Flowserve V-377 R4 Edward Valves - Manual (Page 38)

38
Flow Control Division
Edward Valves
Type III Pressure-Seal Bonnets –
Tilting Disk Check Valves
Sizes 6”and larger.
See Illustration No. 26 on page 38.
As explained under “Seat and Disk
Repairs” on page 14, this manual does not
include information for repair of the seat
and disk of Tilting Disk Check Valves.
Consult your Edward Sales Representative.
1. Remove the cover/cover retainer.
2. Screw an eyebolt into the tapped
hole in the cover.
3. Fasten a chain hoist to the eyebolt
and pull up just enough to eliminate
all slack in the hoist.
4. Remove all cover stud nuts or cap
screws.
5. Remove the cover retainer.
6. Mark the body, cover and gasket
retainer segments with adjacent prick
punch marks so that their relative posi-
tion can be restored on reassembly.
7. With clean rags and an air hose,
thoroughly clean the top of the valve
and all exposed surfaces of the cover
and gasket retainer segments. This is
important.
8. Slack off on the chain hoist to permit
the cover to slip down into the valve
body. If necessary, tap lightly to
loosen. If the cover resists any rea-
sonable attempts to force it into the
valve body, high-pressure fluid may
be trapped in the bonnet cavity (and
downstream) of the check valve. The
cover will drop easily when this pres-
sure is relieved. Lower the cover until
it rests on top of the disk.
9. With a copper or brass drive pin or
a clean hardwood block, drive the
gasket retainer segments downward
to the bottom of the retainer groove
(about 1/16”) in the body.
10. Remove the gasket retainer segments.
11. Lift the cover back into contact with
the pressure-seal gasket, again using
the chain hoist.
12. Replace the cover retainer, using
shims to provide additional clearance
for further upward movement of the
cover.
13. Use three or four nuts or screws in a
uniform spacing on the bonnet studs
to pull the cover and gasket out of the
body. All nuts or screws should be
turned uniformly, a fraction of a turn
at a time, using a star pattern. It is
possible to damage valve parts by
cocking the cover, so uniform turning
of the nuts is very important.
Disassembly Procedures for Bonnet Types
(continued)
Illustration No. 26
Type III Bonnet on Tilting Disk Check Valve
LIFT HAND WOUND SPRING COLORED GREEN
AND ASSEMBLED ON THIS SIDE