As an essential part of industry, reciprocating compressors are used for transmission of a variety of compressed gasses. They are the most common type of compressor used for air and refrigerant compression. Primarily, this type of compressor is found where high compression ratios are required without high flow rates, and the process fluid is fairly dry. They are extremely energy efficient, and have a low failure rate. However they fail to succeed in low pressure or deep vacuum situations.
A reciprocating compressor is so called due to having one or more pistons inside one or more cylinders, and a crankshaft to drive the pistons up and down, or side to side, hence reciprocating. While many configurations are available, the most common are horizontal, vertical, tandem and horizontal balance opposed. The crankshaft is driven by a motor of either electric, petrol or diesel or similar. The movement of the pistons increases the pressure of the air by reducing its volume, thus reciprocating compressors are positive displacement machines. Notably, due to the nature of the reciprocating compressor, the output is a pulsating one.
This type of compressor can either be single acting if compression is achieved on only one side of the piston, or double acting if compression is achieved on both sides of the piston. Obviously heat is produced with the action of the reciprocating compressor, and there is a choice of water or air cooled configurations.
Reciprocating compressors are utilised throughout industry and play a central, critical role in production facilities. They are found in the vast oil refineries where they pump crude oil from one processing unit to the next. Industrial gas facilities use reciprocating compressors to transport gas through pipelines across the country. Refrigeration industries use them to transport the refrigerant and they are found extensively in chemical plants. Reciprocating compressors are also used to blow the plastic bottles made of polyethylene terephthalate (PET) for our everyday needs.
By far the most common type of compressor, the reciprocating compressor can be found as a workhorse in many a home workshop. The basic ones are cheap to buy and easy to maintain and are ideal for simple occasional use.