGalvanizing, not knowing thatseizing the opportunity wouldchange her life for the better.January 2003 as a “Jigger”. It wasclear from the minute she set footon the premises that this ladyplanned to go places. Her jiggingcareer lasted all of three months,when she was moved into theWeighing Department at her ownrequest. She explains:” When Iwas outside the plant, I didn’treally know what happenedinside. I figured the only way toget to know the business and theprocess was to move around todifferent departments. I also knewBusi, as she is affectionatelyknown on the PhoenixGalvanizing factory floor, startedher career at the company inVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 39

Personality Profilethat nobody would know that,unless I opened my mouth,which I did!” Once Busi“entered” the plant, she foundherself fascinated with theprocess and in particular theactual Hot Dipping Process. Sheenthuses: “The minute I cameinside the plant, I knew I wantedto be a Dipper. It was my dream.I used to think, one day I will bea Hot Dipper.”She expressed her interest inbecoming a Hot Dipper toPhoenix Galvanizing OperationsManager, Dilesh Ramkisson.Dilesh admits that he was quitetaken aback by what he thoughtwas an odd request - comingfrom a girl. He nonethelessdecided to give her a chance andasked the Hot Dipping Team tohelp Busi along. She startedtraining as a Crane Operator andslowly but surely inched her waycloser to the Galvanizing Bath.Busi also immersed herselfvoluntarily in some of the manytraining programmes PhoenixGalvanizing offers to their staffas part of the company’s SkillsDevelopment Programme. Sherealized the importance ofexperiential training and seizedevery opportunity byvolunteering to work weekendsand gaining as much experienceas she could. Of course therewere cynics who didn’t thinkthat a girl would be able to cutit, but her tenacity silenced evenher fiercest critics. She enthusesthat most of her colleagues &especially Phoenix GalvanizingManagement are extremelysupportive of her. Just herexcitement at the recall of herfirst solo dip, “a jig filled withfencing pales”, illustrates thepassion this lady has for her job.A lot of responsibility weighs onthe shoulders of a Hot Dipper,all of which Busi is extremelyaware of. “Mistakes can havedevastating effects and costlives.” This career is also nowalk in the park, astemperatures around theGalvanizing Bath soar, makingwork very uncomfortable andtiring, especially during the hotand humid Durban summersand kitted with the compulsoryPersonal Protective Equipment.Busi is meticulous when itcomes to quality and is aconsummate professional whenit comes to checkingtechnicalities, such as zinctemperature, before dippinggoods. She takes all of the prosand cons of her job in herstride.When Busi is not “dipping away”at Phoenix Galvanizing, she isthe devoted mother of Sfundo,aged 12, who lives with herfamily in Jozini. Busi explainsher vision for the future: “Mygoal in life is to take care of myfamily and my son. Life was hardwhen I was young. I want tobreak that cycle. Being a womandoesn’t limit you in life. Whatmatters is how hard you areprepared to work.” Busi waspromoted to PhoenixGalvanizing’s first female ShiftSupervisor at the beginning of2007. She was also voted asPhoenix Galvanizing’s“Newsmaker of the Year 2006”following her story beingpublished in the PhoenixGalvanizing Annual 2006 (thecompany’s annual magazine thatgets circulated to suppliers andclients). So there you have it –Busi Magic - a true inspirationto all of us!Bread isnowfortifiedwith zinc!South African millers have beenfortifying flour and maize meal with ablend of vitamins and minerals,including zinc, following newlegislation that came into effect inOctober 2003 to improve nutrition inthe country. Millers are now required tofortify white and brown bread flour andmaize meal with vitamin A, thiamine,riboflavin, niacin, pyridoxine, folic acid,iron and zinc."Food fortification is essential toaddress some of the major challengesposed