Compressors are mechanical devices used to increase the pressure of gas or vapor to be transferred from one point to another through a pipe.
They can be found in our homes or workplace and are used in many fields like refrigeration, engines, chemical processes, gas transmission and manufacturing and in just every place that there is a need to move or compress gas.
Types of compressors:
Compressors can be classified in several categories by:
1. The design and principle of operation:
• Reciprocating compressor
• Rotary screw compressor
• Turbo Compressor
2. The number of stages:
• Single stage compressor
• Two stage compressor
• Multi stage compressor
3. The pressure limits:
• Low pressure compressors
• Medium pressure compressors
• High pressure compressors
• Super high pressure compressors
4. The capacity:
• Low capacity compressors
• Medium capacity compressors
• High capacity compressors
5. The method of cooling:
• Air cooled compressor
• Water cooled compressor
But the main classification is based on compression mode: intermittent and continuous.
The intermittent mode of compression is cyclic in nature and the continuous mode is one in which the gas is moved in to the compressor and discharged without interruption of flow at any point in the process.
Positive displacement compressors using intermittent compression mode are divided to two different types:
a. Reciprocating compressors
b. Rotary compressors
Continuous compressors are also characterized by two fundamental types:
The below chart show the ranges that each compressor can work well:
You can see different types of compressors in following chart:
Drivers are devices that give compressors the energy to compress the gas. Drivers must supply torque of a specified value at a certain speed.
Electrical motors or mechanical motors like internal combustion engines or steam and process gas used in turbines or expanders can be used as driver.
1. Compressors selection and sizing by Royce N. Brown, second edition 1997
2. Compressor handbook, Paul C. Hanlon