API Plan 53B Barrier Fluid Pressurized by Bladder Accumulator
API Plan 53B circulates a pressurized barrier fluid between the inboard and outboard seals. The source of pressurization is a bladder accumulator. Plan 53B has the advantage of not allowing gas absorption into the barrier fluid which may allow for operation at higher pressures than Plan 53A. Barrier fluid pressure should be monitored as an indicator of seal leakage. Barrier fluid will leak across the inboard seal face and pass into the process. For this reason, the barrier fluid must be chemically compatible with the process fluid and process dilution not a concern. In order to provide positive circulation through the support system and into the seal, a pumping ring is employed. Heat removal is achieved by using a heat exchanger.
This plan:
- Attains a higher barrier fluid pressure with the use of a pressurized bladder accumulator
- Provides additional heat removal from inboard seal when required
Plan 53B is available as an assembly. The associated field installation kit for use in connecting the assembly to your system is also available. Assembly contents may include:
- Swagelok tube fittings
- 63 series ball valves
- V series 2-valve manifold
- QTM series quick-connects
- PGI series gauges
- TTW series thermowell tee
- Swagelok pipe fittings
- Pressure transmitter
- Temperature transmitter
- Bladder accumulator
- Permanent gauge head
- Heat exchanger
See page 39 of the Mechanical Seal Support Systems Application Guide for additional details and ordering information. Contact your authorized Swagelok sales and service center for information on optional components.