GD-200 and 200H Pressure Reducing Valve

GD-200 and 200H Pressure Reducing Valve
Bulletin No. AY-275-A
Model GD-200, 200H, 200S
Pressure Reducing Valve
Installation and Maintenance Instructions
Typical Piping For Gas and Liquid (Water)
Globe
Valve
Minimum of 10 Outlet
Pipe Diameters from
Last Valve or Fitting
By-Pass
Safety Relief
Valve
Armstrong
Strainer
GD-200
Minimum of 10 Inlet
Pipe Diameters from
PRV to First Turn
Minimum of 20 Outlet
Pipe Diameters from
PRV to First Turn
Note:
Safety Relief Valve to be
set at 10 psi higher or 10%
higher than the downstream
pressure, whichever is
greater.
This bulletin should be used by experienced personnel as a guide to the installation of Models GD-200, 200H, and 200S
Pressure Reducing Valves. Selection or installation of equipment should always be accompanied by competent
technical assistance. You are encouraged to contact Armstrong International, Inc. or its local representative for
additional information.
Installation Instructions
1. For air service a liquid drainer should be used to keep
air as dry as possible before the valve.
2. An Armstrong Y-Strainer (100 mesh recommended)
should be installed before the PRV to reduce the
chance of dirt fouling.
3. Pressure gauges should be installed before and after
the PRV.
4. Piping a bypass line with a globe valve around the
PRV will allow system operation while the PRV is
being serviced.
5. Do not install quick opening or closing valves
downstream of PRV.
6. Install the PRV with the flow in the direction of the
arrow on the body.
Startup and Adjustment Procedures
Follow the steps below, and slowly turn the adjusting screw to the desired set pressure. Incorrect adjustment may
cause hunting, water hammer, etc., resulting in damage to the valve and other equipment:
1. Close the isolation valve at inlet and outlet side of the
pressure reducing valve, and take sufficient time not to
blow the safety valve, blow off the fluid to remove
foreign matter via the by-pass line. After blowing it
down close the by-pass line isolation valve.
2. Slowly open the isolation valve at the inlet side of the
pressure reducing valve, and adjust the travel of the
isolation valve at the outlet side of the pressure
reducing valve so that a little fluid flows.
3. Loosen the lock nut, and slowly turn the adjusting
screw (clockwise to increase, counterclockwise to
reduce) while observing the pressure gauge on the
outlet side.
4. Slowly open the isolation valve at the outlet of the
pressure reducing valve, and readjust the desired
pressure.
5. After adjustment, tighten the lock nut.
Troubleshooting Guide
Problem
Pressure
does not
reach the
desired
value.
Reduced
pressure
raises above
the adjusted
valve
pressure.
Abnormal
noise is
heard.
Other
Solution
Causes
1. Incorrect pressure is being used.
2. The connecting pipe is plugged with foreign
matter.
3. Nominal size is too small for the
specifications.
4. Pressure is not adjusted correctly.
5. Strainer installed before pressure reducing
valve is plugged.
6. Pressure gauge is broken.
1. Foreign matter exists between main valve and
main valve seat, or scratches exist.
1. Correct the pressure.
2. Disassemble and clean the connecting pipe.
3. Change the nominal size appropriately.
4. Observe the adjustment procedures and
readjust pressure.
5. Disassemble and clean strainer screen.
6. Replace gauge.
2. The o-rings are damaged.
3. By-pass valve is leaking.
1. Disassemble and remove the foreign matter.
When any scratches are identified, lap the
main valve and main valve seat.
2. Replace the o-rings.
3. Repair or replace by-pass valve.
1. Valve size is too large for the application.
1. Change to the appropriate size for application.
2. Pressure reducing ratio is too large.
3. Air in liquid.
4. An abrupt OPEN/CLOSE valve is located too
close to the pressure reducing valve.
2. Reduce pressure in two stages.
3. Air eliminator or vent.
4. Allow as much space as possible between
the valves.
1. Springs and diaphragm are worn.
1. Replace the springs and diaphragm.
Important Notes:
• Foreign matter and scale in a pipe may cause most pressure reducing valve problems on start up. Make sure all
foreign matter is removed from the piping.
