Bearing life

Under certain loads, the number of rotations or hours that a bearing experiences before pitting corrosion is called bearing life.

The life of a rolling bearing is defined by the number of rotations (or hours of work at a certain speed). Bearings within this life should suffer from initial fatigue damage (spalling or defect) on any bearing ring or rolling element. However, no matter in laboratory test or in actual use, it is obvious that the actual life of bearings with the same appearance under the same working conditions is quite different. In addition, there are several different definitions of bearing "life", one of which is the so-called "working life", which means that the actual life of a bearing before damage is caused by wear, damage is usually not caused by fatigue, but by wear, corrosion, seal damage and other reasons.

In order to determine the standard of bearing life, bearing life and reliability are linked.

Because of the difference of manufacturing accuracy and material uniformity, even if the same material and the same size of the same batch of bearings are used under the same working conditions, their life is different. If the statistical life is 1 unit, the longest relative life is 4 units, the shortest is 0.1-0.2 units, and the ratio of longest to shortest life is 20-40 times. 90% of bearings do not produce pitting corrosion. The number of rotations or hours experienced is called rated life of bearings.