# COMPRESSION SPRING

A spring, usually a coil spring, which resists a force tending to compress it.

## Related Terms

### COMPRESSOR

A device which converts mechanical force and motion into pneumatic flow power.

### HEAVE

The oscillatory vertical rise and fall, due to the entire hull being lifted by the force of the sea. Also called HEAVING

### FRICTION

The resisting force encountered at the common boundary between two bodies when, under the action of an external force, one body, moves or tends to move relative to the surface of the other.

### PUMP

A device which converts mechanical force and motion into hydraulic fluid power.

### LIQUID

Any substance that flows readily or changes in response to the smallest influence. More generally, any substance in which the force required to produce a deformation depends on the rate of deformation rather than on the magnitude of the deformation.

### HEELING ERROR INSTRUMENT

Heeling adjuster. Also called VERTICAL FORCE INSTRUMENT

### POISE

A measure of viscosity (absolute viscosity) numerically equal to the force required to move a plane surface of one square centimeter per second when the surfaces are separated by a layer of fluid one centimeter in thickness. It is the ratio of the shearing stress to the shear rate of a fluid and is expressed in dyne seconds per square centimeter (DYNE SEC/CM2); 1 centipoise equals .01 poise.

### KINEMATIC VISCOSITY

The time required for a fixed amount of an oil to flow through a capillary tube under the force of gravity. The unit of kinematic viscosity is the stoke or centistoke (1/100 of a stoke). Kinematic viscosity may be defined as the quotient of the absolute viscosity in centipoises divided by the specific gravity of a fluid, both at the same temperature Centipoises / Specific Gravity = Centistokes .

### MAGNETIC BEARING

A type of bearing in which the force that separates the relatively moving surfaces is produced be a magnetic field.

### SOLID

Any substance having a definite shape which it does not readily relinquish. More generally, any substance in which the force required to produce a deformation depends upon the magnitude of the deformation rather than upon the rate of deformation.