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Instruction Manual
D103302X012
WARNING
Avoid personal injury and property damage from sudden release of process pressure or bursting of parts. Before performing
any maintenance operations:
D Do not remove the actuator from the valve while the valve is still pressurized.
D Always wear protective gloves, clothing, and eyewear when performing any maintenance operations.
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 spring precompression.
D Use lock‐out procedures to be sure 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 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.
Packing Maintenance
Refer to figure 4 for available packing configurations. All maintenance operations in this section may be performed
with the valve in the line. Packing may be PTFE V‐ring or graphite.
An ENVIRO‐SEAL packing system is also available with the A81 valve. To install the ENVIRO‐SEAL packing system in an
existing valve, follow the instructions in the instruction manual included with the packing system (D101643X012). To
remove packing parts in a valve with the ENVIRO‐SEAL packing system, follow the procedures for valves with the
ENVIRO‐SEAL packing system in this section. Install the replacement packing following the instructions in the packing
system instruction manual (D101643X012).
Stopping Leakage
For valves with PTFE or graphite packing:
CAUTION
Tighten the packing flange only enough to prevent shaft leakage. Excessive tightening will only accelerate wear of the
packing and could produce higher torques on the valve.
Leakage around the packing followers can be stopped by tightening the packing flange nuts (key 28, figure 9).
If the packing is relatively new and tight on the shaft, and if tightening the packing flange nuts does not stop leakage,
the 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 around the packing box wall. Inspect the shaft and packing
box wall for nicks and scratches when performing the packing replacement procedures.
A81 Valve
January 2011
9
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