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Instruction Manual
Form 5206
April 2004
seals until the minimum clearance is 0.38 mm (0.015
inches) for valves used for forward flow and 0.76
mm (0.030 inches) for reverse flow.
6. Once minimum clearance is obtained, temporarily
remove the flow ring.
7. Insert the O-ring (key 13) into the valve, and
secure the flow ring to the valve with the cap screws
(key 15).
Installing Live-Loaded PTFE Packing
These steps refer only to the Live Loaded PTFE
Packing. Key number locations are shown in
figures11, 12 and 13.
The valve shaft's packing surfaces are
critical in obtaining a good seal. If the
valve shafts are scratched, nicked or
worn, replace or repair the valve shaft
before installing the Live Loaded PTFE
Packing parts.
Both seal rings, drive end and follower
end, should be replaced at the same
time.
1. Remove the hex nuts (key 8) from the seal carrier
(key 17 on the drive shaft end and key 3 on the
follower shaft end). Remove the spacer (key 22).
On 4-, 12- and 24-inch sizes, the stud bolt (key 4)
will need to be removed. The drive pin (key 28)
needs to be removed from the outboard end of the
valve body.
2. Replace the seal carrier and spacer with the new
packing box (key 17 or 3). To keep the ball properly
centered inside the valve body, the bushing spacer
shims may need to be added or removed (see the
Installation of Single or Dual Ball Seal section).
3. Secure the packing box with hex nuts (key 8), for
6-,8-, 10-, 16, or 20-inch sizes, or socket head cap
screw (key 4), for 4-, 12-, or 24-inch sizes. Lubricate
the hex nuts or cap screws and tighten them. Be
careful not to damage the O-ring during installation
of the packing box.
4. Install the packing box studs (key 100).
The Belleville springs must be stacked
properly and packing box parts must
be assembled in the correct order, if
Note
Note
the packing parts are to function
properly.
5. Install the packing ring, female and male
adaptors, anti-extrusion rings, and packing box rings
(keys 105, 106 and 107). Be sure to install the
packing rings in the order and quantity shown in
figure 13.
6. Install the spring pack assembly (key 103 or 104),
which includes the Belleville springs, packing
follower, and O–ring. The O-ring is a non-functional
part used to retain the packing springs during
assembly.
7. Install the packing flange (key 102) on the shaft.
Then lubricate and install the packing nuts (key 101),
hand tightening them. Apply lubricant to the stud
threads, internal nut threads and contacting face of
the nut. Packing flanges with flats on the sides may
need to be oriented with the mounting bracket so the
flange will fit between the legs of the bracket.
8. To obtain optimum maximum benefit from the
packing system, tighten the packing flange nuts and
compress the Belleville springs to their Target Load.
The Belleville springs are designed to provide
optimum performance at their Target Load, 85% of
their maximum deflection/compression.
To obtain the Target Load compression, tighten the
packing flange nuts alternately and evenly, keeping
the packing flange parallel with the valve flange, until
the Belleville springs are compressed 100%. Then
loosen each packing flange nut one half turn (180_
of rotation).
Replacing Drive Shaft, Follower Shaft,
Ball, Bushings, and Valve Outlet
Gasket
This procedure is to be performed to replace the
valve ball, the drive shaft, and the follower shaft, if
the ball does not rotate in response to rotation of the
actuator end of the drive shaft, or if there is leakage
around the outlet gasket.
Disassembly
CAUTION
When removing the actuator from the
valve, do not use a hammer or similar
tool to drive the lever off the valve
shaft. Driving the actuator lever off the
valve shaft could move the ball (key 2)
V250 Valve
9
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