Preload & Duplex Ball Bearings

Preloading of Angular Contact Ball Bearings and Implementing in a Duplex Bearing Set Can Result in Increased Bearing Performance

Face-to-Face: Face-to-face, or DF, is a duplex arrangement where ACCB contact angles converge toward the bearing axis. DF bearing sets are less sensitive to misalignment, but they’re not as stiff under moment loading as back-to-back (DB) bearing sets. The permissible load directions are radial, axial (both directions), and moment. The stiffness is good for moment loads, and very good for radial and axial loads.
Back-to-Back: Back-to-back, or DB, is a duplex arrangement where ACCB contact angles diverge from the bearing axis. DB bearing sets are stiffer under moment loading than DF bearings sets but are more sensitive to misalignment. The permissible load directions are radial, axial (both), and moment. For all three types of loads, the stiffness is very good.
Tandem: In this configuration, the bearings are installed with the openings facing in the same direction (wide to narrow) as the image below shows.
Universal: This is a singular (non-duplex) installation and is shown for reference.
Custom: Finally, preloaded angular contact bearings can use a custom configuration in any set configuration or combination of configurations. They can also be paired with spacer sets. Custom configurations can be designed to optimize performance for a specific application, and both the permissible load directions and the stiffness depend upon the arrangement.