Deep groove ball bearings are mainly used to withstand pure radial loads and can also withstand radial and axial loads. When it is only subjected to a pure radial load, the contact angle is zero. When the deep groove ball bearing has a large radial clearance, it has the performance of an angular contact bearing and can withstand a large axial load. The deep groove ball bearing has a small friction coefficient and a high limit speed. Especially in high-speed running conditions with large axial loads, deep groove ball bearings are superior to thrust ball bearings.