What is a thrust washer?

A thrust washer is a type of washer used in mechanical devices to prevent axial motion or friction between rotating parts. It typically consists of a flat metal or plastic disk with a central hole that fits over a shaft or bolt. The washer is placed between two rotating parts, such as a gear and a shaft, to reduce friction and wear on the surface of the parts. Thrust washers can also be designed to have a specific thickness or shape to provide additional support or alignment for the parts they are placed between. They are commonly used in engines, transmissions, and other mechanical systems to help distribute loads and reduce friction and wear.