NSK bearing noise - bearing the nature of knowledge

For use of bearing, the noise is very common. Even low noise bearings of NSK bearings have the same situation. Why, then, will produce noise? Today I give everybody to introduce its essence. ( 1) Bearing raceway groove sound sound and its control method is when bearing is running, rolling on the surface of the raceway of the rolling element and a line of continuous sound, is unique to occur in all rolling bearings of the basic sound. General sound of NSK bearing raceway is combined with other sounds. Ball bearing raceway is irregular, frequency above 1000 hz, its main frequency does not change with speed, but its total sound pressure level increases with speed to speed up. Raceway large bearings, the rolling sound of sound pressure level decrease with the increase of the viscosity; The raceway small bearings, the sound pressure level in the viscosity increases to about 20 was/s above, from decreased to increase somewhat. And the rigidity of the bearing, the greater the raceway of the lower the total sound pressure level. Such as radial clearance is too small, the total sound pressure level and race master frequency will increase sharply with the decrease of radial clearance. Control of raceway acoustic methods are: using low noise bearing is bearing waviness is very small, that is, carefully select and use conditions. Race often affect the mechanical noise, reduce the raceway can reduce the mechanical noise. ( 2) Impact of the rolling element and its control method for larger models of ball bearings or cylindrical roller bearings under pure radial load speed, due to centrifugal force is lesser, roller in the rolling body will impact the load area or race and making noises. But with the increase of rotational speed, the noise will disappear. Control method of rolling body impact sound: decrease the radial clearance, materials for use with reasonable structure and flexibility of the bearing cage. ( 3) NSK import bearing of rolling mill rolling mill and its control method is cylindrical roller bearing in the harsh metal can occur in all occasions, mostly happens in large type bearing grease lubrication, and in the base oil performance degradation occurred more often in grease, almost does not occur when oil lubrication. In addition, more easily occur during the winter, when under pure radial load, the radial clearance prone to big occasions, and with different size, easy to happen in a certain speed range, both continuous and intermittent. External ring raceway take special processing method can prevent the occurrence of roll ring, can choose this kind of bearing, if necessary or appropriate to reduce bearing radial clearance, the use of high performance grease and improve to suit the bearing parts of rigidity.