Roller bearings may be damaged due to various reasons during operation, such as improper assembly, poor lubrication, moisture and foreign body intrusion, corrosion and overloading, etc., which may lead to premature bearing damage. Even if the installation, lubrication and maintenance are normal, after a period of operation, the jnsn bearing will experience fatigue spalling and wear and cannot work properly. The main failure forms and causes of rolling bearings are as follows: