Main Engine 4-Stroke · Main Engines (4-Stroke)
This engine is commonly found in large commercial vessels operating in international shipping lanes, where it provides reliable and efficient propulsion. The Wärtsilä 12W31DF, a dual-fuel engine capable of running on LNG, HFO, or MGO, delivers a power output of 7320 kW at 750 rpm. Its L configuration with 12 cylinders, a bore of 310 mm, and a stroke of 430 mm ensures robust performance. The engine features two-stage turbocharging with intercooling and common rail direct injection for optimal fuel efficiency and reduced emissions. Certified to Tier III standards, it operates efficiently across a range of fuels, enhancing operational flexibility. However, common issues such as poor combustion at low loads, carbon deposit accumulation, and crankcase oil mist build-up can arise, necessitating regular maintenance and monitoring. Wärtsilä offers upgrades like the Slow Steaming Upgrade Kit to mitigate low-load operation issues, ensuring continuous reliable operation.
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| oil_change | 400-600 hours |
|---|---|
| fuel_filter_replacement | 1000-1500 hours |
| air_filter_replacement | 500-1000 hours |
| turbocharger_inspection | 2000-3000 hours |
| cylinder_head_overhaul | 10000-15000 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 | 0.1-0.5 mm wear limit |
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 operation and maintenance of dual-fuel systems, and inspect for signs of wear or damage on critical components
Estimated lifetime: 30000-50000 hours
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