It is not uncommon for the
bearing to malfunction during operation, so there is no need to make a fuss. A failure has occurred and it is critical to judge and deal with it. Today we will explain the common faults of FAG bearings and how to eliminate them.
1. Bearing temperature is too high
When the mechanism is running, the part where the bearing is installed is allowed to have a certain temperature. When the body of the mechanism is touched by hand, it should be normal to not feel hot, otherwise the bearing temperature is too high.
The reasons for the bearing temperature being too high are: the quality of the lubricating oil does not meet the requirements or deteriorates, the viscosity of the lubricating oil is too high; the assembly of the mechanism is too tight (the gap is insufficient); the bearing assembly is too tight; the bearing race rotates on the shaft or inside the casing; Large; bearing cage or rolling body fragmentation.
2. Bearing noise
Rolling bearings allow a slight running noise during operation. If the sound is too loud or there is abnormal noise or impact, the bearing is faulty.
The causes of noise generated by rolling bearings are more complicated. One is the wear of the inner and outer rings of the bearing. As a result of this wear, the bearing and the housing, the bearing and the shaft are broken, causing the axis to deviate from the correct position and produce an abnormal sound when the shaft is moving at a high speed. When the bearing is fatigued, the surface metal peeling off will also increase the radial clearance of the bearing to produce abnormal noise. In addition, insufficient bearing lubrication, dry friction, and bearing crushing can produce abnormal sounds. After the bearing wears loose, the cage is loose and damaged, and the abnormal bearing damage will also occur.
When the rolling bearing is disassembled and inspected, the bearing failure and the cause of damage can be judged according to the damage of the
bearing.
Rolling surface metal peeling
The bearing rolling elements and the inner and outer ring raceways are subjected to periodic pulsating loads, resulting in periodic changes.
Contact stress. When the number of stress cycles reaches a certain value, fatigue peeling occurs on the rolling element or the inner and outer ring raceways. If the bearing load is too large, this fatigue will be exacerbated. In addition, the bearing is not installed correctly, the shaft is bent, and the raceway is peeled off. Fatigue spalling of the bearing races reduces the accuracy of the shaft and causes vibration and noise in the mechanism.
2. Bearing burns
Burned bearings have a tempering color on the raceways and rolling elements. The causes of burns are generally insufficient lubrication, the quality of the lubricant does not meet the requirements or deterioration, and the bearing assembly is too tight.
3. Plastic deformation
Uneven pits appear on the contact surface between the raceway and the roller of the bearing, indicating that the bearing is plastically deformed. The reason is that under the action of large static load or impact load, the local stress of the working surface exceeds the yield limit of the material.
This type of situation generally occurs on bearings that rotate at low speeds.
