ASAHI AV VALVES Installation, Operation and Maintenance Manual
Butterfly Valve Type 57, 56, 56D Electric Actuated Type S 24
(13) Inspection items
- Perform periodic maintenance. (Leakage may develop due to temperature changes or over periods of
prolonged storage, rest or operation.)
Portion to be inspected Inspection item
- Existence of rust, peeling of paint, and dirt of inspection hole of valve travel indicator.
- Tightening condition of respective threaded portions. (Loose or not)
- Existence of rust and corrosion around the limit switch, and existence of internal
- Existence of rust and corrosion of terminal board, and existence of disconnection.
- Existence of abnormality in opening and closing operating sounds.
- Smooth operation of manual handle.
* It is unnecessary to supply oil to this actuator.
Va l v e
- Existence of scratches, cracks, deformation, and discoloring.
- Existence of leakage from the valve to the outside.
- Existence of leakage when the valve is opened 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 valve is kept as it is electrified in the
direction reverse to the handle operating
Turn of the power source.
Foreign matter is in the valve. Disassemble the valve to remove
foreign matter. (Refer to page 11)
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 actuator is disconnected.
Check the connection again.
(Refer to page 9, 10)
Open and close are electrified
The actuator is connected wrongly.