Andresen

At a time when many companies in the marine industry see mergers as the key to success, Brunvoll AS, continues to steer its own course. In fact, as Knut Andresen, Brunvoll's technical director said recently, acquiring a "package" of systems from a large concern may not be the best solution for shipowners anyway, because of the temptation for some companies to hide costs within the package.

Brunvoll has been designing and manufacturing thrusters for more than 37 years since it first introduced tunnel thrusters onto the Norwegian market. It continues to specialize in thrusters to this day, and has gained a worldwide reputation in that sector of the market, choosing to design and manufacture thrusters that are customized to meet the demands of individual ships, rather than low cost, off-the-shelf equipment that is poorly suited to individual shipowners' requirements.

In the cruise ship sector, one of the main reasons for increased demand for thruster capacity is the growing requirement for better position keeping capability.

Often this is because anchoring restrictions prevent the use of traditional means of maintaining a ship in position, leading to increased use of azimuthing propulsion units and larger bowthrusters.

In other sectors of the shipping industry, such as offshore supply vessels and cable layers, additional thruster capacity greatly enhances position keeping, providing a redundant propulsion capability, and reducing operating costs.

The most important factor in selecting the proper thrusters, said Andresen, is that the thruster or thrusters are matched to its operating requirement. Some ships may use their thrusters routinely, almost on a daily basis; but on board other types of vessel, although the thrusters may be rarely used, they need to be designed to a very high, demanding specification which can't be met with low cost, off- the-shelf products.

Brunvoll has also gained an enviable reputation for its retractable thrusters, which continue to be especially popular in the offshore market, particularly on shuttle tankers, cable layers and multipurpose offshore support vessels.

In keeping with the company's emphasis on innovation and on meeting specific customer requirements, Brunvoll has also developed retractable thrusters designed both for use when lowered and when retracted.

A typical application is on board a shuttle tanker, where rolling motions can cause a conventional tunnel thruster to draw air if they break the surface in bad weather, preventing them from maneuvering precisely enough to load safely at sea. This problem is overcome, however, when a retractable thruster is lowered beneath the ship.

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