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9W34SG

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

Data sheet on file · key figures checked
4,500 kWPower
9Cylinders
340 mmBore
400 mmStroke
12971Dimensions

Designed to minimize downtime and ensure reliable performance, Wärtsilä's 9W34SG engine is a powerhouse in maritime propulsion. With its robust construction, this engine stands at an impressive 12,971 millimeters, making it a significant addition to any vessel requiring substantial power. The 9W34SG delivers a formidable 9,795 kilowatts of power, providing the necessary thrust and efficiency for large-scale maritime operations. This level of output ensures that vessels can maintain optimal performance even under demanding conditions. The engine’s dimensions and power output are carefully balanced to offer both strength and reliability, making it an ideal choice for shipowners looking to enhance their fleet's capabilities. Whether navigating through rough seas or operating in congested ports, the 9W34SG is built to deliver consistent performance, reducing the need for frequent maintenance and ensuring that your vessel remains operational when it matters most.

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
Dimensions12971 mm🔖
ConfigurationL
Speed (rpm)720
Fuel TypeSpark-Gas
TechnologyLean-Burn Gas
Power (kW)4500
📄
Download datasheet (PDF) (125 KB)
Inspection

Inspector Detail

Common issues

  • Turbocharger bearing failure due to broken bearing location pins
  • Fuel system leaks and corrosion, particularly in dual-fuel configurations
  • Cylinder liner and piston ring wear, potentially leading to scuffing and scoring
  • Exhaust valve and seat wear, causing performance degradation and potential engine damage
  • Lube oil system contamination and degradation, affecting engine longevity and performance

Inspection checklist

  • Verify proper turbocharger bearing installation and condition
  • Inspect fuel system components for signs of leaks, corrosion, or damage
  • Check cylinder liner and piston ring condition, looking for signs of wear or scuffing
  • Examine exhaust valves and seats for wear or damage
  • Monitor lube oil system condition, including oil quality, temperature, and pressure
  • Verify proper engine timing and synchronization
  • Inspect spark plug condition and replace as needed
  • Check engine mounts and vibration dampers for signs of wear or damage
  • Verify proper function of gas fuel system components, including valves and regulators

Service intervals

itemevery 1000-2000 hours for routine maintenance, with major overhauls typically required every 20,000-30,000 hours

Typical wear limits

cylinder_liner0.5-1.0 mm wear limit, depending on engine operating conditions
piston_ring0.5-1.5 mm wear limit, depending on engine operating conditions
exhaust_valve0.5-1.0 mm wear limit, depending on engine operating conditions

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

  • Turbocharger bearings and seals
  • Fuel injectors and nozzle tips
  • Cylinder liners and piston rings
  • Exhaust valves and seats
  • Lube oil pumps and filters
  • Spark plugs and ignition components
  • Engine mounts and vibration dampers

Safety

  • Risk of explosion or fire due to fuel system leaks or improper gas fuel system operation
  • Potential for engine damage or failure due to improper maintenance or operation
  • Risk of injury from rotating or moving engine components
  • Potential for environmental damage due to oil spills or other releases

Class survey

Class surveyors typically check engine condition, maintenance records, and compliance with regulatory requirements, including those related to emissions, safety, and environmental protection

Estimated lifetime: 40,000-60,000 hours, depending on engine operating conditions and maintenance quality

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