1.Vibration of bearing rolling elements
In the ball bearings and roller bearings of large-scale vibrating screens, when the bearings mainly bear radial loads and rotate at low speeds, rolling body rolling vibration will occur. It was found in the test that when the imported bearing is under the radial load and the grease performance is poor, the vibration sound of "clicking \ clicking" will be heard at the beginning of operation, which is mainly due to the sudden acceleration and retention of the rolling elements after leaving the load zone The sound of vibration caused by the collision of the racks is inevitable but will disappear after a period of operation.
When the bearing is operated under the radial impact load of the vibrating screen, only a few rolling elements bear the load inside. Due to the "spring" support formed by the elastic contact with the ferrule, the rolling element generates periodicity through the radial load action line. Vibration (while the center of the shaft will therefore move vertically or horizontally). Especially when the vibration frequency of the shaker is low, this kind of vibration performance is more obvious.
2.Vibration of bearing rings
The imported rolling bearing vibration is basically caused by the vibration of the bearing ring, and it is related to the bearing structure, rigidity, manufacturing accuracy, installation conditions and use conditions. If there is a large radial ripple on the inner ring raceway of the bearing, the outer ring of the bearing will generate radial vibration when the inner ring rotates. The ripple of the inner ring of the bearing will not only cause the radial vibration of the outer ring, but also the axial vibration of the outer ring. When the bearing is subjected to axial load, the axial relative position of the inner and outer rings of the bearing will be changed. When the inner ring rotates, the outer ring of the bearing also generates an axial vibrating mouth. When the vibrating screen is working, for a high-speed rotating bearing, the vibration frequency caused by the ripple may be equal to the frequency of the shaker shaft, that is, Resonance.
3.Friction vibration of bearings
Friction vibration mainly refers to the abnormal vibration of imported rolling bearings. Generally speaking, friction vibration easily occurs on large ball bearings. It is more likely to occur when grease lubrication is used, especially when the lubrication performance is not good. According to tests and observations, the generation of frictional vibration of rolling bearings is often directly related to the properties of lubricants. When the lubricating oil has poor performance or is not clean, frictional vibration is easy to occur, and it is also related to the processing quality of the rolling bearing outer raceway. If a special and precise processing method is used for this, the frictional vibration can be better controlled.
4.Vibration of bearing cage
The vibration of the cage is mainly caused by the collision between the cage and the rolling body when the bearing rotates. When the vibrating screen works, accompanied by various alternating loads such as impact loads, it will cause severe vibration of the cage. This vibration is generally considered to be the natural vibration of the cage due to sliding friction between the rolling elements and the cage. .
Cage vibration is mainly generated in ball bearings and tapered roller bearings. It is easy to occur in situations such as excessive radial clearance, poor lubrication performance, and torque fluctuations on the shaker shaker shaft.
5.Local damage
Due to operation or installation errors, a small number of bearing raceways and rolling elements may be damaged. During operation, rolling through damaged bearing components will produce a specific vibration frequency. Damaged bearing components can be identified by vibration frequency analysis.
4.Vibration behavior in applications
In many applications, the stiffness of an bearing is the same as that of the surrounding structure. Because of this feature, as long as the imported bearings (including preload and clearance) are properly selected and their configuration in the application, it is possible to reduce the vibration in the application.
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