FB and FR Technical Notes

Bearing Clearance

Diametrical clearance for FB and FR self-lubricated bearings are based on a relatively rigid housing material. Under these conditions the resulting shaft/bearing clearance will be optimal. For thin-walled housings or non-rigid housing materials, there may be housing expansion. Consult your PEER Representative for further details.

Installed ID

The installed ID of a PEER FB/FR bearings is equal to the housing bore diameter minus twice the bushing wall thickness. Therefore, the installed ID tolerance is equal to the housing bore tolerance minus twice the wall thickness tolerance.

Standard PEER FB/FR bearings are held to the closest tolerances in the industry. If needed, special higher tolerance bearings are available. Consult PEER for more details.




Shaft Surfaces and Finish

Shafts used with the PEER FB/FR bearings should be finished to 0.8 µm AA (32 µi AA) or better. For those demanding applications where a mixed film or hydrodynamic lubrication is found, shafts used with the PEER FR bearings should be finished to 0.4 µm (16 µi AA) or better.

Shaft surface finish should be turned in the direction of the service rotation, ground in the opposite direction, and then polished in the service direction for optimal performance.

Lubrication

The PEER FB is optimized to run dry, without any lubrication. However, the FB will give excellent performance in a wide variety of lubricated environments.

The PEER FR is specifically designed to run in any kind of fluid environment, including all hydraulic oils and methanol. For demanding applications oil grooves may be embossed or machined into the bearing surface. Oil grooves aid in oil delivery and allow for better cooling in severe conditions. Also the location of the oil groove with respect of the load zone and split line is very important. Typically the groove location should be positioned 25°- 45° from the load zone or split line is recommended.


General Notes
  • Do not bore or grind the inner or outer face of the bushing. The PEER FB/FR is a finished product requiring no further surface preparation. Boring the inner face will cause the removal of the PTFE-coated layer, reducing life. Grinding the outer face may allow rust to form and distort roundness.

  • The bearing is designed so that the split or mating gap will be eliminated upon insertion of the bearing into the housing. However, the split should be positioned away from the main load zone.

    Fit the bearing slowly and concentrically into the housing using a press or vice. Bearing configurations are shown in Drawing 1, and the optimally-sized arbor for installation is shown in Drawing 2.

  • Because the OD of the bearing is greater than the housing ID, and because the FB/FR has a steel back of high mechanical strength, the FB/FR will never turn or spin out. Resin molded bearings, without a steel back, tend to deteriorate through creeping.









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