To get the best performance from a rolling contact bearing, the fit between the inner ring and shaft, and outer ring and housing must be correct to make sure no movement between fitted surface during operation or under load.?
To prevent the creeping movement, bearing rings and the shaft or housing are installed with one of three types fit, include tight, transition and loose fitting.
Selection of a proper fit is dependent upon thorough analysis of bearing operating conditions, including consideration of:
1.The material, finishing, and strength of the shaft and housing
2.Bearing internal clearance
3.Mounting and dismounting methods
4.Machinery operating conditions (nature and magnitude of load, rotational speed, temperature°≠)
Following is recommendations:
(1) The interference should be tighterfor for heavy bearings load.
(2) The interference should be tighterfor for vibration and shock load conditions.
(3) In general, the larger of the beaing size the tighter of the interference.
(4) A tighter than normal fit should be given when the bearing is installed in hollow shafts or in housings
with thin walls.
(5) Tthe interference calculation needs to be considered the roughness of the mating surfaces.
(6) A tighter than normal fit should be given when the bearing is installed in housings made of light alloys
(7) Tthe interference calculation needs to be considered the loosening of the inner ring on shaft
due to temperature increases.