Cause and analysis of anti-friction bearing failures in AC induction motors

Bearing failures have accounted for an increased percentage of motor failures. This is due in part to improved stator and rotor construction, which may result in the bearings being the weak link. Also many bearings are being operated at increased loads, temperatures, and speeds. The environment is another major factor affecting bearing life. All too often the failed bearing is replaced without proper identification of the root cause of the failure. Hence, proper corrective actions may not be taken to minimize or avoid future failures, and extend bearing life. A methodology for identifying the cause of failure for antifriction bearings used in electric motors using antifriction bearings is presented.<>