Analyze the method of controlling the noise of the bearing
We know that ntn bearings generate various noises due to friction during operation, and some bearing noises will be larger. In fact, if we can handle the bearing process well, the noise can be controlled. The essential noise of the bearing is that the bearing that is manufactured using modern machining technology still occurs, and the structure of the bearing itself determines the noise. The essential noise can be divided into three types: raceway sound, rolling body impact sound and rolling sound, which are described as follows:
(1) Rolling sound of ntn bearing and its control method
The rolling sound is a slippery continuous sound that the rolling elements roll on the raceway surface when the bearing is running, which is the unique basic sound that all rolling bearings will produce. The general bearing sound is the rolling sound plus other sounds.
The ball bearing's raceway sound is irregular, the frequency is above 1000Hz, its main frequency does not change with the speed, but its total sound pressure level increases with the increase of the speed.
The ntn bearing with large rolling track has the sound pressure level of the rolling track sound decreasing with the increase of the viscosity; while the bearing with small rolling sound, the sound pressure level is reduced when the viscosity is increased to above 20mm2/s. Turned to increase. The greater the rigidity of the bearing housing, the lower the total sound pressure level of the raceway sound. If the radial clearance is too small, the total sound pressure level and main frequency of the raceway sound will increase sharply as the radial clearance decreases. The method of controlling the rolling sound is to select a low-noise bearing, that is, a bearing with a small waviness, and carefully select the conditions of use. The raceway sound often affects the noise of the entire machine, and reducing the raceway sound can reduce the noise of the entire machine.
(2) Impact sound of rolling element and its control method
When a larger type of ball bearing or cylindrical roller bearing is operated at a low speed under pure radial load, the rolling element in the non-loading area will hit the cage or the raceway to generate noise due to the small centrifugal force of the rolling element. But as the speed increases, the sound will disappear. The control methods for the impact sound of the rolling element are: appropriately reducing the radial clearance, and using a bearing having a reasonable structure and a flexible material.
