API Plan 11 Flush
API Plan 11 recirculates flow from a high‐pressure section of the pump, typically the discharge piping, through a flow control orifice to the seal. Plan 11 is the default flush plan for most pumps.
- Removes heat from the seal chamber
- Ensures proper pressure in the seal chamber in order to prevent pumped fluid from vaporizing
- Allows seal chamber to be self-venting when used with horizontal pumps
See page 7 of the Mechanical Seal Support Systems Applications Guide for additional details.