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Instruction Manual
D103553X012
Packing Lubrication
CAUTION
Do not lubricate graphite packing. Graphite packing is self-lubricated. Additional lubrication may result in slip-stick
movement of the valve.
If a lubricator or lubricator/isolating valve (figure 2) is provided for PTFE/composition or other packings that require
lubrication, it will be installed in place of the 1/4 NPT pipe plug (key 14, figure 4). Use a silicon-base lubricant. To
operate the lubricator, turn the cap screw clockwise to force the lubricant into the packing box. The
lubricator/isolating valve operates the same way except the isolating valve must first be opened and then closed after
lubrication is completed.
Packing Maintenance
This procedure does not cover ENVIRO-SEAL or HIGH-SEAL packing; refer to separate manuals for instructions on those
packing types.
Key numbers are shown in figure 3 unless otherwise indicated.
For spring-loaded single PTFE V-ring packing, the spring (key 8) maintains a sealing force on the packing. If leakage is
noted around the packing follower (key 13), check to be sure the shoulder on the packing follower is touching the
bonnet. If the shoulder is not touching the bonnet, tighten the packing flange nuts (key 5, figure 4) until the shoulder
is against the bonnet. If leakage cannot be stopped in this manner, proceed to the Replacing Packing section.
If there is undesirable packing leakage with other than spring-loaded packing, first try to limit the leakage and
establish a stem seal by tightening the packing flange nuts.
If the packing is relatively new and tight on the stem and if tightening the packing flange nuts does not stop the
leakage, it is possible that the valve stem is worn or nicked so that a seal cannot be made. The surface finish of a new
valve stem is critical for making a good packing seal. If the leakage comes from the outside diameter of the packing, it
is possible that the leakage is caused by nicks or scratches around the packing box wall. If performing any of the
following procedures, inspect the valve stem and packing box wall for nicks and scratches.
Replacing Packing
1. Isolate the control valve from the line pressure, release pressure from both sides of the valve body, and drain the
process media from both sides of the valve. If using a power actuator, also shut off all pressure lines to the power
actuator, release all pressure from the actuator, and use lock-out procedures to prevent injury while you work on
the equipment.
2. Remove any leak-off piping from the bonnet. Disconnect the stem connector, and then remove the actuator from
the valve by unscrewing the hex nuts (key 26, figure 4).
3. Loosen the packing flange nuts (key 5, figure 4) so that the packing is not tight on the valve stem. Remove any
travel indicator parts and stem locknuts from the valve stem threads.
Large ET and ED Valves
July 2014
7
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