The difference in pressure between the suction and discharge branches of a pumping system, which is required to produce a flow of liquid.

The twisting of a shaft or any other structure about an axis in a cyclical manner due to a varying applied torque.

The strain set up onto a member which is twisted without bending.

The tendency of a container to pivot on its bottom edge and eventually to overturn when subject to extreme rolling motions of the ship.

The introduction of inert gas into a tank which is already in the inert condition with the object of raising the tank pressure to prevent any ingress of air.

The operation of completing the loading of a tank to a required ullage.

Sawn wood or lumber, cants, logs, poles and all other types of timber in loose or packaged forms.

Gross tonnage, under vessel measurement rules of various nations.

The variation permitted in a dimensional size, position, form, etc., of a component.

A barrier placed along the edge of a walking surface to prevent personnel from placing their feet over the edge of an elevated walking surface.

A light, strong, corrosion resistant metal which is used as the plate material in plate-type heat exchangers. It is also used as an alloy element in various special steels.

A ductile, malleable metal, resistant to corrosion. It can be used as a coating for steel and also in various alloys.

A special load line assigned to ships complying with certain conditions related to their construction set out in the International Convention on Load Lines...

A cargo of timber carried on an uncovered part of freeboard or the superstructure deck. The term does not include wood pulp or similar cargo.

An arm, attached to rudderstock, which turns the rudder.

An air test or other medium test carried out to demonstrate the tightness of the structure.

Thrusters are used to allow ships to be more independent from tugs, give them more manoeuvrability for special tasks, and in some cases give them a “take home” capability.

All components and systems necessary to supply the DP system with thrust force and thruster direction.

A short length of shaft with flanges at either end and a thrust collar in the centre.

The product of the propeller thrust and speed of vessel advance.