Shaft parts of CNC lathe, especially angular contact spindle bearings, generally rotate at a very high speed ratio, sometimes resulting in a very high heat output. If this situation is not interfered for a long time, it will cause the angular contact ball bearing to overheat, and cause the temperature of the corresponding position of the CNC lathe to rise, resulting in thermal expansion, and may even make the machine tool spindle and tailstock not level, which not only affects the precision and dimensional accuracy of the CNC lathe itself, but also burns the bearing.
Rated fatigue life refers to the total speed at which 90% of angular contact ball bearings do not fall off due to overturning fatigue when a group of bearings of the same model are operated in the same environment. When the speed ratio is stable, the rated fatigue life is usually expressed by the total running time.
When studying the life of angular contact spindle bearing, fatigue life should not be considered only, but also be considered comprehensively according to the performance of the bearing. For example, the grease life of grease-lubricated bearings. Noise life, damage life, etc., are different according to their use and application limit standards. Therefore, most of them choose the work experience limit in advance.
The judgment of the availability of angular contact bearings is usually determined by considering the bearing damage level, physical performance, necessity, operation standard and the period to the next maintenance. If there are any of the following defects, they cannot be reused. Be sure to replace the thrust ball bearing with a new one. There are cracks or gaps on any of the inner hole, outer side, rolling element and ball bearing. Wear failure is one of the most common failure modes of various bearings. According to the damage mode, it can be divided into more common abrasive wear and adhesive wear.