Bearing failure analysis to improve the reliability of the working surface is an important part of system engineering. Bearings (bearings work functions in their specified loss, leading to failure or non-working, as a failure phenomenon is called (bearing failures can be divided into according to their normal Life failure and two early failures, this is mainly to analyze the reasons for the early failure of the bearing caused by pitting and fatigue and propose improvement suggestions to improve the life and reliability of SKF bearings.
SKF bearing fatigue failure is a form of failure surface, which is mainly manifested in the initiation, propagation and fracture process of fatigue cracks, and the long-term effects of load failures generated by the alternate metal. The cracks are in two aspects:
1. From the surface, this is the effect of external load caused by the plastic deformation on the working surface and the periodic change of the contact stress on the strain-hardened surface during the rolling contact process of the SKF bearing, and finally the small cracks develop from The inner surface, the formation of a crack in the surface between the two, due to the penetration of lubricant on the work surface, the opening force, severely hit the wall, forcing the crack to advance;
2. From the surface layer, under repeated pressure, surface contact, initial cracks are generated at a certain depth where the surface is exposed, and the angle along the surface direction, to a certain depth, from behind the surface of the contact surface, and beyond The surface, and eventually formed etch and peel, leaving a pit.
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On the surface, it is still from the cracks in the surface layer. These two goals (parts carburizing, quenching and other surface heat treatment, afterwards, if there are uneven hardness, structure, and non-uniform internal stress and other disadvantages, the contact stress is normal Under the influence of the opposite underground cracks, if the surface quality of the parts is poor, there is a defect (oxidation, decarburization), poor friction or lubrication, and cracks from the surface.
The role of the SKF imported bearing is to make the stationary ring and rotating ring of the SKF imported bearing solidify with the stationary part (usually the SKF imported bearing seat) and the rotating part (usually the shaft) of the installation part, so as to realize the rotating state The basic tasks of transferring loads and defining the position of the moving system relative to the stationary system. On the shaft and in the SKF imported bearing seat, the rolling SKF imported bearing is required to fix its position in the radial, axial and tangential directions. Radial and tangential positioning are achieved by the tight fit of SKF imported bearing rings. Axial positioning only uses tight fit in a few cases; generally, axial limiting parts, such as end caps and retaining rings, are used for axial positioning. The position is limited to the clearance range. The following 4 points should be paid attention to when choosing cooperation:
1. The circumferential surface of the SKF imported bearing ring should have good support and uniform force to reduce deformation and give full play to the carrying capacity of the SKF imported bearing.
2. The ferrule cannot slide along the tangential direction in its mating appearance, otherwise the mating surface will be damaged.
3. Attention must be paid to make SKF imported bearing installation and disassembly simple, saving labor, time and expenditure.
4. The free-end SKF imported bearing must be able to adapt to the change in the length of the shaft and the SKF imported bearing seat hole, that is, it must have a device that can adapt to the axial position to move within a certain range ability.
In addition to excellent quality, SKF imported bearings are also very precise parts. They are high-performance SKF imported bearings. If they are used improperly, they will not only fail to achieve the expected performance results, but also easily damage the SKF imported bearings. Everyone must have paid attention to lubrication. In addition to lubrication, what other aspects should be paid attention to during the use of SKF imported bearings?
1. Be careful when using and installing
2. Use appropriate and accurate installation tools
3. Try to keep the SKF imported bearings and the surrounding environment clean
4. Prevent the corrosion of SKF imported bearings