Shanghai Royal Machinery Co.,Ltd

Oil Free Screw compressor system working principle

2, Load: In about 5 – 10s after the primary motor is converted into delta-mode running, the controller makes the loading solenoid valve electrified and opened, the exhaust valve is closed, the air-incoming valve is opened and the main engine starts loaded running. When the pressure inside of the water-air bucket is over 0.4MPa, the minimum pressure valve is opened and the compressor starts air supply outwards. 

3, Unload - load: When detecting the system pressure up to the unloading one, the controller makes the loading solenoid valve power-off and, at this time, the air-incoming valve is closed and the exhaust valve is opened and, when the outside atmospheric pressure is heavier than that of the water-air bucket, the minimum pressure valve is closed. The compressor continues running, sucks air via the pores on the air-incoming valve and compresses it into the said bucket. The exhaust valve is opened to get exhausted to make the pressure inside of the said bucket kept at 0.4MPa so as to have the system maintained at normal running. The primary motor is then at idle running and the current comes as about 15% of the full load. When the outside air supply pressure lowers to the loading one, the controller makes the loading solenoid valve electrified, the exhaust valve is closed, the air-incoming valve is opened and the compressor runs with load to start air supply outward, circularly acting in this way。