There are two types of rolling contact bearings: ball bearings and roller bearings. Ball bearings, as the name suggests, use balls as the rolling element while roller bearings use rollers.

Ball bearings can be divided into two groups: radial ball bearings and angular contact ball bearings . Radial ball bearings support primarily radial loads which act perpendicular to the bearing axis. Angular contact ball bearings support both radial and thrust loads which act parallel to the bearing axis.

how radial loads act perpendicular to the bearing axis while thrust loads act parallel to the bearing axis. In some instances there are two radial loads acting on a bearing. The Pythagorean Theorem is used to calculate the resultant radial load. The radial load may be located between the two bearings . The simple beam formula can be used to calculate the individual load on each bearing. It can be shown that the bearing located closer to the load supports the greater portion of the load. The load may also be located overhanging the two bearings. In this case, the beam formula will show that the bearing located closer to the load actually supports more than the load itself.