Deep groove ball bearings are non-separable and require little attention or maintenance in service, capable of operating at high speeds and are widely used radial bearings. The inner and outer ring of single row deep groove ball bearings have a deep groove raceway. The bearings are mainly used to carry radial loads and a part of axial loads in two directions. This kind of bearing can carry much heavy axial loads after the increase of radial clearance, thus, it can take the place of high speed angular contact ball bearings. Deep groove ball bearing have various types in structure, besides open type bearings, shield or seals at both side can also be provided.