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Reliable and efficient four-stroke small-bore engines

Regulatory and fuel-related uncertainty can make it difficult to plan investments in propulsion and GenSets. With our small-bore engines, you are prepared for whatever lies ahead.

MAN Energy Solutions has built its position as the leading designer and developer of small-bore engines for the world’s merchant marine fleet on the basis of high reliability and efficiency.

Thanks to the low maintenance requirements, our engines provides extended lifetime, and additionally offer long time between overhauls (TBO). When needed, our service experts are there for you – every day and everywhere around the world.

MAN small-bore engine portfolio for the world’s merchant fleet

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More than
20000
MAN Energy Solutions small-bore engines are in service today
MAN PrimeServ
24
/7
service with passion
across the globe

Key benefits

  • Proven reliabilty

    Our small-bore engines are designed for lifelong operational reliability, availability and minimal downtime – they are ready and up running when you need them. Sturdy engine blocks, stiff crankshafts and robust connecting rods are just some of the basic design characteristics which secure trouble-free operation and long overhaul intervals.

  • High efficiency

    Efficient performance has a measurable effect on both the environment and your bottom line. It also explains why more than 19,000 of our engines are in service worldwide. Our dual-fuel engines let you select the most economic fuel type for the operating conditions. The cost optimized fuel injection system is also designed for high reliability and cost-efficiency.

  • Future-proof solutions

    The main uncertainties affecting engine choice have to do with the environmental and cost factors of fuel. Our answer is flexibility. Our single-fuel engines can run on conventional fuel types and also bio-fuel oils. Dual-fuel engines let you use methane as additional fuel type. The MAN L21/31DF-M and MAN L27/38DF-M can use methanol as second fuel type.  Our retrofitting expertise offers flexibility, now and in the future.

Full range of MAN four-stroke small-bore engines

Explore the capabilities and range of our engines.

GenSets and Diesel-electric propulsion

MAN L28/32DF GenSet

Based on the ultra-reliable and robust MAN 28/32H, the dual-fuel version is available as newbuild or retrofit and adds the ability to run on methane, with its economic and environmental advantages. High efficiency in gas and diesel mode makes it a perfect GenSet as part of a complete power package with four-stroke or two-stroke propulsion engines. Easy operation, easy maintenance and proven reliability also make it a trusted propulsion engine with long times between overhauls and low life cycle costs.

  • 720 – 750 rpm
  • 1,050 – 1,890 kW
  • 1,000 – 1,800 kWe

MAN L23/30H Mk3 GenSet

By applying innovative technology to classic design principles, the MAN L23/30H Mk3 is engineered to meet the power needs of most commercial ship types. Straight forward integration requirements make it a perfect choice for low-cost installation, while well-known maintenance procedures and common spare parts reduce operating costs. The new model raises power output per cylinder by 15-20% and reduces fuel oil consumption.

  • 720 – 900 rpm
  • 500 – 1,800 kW
  • 475 – 1,710 kWe

MAN L23/30DF GenSet

The MAN L23/30DF dual-fuel GenSet lets you select the most economic fuel for the operating condition. The cost optimized fuel injection system is designed for high reliability and cost-efficiency. It uses the main injection valve to inject pilot oil. This way, separate injectors, piping and pumps for main oil and pilot oil or a common rail system are not needed, saving on installation costs and maintenance. The monocoque design also eases the installation of the engine series and reduces weight.

  • 720 – 900 rpm
  • 625 – 1,320 kW
  • 590 – 1,255 kWe

This methanol-fuelled engine is a compact and reliable power source designed to run on methanol, heavy fuel oil (HFO), and most bio-fuel oils. When powered by green methanol, it is carbon neutral. The new engine type maintains the reliability and low consumption of the proven MAN 21/31, ensuring security of power supply on large vessels and handling load steps with confidence.

  • 900 – 1,000 rpm
  • 1,000 – 1,980 kW
  • 950 – 1,880 kWe

This GenSet operates at the lowest possible accumulated costs during their complete life cycle thus providing a safe investment.

