Design of bearing arrangements

Abutment dimensions

The support surfaces in housings and on shafts should be at right angles to the shaft axis and provide uninterrupted support over the entire washer face. The abutment diameter on the shaft should be ≥ da min and in the housing ≤ Da max (fig. 1). Values for da min and Da max are listed in the product tables.
To provide satisfactory radial guidance for the individual thrust bearing components, suitable tolerance classes for shafts and housings are listed in table 1. A radial gap between the shaft and washer bore is required for housing centred washers. Shaft centred washers require a radial gap between the washer and housing bore.
Cylindrical roller and cage thrust assemblies are generally centred radially by the shaft, to reduce the circumferential speed at which the cage slides against the guiding surface. This is particularly important for higher speed applications. The guiding surface should be ground.

Raceways on shafts and in housings

If the load carrying capacity of a cylindrical roller and cage thrust assembly is to be fully exploited, the raceways on the shaft or in the housing should have the same hardness, surface finish and axial run-out as a bearing washer.
The dimensions Ea and Eb (→ product tables) take the possible displacement of the roller set into consideration and should be applied when designing raceways on shafts and in housings.
For additional information, refer to Raceways on shafts and in housings.
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