Main Engine 4-Stroke · Main Engines (4-Stroke)
This is a medium-speed marine diesel engine. The Wärtsilä 12LW31 boasts a powerful output of 6240 kW. It belongs to the W31 family of engines and features a 12-cylinder, in-line (L) configuration with a bore of 310 mm and a stroke of 430 mm. The engine operates at 750 rpm and is fueled by both Heavy Fuel Oil (HFO) and Marine Diesel Oil (MDO), utilizing Common Rail technology. The Wärtsilä 12LW31 is turbocharged with an intercooler for efficient combustion. This engine delivers a consistent 325 kW per cylinder across all configurations. The verified specifications include a Mean Effective Pressure (MEP) of 25.5 bar at 900 RPM and 24 bar at 1000 RPM, a Piston Speed of 9.6 m/s at 900 RPM and 10.7 m/s at 1000 RPM, and an SFOC (ISO conditions, 85% load) of 186-192 g/kWh. It is categorized as a legacy engine with production discontinued in 2010, with approximately 720 engines manufactured since a 1996 redesign.
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