It is very common for bearings to produce noise.The same is true even for low-noise bearings imported from KOYO, Japan.So why the noise?Today I will introduce its essence to you.(1) The raceway sound of KOYO inlet bearing and its Control Method Raceway sound is a kind of slippery continuous sound produced by the rolling body rolling on the raceway surface when the bearing is running. It is a unique basic sound that all rolling bearings can produce.The general bearing sound is the raceway sound plus other sounds.The raceway sound of ball bearing is irregular, with the frequency above 1000Hz. Its main frequency does not change with the speed of rotation, but its total sound pressure level increases with the speed of rotation.For bearings with large raceway sound, the sound pressure level of raceway sound decreases with the increase of viscosity.For KOYO inlet bearing with low raceway sound, its sound pressure level increases from decreasing to increasing when the viscosity increases to about 20mm2/s or above.The greater the rigidity of bearing housing, the lower the total sound pressure level of raceway sound.If the radial clearance is too small, the total sound pressure level and main frequency of raceway sound will increase sharply with the reduction of radial clearance.The methods of controlling raceway sound include: selecting low noise bearing, that is, imported bearing with small ripple degree, carefully selecting the conditions of use.Raceway sound often affects the noise of the whole machine. Reducing raceway sound can reduce the noise of the whole machine.
(2) Impact sound of rolling Body and Its Control Method When larger ball bearings or cylindrical roller KOYO bearings operate at low speed under pure radial load, the rolling body in the non-load zone will impact the cage or raceway and give out noise due to the small centrifugal force of the rolling body.But as the speed increases, the sound disappears.The control methods for the impact sound of the rolling body include: reducing the radial clearance appropriately and using bearings with a reasonable structure and a flexible material cage.
(3) The rolling sound of KOYO bearings imported from Japan and its Control Method The rolling sound is the grating metal friction sound that can occur in all occasions of cylindrical roller bearings. It mostly occurs in the larger type bearings with grease lubrication, but it is more likely to occur in the lubricating grease with deteriorating base oil performance, and almost does not occur during oil lubrication.In addition, it is relatively easy to occur in winter. When the inlet bearing bears pure radial load, it is easy to occur in occasions with large radial clearance, and with different models and sizes, it is easy to occur within a specific speed range, which can occur continuously or intermittently.Special machining methods for outer ring raceway can prevent the rolling sound, such bearings can be used if necessary, or the radial clearance of bearings can be reduced appropriately, excellent lubricating grease can be used and the rigidity of matching KOYO imported bearing bearings can be improved.