Falling body rolling sound, the noise is generally found in large bearings that are under low speed and bear radial load. When the bearing is running under radial load, the load area and non-load area in the bearing. If the bearing has a certain radial clearance, the rolling elements in the non-load area do not contact the inner raceway, but may contact the outer ring due to centrifugal force. At low speed, when the centrifugal force is less than the dead weight of the rolling elements, the rolling elements will fall and collide with the inner raceway or cage to stimulate the inherent vibration and noise of the bearing.

And has the following characteristics: for only the role of radial load and radial clearance is also easy to produce. It is also produced in a certain range and the speed range of bearings of different sizes is also different. Grease lubrication is easy to produce, oil lubrication is not easy to produce. It is more likely to occur when using inferior grease. It may be a continuous sound or a discontinuous sound. Winter often happens.

The forced vibration often excites the second-order and third-order bending natural vibration of the outer ring, thereby emitting the noise. By using the preload method can effectively reduce the noise, reduce the radial clearance of the bearing after installation, the selection of good lubricants can also be improved, some foreign enterprises use light rolling bodies, such as ceramic rollers or hollow rollers and other technical measures to prevent the generation of this noise. The rolling element vibrates. When the bearing operates under the action of radial load, only if the rolling element bears the load inside, the spring support formed by the elastic contact with the ferrule causes the rolling element to generate periodic vibration through the action line of radial load, and the center of the rotating shaft will therefore move up and down vertically or horizontally, causing noise at the same time. This type of vibration is called rolling body through vibration, especially at low speed operation is more obvious. The amplitude is related to the bearing type, radial load, radial clearance and the number of rolling elements. Usually the amplitude is small, if the amplitude is large to form a hazard, it is often used to reduce the radial clearance or apply appropriate preload to reduce. The screech is a very violent scream produced by sliding friction between metals. Although the bearing temperature rise is not high at this time, it has little effect on the bearing life and grease life, and does not affect the rotation, but the unpleasant sound is disturbing, especially It is often the noise of large short cylindrical roller bearings that bear radial load.

Cage noise, which is emitted by the free vibration of the cage during the rotation of the bearing and its impact with the rolling elements or rings. It may occur in all types of bearings, but its sound pressure level is not too high and is low frequency. Its characteristics are: whether it is thin oil or grease lubrication will appear. Both stamped cages and plastic cages can be produced. It is easy to appear when the radial clearance is large. It is easy to occur when the outer ring is subjected to a bending moment.

Since the cage pocket clearance and the cage and ring clearance inevitably exist in the finished bearing, it is very difficult to eliminate the cage sound, but it can be improved by reducing the assembly error and optimizing the reasonable clearance and cage movement. Another cage special sound is the noise that occurs due to the self-excited vibration of the cage caused by the friction between the cage and the guide surface of other bearing parts. The stamping cage of deep groove ball bearings is thin, the bending stiffness in the radial and axial planes is low, and the overall stability is poor. When the bearing rotates at high speed, it will produce self-excited vibration due to bending deformation, causing buzzing.

When the bearing is under the action of radial load and the grease performance is poor, the noise of clicking and clicking will be heard at the beginning of operation. This is mainly due to the sudden acceleration of the rolling body and the collision with the cage after the rolling body leaves the load area. The noise emitted by the collision, this impact sound is inevitable but will disappear after a period of operation. The measures to prevent cage noise are as follows: when the bearing rotates at high speed, the vibration amplitude of the cage with large pocket gap is much larger than that of the cage with small pocket gap, so the value of pocket gap is particularly important. In order to stabilize the revolving movement of the cage, the ferrule guide method should be adopted as much as possible and attention should be paid to the sufficient lubrication of the guide surface. The structure of the tapered roller bearing under high-speed working conditions should be improved, and the L-shaped cage guided by the roller should be changed to the Z-shaped cage guided by the ferrule rib.

Care should be taken to minimize the radial clearance. Improve the manufacturing accuracy of the holding price as much as possible, improve the surface quality of the cage, and help reduce the noise generated by the collision or friction between the rolling element and the cage. Actively adopt advanced cleaning technology to effectively clean the spare parts and the products after the set, and improve the cleanliness of the bearing.