Bearings with a tapered bore
Bearings with a tapered bore can be mounted directly on tapered shaft seats, or on adapter or withdrawal sleeves (fig. 1, fig. 2, fig. 3 and fig. 4). Sleeves that are fitted to cylindrical shaft seats have an external taper. Whether the bearing is mounted on a sleeve or directly on the shaft, the fit of the bearing inner ring is not pre-determined by the bearing seat, as is the case for bearings with a cylindrical bore. Instead, the fit for bearings with a tapered bore is determined by the distance through which the ring is driven up on its tapered seat or on the sleeve. Special precautions relative to the internal clearance reduction must be considered as mentioned under Bearing clearance and under Self-aligning ball bearings, Spherical roller bearings, and CARB toroidal roller bearings.
If the bearings are to be mounted on an adapter or withdrawal sleeve, larger diameter tolerances are permitted for the sleeve seat, but the tolerances for total radial run-out must be tighter (→ Dimensional and geometrical tolerances of bearing seats and abutments).