by poverty and malnutrition tothe growth of our nation," HealthMinister Manto Tshabalala-Msimangtold the national press. The SouthAfrican government has received agrant worth US$2.8 million from theWHO-led Global Alliance for ImprovedNutrition (GAIN) to support a foodfortification program. The funding willbe used to support the implementationof the program, helping millers tocomply with the new requirements.Most millers already began fortifyingtheir bread and maize soon after theannouncement of the new regulationsin April 2004. South Africa is one offour countries to receive funding underthe first wave of GAIN grants.China, Morocco and Vietnam will alsoreceive support to improve thenutritional value of their food supplies.40 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

HI-TECH ELEMENTSDESIGNERS AND MANUFACTURERS OF ELECTRICAL HEATING ELEMENTS AND SYSTEMS1126 CBT DESIGN (011) 868 3408With the established infrastructure, we are able to sourceall heating and control products from within our group,ensuring quality and quick and efficient service to ourclients at all times.Hi-Tech Elements, established in 1992 by Andre Goosen andtechnical director Shaun Bester, has grown to become SouthAfrica’s leading supplier of heating, insulation and control for entiregalvanizing plants.The company has the expertise to design, manufacture, install andcommission not only electrical heating elements but all equipmentrelating to the heating industry that would be required in a plant.One of the company’s many successful projects was the design,manufacture and commissioning in 2005 of a very large, completegalvanizing plant in Harrismith, KZN.The expertise within Hi-Tech Elements means that we can consultand advise from the civil and structural layout of the new factory allthe way to the crane size and fitment.Also forming part of the Hi-Tech Group is thechemical heating and control of thepreparation tanks as well as the entiretemperature measurement and control of thezinc tank.Having acquired both Howford Manufacturing(the HotRod ® range of chemical immersionheaters) as well as Eastern Control in the last 5years, we have also fitted our own tube fillingplant, making us unique in the industry.Technically we are able to assist in all sectors ofheating and control for most industries. Wespecialise in designing and manufacturing toclient’s specific needs.The Hi-Tech Group is a member of the Hot DipGalvanizing Association of SA. We are also anISO 9001:2000 certified management group, aswell as having the CE mark worldwide on allour HotRod ® range of products.PO Box 53483 Troyeville 2139Tel: [011] 894 3937 Fax: [011] 894 3954www.hi-techelements.co.zaEmail: andre@hi-techelements.co.za

Guest WriterBob Andrew, our guest writer, is a consulting value engineer and Honourary Life Member of this Association.Like light, people and companies canbe different thingsOne of the strangest ideas ofquantum physics is the ‘wave-particleduality’ of light. Photons, which makeup light, exist as particles and wavesat the same time. They are bothparticles and waves.The characteristics of waves andparticles are necessary for a fulldescription of what light is. Asobservers, however, we cannotmeasure this duality, we cannot seewhat light is really like. If we treatphotons as particles, we candetermine their exact position butnot their energy. If we treat them likewaves, we can determine their energybut not their position. They areindeterminate and become only whatwe measure them to be.In the quantum world, bothdescriptions of light are equally validand complementary. Neitherdescription is complete in itself.There are circumstances where it ismore appropriate to talk of light asparticles and circumstances where itis better to think of waves. Thisschizophrenic personality of light iscalled ‘complementarity’.The ‘both/and’ character of light is farremoved from our mechanistic anddeterministic world, which has an‘either/or’ nature about it. In ourworld, we think of objects as