Installation, Operation and Maintenance Manual
H-A003-E-15 Ball Valve Type 21・21α Pneumatic Actuated Type AA 29
(21) Inspection items
- Perform periodic maintenance. (Leakage may develop due to temperature changes or over periods of
prolonged storage, rest or operation.)
○Periodically inspect and maintain the AV valve in accordance with the decided schedule.
Portion to be inspected Inspection item
1) Existence of rust, peeling of paint, and dirt of inspection hole of valve
2) Tightening condition of respective threaded portions. (Loose or not)
3) Existence of rust and corrosion around the limit switch, and existence of
4) Existence of abnormality in opening and closing operating sounds.
* It is unnecessary to supply oil to this actuator.
Va l v e
1) Existence of scratches, cracks, deformation, and discoloring.
2) Existence of leakage from the valve to the outside.
3) Existence of leakage when the valve is closed fully at right or left.
Problem Cause Treatment
The handle is not (can’t be)
turned when the valve is
The valve has already been opened fully. Turn the handle in the reverse
The air is supplied to actuator. Shut the main air valve, and open the
Foreign matter is in the valve. Disassemble the valve to remove
foreign matter. (Refer to page 28)
The torque of the valve is increased by the
piping stress. Remove the piping stress.
The torque is increased by the influence
(temperature, components, pressure) of fluid
on the valve.
Check service condition.
(Refer to page 6)
The valve does not operate by
The power source of the control panel is
turned off. Turn on the power source.
The solenoid valve is disconnected. Check the connection again.
(Refer to page 7, 21)
The supply voltage to the solenoid valve is
wrong. Check voltage with a tester and set
The voltage to the solenoid valve is low.
The bypass valve is opened. Close the bypass valve.
The speed controller is turned right excessively. Turn the adjuster know left.