Broström tanker propelled by Rolls-Royce pulling azimuth thrusters

14 June 2006

Broström tanker

Bro Deliverer is the first of a series of four combined product/chemical tankers which break new ground in propulsion systems. They will all be propelled, manoeuvred and moored using Rolls-Royce equipment.

The D-class Broström vessels are designed to meet the present and future requirements of the oil and chemical industry, both in terms of the volumes and types of cargo to be carried, and in providing safe, low environmental impact and economical transport. Broström operates worldwide, has its headquarters in Sweden, and is one of the leading logistics companies for the oil and chemical industries, focusing on industrial product and chemical tanker shipping and marine services.

Since the vessels will often be manoeuvring in port, operating in shipping lanes with heavy traffic, and need to meet future regulations and expectations, a high level of manoeuvrability and propulsion redundancy has been specified.

Rolls-Royce will supply each vessel with two Azipull thrusters rated at 2,380kW each for main propulsion. The AZP120 units with pulling propellers are the first Azipull thrusters to go into service in tanker propulsion. They provide propulsion and steering, and are supplemented by a TT1850 tunnel bow thruster of 1,000kW. Loaded service speed is about 13 knots

By using two azimuth thrusters for propulsion, each with its own medium speed main engine, independent steering and separate fuel systems for each engine, a high level of propulsion redundancy has been achieved, and Bro Deliverer has RP class notation from DNV and Clean Design class.

Broström’s D-class tankers have a deadweight of about 14,500dwt on a draught of 8m, an overall length of 146.8m, a beam of 22m and 14 tanks with a capacity of 18,556m3 when 98% full. They are built at Jinling shipyard in China.

In addition to the propulsion equipment, Rolls-Royce is supplying deck machinery for all these Broström D-class tankers. Each has a total of eight winches; two of which are combined anchoring and mooring winches, with a 10 tonne line pull and a cable lifter for 58mm chain. The others are purely mooring winches. All the units have direct drive using low pressure hydraulic motors.

Azipull thrusters were first applied to propulsion of 22 knot double ended ferries. A totally different market segment opened up with the successful installation of Azipull units in an offshore supply vessel. Since then, a large number of offshore vessels have been ordered with Azipull thrusters to take advantage of the high efficiency, good steering and low noise and vibration levels that can be achieved with this type of propulsion.

Now the product tanker market has recognised the advantages of Azipull thrusters. Bro Deliverer is the first into service by a small margin, and a Bergen Tankers product tanker to an Rolls-Royce design, equipped with two AZP100 units, is currently on sea trials.