definitethings, which we can accuratelymeasure. While the environmentmight change them, they do notchange internally-they do notbecome something else; they remainwhat we see them as.Quantum theory means uncertainty.We can never be sure what we aremeasuring since the act ofmeasurement affects the thing beingmeasured. The more accurate themeasurement, the more the item isaffected. The measurement definesthe thing being measured. Themeasurer influences themeasurement.New Age philosophers, like DanahZohar and Ian Marshall (TheQuantum Society) have begun torealise that people may also possesscomplementarity. They can havemore than one characteristic: theycan be both one thing and another atthe same time; it depends on whatwe measure them as. We cannot,however, measure them completely;we cannot fully describe them.Whatever we describe people as therewill always be some indeterminacyabout the person-something we cannever describe. The way we measurepeople will define the characteristicwe are measuring.In quantum theory terms, there is nopoint in judging people by measuringtheir intrinsic properties, such as IQ,dexterity, literary comprehension, etc.These measurements will always beincomplete. People should rather bemeasured by their behaviour in givencircumstances. When they are judgedon their behaviour alone, thequantum uncertainty of theirpersonality disappears for that set ofconditions we place them in.Quantum theory also suggests thattwo people can have different viewsof the same matter and yet be equallyright. It is therefore illogical to judgepeople on their views. The peopledoing the judging will influence theviews.Alfred Korzybski, as long ago as1933, (Science and Sanity) recognisedthat viewing people in quantumtheory terms required a newlanguage, which he called ‘English-Prime’ or ‘E-Prime’. In E-Prime, theword ‘is’ is removed. Instead ofsaying: “John is lazy”, in E-Prime wewould say: “John appears to be lazy inthe office today”. “John is a racist”would become “John has some racistideas which I find offensive” and soforth. One can never be sure exactlywhat a person is really like and ourlanguage should reflect this.Quantum theory can destroy themyth that a company has to be onething or another. Many companiesbrutalise themselves by sticking tothe seemingly rational policy thatthey can’t be two things at the sametime. Stability or progress,conservative fiscal policies orentrepeneurship, home-grownmanagers or imported skills is thedilemma that many companies face.In the quantum world, companies donot have to wrestle with theseparadoxes; they do not have to worryabout being ‘either/or’, they thinkalong ‘both/and’ lines. They seekopportunities in both directions.The classical ideal of a securedeterministic world, waiting out thereto be analysed and exploited, doesnot fit into quantum theory. Instead,we must regard ourselves asinalienable participants in anindeterminate world.42 Hot Dip Galvanizing Today Volume 4 Issue 1 2007

No. 13/2007Case StudyMoma Sands Project, MozambiqueThe ApplicationThe extensive use of hot dipgalvanizing for structural steelcomponents on an extremely remotesite where logistics, materialshandling, transport and co-ordinatedplanning had a profound influenceon the project timing andcompletion date.Environmental ConditionsThe corrosive conditions encounteredat this remote location can beclassified as a C4 or a C5environment in terms of ISO 9223. Interms of this classification andconsidering the hot humidenvironment, in a marine location, aC4 or “Exterior industrial inland orurban coastal” conditions areconsidered applicable. Zinc corrosionrates for this environmentalclassification is estimated in therange of 2 to 4 micron (µm) per year.Considering the actual siteconditions, the expected corrosionrate of zinc would be approximately 2to 3µm per year. Assuming theseenvironmental conditions theestimated “Service life” of the hot dipgalvanized structural steel would bein excess of 30 years before 1stmaintenance.The SiteOne of three