Flowserve V-377 R4 Edward Valves - Manual (Page 40)

40
Flow Control Division
Edward Valves
3. Remove the bonnet retainer ring cap
screws. Due to space limitations, a
special tool may have to be used.
Make it from a standard Allen socket
wrench.
4. Open the valve fully so the stem is
back-seated on the bonnet and im-
pact with the handwheel several
times to break the pressure-seal gas-
ket loose from the body. Once the
gasket is free, discontinue turning the
handwheel.
5. Remove the yoke lock ring studs and
nuts.
6. Remove the yoke lock ring using a
small pry bar to separate the halves.
7. To make certain the pressure-seal gas-
ket is free in the body, attach a chain
hoist to the handwheel and lift the
yoke and bonnet assembly up a max-
imum of 1/4”. Do this with a hoist of
at least 1000 lb. capacity. If the stem
of the valve is not mounted vertically,
position the hoist slightly away from
the handwheel in line with the stem.
8. Lower the hoist and valve assembly
back to a slack position.
9. Loosen the stem guide collar lock nut,
back off the stem guide collar lock
screw and remove the stem guide
collar key.
10. Turn the crossarm in a direction to
close the valve thus unscrewing the
yoke from the stem. The stem must be
restrained from turning; a flat tool
held in the stem guide collar key slot
is convenient, being careful not
damage the slot.
11. The hoist may have to be used for
step 10, if the stem is not vertical, to
allow the parts to turn freely.
12. Lift the yoke assembly clear of the stem
and body assembly, simultaneously
slipping the stem guide collar off of the
stem.
13. Mark the bonnet, bonnet retainer ring
and body with adjacent prick punch
marks so that their relative position
can be duplicated in reassembly.
14. Remove the gland bolt nuts and
gland.
15. Remove the bonnet retainer ring.
16. With clean rags and air hose, thor-
oughly clean the top of the valve and
all exposed surfaces of the bonnet
and pressure-seal gasket. This is
important.
17. Mark the pressure-seal gasket at a
point (other than seal surfaces) corre-
sponding to the previous mark on the
body (see step 13).
18. Screw an eyebolt in the threaded end
of the stem.
19. For Stop Valves:
a. With the chain hoist mounted in
line with the stem and fastened to
the eyebolt, pull the stem, bonnet
and pressure-seal gasket out of the
valve so the disk nut contacts the
gasket retainer segments. Back off
1/8”.
b. Slide the bonnet, spacer ring (if
used) and pressure-seal gasket up
to the top of the stem and fasten in
place by wrapping the stem with
electrical tape, or other suitable
means.
20. For Stop-Check (non-return) Valves:
With the chain hoist mounted in line
with the stem and fastened to the eye-
bolt, pull the stem, bonnet, spacer ring
(if used), and pressure-seal gasket com-
pletely out of the valve. In laying the
parts aside for inspection, it is impera-
tive that they be placed carefully on a
bed of rags or other soft material to
avoid marring any machined surface,
particularly any seating and sealing
surfaces.
21. With a copper or brass drift pin, or a
clean hardwood block, tap the gas-
ket retainer segments to free them in
the body retainer groove. (Note that
they cannot be driven downward in
Type IV construction.)
22. Remove the gasket retainer segments
using two pieces of approximately
3/32 diameter wire bent 90°, half
an inch from the end. Insert the bent
end into the 1/8” holes provided for
this, removing each segment one at a
time.
23. For stop valves, remove the stem and
disk assembly from the valve, and lay it
down carefully as explained in step 20.
24. For stop-check (non-return) valves, the
piston-disk assembly is not attached
to the stem and must be removed sep-
arately. Reach down into the body
Disassembly Procedures for Bonnet Types
(continued)