Instruction Manual

Instruction Manual
D100400X012
EWN and EW-1 Valves
July 2014
5
WARNING
Personal injury could result from packing leakage. Valve packing was tightened before shipment; however, the packing
might require some readjustment to meet specific service conditions. Check with your process or safety engineer for any
additional measures that must be taken to protect against process media.
Maintenance
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 packing lubrication,
packing replacement, trim maintenance, and lapping seating surfaces. All maintenance operations may be performed
with the valve body in the line.
WARNING
Avoid personal injury or damage to property from sudden r elease of pressure or uncontrolled process fluid. Before starting
disassembly:
D Do not remove the actuator from the valve while the valve is still pressurized.
D Always wear protective gloves, clothing, and e yewear 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
from both sides of the valve. Drain the process media from both sides of the valve.
D Vent the pneumatic actuator loading pressure and r elieve 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.
Note
Whenever a gasket seal is disturbed by removing or shifting gasketed parts, a new gasket should be installed upon reassembly.
This is necessary to ensure a good gasket seal.
Packing Lubrication
CAUTION
Do not lubricate graphite packing. Graphite packing is self-lubricated. Additional lubrication may result in slip-stick
movement of the valve.