such structures, where refined products will be stored prior to conveyance, via anoverland conveyor, to a specially constructed loading pier, for loading onto sea-barges fortranshipment to ships anchored offshoreThe site is located on theMozambique coast approximately 30minutes flying time north of Beira.The project involved the design, offsite fabrication of steel and hot dipgalvanizing, followed by the logisticsof loading, ocean transportation ofthe entire project facilities, transshipping,via a sea barge to thebeach, haulage inland over a distanceof 3 to 4 kms to the various sitescomprising the project. The projectrequired integrated logistics planningand co-ordination of all supplyarrangements. No infrastructure orformal facilities existed prior to thecommencement of the project.Our FindingsThe use of hot dip galvanized steel,in the given corrosive environment,will provide an expectedmaintenance free service life inexcess of 30 years. This estimate isconservatively based on the meanzinc coating thickness of 85µm and acorrosion rate of between 2 and 3µm per year. The actual coatingthickness measured during our sitevisit was generally found to be wellin excess of 100µm and more oftenthan not in excess of 120µm.Alternative corrosion controlcoatings can not match theHot Dip Galvanizers Association Southern AfricaUnit U4 (Upper Level), Quality House, St. Christopher Road, St. Andrews, BedfordviewP.O. Box 2212, Edenvale, 1610 • Website: www.hdgasa.org.za • E-Mail: hdgasa@icon.co.za

Case Studyperformance of hot dip galvanizingwhen one considers the roughhandling involved in loading,transportation and offloading atsuch an isolated site. Designrequirements of durability andlongevity were achieved by way ofthe metallurgically bonded hot dipgalvanized zinc coating, both fromthe standpoint of a “barrierprotection” as well as “cathodicprotection”. Handling damage, repairof which was achieved by theapplication of a suitable zinc richepoxy, does not compromisecorrosion control, due to cathodicprotection characteristic ofgalvanized steel. The same repairprocedure was applied to theisolated occasions where sitemodifications were found to benecessary.The sea pier and conveyor termination from where refined product will load onto sea-barges fortrans-shipment to ships anchored off shore.ConclusionThe primary features and benefitsachieved on this project were:1. Cost and economic effectivenessof hot dip galvanizing, given thesite location and availability oflocal materials and equipment.2. The effective use of hot dipgalvanizing in a C4 environment,i.e. marine conditions anddesigning the corrosion controlsystem to suit the givenenvironment and service liferequirements.General view of part of the "dry plant" under construction, which will ultimately be used in therefining of titanium products.3. Versatility of steel and the provenand effective methods used tocombat corrosive elementswithin the given environment.The benefits and economics of hotdip galvanizing on large projects,situated in remote locations thatinvolve special logisticalarrangements, extreme andchangeable weather conditions areagain reaffirmed by this case study.The starting point of the 4km overland hot dip galvanized conveyor that ends at the sea pier fromwhere refined products will be loaded onto sea-barges.Hot Dip Galvanizers Association Southern AfricaUnit U4 (Upper Level), Quality House, St. Christopher Road, St. Andrews, BedfordviewP.O. Box 2212, Edenvale, 1610 • Website: www.hdgasa.org.za • E-Mail: hdgasa@icon.co.za

