Distinguishing Bearing Failure Modes Based on Mechanisms and Symptoms

When motor bearings malfunction, replacement is often the default solution. However, identifying the root cause requires professional inspection and analysis. By examining failure mechanisms and symptoms, we can categorize bearing issues as follows:  

--First, the bearing experiences wear failure--

Wear and tear is an inevitable problem for mechanical operating products. Under normal circumstances, bearings are safe throughout their service life. However, when hard particles, contaminants, oxides, etc. invade the bearings, it will accelerate the wear of the bearings. During the motor production process, metal shavings from the processing of components, extruded metal shavings during assembly, and any other form of foreign objects entering the bearings can all cause abnormalities in the bearing raceways or rolling elements. In this case, the motor bearings are more likely to exhibit noise and be accompanied by irregular vibration. When inspecting the bearings, it can be found that some of the rolling elements have been worn out.

--Second, plastic indentation failure--

When the actual load on the bearing is too large, especially under impact load conditions, the balls or raceways of the bearing will deform to varying degrees. This deformation occurs instantaneously when the load suddenly increases, and at the same time, the motor bearing and even the entire motor are accompanied by relatively severe and obvious vibrations. Therefore, for heavy-load and shock load conditions, bearings with greater load capacity should be selected, and at the same time, the strength of the shaft should be strengthened as necessary.

--Third, fatigue spalling failure--

It mainly refers to the damage or cracks on the surface or even deep layers of the bearing caused by external stress. The occurrence of this problem is closely related to the fit of associated components and the lubrication of bearings. For solutions with relatively reasonable and mature fit relationships, more attention should be paid to the lubrication status of the bearings. Better lubrication conditions can improve the operating life of the bearings and thereby ensure that the mechanical performance of the motor meets the requirements.