Wärtsilä Transverse Thrusters

Wärtsilä transverse thrusters WTT

Transverse thrusters provide a side force that supports mooring operations and station keeping. Wärtsilä WTTs deliver superior hydrodynamic performance for high thrust - diameter ratio.

Wärtsilä transverse/tunnel thrusters WTT

Transverse thrusters, also known as tunnel thrusters, bow thrusters or stern thrusters, provide a side force, or transverse thrust, to support mooring operations or station keeping.

Wärtsilä WTTs have compact dimensions, yet they deliver high thrust. They are available in a range from 400 kW to 5500 kW and are an excellent choice for ships such as:

merchant vessels
cruise vessels
offshore support vessels
offshore construction vessels.

In auxiliary applications, transverse thrusters support the mooring or harbour operations of merchant cargo vessels.

When applied in Dynamic Positioning systems, transverse thrusters extend the DP capability of, for example, offshore supply vessels.

Key benefits

Superior hydrodynamic performance for high thrust - diameter ratio
Robust, reliable and maintenance friendly design
Easy installation; high level of integration
Maintenance friendly design
Wärtsilä ProTouch controls with ergonomic levers and intuitive touch screen displays or push-button panels

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Application
Merchant
Options
Technical info

Application

Wärtsilä transverse thrusters are available in a range from 400 kW to 5500 kW for applications in numerous types of ships, including merchant vessels, cruise vessels, offshore support vessels, and offshore construction vessels.
Transverse thrusters, also known as bow thrusters, stern thrusters or tunnel thrusters, provide a side force, or transverse thrust, to support mooring operations or station keeping.
Transverse thrusters are available for auxiliary or AUX usage, which is mostly applicable with merchant vessels to support harbour manoeuvring and mooring operations. Where the transverse thruster is part of a dynamic positioning (DP) system, the rating for DP use applies.

Merchant

Cost per kW - 15% reduced cost (CAPEX) per kW*
Environmental compliance - Compatibility with environmentally acceptable lubricants (EAL) - Ensures compliance with environmental regulations such as US EPA VGP2013 and DNV CLEAN DESIGN
Smaller footprint - Integrated hydraulics and fine filtration ensures longer lifetime for gear, bearings and other rotating components
User centric interface - ProTouch control system - bus connections for simplified installation and integration with other equipment control, monitoring and alarm systems
Global support - Service and delivery available when and where you need it
Reliability - Robust design for reliable operations in demanding environments and low operational cost
Experience - over 1,250 Wärtsilä Transverse Thrusters delivered or on order in the Merchant segment, of a total of 3,250 units
Flexible Options – WTT are available in CPP and FPP giving you the option to select the right system to meet your needs.

*Compared to a standard Wärtsilä Transverse Thruster with the same propeller diameter. The improvement may vary depending on configuration, fuel, vessel and currency.

Options

Controllable or fixed pitch propeller upto WTT-40 type; CP propeller for WTT-45 and CT3500 types
Manoeuvring (AUX) or Dynamic Positioning (DP) application
Redundant pumps and/or lubrication filters
Compatible with environmentally acceptable lubricant (EAL) for EPA VGP 2013 compliance or CLEAN notation compliance
Face type seal or Air barrier seal for WTT-21 and up
Tailor-made tunnel with tunnel ends cut according to hull form and additional circular or longitudinal stiffeners
L-drive with intermediate shaft and separate E-motor foundation
De-mountable, low noise, horizontal drive variants
Package with electric motor and starter

Technical info

Range and dimensions

Type	Electrical Frequency (Hz)	Input Speed (rpm)	Maximum Power¹		Propeller Diameter (D) (mm)	Length (L) (mm)	Weight² (kg)
			Manoeuvring AUX/Merchant (kW)	Dynamic Positiong DP (kW)
CT/FT125 H	60 50	1780 1480	610 510	600 500	1250	1550	2800
CT/FT150 H	60 50	1780 1480	880 735	780 650	1500	1800	4150
WTT-11	60 50	1180 980	1100 1100	1000 1000	1750	1970	5750
WTT-14	60 50	1180 980	1450 1450	1300 1300	2000	2195	8000
WTT-16	60 50	1180 980	1650 1650	1490 1475	2200	2115	10100
WTT-21	60 50	1180 980	2100 2200	1825 1825	2400	2275	12000
WTT-24	60 50	880 980	2600 2600	2150 2150	2600	2390	13900
WTT-28	60 50	880 735	3000 2800	2400 2400	2800	2970	20200
WTT-32	60 50	710 735	3300 3300	2800 2800	3000	3285	25400
WTT-36	60 50	710 735	3600 3600	3200 3200	3200/3300	3350	29400/29700
WTT-40	60 50	710 735	4000 4000	3600 3600	3400	3520	32800
WTT-45	60 50	710 735	4800 4800	4050 4050	3600	3800	40400
CT3500	60 50	590 590	5500 5500	5000 5000	4000	4300	63700

¹ Maximum power level is valid for uni-directional rotation. Depending on propeller type and class society, lower power levels may apply.
² Version with CP propeller including a standard tunnel with E-motor support., excluding E-motor.

Weights and dimensions

Power range

Did you know? The grid matters

Discover Elogrid by Wärtsilä, a unique solution for tunnel thrusters on ships, optimised and customised to add thrust force and save fuel in transit mode. This special grid solves the big problem associated with a conventional grid. Like any grid, it will save fuel in transit mode, but the ship will not suffer a loss of thrust force. On the contrary, this special grid will increase the thrust!
Learn more

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