The gland is the part that holds the stationary half of the mechanical seal and attaches to the stuffing box.


The above drawing shows the stuffing box bolting to the back plate. In most designs the stuffing box is cast as a part of the back plate.

There are a number of seal gland designs that include:

  • The API (American Petroleum Institute) gland for refinery service and any time you are pumping dangerous products. Although expensive this is also an excellent gland to use for packing conversion because in the event of a bearing failure the shaft will hit the disaster bushing in the gland and prevent a major destruction of the mechanical seal.
  • Flushing gland:
    • To introduce clean liquid into the stuffing box.
    • To connect to the pump discharge to pressurize the fluid in the stuffing box and prevent product vaporization or flashing.
    • To vent the stuffing box in a vertical pump installation.
    • To connect to the suction piping and circulate fluid behind the impeller into and out of the stuffing box for cooling purposes.
  • Quenching gland:
    • To introduce steam behind the seal for heating purposes and to keep atmosphere away from outboard the seal.
    • When used with a disaster bushing it will direct leakage to a flare where the leakage can be burned or directed to a tank where it can be collected.



  • On February 15, 2018