A piece of auxiliary equipment is failing

The convection tank used with dual seals.

  • It is running backwards. There are multiple causes for this problem:
    • The inlet and outlet ports are not drilled properly. Centrifugal force is working against convection.
    • cartridge dual seal has not been centered properly.
    • Connections have been made to the wrong fittings.
    • The piping fitting has bottomed into the gland shutting off or restricting the flow.
  • The pressure or level in the tank changes.
    • Temperature change of the barrier or buffer fluid.
    • No air pocket was left in the top of the tank.
    • One of the seals is leaking. The pressure or level change should tell you which one. If the inboard seal is leaking the level will increase. An outboard seal leak will cause the tank level to drop or empty completely.
  • The level in the tank drops a little and then holds.
    • The outboard seal is leaking. Without a vent on the top of the convection tank the dropping fluid level created a vacuum in the tank stopping the level at a new height. This is similar to the level you can hold in a drinking straw if you keep your finger on one end of the straw.
  • The convection tank is not convecting at all. The tank was installed incorrectly. The minimum and maximum dimensions for the pipe locations were ignored.

Flow meter not indicating.

  • The meter is broke.
  • Line clogged.
  • The flow is not high enough.
  • The gauge graduations are too large for the desired flow. Operators like to operate in the center of gauges

No flow through the quench and drain connections.

  • You’re piped to the wrong connection. Most glands that have been drilled for a quench connection, have a flush connection also.
  • Valve not open.
  • Line clogged.
  • Operators love to shut this quench connection off to stop what they think is a seal leak.

Loss of jacket cooling. The incoming and out going lines are at the same temperature.

  • A layer of calcium has built up on the inside of the cooling jacket. This is the problem with using shop water as a coolant. You’d be better off using steam or condensate to heat or cool stuffing box jackets
  • A discharge recirculation line is connected to the stuffing box (it may be hidden inside the insulation and no one can see it).
  • Someone has shut off the cooling water or steam.


  • On February 18, 2018