API Plans

Plan 13

Description: Plan 13 is recirculation from the seal

chamber or gland through an 1/8” minimum flow

control orifice (when necessary), back to the pump

suction. Standard flush plan for vertical pumps.

Objective: Remove seal generated heat and vent

vertical pumps.

Advantages: Used in applications where the seal

chamber pressure is greater than suction pressure.

Can reduce the seal chamber pressure when used

along with a close‐clearance throat bushing.