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MO-D52/R52
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9/21 Rev. 0
Daily Inspection and Periodic Inspection
Daily inspection
Perform daily inspection for the control valve are important for process operation.
•
Check that air is not leaking from the instrument air pipe connecting port to prevent malfunction.
•
If a positioner is provided, check that hunting is not occurring, and the movement of the stem is
smooth.
•
Check that abnormal noise and vibration is not occurring in the control valve and the piping.
If abnormality is found in daily inspection and yet countermeasures cannot be taken immediately,
perform maintenance by disassembly when the plant can be suspended or ask KOSO’s service
representative in charge for repair.
Periodic inspection
Monthly or bimonthly inspection
Perform the following inspections for all the control valves.
•
To prevent malfunction, check that air is not leaking from the instrument air pipe connecting
port.
•
If a positioner is provided, check that hunting is not occurring, and the movement of the stem is
smooth.
•
While making adjustment, check that abnormal noise and that vibration is not occurring in the
control valve and the piping.
If abnormality is found in the inspection, and yet countermeasures cannot be taken immediately,
perform maintenance by disassembly when the plant can be suspended, or ask KOSO’s service
representative in charge for repair.
Yearly or biennial inspection and maintenance
Perform inspection, check, lubrication, replacement, etc. for the following items.
•
Lubricate the frictional section of the actuator rod and manual operation unit. Use plant approved
lubricants. The factory used lithium grease. Consult factory for additional help.
•
Check the O-rings, seal washer and dust seal (optional) for wear.
•
Check that there is no flaws such as cracks on the diaphragm.
•
Check the bolts and nuts for material loss from wear and corrosion.
•
If any defective part is found, replace it with new one.
