How to detect the condition of lathe spindle bearings ? What are the causes of damage ?

Spindle bearings are important components for the normal operation of various lathe equipment. During the operation of the equipment, the condition of the machine tool spindle bearings can be judged by listening to the sound, measuring the accuracy, observing the load, observing the appearance, etc. If problems are found, they can be replaced in time.
The general reasons for damage to machine tool spindle bearings are as follows (overload operation, long-term lack of maintenance, improper installation method, and harsh working environment).