Norriseal Series 2700A Operating And Maintenance Manual Download Page 3

Page: 3 / 16

P.O. Box 40525, Houston, Texas USA 77240-0525

Tel: 713·466·3552 · Fax: 713·896·7386

www.norriseal.com

PERATING AND

AINTENANCE

ANUAL

Series 2700A Control Valve

only Norriseal replacement parts.

Please refer to the serial and model

numbers on the nameplate when

ordering replacement parts.

Maximum allowable pressures for the
valve body and actuator and the maxi-
mum allowable temperature for the
valve are shown on the nameplate. If
pressure to the valve is capable of ex-
ceeding these limits, install relief valves
and other protection devices.

When ordered, the valve configura-
tion and construction materials were
selected to meet the specific pres-
sure, temperature, pressure drop and
fluid conditions. Since some body/trim
materials are limited in their pressure
drop and temperature ranges, do not
apply any other conditions to the valve
without first contacting your Norriseal
sales representative.

You will see warning boxes like this
throughout the manual. Please read
and strictly observe these warnings to
prevent personal injury or equipment
damage. Before you begin the instal-
lation, operation or repair of equip-
ment, make sure to completely review
and understand the instructions in this
manual.

Scope

This instruction manual includes

installation, operation and mainte-

nance information for Norriseal Se-

ries 2700A Control Valves. Please

refer to separate manuals for instruc-

tions covering controllers and posi-

tioners.

Description

The Series 2700A Valve is designed

for general purpose use applica-

tions for modulating or on/off service

in liquid or gas control. The Series

2700A has a single-port body with

two types of trim—plug control and

cage control. Plug control can either

be balanced or unbalanced. Cage

control must always be balanced.

The Spring/Diaphragm Actuator has

a spring under the diaphragm for

both direct (fail open) and reverse

(fail closed) settings.
The plug control trim, which can ei-

ther be balanced or unbalanced, is

used when fluid is flowing up under

the valve plug. The fluid pressure

drop will occur between the plug and

the seat. The curve on the plug will

signify the flow as quick opening or

modified percent.
The cage control trim, which must

always be balanced, can be used

when fluid is moving either up or

down. The fluid pressure drop will

occur at the cage’s port. The curve

on the cage will signify the flow as

linear or equal percent.

Norriseal valves come standard with

spring diaphragm pneumatic actua-

tors. These actuators are available

in spring closing or spring opening

types and are both available in a

range of sizes to suit your operating

conditions.
Series 2700A valves are available

with either adjustable or non-ad-

justable packing. Non-adjustable

packing is Chevron V-ring style with

a spring below the packing to main-

tain a positive stem seal. Adjust-

able packing is square compres-

sion packing, either Teflon/Kevlar or

Grafoil material. Both packing types

are held together with two studs that

hold a compressor bar to the pack-

ing retainer. The Series 2700A bon-

nets have a NPT thread, if you wish

to add an optional packing lubricator.

Before disassembly or maintenance,
all pressures in this device must be re-
lieved. Failure to relieve pressures may
result in personal injury or device dam-
age. The resulting uncontrolled vent-
ing or spilling of line fluids may cause
personal injury, loss of process control
or environmental contamination.

Valve Identification

The nameplate of the valve is at-

tached to the upper diaphragm

housing of each valve. The name-

plate lists the serial number, series

number and model number, as well

as other information applicable to

the particular valve assembly, includ-

ing trim size, trim and plug materials

and pressure and temperature limits.
Valve model numbers are 13

characters long (an example of a

model number would be: RF-14TGS-