OceanSphereENGINES

12LW34SG

Main Engine 4-Stroke · Main Engines (4-Stroke)

Technical data from manufacturer or class sources · not yet verified by a person​‌​​‌​​⁠​‍​‌‍‍‍⁠‌‌​‍
5,760 kWPower
12Cylinders
340 mmBore
400 mmStroke
10 454 x 3 350 x 4 374Dimensions

The Wärtsilä 12LW34SG is a 12‑cylinder, spark‑ignited lean‑burn marine gas engine delivering roughly 6 MW at 750 rpm, designed for natural gas, biogas or low‑carbon gaseous fuels.

Specifications

Technical data.from datasheet

Every value below comes from the manufacturer datasheet or class-society record on file for this model.

Power per cylinder (main engine 34DF)500 kW @ 750 rpm
Power per cylinder (auxiliary 34DF)520 kW @ 720-750 rpm
Mean effective pressure (main)20.0-19.8 bar
Piston speed9.6-10.0 m/s
Compression ratio (16V/20V)12.6:1
Engine type4-stroke, turbocharged intercooled non-reversible
Swept volume per cylinder36.3 dm³
34DF Max output (16V main)8000 kW
34DF/34SG Max output (20V genset)9800 kW
34SG designSpark-ignited, lean-burn, pre-chamber
20V34SG dimensionsL:12.7m × W:3.3m × H:4.65m
20V34SG weight131,500 kg
Dimensions10 454 x 3 350 x 4 374 mm🔖
ConfigurationL
Speed (rpm)750
Fuel TypeNatural Gas
TechnologySpark-Ignited Gas (SG)
Displacement l per cyl36.3
📄
Download datasheet (PDF) (125 KB)
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