API Plans

Plan 54 & Plan 55

Description: Plan 54 is an external system supplying clean

BARRIER fluid to an Arrangement 3 dual seal at greater pressure

than the process pressure being sealed. Pressure and circulation

are provided for by an external pump or pressure system.

Objective: Same as Plan 53A and will provide constant pressure

and flow through circulation system.

Advantages: Same as Plan 53A but provides excellent circulation

and cooling. Can be used on multiple seals to reduce cost. The

barrier fluid enters the seal and exits in a once in and once out


Plan 55 is similar to Plan 54 except the

system is supplying clean BUFFER fluid at

less pressure than the process pressure

being sealed, to an Arrangement 2 dual

seal. No process contamination and

improved cooling over Plan 52.