Lines obtained by cutting the hull surface with longitudinal planes parallel to the ship’s centre line.

Ropes, wire ropes, lashings, masts, booms, etc.

The end joint between two plates or other members which meet end to end. Typically a butt joint is used to describe the welded connection between two plates in the transverse direction.

The movement of an oil rig, drilling platform, etc., from one position to another.

A weld between the edges of two metal plates, which meet but do not overlap.

Copper bars fitted at the back of the main switchboard as part of the distribution system. A.C. generators fed to the bus bars and circuit breakers are used to draw off the supply.

A stabiliser system designed to reduce the craft wave-induced motions. Fast ferries operating in rough water require ride control systems to ensure passenger comfort.

An atomizer used in a boiler.

A relay fitted between a generator and the switchboard which will trip and disconnect the main circuit breaker in the event of a reverse current flow.

Retarded start of injection is a commonly used primary method for effective NOx emission reduction in the diesel engines and has negligible effect on fuel consumption when keeping injection duration conveniently short.

Any condition in which visibility is restricted by fog, mist, falling snow, heavy rainstorms, sandstorms or any other similar causes, (COLREG).

A deck, space, area, etc., not permitted to be entered for safety reasons.

A new thickness-measuring technique introduced by Det Norske Veritas. RTM sensor emits a spectrum of resonated sound waves which pass through the corroded steel.

A hard, brittle substance insoluble in water.

Machine supports which utilize springs or an elastomeric material to prevent the transmission of vibration to the supporting structure.

The positive range of the righting lever curve after damage, with external heeling levers taken into account.

Enclosed spaces, which provide buoyancy in addition to that required by a vessel to float. It is always considered in the assignment of freeboard to a ship.

The ship designed for handling navigation buoys and beacons, usually fitted with a deck crane and a spacious working deck. See also Aids to navigation service vessel.

The ship is equipped with a working crane designed for handling buoys and salvaging containers. It has two lifting devices, each with a heave compensator, with a capacity for buoy lifting of 125kN at a radius of 15m.

Specialized ships engaged in oceanographic research, marine exploration, offshore exploration and survey, fisheries and biological research, hydrography, mineral survey and meteorogical observations.