70 .. E series

• Values for the inner ring and thrust side of the outer ring: ISO 15

• Values for the non-thrust side of the outer ring: ISO 12044

 

DB Suffix:Back-to-back arrangement Designation

DF:Face-to-face arrangement Designation

DT:Tandem arrangement Designation

TBT: Back-to-back and tandem arrangement Designation

TFT: Face-to-face and tandem arrangement Designation

TT: Tandem arrangement Designation

QBC:Tandem back-to-back arrangement Designation

QFC: Tandem face-to-face arrangement Designation

QT:Tandem arrangement Designation

QBT:Back-to-back and tandem arrangement Designation

QFT: Face-to-face and tandem arrangement Designation

Back-to-back arrangement
In a back-to-back arrangement († fig. 11), the load lines diverge along the bearing axis.
Axial loads acting in both directions can be accommodated, but only by one bearing or
bearing set in each direction.
Bearings mounted back-to-back provide a relatively rigid bearing arrangement. The wide
span between bearing effective centres makes this arrangement particularly well suited to
support moment loads.
Face-to-face arrangement
In a face-to-face arrangement († fig. 12), the load lines converge along the bearing axis.
Axial loads acting in both directions can be accommodated, but only by one bearing or
bearing set in each direction.The short span between effective bearing
centres makes face-to-face arrangements less suitable to support moment loads.
Tandem arrangement
The use of a tandem arrangement provides increased axial and radial load carrying capacity compared to a single bearing. In a tandem arrangement († fig. 13), the load lines are
parallel so that radial and axial loads are shared.
The bearing set can only accommodate axial loads acting in one direction. If axial loads act
in both directions, or if combined loads are present, additional bearing(s) adjusted against
the tandem arrangement must be added.

 

V-shaped” marking

A “V-shaped” marking on the outside surface

of the outer rings of matched bearing sets indicates how the bearings should be mounted to obtain the proper preload in the set.

The marking also indicates how the bearing set should be mounted in relation to the axial

load. The “V-shaped” marking should point in the direction that the axial load acts on the

inner ring († fig. 16). In applications where there are axial loads in both directions, the

“V-shaped” marking should point in the direction of the heavier of the two loads.