Replacing Packing - Emerson Fisher EHD Instruction Manual

EH (1-1/2x1 through 8x6)
July 2017

Replacing Packing

Key numbers referred to in this procedure are shown in figure 16 unless otherwise indicated.
1. Isolate the control valve from the line pressure, release pressure from both sides of the valve body, and drain the
process media from both sides of the valve.
Remove the cap screws in the stem connector, and separate the two halves of the stem connector. Then exhaust all
actuator pressure, if any was applied, and disconnect the actuator supply and any leakoff piping.
2. Remove either the yoke locknut (key 15) or the hex nuts (key 26), and remove the actuator from the bonnet (key 1).
3. Loosen the packing flange nuts (key 5) so that the packing is not tight on the valve plug stem (key 4, figure 18, 19,
or 20). Remove any travel indicator disk and stem locknuts from the valve plug stem threads.
Table 8. Torque for Body‐to‐Bonnet Bolting Using Anti‐Seize Lubricant(1)
VALVE
SIZE,
NPS
1, 1-1/2 x 1, 2x1
2, 3x2
3, 4x3
4, 6x4
6, 8x6
1. For other materials, contact your Emerson sales office
CAUTION
When lifting the bonnet (key 1), be sure that the valve plug and stem assembly (keys 3 and 4, figure 18, 19, or 20) remains
on the seat ring (key 6, figure 18, 19, or 20). This avoids damage to the seating surfaces as a result of the assembly dropping
from the bonnet after being lifted part way out. The parts are also easier to handle separately.
Use care to avoid damaging gasket sealing surfaces.
The EHD piston rings (key 8, figure 18) are brittle and in two halves. Avoid damaging the piston rings by dropping or rough
handling.
WARNING
If the cage adheres to the bonnet as the bonnet is lifted, secure the cage to the bonnet so that it will not cause personal
injury or equipment damage should it fall unexpectedly.
4. Unscrew the hex nuts (key 14, figure 18, 19, or 20) and carefully lift the bonnet off the valve stem. If present,
remove the Belleville washers (key 33, figure 17) and flat washers (key 29, figure 18, 19, 17, or 20). If the valve plug
and stem assembly starts to lift with the bonnet, use a brass or lead hammer on the end of the stem and tap it back
down. Set the bonnet on a cardboard or wooden surface to prevent damage to the bonnet gasket surface.
5. Remove the valve plug (key 3, figure 18, 19, or 20), the cage (key 2, figure 18, 19, or 20), and the top and bottom
cage gaskets (key 11, figure 18, 19, or 20).
8
VALVE
BODY
RATING
B7, B16, BD and 660 Studs
CL1500 163
CL2500 258
CL1500 258
CL2500 380
CL1500 556
CL2500 786
CL1500 786
CL2500 1058
CL1500 1383
CL2500 2807
or Local Business Partner for torques.
TORQUE
NSm
B8 and B8M Studs
122
195
195
285
420
597
597
800
1044
2102
Instruction Manual
LbfSFt
B7, B16, BD and 660 Studs B8 and B8M Studs
120
190
190
280
410
580
580
780
1020
2070
D100394X012
90
140
140
210
310
440
440
590
770
1550