Analysis of Main Causes of Vibration of Rolling Bearings

The main reason for the vibration of the rolling bearing is that due to the load, the rolling bearing is deformed and vibration is caused when the rolling bearing rotates.

1 Vibration of bearing rings The vibration of rolling bearings is basically caused by the vibration of the bearing rings, which is related to the bearing's structure, stiffness, manufacturing accuracy, installation conditions, and usage conditions. If there is a large radial ripple on the raceway of the inner ring of the bearing, the outer ring of the bearing will generate radial vibration when the inner ring rotates. The undulation of the inner ring of the bearing not only causes radial vibration of the outer ring, but also causes axial vibration of the outer ring. When the bearing is subjected to axial load, the axial relative position of the inner ring and the outer ring of the bearing changes. When the inner ring rotates, the outer ring of the bearing also generates an axial vibration port. When the vibrating screen is in operation, the vibration frequency caused by the corrugation may be equal to the rotating frequency of the exciter shaft for the bearing that rotates at a high speed. Resonance.

2 Vibration of the cage's vibration holder is mainly due to the vibration of the cage and the vibrating rolling element when the bearing rotates. When vibrating screen is working, along with various alternating loads such as impact load, it will cause severe vibration of the cage. This kind of vibration is generally considered to be "caused by the friction of the cage caused by the sliding friction between the rolling element and the cage. Excited vibration.

The cage vibration is mainly generated in ball bearings and tapered roller bearings, and occurs easily when the radial clearance is too large, the lubrication performance is not good, and the torque fluctuation of the vibration shaker shaft is transmitted.

3 Rolling body vibration In ball bearings and roller bearings of large vibrating screens, when the bearings are mainly subjected to radial load and rotate at a low speed, the falling vibration of the rolling bodies will occur. The test found that when the bearing under the action of radial load and poor grease performance, early in the operation will hear "咔嚓 \ 咔嚓" vibration, this is mainly due to the sudden acceleration of the rolling body and cage after leaving the load zone The vibrating sound that comes out of colliding, this kind of percussion sound is inevitable but will disappear after running for a while.

When the bearing is operated under the radial impact load of the vibrating screen, only a few rolling elements bear the load. Because of the “spring” support formed by the elastic contact with the ferrule, the rolling element generates periodic vibrations through the radial load acting wire. (And the shaft center will therefore move vertically or horizontally.) Especially when the vibration frequency of the vibrating screen is low, such vibration performance is more obvious.

4 Frictional vibration Frictional vibration mainly refers to the abnormal vibration of the rolling bearing. In general, the frictional vibration is easy to occur on large ball bearings. It is easier to use grease lubrication, especially if the grease has poor lubricating performance. According to tests and observations, the generation of frictional vibration of rolling bearings is often directly related to the properties of lubricating oils. When the performance of lubricating oil is not good or not clean, frictional vibration is easy to occur, and it is also related to the processing quality of the outer race of the rolling bearing. If a special and precise processing method is adopted for this, the frictional vibration can be better controlled.

The vibration of rolling bearings is often the result of a combination of the above types of vibration. Tests have shown that in the normal operation of the bearing, the waviness of the bearing part surface is the main factor causing the vibration of the bearing.