Ball bearing is also called deep groove ball bearing, it is one of the most common type of rolling bearing that the steel ball is installed inside a retainer between the inner steel ring and the outer steel ring to reduce the friction force in the process of power transmission and improve the transmission efficiency of mechanical power. There are open type, with shields or rubber seals for ball bearing. Ball bearing has the characteristics of fast speed, low friction, simple structure and convenient use. It is the most widely used in industries. Usually, ball bearing is mainly used to support radial load in application, but it is also commonly used to support axial load. The rotational friction resistance of ball bearing is smaller than other kinds of bearings, so the temperature generated by friction will be relatively low at the same speed. Therefore, ball bearing are widely used in high-speed equipment。