You placeHome-the media-facing information
the media-facing information Time:18/02/01 [Back] The basic principle of select bearing’s fits

1.      The status of bearing rings relative to the load.

For ring that rotates or swings in load direction, it should choose interference fit.

For rings that fixed in load direction, it should choose loose fit.

When Non-separable bearing is used as a traveling support, the travel ring should be use a fixed ring relative to the load direction, and it should choose loose fit or transition fit.

2.      The type and size of the load.

When bearing shock load or heavy-load, we choose a more tight fit than normal and light load. The load value of DHK bearing is distinguished by the ratio of dynamic equivalent radial load Pr and dynamic radial load rating Cr. The bigger load should choose the bigger interference.

3.      The size of bearing dimension.

With the increase of bearing dimension, have the bigger interference value of interference fit and the bigger clearance value of loose fit.

4.      Bearing clearance.

Interference fit will reduce the clearance of DHK bearings. We need check whether the clearance of the bearings after installation is able to meet the application requirement, so to select the correct fit and original bearing clearance.

5. The influence of other factors. The material, strength and thermal conductivity of shaft and bearing seat, the heat conduction way and heat from outside or generated in the bearing, and the installation and adjustment performance of the bearing, all above will affect the selection of the tolerance zone.

6. The select of tolerance grade. The tolerance class of the shaft or housing hole that in conjunction with the DHK bearing is related to the bearing’s tolerance. The shaft fit with PN, P6 (P6x) tolerance class bearing is generally with tolerance IT6, and the housing hole is generally with tolerance IT7. For high requirement of rotation accuracy and running stability, not only need improving the bearing tolerance class, the fit position of bearing should also be improved according to the corresponding precision.

Copyright Ningbo DHK Precision Bearing Co., Ltd. All right