Flowserve CPM Supply Tank User Manual

Flow Solutions Division

CPM Seal Support
Reservoir Assembly

Installation Instructions

Introduction

This manual covers the installation and operation of the CPM Seal
Support Reservoir for dual non-pressurized (API Plan 52/ANSI Plan

7352) and dual pressurized seals (API Plan 53/ANSI Plan 7353). The
following instructions describe the appropriate system, buffer/barrier
fluids, installation, start-up, and maintenance.

Reservoir

The standard CPM Seal Support Reservoir is designed in accordance
with ASME Code Section VIII, Division 1. All tanks are welded in accor­dance with ASME Code Section IX. Tanks include inlet, outlet, vent and
fill along with two mounting lugs as minimum connections.

Sealing System Description

CPM Seal Support Reservoir can be used as reservoirs for dual pressur­ized Inside, dual pressurized inside/outside or dual non-pressurized
Flowserve Seal designs. The sealing system produced is defined as
being either a thermal convection system or a forced circulation system.

Support System Descriptions

An API Plan 53/ANSI 7353 is a pressurized dual seal system which is
used in services where no process leakage to atmosphere is tolerated.
The system consists of dual mechanical seals with a barrier fluid be­tween them. The barrier fluid in the supply tank is pressurized to a higher
pressure (normally 25 psig [1.7 bar]) than the seal chamber maximum
160 psig [11 bar]). Primary (inboard) seal leakage will be barrier fluid into
the product. Minimal leakage is customary.

An API Plan 53/ANSI Plan 7353 is usually chosen over an API Plan 52/
ASNI Plan 7352 for dirty, abrasive, or polymerizing products which would
either damage the seal faces or cause problems with the barrier fluid
system if an API Plan 52/ANSI Plan 7352 is used. Two conditions to
consider when incorporating API Plan 52/ANSI Plan 7352; first, there will
always be some leakage of barrier fluid into the product. Normally, this
leakage will be minute, and the leakage rate can be monitored via the

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visual water flow indicator. However, when using API Plan 53/ANSI Plan
7353 the product must be able to accommodate a small amount of
contamination from the barrier fluid. Secondly, an API Plan 53/ANSI Plan
7353 system is dependent on having the supply tank pressure main­tained at the proper level. If the supply tank pressure drops below seal
chamber pressure, seal leakage direction will be reversed and the barrier
fluid will be contaminated with the process fluid. The flush plan will then
become an API Plan 52/ANSI Plan 7352.

An Induced Circulation System is essentially the same as the thermal
convection system except for the addition of a circulating device in the
seal cavity which provides for positive flow in the system. The addition of
a circulating device provides for positive flow of buffer fluid shown in
Figure 1. To maximize dual seal cooling add cooling coils inside the
reservoir as a means of removing heat.

Dual Pressuzied Inside Seal with Induced Circulation
through CPM Seal Support Reservoir with Cooling Coil

Figure 1

Plan 53/ANSI Plan 7353

vertical
porting

outlet

end view

inlet

seal

tangential

or

porting

seal

end view

outlet

inlet

vent valve

pressure

gage

level
gage

cooling out

visual water
flow indicator

water
pressure
regulator
and inlet
port

304SS,
2 gallon
reservoir

cooling in

drain

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