Armstrong GD-10 User manual

Bulletin No. AY-741-A
Typical Piping For Air
Model GD-10, GD-10N and GD-10F
Pressure Reducing Valve
Installation and Maintenance Instructions
Armstrong GD-10, 10F, 10N
Pressure Reducing Valve
By-Pass
Strainer
Liquid
D
rainer
Start-Up and Adjusting Procedures
Improperadjustmentofthepressurereducingvalvemaycausehunting,scaleproblems,etc.,anddamagetothevalve
itself. Adjust the valve as follows:
Typical Piping For Steam
Globe
Valve
TVS Trap
Safety Reli
ef
Valve
By-Pass
GD-6
Minimum of 10 inlet
Pipe Diameters from
PRV to First Turn
Minimum of 20 outlet
Pipe Diameters from
PRV to First Turn
Note: Safety ReliefValve to be set at
10 psi higher or 90% higher than
the downstream pressure, whichever
is greater.
Minimum of 10 outlet
Pipe Diameters from
Last Valve or Fitting
Strainer
1. Closethegatevalvesbeforeandafterthepressure
reducingvalve. Opentheglobevalveinthebypassline
and blow down the inlet piping. Adjust the opening of
thebypass valveso thatthe safetyvalveif useddoes
not blow. After blowing the system down, close the
bypassvalve.
2. Loosen the lock nut and adjusting screw to relieve the
adjustingspring.
3. Slowly open the inlet side gate valve to the fully open
position,andpartially open theoutlet valve soonly a
small amount of fluid can pass.
This bulletin should be used by experienced personnel as a guide to the installation of the Model GD-10, GD-10N and
GD-10FPressure Reducing Valve. Selectionor installationof equipmentshould always beaccompanied bycompetent
technical assistance. You are encouraged to contactArmstrong International, Inc. or its local representative for
additionalinformation.

Armstrong-Yoshitake, Inc., 221 Armstrong Blvd., P.O. Box 408, Three Rivers, Michigan 49093 - USA Ph: [phone] Fax: [phone]
www.armstrong-intl.com
Bulletin No. AY-741-A 1/01 Printed in U.S.A.
Problem Cause Solution
The inlet pressure is not suitable. Change the pressure to the
appropriate level.
The valve size is excessively smaller that what is required Change to the appropriate size.
The inlet strainer is clogged by a foreign substance Disassemble and clean the straine
r
The pressure gauge is out of order. Replace the gauge
The valve and the valve seat are clogged by a foreign
substance Disassemble and clean the valve seat
The "O" ring is damaged Replace the "O" Ring
The desired pressure
cannot be obtained
The outlet pressure rises
higher than the specified
pressure.
Troubleshooting Guide and Disassembly Instructions
DisassemblyofBody
Turnthevalveguidecounterclockwiseand
remove it from the body. Pull out and
removethevalveandspring.
DisassemblyofDiaphragm
1. Slightly loosen the lock nut (16) and turn
thehandlecounterclockwisetounload
theadjustingspring(17).
2. Removethelocknut(16)andremovethe
bonnet (?) from the body(1). Pull out and
removethetopspringplate(6),adjusting
screw(15),anddiaphragm(19).
NotesToReassemble
1. Check to be sure the disc (9) and the seat
(12)arenotflawed.
2. Apply grease to the "O" ring (27).
3. Attachthe diaphragm(19) to thespecified
location without twisting.
Bolt (22)
Valve Seat
(12)
Bottom Cap
(2)
Gasket (23)
Gasket (25)
Diaphragm (19)
Nameplate
Locknut (16)
Adjusting Screw (15)
Spring Housing (3)
Rivet (29)
Top Spring Plate (6)
Adjusting Spring (17)
Nut (21)
Spring Washer (20)
Bottom Spring Plate (5)
Diaphragm Stopper (14)
Gasket (24)
Spring (18)
Nut (11)
Flat Washer
(10)
Valve (7)
Disc (9)
Spindle (8)
Body (1)
Guide Pipe
(26)
Guide (13)
O-Ring (27)
4. Slowly turn the adjusting screw clockwise until the
desiredpressureisobtainedonthedownstream
pressuregauge.
5. Slowlyopen theoutlet valve tothe fully openposition.
6. After adjustment, fasten the lock nut.