Instruction Manual
D100391X012
EDR and ETR Valves
March 2016
5
Maintenance
WARNING
Avoid personal injury from sudden release of process pressure. Before performing any maintenance operations:
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Do not remove the actuator from the valve while the valve is still pressurized.
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Always wear protective gloves, clothing, and eyewear when performing any maintenance operations to avoid personal
injury.
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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.
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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.
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Vent the power actuator loading pressure and relieve any actuator spring precompression.
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Use lock‐out procedures to be sure that the above measures stay in effect while you work on the equipment.
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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.
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Check with your process or safety engineer for any additional measures that must be taken to protect against process
media.
Valve parts are subject to normal wear and must be inspected and replaced as necessary. Inspection and maintenance
frequency depends on the severity of service conditions. This section includes instructions for trim maintenance,
packing maintenance, and packing lubrication. All maintenance operations may be performed with the valve installed
in the pipeline.
Note
If the valve has ENVIRO‐SEAL
t
live‐loaded packing installed (figure 8, 9, or 10), see the Fisher instruction manual entitled
ENVIRO‐SEAL Packing System for Sliding‐Stem Valves (D101642X012)
for packing instructions.
Trim Maintenance
Disassembly
Note
Whenever a gasket seal is disturbed by removing or shifting gasketed parts, install a new gasket upon reassembly. This is necessary
to ensure a good gasket seal.
Key number locations are shown in figure 11 or 12 unless otherwise indicated.
