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Instruction Manual
D100394X012
WARNING
Personal injury could result from packing leakage. Valve packing was tightened prior to shipment; however some
readjustment will be required to meet specific service conditions. Check with your process or safety engineer for any
additional measures that must be taken to protect against process media.
Packing Lubrication
CAUTION
Do not lubricate graphite packing. Graphite packing is self-lubricated. Additional lubrication may result in slip-stick
movement of the valve.
WARNING
To avoid personal injury or property damage resulting from fire or explosion, do not lubricate packing used in oxygen
service or in processes with temperatures over 260_C (500_F).
A lubricator or lubricator/isolating valve (figure 2) is recommended for PTFE‐composition packing. The lubricator or
lubricator/isolating valve is installed in place of the pipe plug (key 14, figure 16). It is recommended that a good quality
silicon‐base lubricant be used. To operate the lubricator, simply turn the cap screw clockwise to force 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
If there is undesirable packing leakage in spring‐loaded PTFE V‐ring packing (figure 4), tighten the packing flange nuts
(key 5, figure 16) until the shoulder on the packing follower (key 13, figure 16) contacts the bonnet (key 1, figure 16).
If leakage continues, replace the packing by following the numbered steps presented in the Replacing Packing
procedure.
CAUTION
When tightening packing flange nuts, do not exceed the maximum recommended torque in table 7 or excessive friction
may result, resulting in keeping the valve from stroking fully and not attaining proper seat load.
If there is undesirable packing leakage with other than spring‐loaded PTFE V‐ring packing, first try to limit the leakage
and establish a stem seal by tightening the packing flange nuts (key 5, figure 16) to at least the minimum
recommended torque in table 7. However, do not exceed the maximum recommended torque in table 7 or excessive
friction may result. If leakage continues, replace the packing by following the numbered steps presented in the
Replacing Packing procedure.
If the packing is relatively new and tight on the valve plug stem, and if tightening the packing flange nuts does not stop
the leakage, it is possible that the stem is worn or nicked so that a seal cannot be made. The surface finish of a 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. While replacing the packing according to
the Replacing Packing procedure, inspect the valve plug stem and packing box wall for nicks or scratches.
EH (1-1/2x1 through 8x6)
July 2017
7
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