A containment seal chamber leakage collection system for condensing or mixed phase leakage on arrangement 2 unpressurized seals with containment seals.


  • This plan can be used with buffer gas (Plan 72) or without buffer gas (Plan 71).
  • Avoids direct leakage of pumped media to the atmosphere.
  • Liquid leakage is collected in the leakage collector and vapors pass to the collection system.
  • Excessive leakage and the use of an orifice in the outlet line of the collector together leads to a pressure build-up in the collector and triggers a pressure alarm at 0.7 bar (10 PSI) with the help of a pressure transmitter.

Recommended Application

Remarks, Checkpoints : 

  • Set the pressure transmitter alarm to a pressure of 0.7 bar (10 PSI) so as to trigger an alarm when the pressure in the leakage collector increases. This indicates inboard seal leakage.
  • Ensure that the vent line is always open and an orifice is present to generate back pressure.
  • Always mount the leakage collection system below the pump centerline.
  • Use sloping lines from the CSD port to the leakage collector.
  • Use the level gauge to ascertain if the leakage collector needs to be drained.

Recommended Application : 

  • For condensing media.
  • For configurations utilizing an outboard containment seal – contacting or non-contacting type.
  • Generally used in combination with a Plan 72 nitrogen purge.