Screw Compressor

As the name suggests, rotary screw compressors use rotary movements to compress the air.  Within the compressor, there is a set of male and female rotors. They will be designed differently so that, when turned in unison, air will become trapped between them. The male rotor has convex lobes and the female rotor has concave cavities; in this way, they can mesh together without touching to achieve compression. Additionally, the male rotor will have slightly less lobes than the female, meaning it will rotate more quickly, effectively driving the female rotor.