Variable speed air compressor system mainly consists of four systems: suction system, cooling and lubrication system, control system and exhaust system. Among them, the exhaust system consists of an oil-gas separator, a minimum pressure valve, a rear cooler, a trap and a connecting pipe. The compressed oil-gas mixture is separated by exhaust check valve into oil-gas separator. After separation, compressed air enters the rear cooler through minimum pressure valve. After cooling, water is separated by trap and finally enters the gas supply pipeline.

The working cycle of variable speed air compressor is divided into four stages: suction, sealing, compression and exhaust. With the rotation of the rotor, each pair of meshing teeth completes the same working cycle one after another.

First, inhalation process – the rotor passes through the entrance, and air is inhaled from the main engine axially.
Second, closing process – after the rotor passes through the entrance, a certain volume of air is sealed in the compressed cavity formed by the two rotors.
Third, compression and conveying – with the rotation of the rotor, the volume of the compression chamber decreases and the air pressure increases.
Forth, exhaust process – the air reaches the other end of the outlet and completes the compression.

In daily maintenance, there are five points that are often met:

First, the variable speed air compressor can not start.
Second, on-load shutdown of air compressor;
Third, the air compressor can not meet the required supply pressure;
Forth, pipeline pressure is greater than the set value of unloading pressure.
Fifth, frequent loading and unloading.

The fault analysis of the thermal control angle of air compressor is carried out, and the following conclusions are drawn:

First, faults of temperature original parts, minimum pressure damage, working condition delay of pressure regulator, overload of motor, etc.
Second, loading and unloading solenoid valves and vent valves;
Third, loading and unloading solenoid valve, pressure regulator, minimum pressure valve.