FLOWSEAL
3201 Walnut Avenue, Long Beach, CA 90807
562/426-2531
FAX 562/490-9546
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MAINTENANCE INSTRUCTIONS
11
Standard Soft Seat Replacement (cont.)
Carefully clean and polish the disc sealing surface with a
soft cloth. The disc sealing surface should be free of all
grooves and scratches.
Place the seat retainer on a flat surface with the seat
locating area facing up.
Place the new preformed seat assembly (Seat and O-
ring) on the seat retainer with the marked (tape) side
facing down.
Using the balls of each thumb, press down on the seat
engaging the shoulder of the seat behind the lip in the seat
retainer. Stretch the seat into place by sliding each thumb
around the circumference of the seat maintaining down-
ward pressure and forcing the seat shoulder over the seat
retainer lip.
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:
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:
Operate the disc several times and inspect the seat for
damage before reinstalling the valve in the pipeline.
Table 3
2 to 12 50
14 to 20 75
24 to 48 100
Valve Size (in.) Torque (in-lb)
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 posi-
tion flush with body face. (The C-clamps should
not block access to the set screw holes.)
Inspect the position of the disc in the closed position to
determine whether the actuator stops are adjusted prop-
erly. The face of the disc should be parallel to the seat
retainer face when the valve is in the fully closed position.
Leaving the valve disc open, retighten the C-
clamps and install the set screws. Remove the C-
clamps after all screws have been tightened.
