An introduction to compressors

Compressors are machines that compress air or gas. Compression is achieved by reducing the volume that the gas (or air) occupies. As a side effect of volume minimization, the temperature of the air or gas increases.

The higher the compression ratio, the more the temperature tends to rise. However, compressor manufacturers take this into account. The problem is solved by compressing in stages and simultaneously cooling the gas.

There are many types of compressors. Different types of compressors achieve different compression ratios. In addition, the power that the different compressors can achieve varies from 1 to 2 HP (Horsepower), up to a few thousand HP. Some compressors require oil to work, while others do not.

The most important compressor designs are listed below.

Reciprocating compressors are equipped with a crankshaft, which drives the pistons. They are commonly found in versions that produce from 5 to 30 HP. However, the larger ones used for industrial purposes can produce up to 1000 HP.

Centrifugal compressors are used for heavy industrial purposes. Centrifugal compressors produce from ~100 HP to a few thousand HP. They are usually stationary, and one of their applications is small gas turbine engines.

Rotary screw compressors are compressors intended for commercial use. Their power varies from 5 to 500 HP, and they are generally used as superchargers in automobile engines.

Mixed/diagonal flow compressors are similar to centrifugal compressors except for a few technical features.

Axial flow compressors are mainly used in large gas turbine engines.

Scroll compressors are not as efficient as rotary screw compressors. They can be found as superchargers in cars.

Along with the uses listed above, compressors are used in fields such as jet engines, refrigeration, drug manufacturing, diving, turbocharging, submarines, and air conditioning.