The rolling track sound is a stable and continuous noise generated by the rolling elements rolling in the rolling track during the rotation of deep groove ball bearings. It only attracts people's attention when its sound pressure level or tone is extremely high. In fact, the sound energyl excited by the raceway sound is limited. Under normal circumstances, the high-quality bearing raceway sound is 25-27dB. This type of noise is typical of bearings that bear radial loads, and it has the following characteristics: a. Noise and vibration have randomness; b. Vibration frequency above 1kHz; c. No matter how the speed changes, the main frequency of noise remains almost unchanged, while the sound pressure level increases with the increase of speed; d. When the radial clearance increases, the sound pressure level increases sharply; e. As the rigidity of the bearing seat increases, the total sound pressure level decreases. Even if the speed increases, the total sound pressure level does not increase significantly; f. The higher the viscosity of the lubricant, the lower the sound pressure level, but for grease lubrication, its viscosity and the shape and size of soap fibers can both affect the noise level.
The generation of raceway noise is caused by the inherent vibration of the ring after being subjected to load. Due to the elastic contact between the collar and the rolling element, a nonlinear vibration system is formed. When the lubrication or machining accuracy is not high, it will excite inherent vibrations related to this elastic characteristic, which will become noise when transmitted to the air. As is well known, even if thel most advanced manufacturing technology is used to process deep groove ball bearing parts, there will always be slight geometric errors of varying degrees on the working surface, which will cause small fluctuations between the raceway and rolling elements to excite the inherent vibration of the vibration system.
Although the raceway noise of bearings is inevitable, high-precision machining of the working surface of parts, correct selection of bearings, and precise use of bearings can be adopted to reduce noise and vibration.