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Wärtsilä

Wärtsilä 31DF

Der Wärtsilä 31DF hält den Guinness-Weltrekord als effizientester 4-Takt-Dieselmotor (im Diesel-Modus). Im Gas-Modus (LNG) erreicht er IMO Tier III ohne Abgasnachbehandlung. Standard auf LNG-betriebenen Fähren, Offshore-Versorgern und zunehmend auf Kreuzfahrtschiffen. Multi-Fuel-fähig: Diesel, LNG, Methanol (in Entwicklung), Ammoniak (Zukunft).

2,610-10,440 kW (6-16V)
Capacity
LNG (Dual-Fuel) / HFO / MGO
Medium

Engine Specifications

6L, 8L, 10V, 12V, 14V, 16V
Cylinders
310 mm
Bore
430 mm
Stroke

Components & Design

Component data being added…

Technical Data

Cylinder power 610 kW/cyl (diesel)
Mean effective pressure (BMEP) 30 bar
SFOC (diesel) 167.7 g/kWh (optimal point)
Weight (8V31) ~57.1 tonnes (dry, diesel)
Weight (16V31) ~89–92.5 tonnes (dry, diesel)
Piston speed 10.75 m/s
Turbocharging Two-stage turbocharging with intercooling
Fuel injection Common rail direct injection
Valve layout 2 inlet, 2 exhaust valves per cylinder
type 4-Stroke Dual-Fuel Medium-Speed Engine (Otto Cycle in Gas Mode)
sfoc g kwh 165
tier IMO Tier III (gas mode)
variant count approx 6
period start year 2015
drive type Gearbox + CPP or Generator
construction Trunk piston, DF gas admission, pre-chamber ignition

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Common failures & inspection points

Low-load operation: Poor combustion, carbon deposit accumulation in cylinders, turbocharger fouling, economizer fouling. Wärtsilä offers Slow Steaming Upgrade K
chiefengineerlog.com/2022/08/22/wha...
Cylinder liner wear and scuffing (general 4-stroke diesel pattern, not W31-specific): Exacerbated by inadequate lubrication oil film, excessive cylinder tempera
www.marineinsight.com/main-engine/m...
Fuel injection system: Common rail system generally robust; however, HP fuel pump overhaul intervals are extended to 24,000 hrs (vs. 12,000 in prior-gen engines
www.wartsila.com/insights/article/c...
Scavenge space deposit accumulation and fire risk (class-wide diesel phenomenon): Carbonized lube oil and unburnt fuel residues accumulate in scavenge space. Ex
marinersspace.com/complete-guide-to...

Type-general inspection and maintenance points for this equipment category — not model-specific.

Service & Maintenance

Spark plug: 2,000-4,000 hrs. Gas valve: 6,000-8,000 hrs. Piston: 18,000-24,000 hrs. Standard 4-Stroke intervals für restliche Komponenten.

Suppliers & Spare Parts

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Replacement Parts

Wärtsilä global. Spark plugs: an Bord vorhalten (10+ Sätze).

Manuals

  • operating
    Wärtsilä 31 Operating Manual
  • maintenance
    Wärtsilä 31 Maintenance Manual
  • spare_parts
    Wärtsilä 31 Spare Parts Catalogue
  • installation
    Wärtsilä 31 Engine Installation Manual
Equipment Model #38021 · ✓ still in production