Plan 32

Description:
Injection of external source of liquid into the seal chamber
Features:
- Reduce flashing or air intrusion across seal faces
- Can maintain vapor point margin
- Must be provided at pressure higher than the seal chamber pressure
- Provides the best seal environment of all single seal plans
For use:
- Dirty or contaminated fluids
- High temperature applications
- Polymerizing and oxidizing fluids
- Media with poor lubricating properties
Caution:
- External source must be continuous and reliable, even during start up and shut down
- Flush fluid must be compatible with process fluid and should not vaporize at process temperature
- Product dilution will occur
- Use with close clearance throat bushing to maintain pressure and reduce flush flow
- Understand the cost of flush fluid, several gallons per minute consumption is typical