The service condition of plane thrust bearing of worm shaft in an oil screw press was analyzed. The fracture failure of the bearing rings was systematically investigated through physical-chemical test, trace inspection, fractographic appearance, and metallographic structure analysis. The results showed that a great amount of network surface cracks near bearing ring edge, some dot shaped internal oxidations and secondary crack initiation, higher hardness, as well as the network carbides and coarse quenching martensites led to the early brittle fracture of the bearing rings. The further improvem...
