Oil-injected screw air compressor

An oil-injected screw air compressor, comprising:

• a first stage compression chamber;
• an air buffering chamber coupled to the first stage compression chamber;
• a second stage compression chamber coupled to the air buffering chamber;
• an oil cooling device for cooling lubricating oil for the first stage compression chamber, the air buffering chamber and the second stage compression chamber;
• a plurality sensors respectively located at outlets of the first stage compression chamber, the air buffering chamber and the second stage compression chamber;
• and
• a control unit respectively and dynamically controlling flow rates of the lubricating oil entering into the first stage compression chamber, the air buffering chamber and the second stage compression chamber according to outlet pressure and outlet temperature data measured by the sensors, and temperature data and humidity data of an environment.