The number of revolutions or hours a bearing undergoes before pitting corrosion under a certain load is called the bearing life.
The life of a rolling bearing is defined by revolutions (or hours of work at a given speed) : the bearing within this life shall undergo initial fatigue damage (flaking or loss) on any of its bearings or rolling bodies.However, no matter in the laboratory test or in the actual use, it can be clearly seen that the appearance of the same bearing under the same working conditions, the actual life is very different.In addition, there are several different definitions of bearing "life", one of which is called "working life", which indicates that the actual life of a bearing that can be achieved before it is damaged is caused by wear and tear, which is usually not caused by fatigue, but by wear, corrosion, seal damage, etc.
In order to determine the standard of bearing life, the bearing life is related to reliability.
Due to the difference of manufacturing accuracy and material uniformity, even the same material and the same size of the same batch of bearings are used under the same working conditions, their service life is not the same.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 the longest life to the shortest life is 20-40 times.90% of the bearings do not pitting, and the revolutions or hours experienced are called the rated life of the bearings .
Rated dynamic load
In order to compare the bearing capacity of bearing resistance to pitting corrosion, it is stipulated that when the rated life of the bearing is 1,000,000 revolutions (106), the maximum load that the bearing can bear is the basic rated dynamic load, represented by C.
That is to say, under the action of rated dynamic load C, the reliability of this kind of bearing to work one million rotations (106) without pitting failure is 90%, and the greater the bearing capacity of C, the higher the bearing capacity.
For basic dynamic load rating
1.Radial bearings are pure radial loads
2.Thrust ball bearings are pure axial loads
3.Radial thrust bearing refers to the radial component that produces pure radial displacement