#Salient Features of External Circlips
Spring take up devices to compensate for developed looseness and loss of tension between components of an assembly. It is a well known fact that the initial tension in a bolt or screw is reduced by its gradual stretch, the slight wearing-down of the contracting surface or the breakdown of rust, scale or protective paint, enamel, etc., finishes. The use of a Spring Washer under the nut or bolt head exerts an axial force during this period of initial looseness, preventing the tightening pressure diminishing below a danger level, i.e. the point at which the nut and bolt can easily rotate backwards.
Hardened thrust bearing to facilitate assembly of bolted fastenings, by decreasing the frictional resistance between the bolted surfaces and the bearing face of bolt head or nut.
