Bushings have multiple uses in the pump and seal business that include:

  • To thermally isolate a pumping liquid from the pump stuffing box
  • Located in the bottom of the stuffing box to stabilize a moving shaft.
  • In an API (American Petroleum Institute) gland to support the shaft in the event of a bearing failure.
  • To restrict the amount of flushing fluid flowing between the stuffing box and the rear of the impeller.

Most pump bushings are manufactured from carbon or Teflon®.

In recent years there have been many man made materials doing a good job of restricting fluid flow, reducing thermal conductivity, and reducing shaft radial movement in the stuffing box of centrifugal pumps.

The shaft to bushing clearance varies with the material, but 0.002"/ inch (0.002 mm/ mm) of shaft diameter is typical.



  • On February 14, 2018