Main Engine 4-Stroke · Main Engines (4-Stroke)
The crew and engineers on board maritime vessels rely on reliable and efficient engines to ensure smooth operations and comply with environmental regulations. One such engine is the Wärtsilä 8W31DF, designed for optimal performance and efficiency. This engine features a Tier III Dual-Fuel technology that can run on diesel (HFO, MDO, LFO) or dual-fuel LNG/Diesel, providing flexibility and reduced emissions. With an output of 4880 kW at 750 rpm, it is well-suited for a range of marine applications. The engine’s robust design includes common rail direct injection and two-stage turbocharging with intercooling, ensuring efficient combustion and high power density. Each cylinder delivers 610 kW in diesel mode, and the engine operates at a mean effective pressure of 30 bar. It weighs approximately 57.1 tonnes (dry, diesel) and features a bore of 310 mm and a stroke of 430 mm. Regular maintenance and inspections, such as addressing low-load operation issues and monitoring cylinder liner wear, are essential for maintaining its performance and longevity.
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| item | every 1000-2000 hours for routine maintenance, with major overhauls typically required every 20,000-30,000 hours |
|---|
| cylinder_liner | 0.5-1.0 mm wear limit |
|---|---|
| piston_ring | 0.5-1.0 mm wear limit |
| exhaust_valve | 0.5-1.0 mm wear limit |
| fuel_injector | 10-20% reduction in flow rate |
Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.
Class surveyors typically check for compliance with Tier III emissions regulations, verify proper maintenance and record-keeping, and inspect critical components for wear and condition
Estimated lifetime: 40,000-60,000 hours before major overhaul
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