ABATEMENT

An air cylinder which will slow down the speed of the piston at the end of its stroke. Prevents shock and damage to cylinders.

Escape of liquids such as water, oil, etc., out of pipes, boilers, tanks, etc., or a minor inflow of seawater into the vessel due to a damage to the hull

Seawater to flow into the vessel due to damage to its hull, or hatches awash and not properly closed

A process occurring within the impeller of a centrifugal pump when pressure at the inlet to the impeller falls below that of the vapor pressure of the liquid being pumped. The bubbles of vapor which are formed collapse with impulsive force in the higher pressure regions of the impeller. This effect can cause significant damage to the impeller surfaces and, furthermore, pumps may loose suction.

A phenomenon generated in a pipeline system when there is a change in the rate of flow of liquid from the line. Surge pressures can be dangerously high if the change of flow rate is too rapid and the resultant shock waves can damage pumping equipment and cause rupture of pipelines and associated equipment.

Permanent deformation of the bearing surfaces where the rollers (or balls) contact the races. Brinelling results from excessive load or impact on stationary bearings. It is a form of mechanical damage in which metal is displaced or upset without attrition.

Damage caused due to the presence of oxygen in the feedwater. Damage results are small pit-like holes in the metal.

The turbine casing is fitted with spring-loaded relief valves to prevent damage by excessive steam pressure at the low-pressure end if the exhaust valve is closed accidentally. Some casings on smaller turbines are fitted with a sentinel valve, which serves only to warn the operator of over-pressure of the exhaust end. A spring-loaded relic valve is needed to relieve high pressure.

Cannon balls linked with chain used to damage rigging and masts.

A padded fender to keep a vessel away from a pier or quay to prevent damage to the hull or pier