Designs and variants

The ready-to-mount, greased and sealed ball bearing units are available in wide variety of designs and variants with main differences in housing shape and material, as well as the Insert bearings they incorporate.


Some frequently used bearing (unit) terms are explained here. Essentially, these terms are in accordance with those in the following ISO standards:
  • ISO 3228:2013 Rolling bearings – Cast and pressed housings for insert bearings
  • ISO 9628:2006 including Amd.1:2011 Rolling bearings – Insert bearings and eccentric locking collars
A detailed collection of bearing specific terms and definitions are also listed in ISO 5593:1997 Rolling bearings – Vocabulary.
Insert bearings
Insert bearings, wide inner ring bearings (fig. 5, fig. 6, fig. 7, fig. 8, fig. 9)
  1. Outer ring
  2. Sphered outside surface
  3. Lubrication hole
  4. Inner ring
  5. Bore
  6. Cage
  7. Ball
  8. Integral seal
  9. Flinger
  10. Eccentric locking collar
  11. Grub (set) screw
  12. Stepped sleeve
  13. Mounting collar
  14. Adapter sleeve including lock nut and lock washer
Ball bearing units
Ball bearing plummer (pillow) block unit (fig. 10)
  1. Insert bearings plummer block housing
  2. Housing base
  3. Housing support face
  4. Cast dimple for dowel pin
  5. Attachment bolt hole
  6. Insert bearing
  7. Grease fitting
  8. Recess for end cover
  9. Fitting slot for insert bearing
Ball bearing flanged unit (fig. 11)
  1. Square flanged housing
  2. Attachment bolt hole
  3. Back of flanged housing with or without centring recess
  4. Cast dimple for dowel pin
  5. Insert bearing
  6. Grease fitting
  7. Fitting slot for insert bearing
  8. Recess for end cover
Ball bearing take-up unit (fig. 12)
  1. Take-up housing
  2. Grease fitting
  3. Insert bearing
  4. Piloting groove
  5. Recess for end cover
  6. Receiving opening for adjustment screw location
  7. Centre bore for adjustment screw
  8. Fitting slot for insert bearing
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