Overview
An air compressor is a machine that takes ambient air from the surroundings and discharges it at a higher pressure. It is an application of a gas compressor and a pneumatic device that converts mechanical power (from an electric motor, diesel or gasoline engine, etc.) into potential energy stored in compressed air, which has many uses. A common application is to compress air into a storage tank, for immediate or later use. When the delivery pressure reaches its set upper limit, the compressor is shut off, or the excess air is released through an overpressure valve. The compressed air is stored in the tank until it is needed. The pressure energy provided by the compressed air can be used for a variety of applications such as pneumatic tools as it is released. When tank pressure reaches its lower limit, the air compressor turns on again and re-pressurizes the tank.
A compressor is different from a pump because it works on a gas, while pumps work on a liquid.
Classification
Compressors may be classified according to the pressure delivered:
Low-pressure air compressors, which have a discharge pressure of or less
Medium-pressure compressors which have a discharge pressure of
High-pressure air compressors, which have a discharge pressure above
There are numerous methods of air compression, divided into either positive-displacement or roto-dynamic types.
Single-stage reciprocating compressor
Multi-stage reciprocating compressor
Compound compressor
Single stage rotary-screw compressor
Two-stage rotary screw compressor
Rotary vane pump
Scroll compressor
Centrifugal (roto-dynamic or turbo) compressor
Axial compressor, often used in jet engines.
From Wikipedia (CC BY-SA 4.0).