Damage prevention and maintenance Through the fault and […]
Damage prevention and maintenance
Through the fault and deterioration of the bearing, the performance state parameters to judge and predict the reliability and performance of the bearing, identify and judge the location, cause and degree of the abnormal situation, and determine the comprehensive technology of repair and improvement methods. Therefore, the fault diagnosis technology of the bearing is not a simple fault detection (or monitoring) technology, nor is it a simple inspection instrumentation. Acquire signals correctly, quickly and efficiently, data processing, manual or automatic identification and judgment. In order to determine the scientific repair cycle, the necessary tests and estimates of fatigue and wear life should be performed according to the mechanism of various failures. Bearing fatigue failure is a failure of the surface form, mainly manifested by fatigue crack initiation, expansion and fracture processes, and the long-term effects of load failure on the metal. The crack is in two ways.
1, from the surface
This is the effect of the external load caused by the periodic deformation of the contact between the plastic deformation of the working surface and the contact stress of the strain hardened surface during the rolling contact, and finally at the inner surface of the small crack from the development, between the two The formation of surface cracks, due to the intrusion of lubricant into the working surface, the open force, severely hitting the wall, forcing the crack to advance.
2, from the surface layer, under repeated pressure
The contact of the surface, initially at the surface where the surface is exposed, cracks at a certain depth, and the angle along the surface direction, to a certain depth, from the surface of the contact surface, and beyond the surface, and finally form an etch strip, leaving a Horse pit. From the surface of the bearing, or from the cracks in the surface layer, these two objectives (parts carburizing, quenching and other surface heat treatment, if there is uneven hardness, microstructure, and non-uniform internal stress and other unfavorable, contact stress Generally, from the influence of the opposite underground crack, if the surface quality of the part is poor, there is a defect (oxidation, decarburization), friction or poor lubrication, and crack from the surface. The method of controlling the rolling sound is: selecting a low noise bearing For bearings with small waviness, the conditions of use are carefully selected. The sound of the raceway often affects the noise of the whole machine, and the noise of the raceway can reduce the noise of the whole machine.