Throttle bushings in the seal gland minimize the leakage leaving the seal gland and allows for detection of a seal failure.
Description
This plan incorporates throttle bushings in the seal glands that reduce leaking and also enables rapid detection of seal failure.
Application Notes
- Intended for use in Arrangement 1 applications where it is required to limit leakage in case of a seal failure or it is required to monitor excessive leakage.
- Leakage out of the drain port is collected and piped to a liquid recovery system or sump.
- As the leakage rate increases, the pressure will increase on the upstream side of the inner bushing which is in line with the pressure transmitter.
- Pressure in the drain cavity will be monitored by the pressure transmitter and can be used to monitor seal performance and trigger an alarm.
Pros:
- Drain cavity pressure can be used to monitor seal performance
Cons:
- The use of inappropriate process fluids may cause obstructions at inner bushings