The backing bearings based on cylindrical roller bearings have two or three rows of rollers and are available as full complement bearings (without cage) or as caged bearings, with or without integral flanges or flange rings. The advantage of the bearings without flanges lies in their particularly simple geometrical form and their very high radial load carrying capacity.
Cylindrical roller backing bearings without flanges or flange rings cannot accommodate any axial load. It is therefore necessary to position thrust washers of bronze or plastic between the side faces of the outer ring and the support saddles.

Thrust washers are not required with backing bearings with flanges (or flange rings) as the design of these bearings enables them to accommodate simultaneously acting radial and axial forces.

On each backing shaft of a cluster mill, several bearings are installed side by side. With their outside diameter surface in direct contact with the intermediate rolls, these bearings rotate while carrying components of rolling force. Therefore, the outer rings of these bearings are required to have adequate rigidity and fatigue strength, and should be finished with high precision.