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

ET Valve
November 2017
c. Disassemble the outer plug from the inner plug and install the seal over the inner plug, so that the seal rests
below the threaded area.
d. Thread the outer plug onto the inner plug and tighten with a strap wrench or similar tool until the alignment
marks line up. This will ensure that the plug parts are metal to metal and the seal is compressed properly. Do not
damage the outer plug guide surfaces.
e. Install set screws centering the inner plug in the outer plug and torque to 11 NSm (8 lbfSft).
f. Assemble the piston ring, anti‐extrusion rings, backup ring, and retainer.
6. For all constructions, place the gaskets (keys 12, 11 or 14 if used, and 10) and the shim (key 51) on top of the cage
or cage retainer. If there is a cage adaptor (key 4) or a bonnet spacer (key 32), set it on the cage or cage retainer
gaskets and place another flat sheet gasket (key 10) on top of the adaptor or spacer. If there is only a cage retainer,
place another flat sheet gasket on the retainer.
7. With an NPS 8 ET valve, install the load ring (key 26).
8. Mount the bonnet on the valve body and complete assembly according to steps 10 through 14 of the Replacing
Packing procedure. Be sure to observe the note prior to step 10.
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. With care, remove the valve plug and stem assembly from the valve body. If necessary, also lift out the cage.
CAUTION
To prevent possible product damage, cover the opening in the valve in the following procedure to protect the sealing
surfaces and to prevent foreign material from getting into the valve body cavity.
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 and valve plug 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. 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.
Table 6. Recommended Torque for ENVIRO‐SEAL Bellows Seal Packing Flange Nuts
VALVE STEM DIAMETER
VALVE SIZE, NPS
1 ‐ 2
3 ‐ 8
16
THROUGH PACKING
1/2
1
MINIMUM TORQUE
NSm LbfSin
2 22
5 44
Instruction Manual
D100398X012
MAXIMUM TORQUE
NSm LbfSin
4 33
8 67