Damage status: the so-called crack refers to the raceway wheel or roll body crack damage. If it is used continuously, it will also include cracks in the crack.
Reason: too much excess. Overload and impact load. The divestiture has been carried out. Heat and micro vibration wear because of the touch of the raceway wheel and the device component. Heat caused by creep. The cone angle of the cone shaft is bad. The cylindricity of the shaft is bad. The corner radius of the shaft step is larger than the bearing for idler chamfering angle, forming the interference with the bearing for idler chamfering.
Method: the amount of interference is appropriate. Check the load condition. Improved device method. The shape of the shaft should be properly shaped.