Val-Matic 3-24 Butterfly Valve With LSA Actuator and External Stops - Manual (Page 11)

11
REASSEMBLY
All parts must be cleaned and gasket surfaces
should be cleaned with a stiff wire brush in the
direction of the serrations or machine marks. Worn
parts, gaskets and seals should be replaced during
reassembly. Bolts should be lubricated and torqued
per Table 6 during reassembly.
TABLE 6. LUBRICATED BOLT TORQUES
1. Insert new bearings (5) into both ends of the
valve body (1) and insert the shaft (4) through
the body and disc (3).
2. Install taper pins (9) with washers (12) and nuts
(11).
3. Install new seat (6), retaining ring (7) and seat
bolts (8) into disc. Apply thin film of FDA
silicone grease such as Dow Corning #7 to
rubber surface. Lightly tighten seat bolts until
bolt heads touch ring.
4. Lubricate ID and OD of packing set with FDA
grease and install in packing bore one ring at a
time taking care to keep lips pointing down
toward valve.
5. Center disc in body and install bottom thrust
bearing (18) and cap (15). Secure with cap
screws (16).
6. Torque cap screw to torque given in Table 6.
7.
Insert key (14) into shaft and place actuator over
valve. Reinstall actuator mounting bolts and
torque per Table 6. Install cover on actuator.
Cycle valve. Apply pressure to valve and check
for seat leakage. Tighten seat bolts ½ turn at a
time as necessary.
8. If valve does not shut off tight, adjust the closed
position stops as described on page 6 under
"Closed Position Adjustment".
SEAT REPLACEMENT
If the seat is badly worn or damaged, gain access to
valve interior and remove existing cap screws, seat
retaining ring, and seat.
1. Clean mating surfaces of body seat, disc, and
retaining ring with stiff wire brush in the direction
of the machine grooves.
2. Install new seat (6) onto disc so that the o-ring
bead side is against the disc with the holes
aligned.
3. Start at the top of the disc and install a section of
retaining ring (7) with three new seat hex head
cap screws (8) and lightly tighten seat bolts until
the bolt heads touch the retaining ring.
4. Apply a thin film of FDA silicone grease such as
Dow Corning #7 to the exposed rubber surface
and close the valve so that the disc is level with
the flange face within +/- 1/8 in.
5. Tighten the seat hex head cap screw in a cross-
over pattern in two steps to the torque given in
Table 3 using a socket wrench.
6. Cycle valve open and closed and verify that disc
closes within +/- 1/8 in of center. Conduct a
pressure test. If necessary, tighten seat hex
head cap screw ½ turn to stop any leakage.
FIGURE 12. SEAT REPLACEMENT
SIZE TORQUE (FT-LBS)
3/8"-16
20 - 30
7/16"-14 30 - 50
1/2"-13 45 - 75
5/8"-11 100 - 150
3/4"-10 150 - 250
7/8"-9 200 - 350
1"-8 300 - 500
1 1/8"-7 450 - 700
1 1/4"-7 650 - 1000