meaning of washer

Washer - in this blog is not washching-machine, it is a thin plate (typically disk-shaped) with a hole (typically in the middle) that is normally used to distribute the load of a threaded fastener. Other uses are as a spacer,wear pad, preload indicating device, and locking device.It could be made of various materials. It usually made of metal because it is the most strength, to prevent the loss of pre-load. Another washer is rubber or fiber glass ever use in tap to stop the flow of liquid or gas. ** Usually washer have outer diameter about twice their inside diameter.