Bearing consists of inner and outer ring, rolling body (ball, roller, or needle roller and retainer of four parts, except the retainer, the rest are composed of bearing steel. When bearing, bearing inner and outer ring, rolling element bearings under high frequency, the effect of varying stress. Bearing working condition is very complex. Load concentrated on a small area of the roller. In theory for the ball, in point; For roller is in a line, and the contact area between the roller and ring is small (a point/line contact), so the bearing parts at work, the per unit area on the surface of the roller and the ring to bear a lot of pressure, general n/was as high as 1500-1500; When bearing rotation, bear the function of centrifugal force, force increases with the increase of rotational speed; Exists not only between roller and ring rolling, sliding, and so there is friction between roller and ring. A combination of the above several force,FAG 6321 bearings company http://www.fagbearings-hk.com/product/FAG-6321-bearings-1757.html in the ring or on the surface of roller low fatigue strength of parts in the first place to produce fatigue crack, finally form the fatigue spalling, disable bearing damage. Bearing the breakage of the normal form is contact fatigue damage, common, indentation, wear and plastic deformation, crack, etc.
The life and reliability of the bearing with bearing design, processing and manufacturing, installation, maintenance, lubrication condition factors, but the high quality and reliability of the bearing material is the key. To rolling bearing part on the tensile, compression, bending, shear, alternating under complex stress state and high stress value, such as high speed and work over a long period of time. Therefore, the rolling bearing with:
1) high plastic deformation resistance,
2) high resistance to friction and wear performance,
3) the rotation of the high precision and the dimensional accuracy,
4) good dimensional stability,
5) long service life and high reliability.
For bearing work under special conditions, there are special requirements, such as high temperature resistance, low temperature resistance, corrosion resistant performance and resistance to magnetic and so on.