Emerson Fisher POSI-SEAL A81, Инструкция по эксплуатации

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Instruction Manual
D103302X012
A81 Valve
January 2011
14
1. Isolate the control valve from the line pressure, release pressure from both sides of the valve body, and drain the
process media from both sides of the valve. If using a power actuator, also shutoff all pressure lines to the power
actuator, release all pressure from the actuator. Use lock‐out procedures to be sure that the above measures stay in
effect while you work on the equipment.
CAUTION
When removing the actuator in the following step, use a wheel puller to separate the actuator parts from the valve shaft.
Do not drive the actuator parts off the valve shaft because this could damage valve trim components.
2. Remove the actuator per instructions in separate actuator instruction manuals, then remove the cap screws and
nuts (keys 35 and 36). Remove the clamp (key 130, figure 3) if the strap (key 131, figure 3) is used.
3. Remove the packing flange nuts and the packing flange (key 26) if used and pull out the packing follower (key 25).
Table 7. Recommended Blind Flange Bolt Torque
VALVE SIZE TORQUE
DN NPS N
S
m lbf
S
ft
50 to 150 2 to 6 9.5 7.0
200, 250 8, 10 23 17
300 12 45 33
Disassembly
1. Remove the seal ring assembly according to steps 3 and 4 of the Replacing Seal Ring section on page 12 of this
manual.
2. Remove hex nuts, blind flange, gasket, spacer (if present), follower spring seats, and follower spring (keys 19, 17,
16, 15, 9, and 12).
3. Clean the gasket surfaces on the blind flange (key 17) and on the end of the valve body (key 1).
4. Rotate the disk (key 3) to the fully open position.
5. Refer to figure 6 and determine the location of the smaller end of the taper pins (key 8). Drive out the taper pins
and expansion pins (key 7) towards the larger end.
WARNING
Once the shafts have been removed in the following step, the disk may fall from the valve body. To avoid personal injury and
disk damage, support the disk to prevent it from falling as the shafts are being removed.
6. Pull the follower shaft (key 11) out through the outboard end of the valve body. If the follower shaft cannot be
pulled free, the end of the follower shaft is internally threaded (see table 6) for screwing in a bolt or stud to aid in
pulling the follower shaft.
7. Pull the drive shaft (key 10) out through the actuator end of the valve body and remove the anti‐blowout fing (key
40) from the drive shaft.
8. Remove the disk (key 3) from the valve body.
9. Remove the packing (key 24, figure 4) and the packing box ring (key 23, figure 4).
10. If either of the bearings (key 6) require replacement, remove them.
11. Clean the packing box and [metal packing box parts].