• Valve trouble may happen due to a faulty pressure gauge, fluid leakage from a by-pass valve, failure to close the
by-pass valve, a plugged strainer, etc.
Disassembly
Note: Be sure that all internal pressure has been discharged before disassembling and inspecting the valve. In case of
a high temperature application, be sure to cool the valve before disassembling and inspecting. *Failure to do so may
result in injury or burns due to residual pressure or spillage around the valve. (Refer to Figures 1-1 & 1-2).
5. To remove the retainer, loosen and remove the retainer
guide clamping bolt and pull the retainer guide.
6. To remove the valve seat, pull the spindle up.
1. Relieve the pipe pressure completely, and make sure
there is zero pressure.
2. Slightly loosen the lock nut and turn the adjusting
screw counterclockwise to relieve the adjusting spring
(Unload the spring).
3. Remove the hexagon bolts from the spring chamber,
remove the spring chamber, and take out the adjusting
spring and spring plate.
4. To remove the diaphragm “hold” the spindle and
remove the hexagon nut.
Note: To remove the retainer guide easily, screw the
retainer guide clamping bolt to retainer guide and pull it
apart. Install the spring plate and the hexagon nut to
spindle again and pull the spring plate.
Reassembly
1. Make sure that the diaphragm, the valve seat and the
valve have no flaws.
2. After confirming there are no flaws on the o-ring, apply
silicone grease to the o-ring.
3. Install the spring chamber after confirming whether the
border of the diaphragm is properly fitted in the groove
of the body.
4. There is a gap between retainer guide and body and it
shows these parts positioned correctly. Tighten the
bolts evenly and be sure not to tighten too hard.
2
Figure 1-1
Exploded View Of
GD-200 (1/2 - 2”)
Adjusting Screw (15)
Lock Nut (16)
Bolt (29)
Nameplate (30)
Rivet (32)
Spring
Chamber (2)
Spindle (6)
Top Spring
Plate (13)
Valve Seat (8)
Spring (14)
O-Ring (22)
U-Nut (19)
Washer Disc (10)
Valve (9)
Lock Washer (18)
O-Ring (23)
Bottom Spring
Plate (12)
Diaphragm (11)
Valve Cover (7)
Conductor
Pipe (25)
U-Nut (19)
Air Vent (26)
Retainer (4)
O-Ring (27)
O-Ring (20)
Bolt (28)
Retainer
Guide (5)
Joint A (29)
Pipe (28)
O-Ring (21)
Joint B (29)
O-Ring (24)
Air Vent (26)
O-Ring (27)
Body (1)
Cap (3)
Conductor Pipe (28)
2-1/2" - 6"
Needle Valve (41)
3
Figure 1-2
Exploded View Of
GD-200 (2-1/2 - 4”)
Adjusting Screw (15)
Lock Nut (16)
Bolt (29)
Nameplate (30)
Rivet (32)
Spring
Chamber (2)
Spindle (6)
Top Spring
Plate (13)
Valve Seat (8)
O-Ring (22)
Spring (14)
U-Nut (19)
Washer Disc (10)
Valve (9)
Lock Washer (18)
O-Ring (23)
Bottom Spring
Plate (12)
Conductor
Pipe (25)
Diaphragm (11)
Valve Cover (7)
U-Nut (19)
Air Vent (26)
Retainer (4)
O-Ring (20)
O-Ring (27)
Bolt (28)
Joint A (29)
Retainer
Guide (5)
O-Ring (21)
Pipe (28)
Spindle
Guide (26)
Cover
Gasket (27)
Air Vent (26)
O-Ring (27)
Body (1)
Bulletin No. AY-275-A 11/01
Joint B (29)
Conductor Pipe (28)
2-1/2" - 6"
Cover (3)
Bolt (35)
Needle Valve (41)
Armstrong-Yoshitake, Inc.
221 Armstrong Blvd., P.O. Box 408, Three Rivers, Michigan 49093 - USA Ph: (269) 279-3600 Fax: (269) 273-8656
Steam Traps \ Humidifiers \ Steam Coils \ Valves \ Air Vents \ Pumping Traps \ Water Heaters
Printed in U.S.A.
www.armstrong-intl.com
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement