Wärtsilä 34DF

Advanced dual-fuel technology & efficiency, used for both main engine and generating set applications

The Wärtsilä 34DF is manufactured in configurations from 6L to 16V, giving 500 kW per cylinder and a total maximum mechanical output of 8000 kW. The engine speed is 750 rpm.

Based on the well proven and reliable Wärtsilä 32 diesel engine introduced in the mid-1990s, fuel flexibility means the engine can be optimized for constant speed generating sets, as well as variable speed mechanical drives, for main engine applications.


    Fuel flexibility

    The Wärtsilä dual fuel engine capability enables ships to be operated on either conventional liquid marine fuels (LFO, HFO or liquid bio fuel) or LNG. The switch between fuels can be made seamlessly without loss of power or speed. Such fuel flexibility enables compliance with emission regulations in controlled areas, while giving operators the option of determining the fuel according to cost and availability.

    When operating in gas mode, the Wärtsilä 34DF engine is already compliant with IMO Tier III regulations without any secondary exhaust gas purification systems. Also, when fuelled by gas, the SOx and CO2 emissions are notably reduced and smokeless operation is attained.

    In liquid fuel oil mode, the Wärtsilä dual fuel engines are fully compliant with the IMO Tier II exhaust emissions regulations set out in Annex VI of the MARPOL 73/78 convention. The engine is able to operate efficiently and economically on low sulphur fuels (<0.1% S), making it suitable for operation in emission-controlled areas.

    The Wärtsilä 34DF has also obtained certification of emission standard compliance from the United States Environmental Protection Agency (EPA), which further endorses the environmental compliance of this engine.

    Technical data
    Wärtsilä 34DF IMO Tier III, EPA T3
    Cylinder bore 340 mm Fuel specification:
    Piston stroke 400 mm Fuel oil 700 cSt/50°C
    Cylinder output 500 kW/cyl 7200 sR1/100°F
    Speed 750 rpm ISO 8217
    Mean effective pressure 22.0 bar category ISO-F-DMX, DMA & DMB
    Piston speed 10.0 m/s BSEC 7530 kJ/kWh at ISO cond.
    BSGC 7440kJ/kWh at ISO cond.

    W&#228;rtsil&#228; 34DF engine dimensions
    Dimensions (mm) and weights (tonnes)
    Engine type A B C D F Weight
    6L34DF 5335 2550 2380 2345 1155 35
    8L34DF 6315 2550 2295 2345 1155 44
    9L34DF 6869 2550 2610 2345 1155 49
    12V34DF 6865 2435 2900 2120 1210 61
    16V34DF 7905 2570 3325 2120 1210 77

    Rated power
    Engine type kW
    6L34DF 3 000
    8L34DF 4 000
    9L34DF 4 500
    12V34DF 6 000
    16V34DF 8 000


    The Wärtsilä 34DF is the ideal choice for main power source in a vast range of applications, for instance offshore support vessels and platforms, small LNG carriers, ferries & tugs.

    Besides serving as mechanical-drive or diesel/gas-electric main engine, the Wärtsilä 34DF is also a perfect fit as auxiliary generating set installed alongside Wärtsilä 46DF or 50DF main propulsion machinery. Thus completing the multi-fuel engine room concept.
    Methane Number

    Wärtsilä Methane Number Calculator

    We have developed this tool for ship owners and operators to calculate the Methane Number of the fuel gas.
    The calculation result indicates whether or not the given gas quality is suitable for use in Wärtsilä dual-fuel engines.

    Methane CH4
    Iso-butane (2-Methylpropane)i-C4H10
    Iso-pentane (2-Methylbutane)i-C5H12
    Neo-pentane (2,2-Dimethylpropane) neo-C5H12
    Mix-hexaneMix C6H14
    Mix-heptaneMix C7H16
    Carbondioxide C02
    Nitrogen N2
    Hydrogen sulfideH2S
    Total mol%
    Wärtsilä Methane number (WMN)
    Propane Knock Index (PKI)
    The calculation tool is owned by Wärtsilä and is made for customer use and is for guidance only. Changes in the tool is reserved at any time.


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