Distinguish the failure states of bearings based on their failure mechanisms and manifestations.

When motor bearings encounter problems, it is common practice to directly replace the bearings; however, to determine the cause of the bearing issues, professional testing and evaluation are necessary for analysis. From the mechanism of bearing failure and its specific manifestations, the following aspects can be analyzed: 
First, the bearing experiences wear-induced failure. Wear is an inevitable issue for mechanical operating products. Under normal circumstances, the bearing is safe throughout its service life. However, when hard particles, contaminants, oxides, etc., intrude into the bearing, it will accelerate the wear of the bearing. Metal shavings from the processing of components during motor production, metal shavings from the assembly process, or any other form of foreign matter entering the bearing can cause abnormalities in the bearing raceway or rolling elements. In such cases, the motor bearing is more likely to produce abnormal noises accompanied by irregular vibrations. When inspecting the bearing, it can be found that some rolling elements have been worn. 
Second, plastic indentation failure. When the actual load on the bearing is too large, especially in the case of impact loads, the balls or raceways of the bearing will undergo varying degrees of deformation. This deformation occurs instantaneously when the load suddenly increases, and the motor bearing and even the entire motor will experience relatively intense and obvious vibrations. Therefore, for heavy loads and impact load conditions, bearings with greater load capacity should be selected, and the strength of the shaft should be appropriately enhanced. 
Third, fatigue spalling failure. This mainly refers to damage or cracks on the surface or even deep within the bearing caused by external stress. The occurrence of this problem is closely related to the fit of associated components and the lubrication of the bearing. For schemes with relatively reasonable and mature fit relationships, more attention should be paid to the lubrication state of the bearing. Good lubrication conditions can improve the operational life of the bearing and thereby ensure that the mechanical performance of the motor meets the requirements.