1, sewage nitrogen switch valve. When the four - way solenoid valve has electricity, the switch valve is closed. When the power loss is lost, the switch valve opens, and when the power is lost, the gas source can be opened by self weight when the pressure is lost. Thus, when the failure occurs, the upper tower gas can be emptied through the accumulator, and the overpressure is not caused.
2, air switch valve. When the four way solenoid valve is energized, the switch valve is opened and the switch valve is closed when the switch is out of power. When the power failure of the control power is out of power, the switching valve is closed. When the gas source fails to lose voltage, the switching valve is closed by self weight to ensure that the raw material air does not enter the air separation tower when it fails.
3, sewage nitrogen (pure nitrogen) three switch valve. Four solenoid valve power, three switch valve in the discharge position; four solenoid valve energized, three switch valve in the empty position, when the power outage, three switch valve in the empty position; when the air pressure is lost when the fault, three switch valve can lend weight in the empty position.