Appropriate tolerance for shaft and housing for bearings?

[friscoboya]

Hello,

So I am designing a shaft which would involve bearings on the shaft, and a housing which would enclose the shaft. The shaft would be slightly bigger than the bearing hole which would create an interference fit so the bearings would stay on the shaft tightly. At the same time the bearing and shaft would be placed in a housing where the housing holes would be slightly smaller than the bearing outer diameter which would provide a tight fit so the bearings would stay in place. How would I determine the tolerance for the appropriate desired bearing stiffness? Below is a picture.

Thanks

 

[Baluncore]

It would be unwise to rely on a press fit to hold bearings in place. The bearings should be mounted by sliding them freely along a shaft until they are pressed gently onto a land that will locate them. Significant external or internal crush will change the diameter of the bearing running surfaces. If a retaining ring is not shrunk onto the shaft, a tube spacer should be used between bearings to prevent individual bearings moving along the shaft.

Spindle bearings are usually made from opposed pairs of angular contact ball or tapered roller bearings. The bearing cones can then be a hand fit on the shaft. Screw adjustment of the axial force on the bearings will then clamp the bearing position, while setting shaft alignment and preloading.

Your diagram seems to show three bearings on the shaft in the housing, why three and what type of bearings are they?
What size shaft and what RPM are you expecting.
Will the shaft bend when in use, or does it require maximum directional control by the bearing assembly?

See; https://www.gmnbt.com/downloads.htm

 

[jrmichler]

An excellent source for information is SKF.com. Their Bearing installation and maintenance guide is at http://www.skf.com/binary/tcm:12-114679/140-710 BIMG 11_2012_tcm_12-114679.pdf. It has a whole chapter on fits and tolerances.