Recirculation from pump discharge through a flow control orifice to the seal chamber and from the seal chamber through a flow control orifice to pump suction.
Description
This plan is a combination of Plan 11 and Plan 13 where process fluid is recirculated from the pump discharge through a control orifice, and from the seal chamber through a flow control orifice to the pump suction.
Application Notes
- Combination of Plan 11 and Plan 13.
- Most commonly used on vertical pumps.
- Acts to optimize cooling and continuous venting of the seal chamber. Vent must be at a high point.
- Flush is directed onto the seal faces.
- Can help to raise the pressure in the seal chamber.
Pros:
- Optimizes cooling and seal chamber venting
- Flush is targeted directly at seal faces
- Might help to raise seal chamber pressure and control product flashing
Cons:
- Multi-point flush injections are not recommended