Table 2:Types and Features of Matched Angular Contact Ball Bearings

Figure Arrangement Features
Back-to-back Back-to-back
(DB)
(Example)
7208 A DB

Radial loads and axial loads in both directions can be sustained.

Since the distance between the effective load centers a0 is big, this type is suitable if moments are applied.

Face-to-face Face-to-face
(DF)
(Example)
7208 B DF

Radial loads and axial loads in both directions can be sustained.

Compared with the DB Type, the distance between the effective load centers is small, so the capacity to sustain moments is inferior to the DB Type.

Tandem Tandem
(DT)
(Example)
7208 A DT

Radial loads and axial loads in one direction can be sustained. Since two bearings share the axial load, this arrangement is used when the load in one direction is heavy.