There are two kinds of noise caused by problems in bearing application: scar sound and dust sound, which are described as follows:
(1) Scar sound and its control method
If there is crack, indentation or corrosion on the rolling surface of rolling bearing, periodic vibration and noise like riveting rivets will occur. Its cycle may be fixed, but most of it has a certain corresponding relationship with the rotating speed. The scars will occur continuously on the channel, and the scars will appear on the steel ball from time to time, and this noise will change with the installation and lubrication conditions.
The control methods of this kind of noise include: do not knock the bearing during installation, and prevent the bearing from being installed obliquely when the bearing is assembled with the shaft and then installed into the bearing seat; Prevent bearing corrosion during storage and impact vibration during transportation; Use grease with high viscosity.
(2) Dust sound and its control method
If there are dust and other foreign matters in the rolling bearing, aperiodic vibration and so-called dust sound will occur. The magnitude of vibration and noise is uncertain, and there may or may not be.
The control methods of dust noise include: improving the cleaning method of bearing, and strictly cleaning the bearing, shaft, seat hole and matching parts before installation; Remove foreign matters in the lubricant; Improve the sealing of bearings; Avoid using plastic cages with impure materials or embedded foreign matters.
(3) Noise caused by lubrication factors and Its Countermeasures
Wrong lubricant selection, insufficient lubricant or aging hardening can lead to vibration and noise of bearings, and this noise has no certain law. In this case, only select the appropriate lubricant, adjust the amount of lubricant, prolong the service life of lubricant and reasonably determine the replacement cycle.
Noise related to main engine and Its Countermeasures
This kind of noise is not caused by the bearing alone, so it is futile to find the reason only from the bearing. We should pay full attention to the main engine and improve the performance of the main engine if necessary. This paper mainly describes the common buzzer sound and frame resonance sound in the motor.
(1) Buzzer of motor and Its Countermeasures
The axial vibration of the motor shaft will cause great high-frequency noise - buzzer, and its frequency is the same as the axial vibration frequency, which can be constant or variable. The method to prevent the buzzer is the same as that to prevent the axial vibration.
(2) Resonance sound of bearing frame and Its Countermeasures
When the axial bending natural vibration of the bearing frame is caused by the axial natural vibration of the outer ring mass system, a noise called resonant sound will be generated. The method of pre tightening can improve the axial natural frequency of the outer ring mass system, destroy the resonance condition and reduce the noise.