Thrust ball bearings

SKF thrust ball bearings are produced as single direction or double direction thrust ball bearings. They are designed to accommodate axial loads only and must not be subjected to any radial load.
SKF thrust ball bearings are separable, i.e. the shaft washer, housing washer(s), ball and cage assembly(s) can be mounted separately. Shaft washers have a ground bore to enable an interference fit. The bore of the housing washer is turned and always larger than the shaft washer bore.

Single direction thrust ball bearings

single direction thrust ball bearings
Single direction thrust ball bearing
SKF single direction thrust ball bearings consist of a shaft washer, a housing washer and a ball and cage assembly (fig 1). As their name implies, single direction thrust ball bearings can accommodate axial loads and locate a shaft axially, in one direction only.

Double direction thrust ball bearings

Double direction thrust ball bearings
Double direction thrust ball bearing
SKF double direction thrust ball bearings consist of one shaft washer, two housing washers and two ball and cage assemblies (fig 2).
The housing washers and ball and cage assemblies are identical to those found in single direction bearings. Double direction thrust ball bearings can accommodate axial loads and locate a shaft axially, in both directions.

Thrust ball bearings with sphered housing washers

Double direction thrust ball bearing with sphered housing washers
To accommodate initial misalignment between the shaft and housing, SKF supplies both single and double direction thrust ball bearings with sphered seat surfaces on the housing washers (fig 3). They can be used together with a sphered seat washer adjacent to the housing washer (fig 4 and fig 5) or adjacent to a machine component manufactured with a sphered surface.
Appropriate sphered seat washers must be ordered separately.
Depending on the bearing series, they have the basic designation U 2, U 3 or U 4 followed by a two-digit number, which identifies the size (e.g. sphered seat washer U 320 for bearing 53320).