VALVE
INCHES
Inch
mm
1, 1 1/2
Installation Instructions
Design CP PTFE Packing
Use these instructions when inspecting or replacing
standard PTFE packing.
WARNING
Avoid personal injury or property damage from sudden release of process
pressure or bursting of parts. Before
performing any maintenance operations:
D 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.
D 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.
D Vent the pneumatic actuator loading pressure and relieve any actuator
spring precompression.
D 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. If a spring-return actuator is used, it is
possible that disconnecting the stem connector will
allow the spring to force the actuator to the end of its
travel. Be sure the actuator spring is resting on its
travel stop. Refer to the appropriate valve and actuator
instruction manuals to remove the actuator.
1. Remove the packing flange nuts, packing flange,
and bushing (keys 212, 201, and 208). Carefully push
out all the remaining packing box parts from the bonnet using a rounded rod or other tool that will not
scratch the packing box wall or lower guide bushing.
Clean the packing box and the metal packing box
parts.
2. Inspect the valve stem threads and packing box
surfaces for any sharp edges that might cut the packing. Scratches or burrs could cause packing box leakage or damage to the new packing. If the surface
condition cannot be improved by light sanding, replace
the damaged parts.
3. Install new packing and the metal packing box
parts according to the appropriate arrangement in figure 1. Place a smooth-edged pipe over the valve
stem, and gently tap each soft packing part into the
packing box, being sure that air is not trapped between adjacent soft parts.
4. Slide the bushing and packing flange (keys 208
and 201) into position. Lubricate the packing flange
studs (key 200) and the faces of the packing flange
nuts (key 212). Replace the packing flange nuts, but
do not tighten.
5. For PTFE packing, tighten the packing flange nuts
alternately in small equal increments until one of the
nuts reaches the minimum recommended torque
shown in table 1. Then, tighten the remaining flange
nuts until the packing flange is level and at a 90-degree angle to the valve stem.
6. Mount the actuator on the valve assembly, and reconnect the actuator and valve stem. Refer to the appropriate valve and actuator instruction manuals when
connecting the valve to the actuator. Check for leakage around the packing follower when the valve is being put into service. Retighten the packing flange nuts
as required.
For additional information concerning the installation of
this packing kit, please consult the appropriate Fisher
Controls product instruction manual.
Table 1. Recommended Torque for Packing Flange Nuts
VALVE STEM
VALVE
SIZE,
INCHES
1, 1-1/2,
3, 4 3/4 19.1
DIAMETER
Inch mm
,
1/2 12.7
2
2 5/8 15.9
ANSI
CLASS
150 15 1.7 23 2.6
300 20 2.3 31 3.5
150 12 1.4 19 2.1
300 17 1.9 25 2.8
150 31 3.5 47 5.3
300 42 4.8 63 7.2
PTFE TYPE PACKING
Minimum
Torque
LbfSin NSm LbfSin NSm
Maximum
Torque
Fisher, Fisher-Rosemount, and Managing The Process Better are marks owned by Fisher Controls
International, Inc. or Fisher-Rosemount Systems, Inc.
All other marks are the property of their respective owners.
EFisher Controls International, Inc. 1995, 1997; All Rights Reserved
D300907X012 10/97
Installation Instructions
Design CP PTFE Packing
PACKING REPAIR STEM SIZE DIAMETER, IN. (mm)
RCPXPACK012 1/2 (12.7)
RCPXPACK222 5/8 (15.9)
RCPXPACK022 3/4 (19.1)
Packing Stud - Not Shown
(Key 200)
Packing Flange Nuts - Not Shown
(Key 212)
Packing Flange - Not Shown
(Key 201)
Bushing
(Key 208)
Packing Set
(Key 215)
Lantern Ring
(Key 216)
Packing Set
(Key 215)
Bushing
(Key 208)
1/2, 5/8-Inch 3/4-Inch
Figure 1. PTFE V-RING WITH ONE-PIECE BUSHING
Stems and packing box constructions that do not meet Fisher Controls stem finish specifications, dimensional
tolerances, and design specifications, may adversely alter the performance of this packing kit.
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. We reserve the right to modify or improve the designs or specifications of such products at any time without notice.
For information, contact Fisher Controls:
Marshalltown, Iowa 50158 USA
Cernay 68700 France
Sao Paulo 05424 Brazil
Singapore 0512
2
Printed in U.S.A.
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