Flowserve V-378 R1 Edward Equiwedge Gate Valve - Manual (Page 17)

17
Flow Control Division
Edward Valves
Disassembly Procedure of Bonnet Types Area 3
(cont.)
See illustrations No. 11 and 12.
1. With the valve in a partially open
position, loosen the gland nuts and
tap the gland to loosen engagement
of the gland barrel with the packing
chamber. This should relieve any
pressure that may be trapped in the
valve.
2. The handwheel nut is locked in
position with a small nylock set
screw. Loosen the set screw then
remove the handwheel nut. The
handwheel is keyed to the yoke
bushing so remove the handwheel
and key and set them aside.
3. Loosen and remove the yoke cap
screws or yoke lock ring bolts. If the
valve is equipped with a yoke lock
ring, it will be necessary to pry it
off by using a cold chisel, tapping it
into one of the splits to disengage
the clamp rings.
4. Sling the yoke through opposite
windows leaving space to turn the
yoke bushing and take up slack in
the chain hoist. With a strap
wrench around the top of the yoke
bushing, turn the valve to close.
When the gates contact the seats,
the yoke will rise. Continue turning
until the yoke bushing threads are
disengaged from the stem.Carefully
lift the yoke over the stem and set
aside on a plywood board or a
bed of rags.
5. Remove the gland bolts and gland.
Loosen and remove the bonnet
retainer nuts and lift off the bonnet
retainer. Set the parts aside.
6. Place an eyebolt in the threaded
end of the stem.With a chain hoist
mounted in line with the stem and
fastened to the eyebolt, pull the
stem firmly against the backseat.
With clean rags and a vacuum,
clean the top of the valve and
exposed surfaces of the bonnet and
gasket retainer segments.
7. Slack off the chain hoist and with a
brass bar and hammer, and drive
the bonnet down so that the gasket
retainer segments are fully exposed.
8. Using the same tools, drive the gas-
ket retainer segments down to the
bottom of the groove (about 1/16”
[2mm]) in the body.
9. Remove the gasket retainer seg-
ments and set them aside.
10. Place the bonnet retainer back on
the body and with a chain hoist
and lift the stem and bonnet so that
the bonnet contacts the gasket.
Screw nuts onto the bonnet studs
and tighten in a star pattern to jack
out the gasket. Be careful not to
cock the bonnet.
Note: The stem should not be used to
remove the pressure seal gasket.
11. When the bonnet assembly breaks
loose, use a chain hoist to lift the
assembly from the valve body, but
be careful to clamp the gate halves
securely before fully withdrawing
the parts (see illustration No. 17,
pg 25). This is necessary because
when the gate halves are disen-
gaged from the body guide
grooves, the gate halves and spac-
er ring can fall off the stem. Place
the assembly on a bed of rags.
Note: These instructions have been
sequenced for a valve in a horizontal
pipeline with the stem in the vertical, up
position. With a different stem orientation
the steps will have to be slightly modified.
For example, in step 6, if the valve was in
a horizontal pipeline with the stem down
when the gasket comes free, all the parts
would fall; some provision must be made
to support the stem-bonnet assembly when
the gasket breaks loose.
Type IV & V,
Sizes 4”-24,
Classes 900,
1500, 2500-
Figure numbers
1911,1911Y,
11511, 11511Y,
12511, 12511Y,
14311Y,
12011Y, or
14411Y
Valve Type V
Valve Type IV
Illustration No. 11 Illustration No. 12