
Instruction Manual
D104566X012
Maintenance Packing System for Sliding-Stem Valves
October 2020
3
Installation
If you are changing the packing system, it is good practice to review actuator sizing, as packing friction will change.
See tables 3 and 4 for information on packing friction.
WARNING
Avoid personal injury from sudden release of process pressure or uncontrolled movement of parts. Before performing any
maintenance operations:
D Do not remove the actuator from the valve while the valve is still pressurized.
D Always wear protective gloves, clothing, and eyewear when performing any maintenance operations to avoid personal
injury.
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 power 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.
D The valve packing box may contain process fluids that are pressurized, even when the valve has been removed from the
pipeline. Process fluids may spray out under pressure when removing the packing hardware or packing rings, or when
loosening the packing box pipe plug.
D Check with your process or safety engineer for any other hazards that may be present from exposure to process media.
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.
Remove old packing parts from the packing box by using the valve instruction manual procedures. Both the valve stem
surface condition and the packing bore are critical in obtaining a good seal. If the valve stem surface is scratched,
nicked, or worn, replace the valve stem before installing the Maintenance Packing System. Check the condition of the
packing bore and clean or hone it out, as necessary. Refer to the appropriate valve instruction manual to replace the
valve stem.
Then proceed as follows:
1. The original packing flange studs used for standard packing arrangements should be long enough to accommodate
the retrofit kit parts. If you determine that the existing studs and nuts should be replaced however, due to their
condition, replace them with the studs and nuts (keys 200 and 212) specified in the parts section of this manual.
2. Carefully remove the old packing parts from the packing box. If the valve stem or packing box wall is scratched or
damaged, it can cause excessive leakage. 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 Maintenance Packing System into the bonnet.
Table 3. Packing Friction at Ambient Temperature
VALVE STEM DIAMETER MAINTENANCE PACKING
mm Inches Newtons Pounds (Force)
12.7
19.1
25.4
31.8
1/2
3/4
1
1-1/4
1980
4580
7250
9470
445
1030
1630
2130