API Plans

Plan 23

Description: Plan 23 is recirculation of process fluid

from the seal chamber, through a seal flush cooler,

back into the seal chamber utilizing a pumping ring.

Objective: Cool process, improving lubricity and

increasing the vapor margin in the seal chamber.

Reduce coking.

Advantages: Has greater

cooling efficiency than

Plan 21 because it

continuously recirculates

the seal chamber fluid

through the seal flush

cooler. It decreases

cooler duty, reduces

cooler fouling and

increases cooler life.

Recommendation: Vent tubing before

pump start‐up and use close‐clearance

throat bushing in seal chamber.