MembershipCOMPANY LOCATION CONTACT TELEPHONE E-MAIL MAIN CLASS OF WORKCORPORATE MEMBER – CORPORATIONS WHICH HAVE INTERESTS IN THE ASSOCIATIONZinc Corporation Springs Owen Tennant 011 812 9500 info@zincor.co.za Producers of refined zinc metal for the galvanizing industryINTERNATIONAL MEMBER – A GALVANIZER OR RELATED COMPANY BEYOND THE BORDERS OF SOUTH AFRICAKingfield Equipment (Pty) Ltd Victoria, Australia Geoff Lisle +613 9876 9190 geoff@kingfieldequipment.com.au Suppliers and designers of hot dip galvanizing equipmentand furnaces.Gimeco Srl Trezzano Rosa, Italy Ermes Moroni +39 02 909 60751 gimecoita@tin.it Engineering and manufacturing of hot dip galvanizing linesASSOCIATE SUPPORT MEMBER – SUPPORT COMPANIES THAT PURCHASE AND SELL TO THE INDUSTRYChemplus Roodepoort Charles Starck 011 760 6000 chemplus@mweb.co.za Manufacture of speciality process and finishing chemicalsto the hot dip galvanizing IndustryHighveld Steel andVanadium Corp Ltd Bedfordview Stuart Gray 011 454 1583 stuartg@hiveld.co.za Supplier of hot rolled structural sections, plate and coil.Metsep (Pty) Ltd Denver Robert Watchorn 011 626 2425 robert@metsep.co.za Supplying pickling plants with inhibited hydrochloric acidand removing and regenerating the spent pickle liquor inan environmentally friendly mannerMR Zinc Oxide (Pty) Ltd Dalpark Mike Robertson 011 915 1828 Mr.zinc@mweb.co.za Manufacturer of zinc base alloys, marine anodes, zincoxides – Traders of zinc ingots and purchaser of all typesof zinc residues/scrap.CSO – A division of Bedfordview Lynnette Vanvreden 011 457 2400 Ryszard.orlik@chemsystems.co.za Manufacture of speciality metal finishing chemicals to theChemserveSystems (Pty) Ltdhot dip galvanizing, electroplating, anodising, wire drawingand powder coating industries.Surface Treatment Jupiter Donavan Jones 011 626 1292 sttchem@mweb.co.za Manufacture, supply and servicing of speciality metalTechnologiestreatment chemical products and coatings to the hot dipgalvanizing, powder coating, wire drawing, anodising andpaint market.ASSOCIATE GALVANIZING MEMBER – A DEVELOPING GALVANIZER WHO HAS BEEN IN BUSINESS FOR LESS THAN A YEARPinetown Galvanizing Pinetown Shainil Doorjan 082 353 0891 GalvanizerAFFILIATE COMPANY MEMBER – COMPANIES THAT SELL HOT DIP GALVANIZED ARTICLESAdvanced Roof Technology Illovo Tanya Wolverson 011 605 2510 Info_artf@mweb.co.za Advisory and practicing association of advanced levelFoundation – ARTFconsultants, engineers, inspectors and paint applicators, inthe roofing field.Andrew Mentis Elandsfontein Ted Jarvis 011 255 3200 tjarvis@mentis.co.za Manufacturer of steel products including expanded metal,steel floor grating, Mentrail guard rail and industrialhandrailing systems.CWI Vanderbijlpark Craig Viljoen 016 980 3111 craigvil@cwi-wire.co.za Manufacture of galvanized wire and wire products.Duplex Coatings cc Wadeville Mike Book 011 827 4221 mike@bulldogprojects.co.za Specialists in the painting of hot dip galvanized substrates.Eskom Energy Services Durban Gail Perry 031 792 8600 energyservices@eskom.co.za Performance contracts with industrial customers to keepenergy costs low and process efficient.Fairmile Fencing SA (Pty) Ltd Brakpan Jaco Viljoen 011 743 2080 Stefan@fairmilefence.co.za Palisade fencing, razor wire, section rolling and reinforcingsteelGalvfast Trading Birch Acres Arthur Harwood 011 391 3115 arthureh@mweb.co.za Specialist supplier of hot dip galvanized and industrialfasteners to the construction industry.Hi-Tech Elements (Pty) Ltd Boksburg Andre Goosen 011 894 3937 andre@hi-techelements.co.za Design and manufacture of heating elements, systems andcontrol for the hot dip galvanizing industry.Jostech Fire Services cc Birch Acres Daryl Johnston 011 976 5097 jostech@mweb.co.za Design, manufacture and installation of ceramic fibreinsulation linings.O-line Support Systems Selby Graeme Smart 011 378 3700 o-line@o-line.co.za Electrical and mechanical support systems and powder coating.Rand York Castings Umhlanga Rocks Lance Corbett 031 561 1023 sales@randyork.com Fabrication of special steel profiles for civil and mining sectors.Robor Pipe Systems Isando Jim Begbie 011 974 3351 jimb@robor.co.za Supply of value added steel pipe and complete pipingsystems with various protective coatings.SA Galvanizing Services Pretoria Johan du Plessis 012 996 0458 sagalv@eject.co.za New hot dip galvanizing plant design, installation and(Pty) Ltd 011 422 2832 project management technology experts.Strutfast (Pty) Ltd Denver