MAN launches new medium speed dual-fuel engine platform

MAN Energy Solutions’ new MAN 49/60DF engine type was launched at the SMM trade fair in Hamburg on 6 September.

The new engines are claimed to offer a 13% increase in power per cylinder, while offering a 3% reduction in fuel consumption in gas mode compared with existing engines in the range.

This allows the engine to achieve “best in class” efficiency, with SFC in gas mode of 6,990 kJ/kWh. The engine was also able to achieve SFOC of 171g/kWh.

The 49/60 platform will consist of 6, 7, 8, 9, and uniquely a 10-cylinder in-line variant spanning a power range from 7,800kW to 13,000KW. A range of 12 and 14-cylinder v-engine are also being introduced. The engines are said to be suited to numerous types including cruise vessels, ro-ros and ro-pax vessels.

The engine also features two-stroke turbocharging supplied by MAN’s turbocharging subsidiary. The use of two-stage turbocharging has contributed to the improvement in the engine’s performance, allowing the use of Miller Timing, and higher pressure ratios.

Marita Krems, Head of Four-Stroke Marine & License, MAN Energy Solutions told The Motorship that the improvement in efficiency also reflected the use of MAN’s next generation Adaptive Combustion Control ACC 2.0, which automatically sets combustion to optimum levels, as well as success in lightweighting components within the design.

The engine also featured the first use of a new 2.2 Common Rail System, as well as an upgraded version of MAN’s SaCoS5000 automation system.  

As a result, the engine will allow a 40% reduction in methane emissions, when operating in gas mode, compared with existing engines in the range. The benefits were not limited to operations in gas mode: a “significant” improvement in fuel consumption in diesel mode has also been achieved.

The increase in power means the same power demand can be met with fewer cylinders. This will offer opex cost advantages, Krems noted. 

The engine also retains existing MAN technologies such as the gas-injection system, pilot-fuel-oil system and MAN SCR (Selective Catalytic Reduction) system.

The new dual-fuel engine is capable of running on LNG, diesel and HFO as well as a number of more sustainable fuels including biofuel blends and synthetic natural gas. 

The 49/60DF is already available for order, with the first type approval test expected to occur in March 2023, Krems noted.

Multiple compliancy paths

The 49/60 can start in gas mode where it complies with IMO Tier III without secondary measures. In diesel mode, it complies with Tier III combined with MAN’s SCR system.

In addition to the methane emissions improvement, soot emissions are halved in diesel mode due to MAN’s new common rail system 2.2. The engine’s benchmark efficiency and fuel-flexible design offers multiple paths to emission compliancy leading up to 2050, as per the current Fuel EU draft.

MAN Energy Solutions plans to introduce a pure diesel engine based on the 49/60 platform in 2023 that will inherently be retrofit-ready for running on methanol and LNG should the demand arise at a later stage.