Fisher 9500 - Manual (Page 7)

9500 Valve
Instruction Manual
Form 2433
November 2007
7
Figure 5. Tandem Linkage Adjustment for
Three-Way Valve Assemblies
B2144-1 / IL
locknuts on the tandem linkage when adjustment is
complete.
Maintenance
Use table 4 to locate and correct possible leakage or
mechanical linkage problems with the valve.
WARNING
Avoid personal injury from sudden
release of process pressure. Before
performing any maintenance
operations:
D Always wear protective gloves,
clothing, and eyewear when
performing any maintenance
operations to avoid personal injury.
D Disconnect any operating lines
providing air pressure, electric power,
or a control signal to the actuator. Be
sure the actuator cannot suddenly
open or close the valve.
D Use bypass valves or completely
shut off the process to isolate the
valve from process pressure. Relieve
process pressure on both sides of the
valve. Drain the process media from
both sides of the valve.
D Vent the power actuator loading
pressure and relieve any actuator
spring precompression.
D Use lock-out procedures to be
sure that the above measures stay in
effect while you work on the
equipment.
D The valve packing box may
contain process fluids that are
pressurized, even when the valve has
been removed from the pipeline.
Process fluids may spray out under
pressure when removing the packing
hardware or packing rings, or when
loosening the packing box pipe plug.
D Check with your process or safety
engineer for any additional measures
that must be taken to protect against
process media.
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.
Disassembly
Key numbers locations are shown in figure 7.
1. Loosen all flange studs or bolts. Remove all but
the bottom flange studs or bolts.
CAUTION
To avoid damage to the valve disc
caused by the disc hitting the mating
flange, be certain the disc is closed
before removing the valve from the
pipeline.
2. If necessary, pry flanges apart so that liner faces
will not be damaged when the valve is being
removed. Inspect the disc (key 3) and liner (key 2)
for wear or damage.
3. Remove the actuator from the valve. Follow
instructions in the appropriate actuator instruction
manual.
4. From both sides of valve, unscrew thrust-plate
cap screws (key 10) and remove thrust plates
(key 9).