Instruction Manual
D100392X012
EH Valves NPS 8 through 14
June 2017
7
A lubricator or lubricator/isolating valve (figure 2) is recommended for PTFE‐impregnated composition packing. The
lubricator or lubricator/isolating valve is installed in place of the pipe plug in the bonnet. Use a good quality
silicon‐base lubricant. Do not lubricate packing used in oxygen service or in processes with temperatures over 260
_
C
(500
_
F). To operate the lubricator, turn the cap screw clockwise to force lubricant into the packing box. The
lubricator/isolating valve operates the same way except open the isolating valve before turning the cap screw and then
close the isolating valve after lubrication is completed.
Packing Maintenance
WARNING
Personal injury could result from packing leakage. Valve packing was tightened before shipment; however, the packing
might require readjustment to meet specific service conditions.
Valves with ENVIRO‐SEAL live‐loaded packing or HIGH‐SEAL live‐loaded packing installed probably will not require this
initial re‐adjustment. See the Fisher instruction manuals titled ENVIRO‐SEAL Packing System for Sliding‐Stem Valves
(
) or HIGH‐SEAL Live‐Loaded Packing System (
) (as appropriate) for packing instructions.
To convert an existing packing arrangement to ENVIRO‐SEAL packing, refer to the retrofit kits listed in the parts kit
sub‐section near the end of this manual. Figure 10 shows typical ENVIRO‐SEAL packing systems.
For spring‐loaded PTFE V‐ring packing (figure 4), the spring maintains a sealing force on the packing. If leakage is
noted around the packing follower (key 13, figure 11), check to be sure the shoulder on the packing follower is
touching the bonnet (key 1, figure 11). If the shoulder is not touching the bonnet, tighten the packing flange nuts (key
5, figure 11) until the shoulder on the packing follower is against the bonnet. If the packing leakage is still excessive,
replace the packing by following the Replacing Packing procedure.
If packing leakage is undesirable 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 11) to at least the minimum recommended
torque in table 5. However, do not exceed the maximum recommended torque in table 5 or excessive friction may
result.
Table 5. Recommended Packing Flange Nut Torques
STEM DIAMETER
VALVE
RATING
N
S
m
Lbf
S
ft
mm
Inches
Min
Max
Min
Max
31.8
1‐1/4
CL1500
68
102
50
75
CL2500
81
122
60
90
50.8
2
CL1500
98
146
72
108
CL2500
115
170
85
125
If the packing is relatively new and tight on the stem, and if tightening the packing flange nuts does not stop the
leakage, the valve stem may be 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, the leakage
may be caused by nicks or scratches around the packing box wall. While replacing the packing according to the
Replacing Packing procedure, inspect the stem and packing box wall for nicks or scratches.
Replacing Packing
WARNING
Refer to the WARNING at the beginning of the Maintenance section in this instruction manual.