The fault symptoms of rolling bearings are generally manifested in two ways: one is that the temperature at the installation site of the bearing is too high, and the other is that there is noise during the operation of the bearing.

1. The bearing temperature is too high

During the operation of the mechanism, a certain temperature is allowed at the location where the bearings are installed. When touching the mechanism housing with hands, it should be considered normal not to feel hot, otherwise it indicates that the bearing temperature is too high.

The reasons for high bearing temperature include: the quality of lubricating oil does not meet the requirements or has deteriorated, and the viscosity of lubricating oil is too high; The assembly of the mechanism is too tight (insufficient clearance); The bearing assembly is too tight; The bearing race rotates on the shaft or inside the housing; Excessive load; Bearing cage or rolling element breakage, etc.

2. Bearing noise

Rolling bearings are allowed to have slight operating noise during operation. If the noise is too loud or there is abnormal noise or impact sound, it indicates that the bearing is faulty.

The reasons for the noise generated by rolling bearings are quite complex, one of which is the wear of the mating surfaces of the inner and outer rings of the bearing. Due to this wear, the mating relationship between the bearing and the housing, as well as between the bearing and the shaft, is disrupted, resulting in the axis deviating from its correct position and producing abnormal noise when the shaft is moving at high speeds. When the bearing is fatigued, the surface metal peels off, which can also increase the radial clearance of the bearing and produce abnormal noise. In addition, insufficient lubrication of bearings, dry friction, and bearing breakage can all produce abnormal sounds. After bearing wear and looseness, the cage may become loose and damaged, which can also produce abnormal noise.