Track sound
Raceway sound is a kind of smooth and continuous noise that is caused by the rolling elements rolling in the raceway when the bearing rotates. It only attracts people's attention when its sound pressure level or tone is extremely large. In fact, the sound energy excited by the raceway sound is limited. For example, under normal circumstances, the high-quality 6203 bearing raceway sound is 25-27dB. This kind of noise is the most typical single-row deep groove ball bearing that bears radial load. It has the following characteristics: a. Noise and vibration are random; b. The vibration frequency is above 1kHz; c. Noise main frequency regardless of the speed change Almost unchanged and the sound pressure level increases with increasing speed; d. When the radial clearance increases, the sound pressure level increases sharply; e. The rigidity of the bearing housing increases, and the lower the total sound pressure level, even if the speed increases , Its total sound pressure level does not increase much; f. The higher the viscosity of the lubricant, the lower the sound pressure level, but for grease lubrication, its viscosity and the size of the soap fiber can affect the noise value.
The origin of the raceway sound is caused by the natural vibration of the ferrule after receiving the load. The elastic contact between the ferrule and the rolling body constitutes a non-linear vibration system. When the lubrication or machining accuracy is not high, the natural vibration related to this elastic characteristic is excited, and when it is transmitted to the air, it becomes noise. As we all know, even if the bearing parts are processed using the most advanced manufacturing technology, there will always be slight geometric errors of varying degrees on the working surface, so that small fluctuations between the raceway and rolling elements will excite the inherent vibration of the vibration system. Although it is unavoidable, it is possible to adopt high-precision machining of the work surface of the part, the correct selection of bearings and the accurate use of bearings to reduce noise and vibration.