Vent for non-condensing leakage with a contacting containment seal.
Description
Plan 76 seal monitoring systems divert non-condensing leakage from primary seals to a flare or vapor recovery system.
Application Notes
- Typically used on Arrangement 2 unpressurized dual seals, which also utilize a dry running containment seal.
- Used if the pumped fluid does not condense at ambient temperatures.
- Ensure condensate drain is at a low point.
- Ensure vent line is open and orifice is present to generate back pressure.
- May be used with a buffer gas (Plan 72) or without a buffer gas (Plan 71).
- Lower initial/maintenance cost than dual unpressurized seals using Plan 52 by eliminating sometimes costly support systems.
- Leakage from inner seal is contained and vented safely.
Pros:
- Low installation and maintenance costs
- Safe containment and venting of inner seal leakages
Cons:
- Accumulation of liquid within the seal chamber will generate heat and damage seal system
- Some primary seal leakage may escape into the atmosphere