Pneumatic butterfly valve is usually composed of pneumatic actuator, valve body and some accessories. This paper mainly introduces the precautions for the field use of pneumatic butterfly valve.

1. The signal valve sent by the control cabinet does not act. After on-site observation, the pneumatic control butterfly valve is equipped with a solenoid valve on the premise of installing the positioner. The strong current of the solenoid valve interferes with the signal output of the control cabinet, and the valve cannot receive the signal, so it cannot work normally.

Solution: remove the solenoid valve and remove the strong electric interference from the normal operation of the equipment (Note: the function of the solenoid valve is to open and close the valve, and the function of the positioner is to control the opening of the valve with 4 to 20 mA signal, so it is unnecessary to install the solenoid valve on the premise of installing the positioner).

2. After the automatic switch to the manual state, the switch does not return to the automatic state; the internal gear is stuck due to the excessive force channel used by the on-site operator to pull the clutch too much, so it cannot be pulled back to the automatic state.

Solution: when turning the clutch, the handwheel should be rotated back and forth to release the internal turbine, so as to easily achieve the manual automatic switching (when the manual automatic switching, it is necessary to pull up the Yellow ferrule beside).

3. The valve works normally, but the feedback is always in a 100% state. Only the field wiring personnel know that the field wires are thick wires, and the hard connection is not very convenient, which causes a screw to fall. The wiring personnel directly take a long screw to tighten, so that the module is pushed by the screw, causing a short circuit.

Solution: replace the conventional screw model; it is recommended to use thin wire for connecting line.