Matching and Pretightening Technology of Angular Contact Bearings

Time：2020.09.03  Source：Roller Bearings Suppliers

Under normal circumstances, the group of supporting contact ball bearing contact Angle is the same,When the axial load exceeds the rated requirement, some bearings will be unloaded, which will cause the ball to slip and cause early bearing failure.

In order to avoid the unloading phenomenon (i.e., to improve the unloading force), the pre-load of the bearing group can be increased or the bearings with different contact angles can be combined.

In order to meet the bearing capacity and stiffness requirements, the angular contact ball bearing can be combined in a variety of ways in the process of use. In order to maximize the performance of the combined bearing under specific working conditions, it is very important to select the appropriate preload.Correct preload can not only increase stiffness, but also reduce noise, improve shaft guidance accuracy, extend bearing service life, improve rotation accuracy, and prevent the occurrence of skidding and other phenomena in high-speed application of fast start/stop, ultra-light load or empty load.Need WSBC 22216-E1,click here to learn more.

1. Matching mode of angular contact bearings

Bearings with different contact angles have the same matching mode with bearings with the same contact Angle. According to the number of matching bearings, the matching mode can be divided into double, triple and quadruple.The bearings can be classified according to the direction of the assembly.Different contact Angle bearings are mainly composed of DB,TBT,QBC and DBT types.

2. Pretighten the angular contact bearing

Axial preloading is usually used in the use of angular contact ball bearings, and there are two ways of preloading: positioning preloading and constant pressure preloading.

Positioning preloading: The spacing of the combined bearing or the preset inner and outer ring spacer is kept constant, so that the bearing can be properly preloaded. 

Due to the influence of the working state and external environment of the bearing, the bearing seat size and bearing parts will also change accordingly, thus affecting the preloading state of the bearing.The preloading method is beneficial to improve the rigidity of the bearing, but the influence of the preloading on the bearing performance should be paid attention to.

Constant pressure preloading: is the use of spiral spring, butterfly spring and other elastic components, so that the bearing in the support to get the appropriate preloading.With constant pressure preloading, the movement of the bearing under normal working conditions will not affect the preload, but the stiffness class of the bearing is low, so it is suitable for high-speed rotating occasions, but not suitable for bearing applications requiring high stiffness, bearing direction change or uncertain impact load may occur.Click here to learn more about WSBC 22219-E1.

3. Influence of external load on axial displacement of preloaded bearing group

For the bearings, the preload is more easily affected by the external load.

1) Angular contact ball bearings can be matched not only with bearings with the same contact Angle, but also with bearings with different contact angles, and there are various ways of matching.

2) Compared with the bearings with the same contact Angle, the bearing capacity of the main bearing end can be enhanced by using different contact Angle bearings under the same preloading force and matching mode.

3) When bearings with different contact angles are used for assembly, the bearing group's non-main bearing end has relatively low bearing capacity, so orientation should be paid attention to in the use process.