Bearings are components that fix and reduce the coefficient of friction of the load during mechanical transmission. It can also be said that when other parts move relative to each other on the shaft, the mechanism for reducing the coefficient of friction during power transmission and maintaining the center position of the shaft is fixed. Bearings are a very important part of contemporary machinery. Its main function is to support the mechanical rotating body to reduce the mechanical load friction coefficient of the equipment during the transmission process. According to the friction properties of moving components, bearings can be divided into rolling bearings and sliding bearings.