Deep groove ball bearing is the most commonly used rolling bearing. Its structure is simple and easy to use. It is mainly used to bear radial load, but when the radial clearance of the bearing is increased, it has certain performance of angular contact ball bearing and can bear combined radial and axial load. When the speed is high and it is not suitable to use thrust ball bearing, it can also be used to bear pure axial load. Compared with other types of deep groove ball bearing with the same size, the friction coefficient of this kind of bearing is small and the limit speed is high. But it is not resistant to impact and is not suitable to bear heavy load. After the deep groove ball bearing is installed on the shaft, the axial displacement of the shaft or the shell can be limited within the axial clearance range of the bearing, so the axial positioning can be made in both directions. In addition, this kind of bearing also has a certain ability of centering. When it is 2 ′～ 10 ′ inclined to the shell hole, it can still work normally, but has a certain impact on the bearing life.