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Wärtsilä
9LW31DF-GS-50Hz
The Wärtsilä 9LW31DF‑GS‑50Hz is a 9‑cylinder, L‑configured dual‑fuel (LNG/HFO) auxiliary engine delivering ~2 520 kW (diesel) and ~2 394 kW electrical output at 750 rpm for shipboard power generation.
2520.0 kW
Power
Engine Specifications
9
Cylinders
310 mm
Bore
430 mm
Stroke
4-stroke
Stroke Type
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
power kw
2520
rpm
750
fuel type
LNG/HFO (Dual-Fuel)
configuration
L
genset kw
2394
genset kva
2992
frequency hz
50
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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
Cylinder liner wear and scuffing (general 4-stroke diesel pattern, not W31-specific): Exacerbated by inadequate lubrication oil film, excessive cylinder tempera
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
Scavenge space deposit accumulation and fire risk (class-wide diesel phenomenon): Carbonized lube oil and unburnt fuel residues accumulate in scavenge space. Ex
Type-general inspection and maintenance points for this equipment category — not model-specific.
Suppliers & Spare Parts
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Equipment Model #125022
· ✓ still in production
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We know 12+ companies supplying Wärtsilä 9LW31DF-GS-50HZ. Tell us what you need — we obtain the quotations for you.
NAVTRONIC A/S · NorwayRadio Holland Group BV · NetherlandsSea Link Distriparks Pvt LtdSea-Com · JapanAkil Corporation · IndiaBaltic Spares Service Sp. z o.o. · Poland
+6 more
Wer liefert dieses Teil? 197 Betriebe im Verzeichnis · 15 aus Herstellerlisten
Chongqing Chuanqing Marine Power Equipment Co., Ltd.
Chongqing, China
FM-Power Serviços e Peças
Rio de Janeiro, Brazil
MARE Supply & Services
Haarlem, Netherlands
Marine Ecology Equipment OÜ
Tallinn, Estonia
OSM International
Miami, United States
Qinhuangdao Hy Marine Machinery Equipment Co., Ltd.
Qinhuangdao, China
World Marine Automation System
Busan, South Korea
2K Shipping & Trading Ltd
Kayaboyun, Turkey
A & D Sales Ltd
Skelmersdale, United Kingdom
ALME MARINE SA
Greece
ANEXUS
Barcelona, Spain
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Global Services (Europe) Ltd · United KingdomA. Nobel en Zn. - Filtration & Separation B.V. (Headquarters) · NetherlandsBaltic Spares Service Ltd · PolandCimar S.R.L. Industrial and Maritime Consulting Trading and Services · ItalyDallaserra Ridderkerk Spares BV · NetherlandsGulf Marine Tech (GMT) · United Arab EmiratesHARBOR EAGLE GEMICILIK ANONIM SIRKETI · TurkeyHyosung Marine Co., Ltd. · South KoreaMSHS Pacific Power Group · United StatesMabax Global Limited · NigeriaPK OEM Parts B.V. · NetherlandsS KELEPOURAS & CO · Greece