Both a Gardner Denver reciprocating compressor and a Gardner Denver reciprocating pump use the operating principle of reciprocating technology. This technology is a piston moving forward in a cylinder via a connecting rod and crankshaft. If only one side of the piston is used for compression, it is described as single acting. If both sides of the piston, top and underside are employed, it is double acting. The versatility of the piston compressors knows virtually no limits. It compresses both air and gases with very little alterations and is the only design capable of compressing air and gas to high pressures.
The configuration of a piston compressor can be a single cylinder for low pressure/low volume to a multi-stage configuration capable of compressing to very high pressure. In these compressors, air is compressed in stages, increasing the pressure before entering into the next stage to compress the air into even higher pressure.