A methanol conversion will be available soon as a retrofit for existing MAN 21/31 GenSets.

  • 900 – 1,000 rpm
  • 1,000 – 1,980 kW
  • 950 - 1,880 kWe

Propulsion engines

The robust and reliable MAN L27/38 delivers good performance over the entire load range with quick acceleration and immediate load response. Its proven reliability ensures long time between overhauls (TBO) and no unscheduled maintenance or repair work.

This engine is available as methanol-ready version.

  • 750 – 900 rpm
  • 2,100 – 3,690 kW

MAN L21/31 propulsion

The MAN L21/31 engine combines intelligent use of fuel in marine applications with flexible propulsion systems. It is the ideal power source, for example, for small to medium-sized tankers, cargo ships and ferries.

The proven engine is characterized by its reliability and low consumption. 

This engine is available as methanol-ready version.

  • 1,000 rpm
  • 1,290 – 1,935 kW
36000
h
time between overhaul extensions possible

Plan your vessel with confidence

Get in touch with our four-stroke small-bore experts for in-depth advice on all your propulsion and GenSet questions. Start your change process now and reach out to us today.

Contact our experts

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Related news

Wednesday, September 4, 2024

MAN PrimeServ Hamburg Gears Up for Future

MAN PrimeServ's largest service centre adopting repair and conversion concept for future; ability to handle new fuels, new machines and processing technologies seen as answer to market challenges

MAN Energy Solutions’ largest service-centre has announced changes to its core concept to adapt to the changing times the maritime service industry is currently experiencing. MAN PrimeServ, Hamburg has cited the emergence of alternative fuels, larger ships and shorter harbour-stays as general trends within the industry with the bulk of business shifting to the workshop and components, or with superintendents travelling to wherever ships are docked to work in situ.

Stefan Eefting, Senior Vice President and Head of MAN PrimeServ Germany, said: “Our Hamburg site has developed its own concept to address these new market trends. Accordingly, it is expanding its workshop and developing its specialisation in repair technologies. The future is about new welding technologies, in-situ machining of components and extending the service-life of components – not to mention the associated reduction in CO2 emissions compared to manufacturing a new part.”

Located in the heart of the port, and specialising in the repair and maintenance of both two- and four-stroke marine engines, as well as turbomachinery, MAN PrimeServ Hamburg has 300 employees and approximately 30,000 m2 of factory space.

Olaf Gunia, Head of MAN PrimeServ Hamburg, said: “Our investment in new machines for processing components includes a machining centre that reduces the machining time for certain components like piston-crowns, cylinder covers, flywheels and counterweights for crankshafts by a factor of four. These shorter processing times are intended to take account of the shorter harbour stay-times of the ships and will reduce costs, which of course will be passed onto customers.”

Conversions

Another new field for Hamburg will be the conversion of diesel engines to dual-fuel technology by service engineers in Hamburg and with the help of MAN PrimeServ’s international network, should travel be called for. Such projects require complex planning, not only in terms of technicians and tools, but also the dispatching abroad of any components required by the host vessel. 

Gunia added: “We are preparing for conversions, procuring the necessary tools and training employees to handle the new fuels. Recruiting qualified personnel is a current challenge but we are steadily adding to our roster with experienced engineers and skilled trades people such as machine fitters, welders and machining technicians. New times demand new approaches and I am confident that PrimeServ Hamburg is well-positioned for the future."

Documents

  • PR SMM PServ Hamburg_EN
    PDF, 252 KB English

Images

  • Red_MAN_Halle_2024_042
    JPG, 945 KB English
  • Red_MAN_Werkstatt_2024_016
    JPG, 1432 KB English

Contact

Nils Søholt

Trade Press Marine

Group Communications & MarktingMAN Energy SolutionsTeglholmsgade 412450 Copenhagen SVDenmark

t +45 33 85 26 69

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