CARB toroidal roller bearings can accommodate axial displacements of the shaft with respect to the housing within the bearing. The axial displacement can result from thermal expansion or deviations from determined bearing positions.
Misalignment as well as axial displacement influences the axial positions of the rollers in a CARB bearing. Axial displacement also reduces the radial clearance. SKF recommends checking that the axial displacement is within acceptable limits, i.e. the residual clearance is great enough, and that the rollers do not protrude outside the side face of a ring (fig 1a) or contact any locking ring (fig 1b) or seal. To accommodate the displacement of the roller and cage assembly, provide free space at both sides of the bearing as described in the section Free space at the sides of the bearing and indicated in fig 2.
The axial displacement from the normal position of one bearing ring in relation to the other is limited by
- the displacement of the roller set, or by
- the reduction of clearance.
The maximum possible axial displacement is obtained from the smaller of these two limitations.