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Design V260
Maintenance
Valve parts are subject to normal wear and must be
inspected and replaced as necessary. The frequency
of inspection and replacement depends upon the se-
verity of service conditions. Because of the care Fisher
Controls takes in meeting all manufacturing require-
ments (heat treating, dimensional tolerances, etc.),
use only replacement parts manufactured or furnished
by Fisher Controls.
Key numbers are shown in figure 6, unless otherwise
noted.
WARNING
Avoid personal injury or equipment dam-
age from sudden release of process
pressure or uncontrolled movement of
parts. Before performing any mainte-
nance operations:
D Disconnect any operating lines pro-
viding air pressure, electric power, or a
control signal to the actuator. Be sure
the actuator cannot suddenly open or
close the valve.
D Vent the power actuator loading
pressure and relieve any actuator spring
precompression.
D Use bypass valves or completely
shut off the process to isolate the valve
from process pressure. Relieve process
pressure from both sides of the valve.
Drain the process media from both sides
of the valve.
D Dual-seal valve constructions can
retain pressure and process fluid even
after process pressure has been re-
moved from both sides of the valve. Re-
lieve this pressure before disassembling
or removing the valve from the line.
Take additional care if the process fluid
is hot, flammable, caustic, or toxic.
D Carefully secure the valve in an up-
right position. The roundness of the
flanges and valve body allow it to easily
roll from side-to-side. The combined
weight of the valve/actuator assembly
could cause injury or property damage
when falling to the side.
D Use lock-out procedures to be sure
that the above measures stay in effect
while you work on the equipment.
4
D Avoid injury by keeping hands,
tools, and other objects away from the
ball while stroking the valve.
Packing Maintenance
For the ENVIRO-SEAL Packing System,
refer to the separate ENVIRO-SEAL
Packing System for V-Line and edisc
Rotary Valves instruction manual for
maintenance instructions.
Stopping Leakage
For standard PTFE V-ring packing, leakage around the
packing follower may be stopped by tightening the
packing follower nuts.
If the packing is relatively new and tight on the drive
shaft, and if tightening the packing follower nuts does
not stop the leakage, the drive shaft may be worn or
nicked so that a seal cannot be made. If the leakage
comes from the outside diameter of the packing, the
leakage may be caused by nicks or scratches on the
packing box wall. Inspect the drive shaft and packing
box wall for nicks or scratches while performing the
following procedure.
Replacing Packing
Replacing the packing requires bleeding off the system
and removing the actuator from the valve. Valve/actua-
tor adjustments cannot be made correctly without ob-
serving the fully open or closed position of the ball (key
11). It is not necessary to remove the valve from the
pipeline, if care is taken to note the position and align-
ment of the lever and shaft and to not disturb the turn-
buckle position.
Disassembly
1. Isolate the control valve from the line pressure, re-
lease pressure from both sides of the valve body, and
drain the process media from both sides of the valve. If
using a power actuator, shut off all pressure lines (or
other power source) to the power actuator, release
pressure from the actuator, and disconnect the pres-
sure lines from the actuator. Use lock-out procedures
to be sure that the above measures stay in effect while
you work on the equipment.
See the WARNING at the beginning of the Mainte-
nance section for more information before removing
the valve from the pipeline.
2. Remove line bolting, remove the control valve from
the pipeline, and place the actuator/valve assembly on
a flat surface.
Note
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