The fracture phenomenon of rolling bearing ring is caused by the fatigue of the raceway: usually a large area of u200bu200bthe raceway fatigue failure; often in the fracture area is stepped (sometimes linear), see Figure 63 Reason: further development of fatigue Damage remedial measures: see section 3.3.2.1 Fracture. 3.3.3.2 Axial original cracks of the inner ring and through cracks of the inner ring: Part or all of the ferrule is broken in the axial direction. Slightly round fracture: It indicates that a fracture occurred during operation and continues to operate. The sharp fracture indicates that it was produced during the disassembly process. After a long-term operation of a cracked bearing, the sharp fracture edge will partially peel off, as shown in Figure 64. Reasons: bearing slippage, raceway fracture, inner ring rotating on the shaft, improper lubrication, too tight fit with the shaft, groove on the shaft surface, insufficient roundness, scratching with surrounding parts. Remedial measures: Improve lubrication (additives, increase the amount of lubricating oil). Remedial measures for raceway damage. Choose a suitable fit. Avoid scratches on surrounding parts. Provide a better mating surface. Special heat treatment of the ring. 40 Evaluate the running characteristics of the removed bearing. And damage rolling contact mode 63: failure caused by axial fracture of the outer ring of deep groove ball bearing 64: axial crack of the inner ring of spherical roller bearing outer ring circumferential fracture phenomenon: usually cracks develop in the circumferential direction. Often broken into several pieces. Under axial load, these fractures often occur in areas deviating from the middle of the raceway. Fatigue is usually the cause of damage. The outer surface of the outer ring generally shows an abnormal load-bearing form, see Figure 65. Reason: Insufficient support of the ring matched with the bearing seat. Remedy: Improve the support.