Below is a list of Screw Compressors manufacturers from Philadelphia, Pennsylvania. A screw compressor, also referred to as a rotary screw compressor, is an air compressor in which the air is compressed between two intermeshing, counter-rotating screws contained within a specially shaped chamber. As the mechanism rotates, the movement of the two rotors produces an area of air that steadily condenses in volume. As the compression of air continues, the reduced pockets of air are discharged through another area of the chamber.