Emerson Fisher POSI-SEAL A31A Instruction Manual page 19

Instruction Manual
D500240X012
1. Remove the actuator and valve, as an assembly, from the pipeline, and then remove the actuator from the valve.
Note
It is not necessary to remove the retaining ring and seal ring when removing the shaft(s) and disk.
2. Secure the valve in an upright position. Rotate the disk (key 2) 180 degrees counterclockwise from the fully closed
position by manually turning the drive shaft.
3. Removing the Anti‐Blowout Protection (refer to figure 7):
a. For PTFE or Graphite Packing: Remove the hex nuts and pull off the packing flange. Remove the hex jam nuts and
the anti‐blowout flange. Remove the packing follower.
b. For ENVIRO‐SEAL Packing System: Evenly loosen and remove the two packing hex nuts, the packing flange, the
spring stack, the two hex jam nuts, the anti‐blowout flange, and the packing follower.
4. Remove the anti‐blowout ring from around the drive shaft using a needle nose pliers.
Note
NPS 3 through 12 valves (CL150 and 300) have a bearing stop (key 8, figure 8) pressed into the bearing bore immediately after the
packing box.
Do not attempt to remove the bearing stop which is found in the drive shaft bearing bore immediately after the packing box. The
bearing stop is pressed into the bearing bore. If the bearing stop needs replacement, contact your
information.
5. Remove the packing from around the drive shaft.
Note
Different valves require slightly different procedures because different valve sizes/ pressure classes have different methods of
connecting the disk and shaft(s). To identify the proper procedures, refer to the list below.
D
CL150, NPS 3 through 8: One‐piece shaft with 1 taper key.
D
CL150, NPS 10 and 12: Two‐piece shaft. 1 taper key in the drive shaft; 1 disk pin in the follower shaft.
D
CL300, NPS 3 through 6: One‐piece shaft with 1 taper key.
D
CL300, NPS 8 and 10: Two‐piece shaft. 1 taper key in the drive shaft; 1 disk pin in the follower shaft.
D
CL300, NPS 12: Two‐piece shaft with 2 tangential pins in the drive shaft; 1 disk pin in the follower shaft.
6. Proceed as appropriate, using the following instructions.
For valves with taper key(s), locate the taper key(s) (key 9, figure 8) which runs through the drive shaft boss on the
back of the valve disk. Using a pin punch on the smaller end of the key, drive it out of the disk and shaft. Driving a taper
key in the wrong direction will tighten it.
Note
Certain valve sizes may have a taper key that is arc spot welded in place. To remove the key, use a punch on the smaller end of the
taper key and drive it out of the disk and shaft, breaking the weld.
A31A Valve
February 2019
Emerson sales office for more
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