Download - Shipandoffshore.net

Monday, May 13th
Tuesday, May 14th
Wednesday, May 15th
Thursday, May 16th
In recent years, the market for small bore four-stroke gensets
and small bore four-stroke propulsion engines has moved to
the Far East. The organisation and handling of these engines
have changed accordingly within MAN Diesel & Turbo. In 2011,
the responsibility for the MAN Diesel & Turbo small bore fourstroke
engines shifted to Denmark. Our duty and commitment
is to be the preferred licensor. We have changed the organisation
in Denmark in order to be able to handle this new responsibility
with a strong focus on engineering, R&D, promotion,
support and troubleshooting service. Thus, we are launching a
number of initiatives to further improve the performance of the
engines as well as to update the small bore four-stroke engine
programme. Over the years, a comprehensive amount of technical
modifications has been introduced to the engines. These
modifications have been implemented to counteract problems
occurring in service as well as to reduce production costs. This
paper describes the service experience of the large number of
GenSet engines, propulsion engines and engines in power stations
with a detailed explanation of what has been done to cure
the problems experienced. In the paper we also describe how
these findings and countermeasures will make it possible to increase
the recommended time between overhauls, depending
on engine type. We have released a number of design changes
to the small bore engine programme with a view to further increasing
the competitiveness of the engines. Furthermore, we are
launching a new engine type in the programme. A description
of what has been done, engine design details as well as what is
in the pipeline for the future, will be included in the paper. The
paper also outlines how MAN Diesel & Turbo cooperates with
the licensees worldwide. Our licensees contribute with production
know-how, design optimisations, standardisations, shipyard
feedback, local market overview and overall experience. All
these contributions and our own know-how will be reflected in
our new engines.
Tuesday May 14th / 13:30 – 15:00 Room B
Product Development
Gas and Dual-Fuel Engines – Controls and Emissions
The new Bergen B35:40 lean-burn marine gas engine
series and practical experiences of SI lean-burn gas
engines for marine mechanical drive
Erlend Vaktskjold, Rolls-Royce Marine AS Engines-Bergen, Norway
Leif-Arne Skarbo, Rolls-Royce Marine AS Engines-Bergen, Norway
Kurt Valde, Rolls-Royce Marine AS Engines-Bergen, Norway
Ketil S. Foer, Rolls-Royce Marine AS Engines-Bergen, Norway
Thor Humerfelt, Rolls-Royce Marine AS Engines-Bergen, Norway
Rune Nordrik, Rolls-Royce Marine AS Engines-Bergen, Norway
Bjorn O. Bruvik, Rolls-Royce Marine AS Engines-Bergen, Norway
The pioneering Bergen SI lean-burn marine gas engine portfolio
has been established and launched to the market through
the previous eight years. The marine gas engine portfolio builds
on the strong pedigree of the Rolls-Royce Bergen lean-burn SI
gas engines for land-based power applications. The first steps
towards the marine gas engine applications were taken by the
initial adaptation of the classic KV-Gas series for gas electric propulsion
in a series of Norwegian car passenger ferries in 2006.
The first 16 engines have now accumulated more than 500,000
running hours with individual engines at 41,000 hours +. The
next move was the introduction of the B35:40V marine gas series
in 2008, and the newly designed C26:33 L-series in 2010.
Both of which have been put to use in mechanical drive variable
speed applications. In 2012 the range was completed by
the introduction of the B35:40-L-series. The development of the
marine gas engines aims at mechanical drive propulsion application
as well as marine genset applications, both incorporating
the ’Inherently Safe Gas Concept’ with double-walled gas
supply systems with ’block and bleed systems’ installed. Strong
aspects of the marine lean-burn gas engines are low specific fuel
consumption, good transient load performance combined with
very low NOx, SOx, CO 2
and UHC emissions. This paper will
concentrate on:
a) The development of the B35:40-series with emphasis on the
L-version;
b) Reviewing experience and practical aspects of lean-burn gas engines
in general and marine mechanical drive variable speed applications
in particular.
a) Engine Design: The B35:40L marine gas series is a relatively
compact design comprising a 350mm bore on a 520mm cylinder
distance. The stroke remains at 40mm as for the V-version. Also,
the engine series is equipped with the latest version of the fuel gas
piping system where the engine is fed with a single pressure regulated
gas supply which is split on the engine between prechamber
and main chamber supply. This design allows a simplified piping
arrangements on the engine and between the gas regulating ramp
and engine without any sacrifices in performance.
b) Practical aspects of using SI lean-burn marine gas engines: Applications
so far employed and to be covered in this paper are:
ferries for passenger and cars, cargo ships, RoPax ferries and tug
boats with both gas-electric and mechanical drive of controllable
pitch propeller, variable speed and variable load, also twin-inputsingle-output
gearbox applications, including individual requirements
for different applications.
Included is also a review of the engine operation limits, as employed
in the Bergen lean-burn marine applications, showing how
transient loading limits and load increase rates affect the applications
of Bergen lean-burn gas engines.
Development and application of low concentration
mine gas engine
Guochang Zhang, Shengli Power Machinery Co, Ltd, China
Shanxiang Mu, Shengli Power Machinery Co, Ltd, China
Kangyao Deng, Shanghai Jiao Tong University, China
Shuan Qu, China North Engine Research Institute, China
When volume fraction of mine gas reaches 5% ~ 15%, it will explode
in case of fire. For the mine gas with a concentration of under
25%, the traditional approach is to extract the wet mine gas
and discharge it to the air, which is a waste of resources, and endangers
environmental protection. China has rich gas geological
storage. According to estimation of concerning department, the
annual emission of mine gas is about 13.5 billion cubic meters
during the process of coal mining, more than 90% of which has
a methane concentration of under 25%. In order to effectively
utilise the low concentration gas, Shengli Power Machinery Co
Ltd developed 12V190 gas engine, which can use mine gas with
methane concentrations in the range of 6% ~ 30%. This paper
introduces low concentration gas safety conveying technology,
engine control system, as well as research on engine performance
improvements. The gas delivery system uses techniques
including waterblock fire arrestor technology with automatically
controlled water level, corrugated-metal-strip gas pipeline
fire extinguishing technology and water mist fire extinguishing
technology. Engine control technologies include double butterfly-
gate mixer, low-pressure and large-flow pilot valve pressure
control and TEM electronic management system. Through the
use of prechamber spark plug and high efficiency turbocharger,
May 2013 | Schiff&Hafen | Ship&Offshore SPECIAL 33