Reasons for outer ring fracture of rolling mill stand roll bearing

A fracture accident occurred on the outer ring of the roller bearing in the wide and thick plate workshop of a certain steel plant. The causes of bearing outer ring fracture were analyzed using methods such as macroscopic observation, chemical composition analysis, mechanical performance testing, metallographic examination and scanning electron microscopy analysis. The results show that the bearing seat was deformed, led to partial loading of the bearing. The bearing rollers were subjected to abnormal axial forces, and the edge of the outer ring raceway of the bearing was subjected to heavy loads from the rollers, resulting in stress concentration. The material of the outer ring of the bearing was brittle, causing microcracks to form in the material. The cracks extended towards the inside of the raceway, ultimately led to the fracture of the outer ring of the bearing.