The thrust ball bearings are classified into two kinds: unidirectional thrust bearing and bidirectional thrust bearing. The former can bear the axial force in one direction and the latter can bear he axial forces in two directions. Both unidirectional and bidirectional thrust ball bearings cannot bear any radial force.Ball bearings, or deep-groove bearings, extend the working life of equipment by enabling wheels, pulleys, and other rotating parts to reduce friction and move smoothly. Ball bearings have a series of round balls encased in a housing and support high axial or low-to-moderate radial loads.

Thrust ball bearings are classified into those with flat seats or aligning seats depending on the shape of the outer ring seat (housing washer). They can sustain axial loads but no radial loads. For Single-Direction Thrust Ball Bearings, pressed steel cages and machined brass cages are usually used The cages in Double- Direction Thrust Ball Bearings are the same as those in Single-Direction Thrust Ball Bearings of the same diameter series.