Enviro-Sealt Bellows Seal Bonnet; Replacing A Plain Or Extension Bonnet With An Enviro-Seal Bellows Seal Bonnet (Stem/Bellows Assembly) - Emerson Fisher EAD Instruction Manual

ED Valve
November 2017
4. Apply a suitable high‐temperature lubricant to the threads on the plug. Then, place the C‐seal retainer onto the
plug and tighten the retainer using an appropriate tool such as a strap wrench.
5. Using an appropriate tool such as a center punch, stake the threads on top of the plug in one place (figure 9) to
secure the C‐seal retainer.
6. Replace the piston ring(s) following instructions in the Trim Replacement section of this manual.
7. Return the seat ring, cage, plug/retainer assembly, and stem to the valve body and completely reassemble the valve
package following the appropriate instructions in the Trim Replacement section of this manual.
CAUTION
To avoid excessive leakage and seat erosion, the valve plug must be initially seated with sufficient force to overcome the
resistance of the C‐seal plug seal and contact the seat ring. You can correctly seat the valve plug by applying the full
actuator load. This force will adequately drive the valve plug to the seat ring, thus giving the C‐seal plug seal a
predetermined permanent set. Once this is done, the plug/retainer assembly, the cage, and the seat ring become a
matched set.
With full actuator force applied and the valve plug fully seated, align the actuator travel indicator scale with the lower
end of valve travel. Refer to the appropriate actuator instruction manual for information on this procedure.
ENVIRO‐SEAL Bellows Seal Bonnet
Replacing a Plain or Extension Bonnet with an ENVIRO‐SEAL Bellows Seal Bonnet
(Stem/Bellows Assembly)
1. Remove the actuator and bonnet according to steps 1 through 5 of the Replacing Packing procedure in the
Maintenance section.
2. Lift out the cage.
3. Remove and discard the existing bonnet gasket. Cover the valve body opening to protect sealing surfaces and to
prevent foreign material from entering the valve body cavity.
Note
The ENVIRO‐SEAL stem/bellows assembly for easy‐e valves is available only with a threaded and drilled plug/adaptor/stem
connection. The existing valve plug can be reused with the new stem/bellows assembly or a new plug can be installed.
4. Inspect the existing valve plug. If the plug is in good condition, it can be reused with the new ENVIRO‐SEAL
stem/bellows assembly. To remove the existing valve plug from the stem, first, place the existing plug stem
assembly in a soft‐jaw chuck or other type of vise so that the jaws grip a portion of the valve plug that is not a
seating surface. Drive out or drill out the pin (key 8).
5. Then, reverse the plug stem assembly in the soft‐jaw chuck or vise. Grip the valve stem in an appropriate place and
unscrew the existing plug from the valve stem.
CAUTION
When installing a valve plug on the ENVIRO‐SEAL stem/bellows assembly, the valve stem must not be rotated. Damage to
the bellows may result.
Do not grip the bellows shroud or other parts of the stem/bellows assembly. Grip only the flat areas on the stem where it
extends out of the top of the bellows shroud.
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Instruction Manual
D100390X012