Wärtsilä Steerable Thrusters

The Wärtsilä Steerable Thruster (WST) has a light ice class capability and can be combined with high-speed engines up to 1800 rpm. Two nozzle types can be selected depending on customer requirements: a bollard pull nozzle or a nozzle optimised for free-sailing.

The Wärtsilä Steerable Thruster (WST) series replaces the Wärtsilä LCT series for tugs and similar vessel types. For certain executions, such as L-drive layouts, the LCT type of thrusters can be offered on request.

    • The Wärtsilä Steerable Thruster (WST) series is intended for tug or offshore support vessel application and river-sea going vessels.

    Example configurations


    • FP propeller
    • Bollard-pull nozzle
    • Diesel-mechanic drive
    • Slipping clutch
    • PTO driven steering/lubrication systems

    Platform Supply Vessel (PSV)

    • FP propeller
    • Free-sailing nozzle
    • Diesel-electric drive
    • Electric steering
    • Electric lubrication system
    Key benefits
    • Superior hydrodynamic performance for high bollard pull or maximum propulsion efficiency.
    • Compatible with high speed engines (up to 1800 rpm).
    • Compact dimensions with a high level of integration.
    • Robust design for reliable operations.
    • Maintenance friendly design to minimize downtime.
    • Reduced number of external connections and field bus technology for ease of installation.
    • Wärtsilä ProTouch controls with ergonomic levers and intuitive touch screen displays.
    Technical Info
    WST table 1
    Wärtsilä Steerable Thrusters
    WST table 2
    WST compact series
    • Diesel-mechanical Z-drive configuration compatible with engine speeds ranging from 720 rpm to 1800 rpm (intermediate ratios available on request).
    • Integrated power take off for steering, lubrication, clutch and pitch hydraulics (DM variant).
    • Diesel-electric Z-drive configuration with electric steering and auxiliary systems.
    • 2 propeller diameters per size (3 diameters for WST-14).
    • FP propeller and integrated medium duty clutch (slipping range up to 50% engine rpm) or CP propeller with dry on/off clutch.
    • Two nozzle types: optimized for bollard pull or free sailing (FP propeller only).
    • Finnish-Swedish (Baltic) ice class up to 1B, Russian (RMRS) ice class up to Ice-3 or equivalent Russian river register (RRR) ice class.
    • EPA VGP 2013 compliance.
    • Multiple installation options: bolt-in, weld-in, can-mounted or split installation.

    Related press releases


    9 November 2015
    • Twentyfour7. article

    Turn this way

    An innovative new Wärtsilä thruster offers captains manoeuvrability and, thanks to its lean and compact...


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