Common Failure Modes And Countermeasures Of Spark Rolling Bearings

Time：2020.05.20  Source：Roller Bearings Suppliers

The correct and reasonable use of bearings is a systematic project. In the process of bearing structure design, manufacturing and installation, corresponding measures are taken for the links that produce early failures, which can effectively increase the service life of bearings and the host.

1. Peeling from the extreme position of one side of the channel

The spalling at the extreme position of one side of the channel is mainly manifested in the severe spalling ring at the junction of the channel and the rib. The cause is that the bearing is not installed properly or the axial overload occurs suddenly during operation.

The countermeasures taken are to ensure that the bearing is installed in place or to change the fit of the outer ring of the free-side bearing to a clearance fit in order to compensate the bearing when the bearing is overloaded. If the installation cannot be ensured in place, you can increase the thickness of the lubricant film (increasing the viscosity of the lubricating oil), or reduce the bearing load to reduce the direct contact of the bearing.Need WSBC Bearing 6302,click here.

2. The channel peels off in a symmetrical position in the circumferential direction

Peeling in symmetrical position means that the inner ring is peeling off from the surrounding annulus, while the outer ring is peeling in a circumferentially symmetrical position (that is, the short axis direction of the ellipse). It is particularly evident in camshaft bearings for motorcycles. When the bearing is pressed into the housing hole with a large ellipse or the two-half split housing is tightened, the outer ring of the bearing produces an ellipse, and the clearance in the short axis direction is significantly reduced or even negative. Under the effect of the load, the inner ring rotates to produce circumferential peeling marks, and the outer ring only produces peeling marks at symmetrical positions in the short axis direction. This is the main reason for the early failure of the bearing. Examination of the failed parts of the bearing shows that the outer diameter roundness of the bearing has changed from 0.8um controlled by the original process to 27um. This value is much larger than the radial clearance value. Therefore, it can be affirmed that the bearing is working under severe deformation and negative clearance, and abnormal sharp wear and peeling are likely to form early on the working surface.

The countermeasures adopted are to improve the processing accuracy of the shell hole or to avoid the separation structure of the shell hole halves as much as possible.

3. The raceway inclines and peels off

The inclined peeling ring belt on the working surface of the bearing shows that the bearing works in a tilted state. When the tilt angle reaches or exceeds the critical state, it is easy to form abnormal sharp wear and peeling at an early stage. The main reason is that the installation is poor, the shaft has deflection, and the precision of the journal and the housing hole is low.

Take measures to ensure the quality of bearing installation and improve the axial runout accuracy of shaft shoulder and hole shoulder, or increase the viscosity of lubricating oil to obtain a thicker lubricating film.

4. Ferrule break

The failure of ferrule fracture is relatively rare, usually caused by sudden overload. The causes are more complicated, such as bearing raw material defects (bubble shrinkage), forging defects (overburning), heat treatment defects (overheating), processing defects (local burns or surface micro cracks), host defects (poor installation, poor lubrication, instant Overload) etc. The ferrule may break due to overload shock load or severe vibration.

The countermeasures adopted are to avoid overload impact load, choose appropriate interference, improve installation accuracy, improve service conditions and strengthen quality control in the bearing manufacturing process.Click here to know more about WSBC 23232CC/W33.

5. Stuck

The seizure is a surface damage caused by a combination of minute burns on the sliding surface. Linear scars on the circumferential surface of the slide surface and rolling surface. The trochoidal scars on the end surface of the roller, and the collar surface near the end surface of the roller are stuck. The main causes of stuck injuries are: excessive load, excessive preload, poor lubrication, biting of foreign objects, tilti.ng of the inner ring and outer ring, shaft deflection, poor accuracy of the shaft and bearing box, etc.

It can be solved by proper preloading, improving lubricants and lubrication methods, and improving the accuracy of shafts and bearing boxes.

Wuxi Spark Bearing Co.,Ltd provide various kinds of High-Qality Bearings.We have more than ten years of export experience.Many foreign customers are very satisfied with our products.