Leslie Controls GP Pressure reducing valve - Manual (Page 5)

Page 5
SECTION III — MAINTENANCE
Leslie control valves may be dismantled without removal from
pipeline when maintenance checks are desired.
Play Safe! Use Only Genuine
Leslie Replacement Parts
All Leslie control valves are made of high quality materials,
are time-tested and backed by more than a half century of
knowhow. Machining is done by expert craftsmen and each
valve is inspected and service-tested before shipment to
you.
Use of other than GENUINE LESLIE PARTS may impair their
ability to work properly. DO NOT change any dimensions
except as noted in these instructions. To assure long life,
preservation of parts interchangeability and low maintenance
costs, use only standard LESLIE PARTS.
CHECK NAMEPLATE FOR PROPER CLASS AND WRITE
FOR APPLICABLE DRAWINGS.
Dismantling
1. Shut off air supply. Disconnect loading line to release
air pressure from diaphragm area.
2. Close stop valves on inlet and outlet sides of control
valve and open strainer blowdown valve to vent
trapped fluid.
3. Loosen and remove bottom cap. Gasket, main valve
spring and main valve will follow.
4. Do not remove seat ring unless remachining or replace-
ment is necessary. If removal is necessary, see Figure
6 with accompanying instructions.
5. To examine diaphragm (two leaves) and main valve
guide or to clean diaphragm area, remove diaphragm
cover bolts/nuts, diaphragm and diaphragm disc. To
take out diaphragm disc, form two hooks of 1/16”
diameter wire and lift out disc.
Cleaning, Replacing or Repairing Parts
Clean all parts with kerosene or other approved solvent and
check as follows:
1. Examine main valve, seat ring and main valve guide.
Remove any encrusted material with crocus cloth.
2. FOR ALL-METAL SEATS ONLY: If main valve or seat
ring seating surfaces are cut or scored, regrind with
600 grit grinding compound. Remove all trace of
grinding compound before reassembling.
NOTE: If main valve, seat rings or both must be remachined
due to damage to seating surfaces, in order to maintain cor-
rect diaphragm disc to diaphragm seat dimension, it will be
necessary to shorten the main valve. To do this, remove
from the top of the main valve stem (diaphragm disc end) an
amount of metal equal to the amount (dimensional thickness)
removed from the main valve and or the seat ring.
Use 600 grit compound, lap the main valve into the seat.
When relapping main valves in sizes 2-1/2” larger, take off
diaphragm cover and remove diaphragms so that their spring
action will not interfere with the lapping operations.
Replacing Seat Rings
To remove seat rings, use the special wrench which is avail-
able on request. See Figure 6.
Position seat ring wrench and socket wrench as shown in
Figure 6. Hold tightly against seat ring. Tap handle of sock-
et with hammer to loosen seat ring. Then unscrew seat ring.
Figure 4 — GP Type Control Valve
Figure 5 — Soft Seat Ring
Figure 6 — Removing Seat Ring
Seat Ring Wrench -
Insert Bar Through Hole
Seat Ring
Diaphragm
Cover
Seat Ring
Diaphragm
(2 leaves)
Diaphragm
Disc
Main Valve
Guide
Main Valve
Main Valve
Spring
Gasket
Bottom Cap