ABSTRACT
In positive displacement compressors, which are those that are used in drilling equipment, high pressure is obtained by confining the gas in a closed space, reducing the volume by moving one or various elements. The two basic features of a compressor, apart from the type or model, are: the flow of air supplied and the outgoing air pressure. When in the large drilling rigs a high pressure compressor unit is chosen, it will be possible to drill with down-the-hole hammer or with a rolling cone bit. The most commonly used in drilling are: piston compressors, when they are stationary and sliding-vane or rotary screw for the portable models either mounted on the drilling unit or towed by it. The Sliding-Vane compressors have only one rotor in cylindrical form or casting, which has longitudinal slots around its circumference that hold sliding vanes or strips.
