GRW High Precision Ball Bearings
Types of duplex assembly for radial ball bearings
High precision ball bearings in grades up to ABEC 9 with bores from 1 to 30mm and comparable inch dimensions
General Information
THREE TYPES OF DUPLEX ASSEMBLY FOR RADIAL BALL BEARINGS
Back to Back
O arrangement (DB)
(reference 1)
With the ‘back to back’ bearing pair the inner rings are claimed together. The contact angle lines between the outer ring raceway, ball and inner raceway diverge. This results in a maximum spread giving high rigidity. This is the reason why this type of duplex bearing is most commonly used.
Figure 21 – back to back
X arrangement (DF)
(reference 2)
With the ‘face to face’ bearing pair the outer rings are claimed together. The contact lines converge resulting in a smaller spread and more elastically.
Figure 22 – face to face
Tandem (DT)
(reference 3)
While duplex bearings mounted ‘back to back’ or ‘face to face’ are suitable to accommodate axial loading in both directions, a tandem mounted bearing pair is capable of accepting a very high axial load in one direction only. With this type of bearing pair, preloading and reduction of play can only be achieved, by preloading against another bearing or bearing pair.
Figure 23- tandem
