KOYO bearing surface fatigue failure reason analysis - bearing knowledge

Bearing failure analysis, in order to improve the working reliability of system engineering is an important part of the bearing surface, Bearing job functions in the loss of its rules, lead to failure or does not work as failure phenomenon called ( Bearing fault can be divided according to their normal life, failure and premature failure of the two, it mainly for pitting corrosion and fatigue cause of bearing early failure analysis and put forward Suggestions for improvement, in order to improve the KOYO import bearing life and reliability. KOYO bearing fatigue failure is a failure surface form, main performance for fatigue crack initiation, expansion and fracture process, under the alternating load generated by the fault of the long-term effects of the metal. Cracks in two aspects: first, on the surface, this is, KOYO import bearing in the process of rolling contact, because of the work in the plastic deformation and strain hardening on the surface of the contact stress on the surface of the cyclical changes caused by the effect of external load, and finally on the inner surface of the small crack from the development, the formation of surface crack between the two, because Xie into the lubricant on the surface of the work, the power of the open, crack down on the wall, crack force to move forward; Under the pressure of two: from the surface, again and again, the surface contact, the first where exposed on the surface of the crack depth of a crack, and along the surface direction Angle, to a certain depth, since on the surface of contact area, and beyond the surface, and finally form the corrosion, leaving a horse pit. On the surface, or from the surface of the crack, the two objectives ( Part carburizing, quenching and other surface heat treatment, if after have uneven hardness, organization, and the internal stress of non-uniform and other adverse, the contact stress is generally have the opposite under the influence of ground fissure, if parts surface quality is poor, there is a defect ( Oxidation and decarburization) Poor lubrication, friction or from the surface crack.