Description: Plan 75 is a containment seal chamber which allows
draining of condensing leakage on Arrangement 2 dual seals. The
collection system is located below the seal chamber and uses an
orifice and a pressure transmitter to detect high vapor leak rates.
Typically used with contacting secondary containment seals.
Objective: Contain and vent leakage to collection system while
monitoring leak rate. Orifice sized to allow maximum leakage and
pressure alarm to shut down the pump if the leak rate is
excessive.
Advantages: Best for processes
that condense at ambient
temperatures. Can be used with
Plan 72 to sweep the leakage into
the containment system. Lower
cost and maintenance than dual
liquid systems.