Follett 00161356

WASHER RETAINER

A retainer is a mechanism that positions, as a device, frame, or groove that restrains, holds in place, or guides.  A retainer may be also be a clip, bracket, or similar component that prevents a part within a machine from moving.

A washer is a thin plate (typically disk-shaped, but sometimes square) with a hole (typically in the middle) that is normally used to distribute the load of a threaded fastener, such as a bolt or nut. Other uses are as a spacer, spring (Belleville washer, wave washer), wear pad, preload indicating device, locking device, and to reduce vibration (rubber washer). Spring washers, which have axial flexibility are used to prevent fastening or loosening due to vibrations. Locking (lock) washers prevent fastening or loosening by preventing unscrewing rotation of the fastening device.