There are many reasons for the failure of cylindrical roller bearings. In addition to the normal bearing fatigue and fall off, many factors such as invalid sealing, too small bearing gap or poor smoothness caused by too tight fit can leave special invalid impressions and invalid ways. Therefore, invalid bearing inspection is not difficult to find bearing failure causes in most of the time, and then take relative countermeasures to avoid.

Generally speaking, 1/3 of the ineffectiveness of bearings is due to the fact that bearings are tired and fall off during the normal and invalid period; 1/3 early invalid due to poor bearing wetting. 1/3 early invalid due to contaminated substances entering outer spherical bearings or incorrect assembly. Generally speaking, the following seven symptoms are shown when the bearing is abnormal: bearing overtemperature, bearing noise is too big, bearing service life is too low, vibration is large, the technical performance of the equipment cannot be reached, the bearing is loose on the shaft, and the shaft rotation is difficult.

Bearing raceway sound and control measures raceway sound is a smooth and continuous sound emitted by the rolling body turning over on the raceway surface when the second class bearing is running, which is the unique basic sound that all overturned bearings will occur. The general sound of the outer spherical bearing is the raceway sound plus other sounds. The raceway sound of the bearing is irregular and its working frequency is about 1000Hz. Its main working frequency does not change with the speed ratio, but its total sound pressure level changes with the speed ratio. For bearings with loud raceway sound, the sound pressure level of raceway sound decreases with the increase of viscosity. While the raceway sound is a little smaller, the sound pressure level of the second class bearing is expanded from a decrease to a certain extent when the viscosity expands to more than 20mm2/s. The more stiffness of bearing seat, the smaller the total sound pressure level of raceway sound. If the radial clearance is too small, the total sound pressure level and the main operating frequency of raceway sound will increase sharply with the decrease of radial clearance. The way to manipulate raceway sound is to use low noise bearings, namely bearings with minimal ripple degree, and carefully use the applicable range. Raceway sound often affects the whole mechanical noise, reducing the raceway sound can reduce all mechanical noise.

Impact sound of rolling body and control measures. When large size bearings or outer spherical bearings run at low speed under pure radial load, because the centripetal force of rolling body is relatively small, the rolling body will impact ball bearings or raceways in the non-load area and make noise. But as the RPMS rise, the sounds disappear. The control measures for the impact sound of the rolling body include: appropriate reduction of radial clearance, the application of effective structure and material is compliant ball bearings of the second class.

Rolling sound of bearings and control measures Rolling sound is the squeaking sound of bearings in most places. The metal squeaking sound mostly occurs in relatively large size bearings with grease lubrication, but it is more likely to occur in lubricating oil with inferior base oil characteristics, and basically does not occur when the oil is moistened. In addition, it is easy to happen in winter, when bearing pure radial load, it is very easy to happen in the place where the radial clearance is larger, and it is not the same with the small size of the model specification, it is very easy to happen within a specific speed ratio range, which will continue to happen and intermittently. The use of special processing technology for the open ring raceway can prevent the occurrence of rolling sound. If necessary, this kind of outer spherical bearing is adopted, or the radial clearance of the bearing is appropriately reduced, and the application of excellent lubrication grease and improve the stiffness of the parts matching with the bearing is applied.