Packing Lubrication; Packing Maintenance; Adding Packing Rings - Fisher HPA Instruction Manual

HP and HPA Valves
July 2017

Packing Lubrication

CAUTION
Do not lubricate graphite packing. Graphite packing is self-lubricated. Additional lubrication may result in slip-stick
movement of the valve.
Note
To avoid lubricants breaking down at elevated temperatures, do not lubricate packing used in processes with temperatures over
260_C (500_F).
WARNING
Do not lubricate parts when used in oxygen service, or where the lubrication is incompatible with the process media. Any
use of lubricant can lead to the sudden explosion of media due to the oil/oxygen mixture, causing personal injury or
property damage.
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 pipe plug (key 31, figure 17, 18, or 19). Use a good quality silicon‐base
lubricant. Packing used in oxygen service or in processes with temperatures over 260_C (500_F) should not be
lubricated. 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

If there is undesirable packing leakage in the spring‐loaded PTFE V‐ring packing shown in figure 3, tighten the packing
flange nuts (key 21, figure 17, 18, or 19) until the shoulder on the packing follower (key 28, figure 17, 18, or 19)
contacts the bonnet (key 18, figure 17, 18, or 19). If leakage continues, replace the packing by following the
numbered steps presented in the replacing packing procedure.
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 21, figure 17, 18, or 19) 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 new
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.

Adding Packing Rings

Key numbers referred to in this procedure are shown in figure 17, 18, or 19, unless otherwise indicated.
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Instruction Manual
D101634X012