Bearings have a fundamental and extensive application in various machinery. They are a very important mechanical component, and in academic terms, their main function is to support the rotating body of the machinery, reduce the friction coefficient during its motion, and ensure rotational accuracy.

In general, a complete bearing not only includes the shaft and bearing seat, but also lubricants and seals, which are also very important components. To maintain the effective operation of bearings, it is necessary to use appropriate lubricants and effective seals to prevent contaminants from entering the bearing system. Based on past experience with bearing use, cleanliness has a significant impact on the efficiency and lifespan of bearings. So we can also understand why many bearing manufacturers' business scope covers sealing and lubrication services.

The size and load of bearings directly affect their service life. Generally, the selection process of bearings is to preliminarily determine the required bearings based on the load, and then according to the products listed in the product table and the possible large loads that may occur. Static load not only refers to the load acting on bearings at rest or very low speeds (n<10r/min), but also the static load safety factor under heavy impact loads (loads acting for a short period of time) should be checked.

In the formula for the rated life of bearings, other external forces such as lubrication and surface smoothness need to be taken into account to consider their actual service life. For rolling contact surfaces, metal fatigue is the main cause of damage.

As a microscopic working system, the actual service life of bearings depends on the components that are initially damaged, so the ideal state is for all components to reach the end of their service life at the same time. Based on previous bearing damage data, metal fatigue is the main factor causing damage.