A typical rotary screw air compressor has two interlocking helical rotors within a housing. Air will come in through a valve, typically known as the inlet valve and can be taken in to the space between your rotors. As the screws convert, they reduce the volume of the air, therefore increasing the pressure.
The center of an air compressor may be the 
screw element which can be called air-end. The air-end is the most important component of any screw-type compressor. It’s that part of the machine where in fact the actual compression takes place. It is the center of the rotary screw surroundings compressor.
A Rotary Screw Air Compressor is a compressor that uses a rotary-type positive displacement mechanism, called a rotary screw, air-end. … Rotary Screw Compressors also make use of two inter-twined helical formed screws, referred to as rotors, to compress the atmosphere.