What is the Purpose of a Thrust Bearing

A thrust bearing is generally composed of two or more thrust washers and several rolling elements. Generally, the thrust washer is divided into shaft piece and base piece, and the rolling element is commonly composed of iron or copper holder group. 

Steel thrust ball bearings (TBB bearing) are the most common type of such bearings.

The aim of thrust bearing is to support the bearing. But this is only one of its functions.

The essence of the support is to bear the radial load, or to fix the shaft, that is, to fix the shaft so that it can only rotate while its axial and radial movement is controlled. The motor requires that the shaft only rotate but not move. Therefore, the shaft may move in any direction without bearings and the motor cannot work.

Theoretically speaking, the bearing can not realize transmission, and it can affect the transmission effect. In order to reduce the influence, the bearing of the high-speed shaft must be well lubricated. Some bearings have been lubricated which is called pre-lubricated bearings. Most bearings need to work with lubricant. At high speed, friction will not only increase energy consumption but also damage the bearing easily. And the argument that sliding friction is converted into rolling friction is one-sided because there is sliding bearing.