Ultra-precision angular contact ball bearings must guide the high-precision operation of mechanical parts and ensure sufficient support during high-speed operation. Therefore, the selection of the bearing mainly considers the main factors of accuracy, rigidity and running performance. When loading, it must be ensured that there is a lubricating oil film in the contact area between the rolling element and the raceway. Under the condition of oil film, the actual fatigue life of the bearing will be longer. If the bearing is to reach the fatigue life, the life of the bearing is deeply affected by the life of the lubricant. The factors that determine the working life of the bearing under relevant load conditions are the size of the contact stress in the contact area between the rolling elements and the raceway and the dynamic performance of the bearing. In the actual working process, super-precision bearings will not fail due to fatigue, but failure caused by the loss of grease life.

The fatigue life of ultra-precision angular contact ball bearings generally depends on the working life of the lubricant. In many cases, the life of the lubricant determines the life of the bearing. The relative influence on the fatigue life of the bearing is relatively small.