1, Tolerance grade

And bearing with the tolerance level of the shaft or housing bore and bearing accuracy related. With P0 class precision bearing with the shaft, the tolerance level is generally IT6, bearing hole is generally IT7. Rotating accuracy and smooth operation with higher requirements of the occasion (such as electric motors, etc.) should be selected axis IT5, bearing hole is IT6.

2, With the choice of tolerance
Equivalent radial load P into "light" situations "normal" and "heavy" load, etc., with the bearing dynamic load rating C is the relationship of:
Light load P≤0.06C normal load 0.06C <P≤0.12C heavy load 0.12C <P

1) Shaft tolerance

Mounting tolerances radial bearings and angular contact bearings the shaft tolerance zone with reference to the corresponding table. For most occasions, the axis of rotation and a radial load direction unchanged, that load bearing inner ring with respect to the direction of rotation of the occasion, the general should choose a transition or interference fit. Stationary shaft and radial load direction unchanged, that the bearing inner ring with respect to the load direction is static, choose a transition or a small clearance fit (too much space is not allowed).

2) Housing bore tolerance zone

Install radial bearings and angular contact bearings with reference to the corresponding housing bore tolerance tolerance zone table. Note the load direction oscillating or rotating the outer ring of choice, avoid clearance fit. Equivalent radial load size can also affect the selection with the outer ring.

3) Bearing structure in the form of seat selection

Rolling bearing unless there are special needs, and more generally with the overall structure, split bearing only the mounting difficulties, or the advantages of easy assembly on to become main consideration when used, but it does not apply tight fit or a more precise fit, for example, than K7 K7 and tighter fit, and if tolerance class IT6 or more sophisticated housing bore, shall adopt split housings.