Instruction Manual
D101642X012
ENVIRO-SEAL Sliding-Stem Valves
July 2017
6
Table 7. Graphite ULF Packing Torque
(1)
STEM SIZE
TORQUE
mm
Inch
N
S
m
lbf
S
in
lbf
S
ft
9.5
3/8
4.3
38
3.2
12.7
1/2
8.5
76
6.3
19.1
3/4
21
187
16
25.4
1
47
420
35
31.8
1
-
1/4
56
495
41
1. For A, DBQ, easy
-
e, EH, FB, HP, YD, and YS valves.
CAUTION
To prevent product damage caused by scratching or damaging the packing box wall, take care when removing the old
packing parts from the packing box.
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 ENVIRO
-
SEAL packing system into the bonnet.
Note
ENVIRO
-
SEAL PTFE packing systems can be used in either vacuum or positive pressure service. It is not necessary to reverse
ENVIRO
-
SEAL packing components in vacuum service.
Note
Ensure that the Belleville springs are stacked properly (see figure 4) and packing box parts are assembled in the correct order (see
figures 5, 6, or 7). Packing parts cannot function properly if the Belleville springs or other packing parts are not stacked correctly.
ENVIRO
-
SEAL packing parts into the packing box.
4. Install the spring pack assembly (key 217), with the attached springs, onto the stem.
5. Install the packing flange (key 201) and packing box nuts (key 212). Hand tighten them.
Note
In general, the following tightening procedure applies to all ENVIRO
-
SEAL packing systems
--
both sliding
-
stem and rotary.
Note
Lubrication is required for the packing studs and nuts.
Although it is important to properly lubricate the stud threads and internal nut threads, it is also important to properly lubricate
the contacting face of the nut. See figures 5, 6, or 7 for lubrication locations.
