Single direction tapered roller thrust bearings

The small single direction tapered roller thrust bearings are used almost exclusively for the kingpin bearing arrangement of commercial vehicles,They have a full complement of rollers and are held together by a sheet steel cover . Most of these bearings are fitted with rubbing seals of wear and oil-resistant nitrile (NBR) rubber.

They are lubricated for life with a multi-purpose grease and require no maintenance. There are several designs which differ only in the design of the housing washer and the cover.

The washers of the bearings with shaft and housing washers having the same dimensions both have a tapered raceway and one retaining flange. Bearings of this design are to be preferred where very heavy axial loads are to be supported as, for example, in the swivels of drilling rigs or in crane hooks. The bearings have a cage which is centred on both washers.

In spherical roller thrust bearings the load is transmitted from one raceway to the other at an angle to the bearing axis. The bearings are therefore suitable to accommodate radial loads in addition to simultaneously acting axial loads. Another important characteristic of spherical roller thrust bearings is their self-aligning capability. This makes the bearings insensitive to shaft deflection and misalignment of the shaft relative to the housing.

Single direction tapered roller thrust bearings incorporate a large number of asymmetrical rollers and have specially designed raceways with an optimum conformity. They can therefore support very heavy axial loads and permit relatively high speed operation.

Single direction tapered roller thrust bearings are produced in two designs depending on the size and series. Bearings up to and including size 68 identified by the designation suffix E have a pressed steel window-type cage which, with the rollers, forms a non-separable assembly with the shaft washer. All other bearings have a machined brass or steel cage which is guided by a sleeve held in the shaft washer bore. The shaft washer and cage with rollers form a non-separable unit.