Trim Maintenance - Fisher EWS Series Instruction Manual

Instruction Manual
Form 2376
March 2007
VALVE SIZE NPS VALVE SIZE, NPS
4x2
6x4 or 8x4
8x6 8x6
10x8
12x6
12x8 12x8
1. Determined from laboratory tests.
VALVE STEM VALVE STEM
PRESSURE PRESSURE
DIAMETER
RATING RATING
mm Inches
12.7
1/2 1/2
12.7
19.1
3/4 3/4
19.1
25.4
1 1
25.4
31.8
1 1/4 1-1/4
31.8
13. Slide the packing follower, upper wiper, and
packing flange (keys 13, 12, and 3, figure 21) into
position. Lubricate the packing flange studs (key 4,
figure 21) and the faces of the packing flange nuts
(key 5, figure 21). Install the packing flange nuts.
14. For spring-loaded PTFE V-ring packing,
tighten the packing flange nuts until the shoulder on
the packing follower (key 13, figure 21) contacts the
bonnet.
For graphite packing, tighten the packing flange
nuts to the maximum recommended torque shown in
table 6. Then, loosen the packing flange nuts, and
retighten them to the recommended minimum torque
shown in table 6.
For ENVIRO-SEAL or HIGH-SEAL live-loaded
packing, refer to the note at the beginning of the
Packing Maintenance section.
For other packing types, tighten the packing flange
nuts alternately in small equal increments until one
of the nuts reaches the minimum recommended
torque shown in table. Then, tighten the remaining
flange nuts until the packing flange is level and at a
90-degree angle to the valve stem.
15. Mount the actuator on the valve assembly, and
reconnect the actuator and valve stem according to
Table 5. Body-to-Bonnet Bolt Torque Guidelines
CL300 or CL600
CL900
CL300 or CL600
CL900
Table 6. Recommended Torque for Packing Flange Nuts
GRAPHITE TYPE PACKING
Minimum Torque
NSm LbfSIn
CL300 7 59
CL600 9 81
CL300 15 133
600 21 182
CL
300 26 226
CL
CL 600 35 310
300 36 318
CL
CL 600 49 437
BOLT TORQUES
NSm
102
259
548
1315
745
548
732
2712
Maximum Torque Minimum Torque
NSm LbfSIn NSm
10 88 3
14 122 4
23 199 7
31 274 10
38 339 12
53 466 17
54 477 17
74 655 24
the procedure in the appropriate actuator instruction
manual.

Trim Maintenance

Observe the warning at the start of the
Maintenance section.
In the following applicable procedures,
to avoid damaging parts, do not grip
the bellows shroud or other parts of
the stem/bellows assembly. Grip only
the flat areas on the stem where it
extends out of the top of the bellows
shroud.
For C-seal construction, see the appropriate C-seal
sections in this instruction manual.
Except where indicated, key numbers in this section
are referenced in figure 22 for Design EWD
constructions, figure 22 for restricted trim detail,
figure 23 for Design EWS constructions, and
EW Valve
(1)
LbfSft
75
191
404
970
550
404
540
2000
PTFE TYPE PACKING
Maximum Torque
LbfSIn NSm
28 5
39 7
64 11
87 15
108 18
149 25
152 26
209 36
WARNING
CAUTION
LbfSIn
42
58
95
131
162
223
228
314
11