When angular contact thrust ball bearings operate at high speeds, the centrifugal forces and gyratory moments acting on the balls may cause them to slide on the raceways. To prevent the damaging consequences of this, for example smearing, the bearing must always be subjected to a given axial load.
The requisite minimum axial load to be applied to single direction angular contact thrust ball bearings can be obtained from
|Fam||=||minimum axial load [kN]|
|A||=||minimum load factor (see product data)|
|n||=||rotational speed [r/min]|
When starting up at low temperatures or when the lubricant is highly viscous, even greater loads may be required. The weights of the components supported by the bearing, together with the external forces, generally exceed the requisite minimum load. The double direction angular contact ball bearings are preloaded by adjusting the two shaft washers against each other.