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Raceway noise is a kind of stable and continuous noise excited by the rolling body rolling in the Bearing Raceway raceway when the NTN bearing rotates. People pay attention to it only when its sound pressure level or tone is very large. In fact, the sound energy excited by the raceway sound is limited.
For example, under normal conditions, the high-quality Bearing Raceway 6203ntn bearing raceway sound is 25 ~ 27db. This kind of noise is typical of single row deep groove ball NTN bearing under radial load. It has the following characteristics: A. noise and vibration are random; b. The vibration frequency is above 1kHz;
c. No matter how the rotating speed changes, the main Bearing Raceway frequency of noise is almost unchanged, while the sound pressure level increases with the increase of rotating speed; d. When the radial clearance increases, the sound pressure level increases sharply; e. When the rigidity of NTN bearing pedestal increases,
the lower the total sound pressure level is, even if the speed Bearing Raceway increases, the total sound pressure level does not increase much; f. The higher the viscosity of lubricant, the lower the sound pressure level, but for grease lubrication, its viscosity and the shape and size of soap fiber can affect the noise value.
The elastic contact between the ferrule and the rolling body Bearing Raceway constitutes a nonlinear vibration system. When the lubrication or machining accuracy is not high, the natural vibration related to this elastic feature will be excited, and when it is transmitted to the air, it will become noise.
As we all know, even if the contemporary superb manufacturing technology is used to process NTN bearing parts, there will always be varying degrees of small geometric errors on the working surface, resulting in small fluctuations between the raceway and the rolling body and exciting the natural vibration of the vibration system.
Although the raceway noise of NTN bearing is inevitable, the Bearing Raceway correct selection of NTN bearing and accurate use of NTN bearing can reduce noise and vibration when adopting high-precision machining of parts’ working surface.
It is important to keep NSK Bearings and lubrication clean.
Clean the surface of the machine before inspection, and then Bearing Raceway remove the parts around the NSK bearing. The oil seal is a very fragile part, so it needs to be disassembled carefully.
Do not apply excessive force, and then carefully check the oil seal and its surrounding parts. If there are bad symptoms, be sure to replace it. The bad oil seal will cause damage to NSK bearing and severe equipment shutdown.
Cover exposed NSK Bearings:
When inspecting NSK Bearings, never expose NSK Bearings to pollutants or moisture. If the work is interrupted, the machine shall be covered with oil paper, plastic sheet or similar materials.
If it is possible to clean the NSK bearing without cover without disassembly, clean it with a brush coated with white spirit, and then wipe it dry with a piece of lint free cloth or blow it dry with compressed air (be careful not to start the rotation of NSK bearing assembly).
Check lubricant:
Rub a little lubricant between your fingers. If there are pollutants, you can feel it, or apply a thin layer of lubricant on the back of your hand, and then seal it for light inspection.
Change lubricant:
After draining the old engine oil, if possible, fill the NSK bearing with fresh engine oil and let the machine rotate at low speed for a few minutes. Make the engine oil collect residual pollutants as much as possible, and then drain the engine oil. The engine oil is filtered before use.
For grease lubricated NSK Bearings, the arbor used when replacing grease should avoid connecting the angle of cotton to any part of NSK Bearings, because these residual fibers may wedge between rolling parts and cause damage, especially for the application of small NSK Bearings.