API PLAN 74

Externally supplied barrier gas for arrangement 3 dual pressurized non-contacting gas seals.

Features

  • Nitrogen is used as barrier gas.
  • Pumped media never leaks to the atmosphere.
  • High reliability due to the absence of foreign particles/solids in the barrier gas.

Recommended Application

Remarks, Checkpoints : 

  • Check if nitrogen is compatible with the pumped media.
  • Ensure that the barrier gas pressure is higher than the seal chamber pressure by at least 1.7 bar (25 PSI).
  • Set the back pressure regulator at least 1.7 bar (25 PSI) above the seal chamber pressure.
  • Check filter from time to time for any blockages.
  • Do not use for polymerizing and sticky media as this creates problems with the inboard seal faces.
  • Ensure a reliable nitrogen supply. Avoid usage of nitrogen gas bottles.
  • Use individual gas panel per seal assembly in a between bearing pump.

 

Recommended Application :  

  • For dual pressurized non-contacting seals.
  • For media with moderate temperatures, with poor lubrication properties or with hazardous or toxic nature.
  • For services where media contamination is acceptable but no media leakage to atmosphere is tolerated.
  • Flashing light hydrocarbons.

Enquiry