Compression Spring terms:

 

[caption id="attachment_2242" align="aligncenter" width="300"] stainless steel compression springs[/caption]

Compression Spring terms:

Active Coils- the coils that deflect when a compression spring is under load.
Buckling- the point at which a compression spring bends when a long, slender compression spring is under load.
Closed Ends- the point at the end of a compression spring where the end coils touch.
Closed and Ground End- same as closed ends except the ends of the compression spring is ground flat.
Closed Wound- the state in which a compression spring is coiled with all adjacent coils touching.
Deflection- motion of the compression spring when placed under load.
Elastic limit- the maximum amount that compression spring wire can be placed under load before the compression spring sets.
Endurance limit- the maximum compression spring material can operate indefinitely without failure during minimum stress.
Free length- the overall length of a compression spring under no load.
Frequency- the lowest rate of vibration for a compression spring while ends are held stationary.
Hysteresis- the amount of energy lost in a compression spring during cycling.
Mean diameter- the outside diameter of a compression spring minus one wire diameter.
Modulus- the coefficient in stiffness of a compression spring.
Open ends- the same pitch throughout a compression spring
Open ends ground- same as open ends but with ground ends
Permanent set- when a compression spring is deflected beyond its elastic limit as does not return to its original position.
Pitch- the distance of one wire mean to the adjacent wire mean in a compression spring.
Rate- the change in compression spring load between units of measure.
Set removal- compressing a compression spring to its solid height to achieve desired length and reduce elastic limit.
Set- permanent distortion caused by compressing a compression spring beyond its elastic limit.
Slenderness ration- ratio of length to mean diameter in a compression spring.
Solid height- the position of a compression spring when compressed, all adjacent coils are touching.
Spring Index- the ratio of mean coil diameter to wire diameter in a compression spring.
Squareness- the angular difference between a compression spring axis and plane ends.
Total coils- the number of active coils plus the inactive compression spring coils.