Installation Instructions
D101748X012
March 2021
Design A, E, EH, HP, YD, & YS
ENVIRO-SEAL
™
PTFE Packing
Design A, E, EH, HP, YD, and YS ENVIRO-SEAL
PTFE Packing for 3/8-inch and 1/2-inch Stem Sizes
Use these instructions to install ENVIRO‐SEAL packing
in valves that have standard packing or when
inspecting or replacing ENVIRO‐SEAL packing. For
additional information, see Fisher™ ENVIRO‐SEAL
Packing Systems for Sliding-Stem Valves Instruction
Manual (D101642X012
).
WARNING
Avoid personal injury or property damage from sudden
release of process pressure or uncontrolled movement
of parts. Before performing any maintenance
operations:
Disconnect any operating lines providing air pressure,
electric power, or a control signal to the actuator. Be
sure the actuator cannot suddenly open or close the
valve.
Use bypass valves or completely shut off the process to
isolate the valve from process pressure. Relieve process
pressure from both sides of the valve. Drain the process
media from both sides of the valve.
Vent the pneumatic actuator loading pressure and
relieve any actuator spring precompression. If a
spring-return actuator is used, be sure the actuator is
resting on its travel stop before disconnecting the stem
connector.
Use lock‐out procedures to be sure that the above
measures stay in effect while you work on the
equipment.
If you are installing the system in a valve that is still
connected to an actuator, remove the actuator from
the valve to provide sufficient space to install the
packing assembly. Refer to the appropriate valve and
actuator instruction manuals to remove the actuator.
1. Carefully remove the old packing parts from the
packing box. The surface condition of the valve
stem and the packing box wall is critical in obtaining
a good seal. If the valve stem needs to be replaced,
or any other valve part, refer to the appropriate
valve instruction manual for replacement
procedures. Complete all valve maintenance before
installing the ENVIRO‐SEAL packing system into the
bonnet.
2. If a retrofit kit is being installed in place of the
original packing, it may be necessary to remove the
old studs from the valve because they are too short.
Check stud length by installing the packing and the
spring pack assembly using the following assembly
procedures, and try installing the packing nuts. If
the packing nuts will not start on the threads of the
studs, it will be necessary to install new studs and
nuts from the retrofit kit.
Note
Ensure that the packing box parts are assembled in the
correct order. Packing parts can not function properly if the
Belleville springs or other packing parts are not stacked
correctly.
3. Use the drawing provided to ensure that the
packing parts are assembled in the correct order.
Install the ENVIRO‐SEAL packing parts into the
packing box.
4. Install the spring pack assembly (key 217), which
includes the attached springs, and packing flange
(key 201), on the stem. Install the nuts and hand
tighten them.
Note
Lubrication is required for the packing studs and nuts.
Although it is important to properly lubricate the stud
threads and internal nut threads, it is also important to
properly lubricate the contacting face of the nut.
5. You will obtain maximum benefit from your
ENVIRO‐SEAL packing system when you tighten the
packing flange nuts and compress the Belleville
springs to their “target load.” The target load is the
point where the Belleville springs are designed for
optimum performance, when they are compressed
to 85% of their maximum deflection, or nearly flat.
(Maximum deflection is when the springs are 100%
www.Fisher.com
Design A, E, EH, HP, YD, & YS
ENVIRO-SEAL PTFE Packing
Installation Instructions
D101748X012
March 2021
compressed, or completely flat.)
To obtain the target load of 85% compression of
maximum deflection, perform the following:
D Tighten the packing flange nuts alternately and
evenly, keeping the packing flange parallel with
the valve flange, until the Belleville springs are
compressed 100% (or completely flat). Refer to
the ENVIRO‐SEAL Packing Instruction Manual
(D101642X012
) for more information.
D For PTFE packing, loosen each packing flange nut
1/2 turn (180 degrees rotation). The “target
load” of 85% compression has now been
reached.
6. Refer to the appropriate valve and actuator
instruction manuals when connecting the valve to
PACKING FLANGE
(KEY 201)
SPRING PACK
ASSEMBLY
(KEY 217)
the actuator. Under normal conditions, the packing
nuts should not require re‐tightening.
Packing Kits
PACKING RETROFIT PACKING REPAIR
RPACKXRTX012 RPACKX00192 3/8 (9.5)
RPACKXRTX022 RPACKX00202 1/2 (12.7)
For additional information concerning the installation
of this packing kit, please consult the appropriate
product instruction manual.
Stems and packing box constructions that do not meet
Emerson stem finish specifications, dimensional
tolerances, and design specifications, may adversely
alter the performance of this packing kit.
STEM SIZE
DIAMETER,
inches (mm)
PACKING SET,
QTY 2
(KEY 215)
LANTERN RING
(KEY 216)
ANTI-EXTRUSION
WASHER, QTY 4
(KEY 214)
PACKING BOX RING
(KEY 211)
LOWER WIPER
(KEY 218)
32B7849‐A
Neither Emerson, Emerson Automation Solutions, nor any of their affiliated entities assumes responsibility for the selection, use or maintenance
of any product. Responsibility for proper selection, use, and maintenance of any product remains solely with the purchaser and end user.
ENVIRO-SEAL and Fisher are marks owned by one of the companies in the Emerson Automation Solutions business unit of Emerson Electric Co. Emerson
Automation Solutions, Emerson, and the Emerson logo are trademarks and service marks of Emerson Electric Co. All other marks are the property of their
respective owners.
The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not
to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. All sales are
governed by our terms and conditions, which are available upon request. We reserve the right to modify or improve the designs or specifications of such
products at any time without notice.
Emerson Automation Solutions
Marshalltown, Iowa 50158 USA
Sorocaba, 18087 Brazil
Cernay, 68700 France
Dubai, United Arab Emirates
Singapore 128461 Singapore
www.Fisher.com
3/8-INCH (9.5 mm)
1/2-INCH (12.7 mm)
STEM SIZES
FEMALE ADAPTOR
PACKING RING
MALE ADAPTOR
2
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