Pieter Uys 011 622 9969 sales@strutfast.co.za Suppliers of electrical cable support systems.T & E Chamdor Jack Siebert 011 762 1084 trucking@trucking.co.za High and low pressure piping, stainless steel, steelworkand platework.Weartech (Pty) Ltd Wadeville Simon Wintle 011 824 6010 simon@weartech.co.za Suppliers of zinc thermal spray equipment, spare partsand wire.Zinchem Benoni Adrian Marini 011 746 5000 sergiom@zinchem.co.za Converters of primary and secondary zinc to superior qualitychemicals and metals in accordance with the highestinternational standards.AFFILIATE PROFESSIONAL MEMBER – SPECIFIERS WHO HAVE AN INTEREST IN THE ASSOCIATIONCorrosion and TechnologyReputable independent Corrosion and AC Mitigation ConsultingConsultants Bedfordview Gerald Haynes 011 456 7960 gjhaynes@icon.co.za Engineers and Project Managers.AFFILIATE COATING INSPECTOR MEMBER – APPROVED COATING INSPECTORSBertus Fourie Cleveland - 076-051-1682 bfourie@roshcon.co.zaTekkies Kruger Newcastle - 083-273-4684 tekkies.kruger@eskom.co.zaKeith Moodie Polokwane - 015-291-2020 pbg@evn.co.zaJan Stander Vorna Valley - 011-800-4683 jan.stander@eskom.co.zaVolume 4 Issue 1 2007 Hot Dip Galvanizing Today 45

HOT DIP GALVANIZING MEMBERSGALVANIZER LOCATION TEL. NO SPIN NO. OF BATH SIZESLINES (L x W x D) (m)GAUTENGArmco Galvanizers Isando 011 974-8511 1 13.2 m x 1.5m x 2.0mArmco Galvanizers – Dunswart Dunswart 011 914-3512 ● 3 5.2m x 1.2m x 2.0m3.0m x 1.0m x 1.5m2.0m x 1.0m x 1.5mBabcock Nthuthuko Powerlines (Pty) Ltd Nigel 011 739-8200 1 12.0m x 1.4m x 1.8mCape Gate (Pty) Ltd Vanderbijlpark 016 980-2270 # Wire galvanizerDB Thermal SA (Pty) Ltd Nigel 011 814-6460 # In-line galvanizerGalvadip (Pty) Ltd Waltloo 012 803-5168 1 7.2m x 1.5m x 1.8mGalvrite Galvanising (Pty) Ltd Randfontein 011 693-5825 1 6.5m x 1.3m x 2.0mGEA Air Cooled Systems Germiston 011 861-1571 # In-line galvanizerLianru Galvanisers cc Nigel 011 814-8658 2 7.2m x 1.3m x 1.6m1.95m x 0.83m x 1.2mMacsteel Tube & Pipe Boksburg 011 897-2194 # 13.5m x 1.6m x 2.4mMittal Steel SA Vereeniging 016 889-8816 # Sheet galvanizerPro-Tech Galvanizers (Pty) Ltd Nigel 011-814-4292 ● 2 3.0m x 1.1m x 1.2m3.2m x 1.1m x 1.5mRobor Galvanizers Germiston 011 876-2900 2 14m x 1.35m x 2.5m10.0m x 2.0m x 4.0mTube Dia 42mm to 114mmmax tube length 6.7mRobor Tube Elandsfontein 011 971-1600 # Pipe plantSupergalv Alrode 011-908-3411 1 6.0m x 1.2m x 1.8mMPUMALANGAChevron Engineering (Pty) Ltd Barberton 013 712-3131 1 Dia 0.7 x 1.2dNORTH WESTAndrag Agrico Lichtenburg 018 632-7260 # In-line galvanizerWESTERN CAPEAdvanced Galvanising Corp. Bellville 021 951-6242 1 8.0m x 1.5m x 3.0mCape Galvanising (Pty) Ltd Parowvalley 021 931-7224 1 14.0m x 1.6m x 2.6mGalvatech (Pty) Ltd Bellville 021 951-1211 1 7.5m x 1.5m x 2.6mHelderberg Galvanizing Strand 021 845-4500 1 5.5m x 0.8m x 2.4mProGalv cc Stikland 021 945-1803/4 1 7.2m x 1.3m x 2.6mSouth Cape Galvanizing (Pty) Ltd George Industria 044 884-0882 1 5.5m x 1.0m x 2.6mEASTERN CAPEButterworth Metal Industries Butterworth 047 401-3600 1 1.2m x 0.6m x 0.8mGalvanising Techniques cc Port Elizabeth 041 486-1432 1 12.0m x 1.3m x 2.3mGalvaspin (Pty) Ltd Port Elizabeth 041 451-1947 ● 1 3.0m x 1.2m x 1.8mMorhot (Pty) Ltd East London 043 763-1143 1 6.0m x 1.2m x 2.5mKWAZULU/NATALA&A Galvanisers Pietermaritzburg 033 387-5783 ● 1 3.3m x 0.95m x 1.9mBay Galvanisers Richards Bay 035 751-1942 1 5.0m x 1.2m x 2.5mPhoenix Galvanizing (Pty) Ltd Phoenix 031 500-1607 ● 3 14.0m x 1.4m x 2.5m7.0m x 1.2m x 3m3.0m x 1.2m x 1.2mVoigt & Willecke (Pty) Ltd Durban 031 902-2248 1 9.0m x 1.2m x 2.5mThe bath dimensions provided in this schedule are actual dimensions. Please check with your galvanizer the actual component size that canbe accomodated, either in a single dip or by double end dipping.# Sheet, Wire, Tube and In-line galvanizing members dedicate their plants to the galvanizing of their own products.For specific contact names (eg. sales or production personnel) and mobile telephone numbers, kindly contact the company receptionist.