The reciprocating, or piston compressor, is a positive displacement compressor that uses the movement of a piston within a cylinder to move gas from one pressure level to another (higher) pressure level. The simplest example of this is the bicycle pump used to inflate a bicycle tire.

In the bicycle pump example we have the piston attached to a long rod, a pump cylinder (a tube or pipe closed on each end), two ball-type check valves (one inlet and one outlet), a flex hose and a connection device. The piston is as simple as a leather or rubber disk with two smaller diameter metal disks on either side to give the piston strength and stiffness.
The cylinder is the tube that the leather-sandwiched piston moves within. The inlet or suction spring-loaded ball valves allow ambient air to flow into the cylinder as the piston is partially withdrawn from the cylinder (creating a partial vacuum) and closes while the piston compresses the air within the cylinder on the compression stroke; while the discharge ball valve (which is closed on the suction cycle) opens to let the compressed air flow out of the cylinder and into the receiver or tire.

Reciprocating compressors are used in many different industries:

• Oil & gas
  • Oil refineries
  • Gas gathering
  • Gas processing
• Transportation
  • Gas pipelines
• Chemical plants
• Refrigeration plants (large and small)

Reciprocating compressors types include the:

— Single-cylinder compressor
— Multi-cylinder balanced opposed compressor, and the
— Integral-engine compressor.