Instructions EM39003 - 05/10
39003 Series High Performance butterfly Valves
12
12
9.
With the disc in the closed position place the seat retainer
with seat into the counterbore of the body.
A. Cap Screw Retainer:
Apply lubricant to the cap screw threads and tighten
them down uniformly.
B. Wedge Ring Retainer:
Place the wedge ring in the groove on the outside
edge of the retainer taking care to position the wedge
ring gap away from any set screw. Using opposing
C-clamps, pull the retainer into a position flush with
body face. (The C-clamps should not block access to
the set screw holes.)
10.
Open the disc and relax the retainer pressure slightly to
permit the seat to expand fully inward against the seat
retaining lip machined in the retainer and body seat
cavities. A positive “snap” action will be observed.
A. Cap Screw Retainer:
Leaving the valve disc open, retighten the cap screws
to the torques specified in Table 3.
B. Wedge Ring Retainer:
Leaving the valve disc open, retighten the C-clamps
and install the set screws. Remove the C-clamps after
all screws have been tightened.
11.
Operate the disc several times and inspect the seat for
damage before reinstalling the valve in the pipeline.
12.
Inspect the position of the disc in the closed position
to determine whether the actuator stops are adjusted
properly. The face of the disc should be parallel to the seat
retainer face when the valve is in the fully closed position.
Table 3
Valve Size (in.)
Torque (in.-lb.)
2 to 12
50
14 to 20
75
24 to 48
100
3.6 Fire-Safe and Metal Seat Replacement
1.
Follow Steps 1 and 2 of Soft Seat Replacement instructions.
2.
Remove old soft seat and graphite gaskets and discard.
Clean and inspect the metal seat.
3.
If metal seat is scored, bent or otherwise damaged it will
require replacement.
4.
Thoroughly clean the seat cavity in the body and the seat
retainer prior to installing the new seat.
5.
Carefully clean and polish the disc edge sealing surface
with a soft cloth. The disc sealing surface should be free of
all grooves and scratches.
6.
A graphite gasket is required on both sides of the metal
seat. gaskets can be made from self-adhesive graphite
tape as follows:
A.
Suggested graphite tape size:
2" – 12" valves – 1/2" wide
14" – 48" valves – 1" wide
B.
To install the tape, peel off 6" of backing paper at a
time. Apply the tape to the metal seat covering the flat
outer edge area on both sides. Overlap the two ends
of the tape a minimum of 1/8 inch.
Note: It is important that both sides have gaskets.
C.
Smooth tape as much as possible by hand. Slight
roughness is acceptable and will be pressed flat
during final assembly. Avoid tearing tape. If a tear
occurs, tape should be overlapped a minimum of 1/8
inch. Trim excess tape from outside diameter of the
seat.
D.
If cap screw retainer design, bolt holes in metal seat
should be opened by slitting an “X” in the hole. Do not
attempt to cut round holes.
7.
For Fire-Safe valves, place the preformed seat assembly
in the body seat cavity with the marked (tape) side up. For
metal seated valves, place the 316SS back-up ring in the
body seat cavity.
8.
Place the metal seat with the graphite gaskets on the TFE
Figure 11
