Air Compressor Working Principles

Through the air compressor, the air is compressed by absorbing, pressuring the atmospheric air in reduced volume. An air compressor is a popularized device to supply compressed air or power into a specific field. It is a vital mechanical device applied in the homeowners like refrigerators and air conditioners, jet engines, commercial businesses, refining industries, manufacturing industries and automotive industries. The air compressor has already been used in the industries for more than 100 years.

Three Main Types
The air compressor varies in types and it is designed to fulfill the demands of users. Every type differs in the cooling method, compression stage, lubrication, power source, etc. There are three major types of air compressor at below.
1. Reciprocating or piston air compressor
A reciprocating air compressor uses piston to compress air and put it in a storage tank. Based on compression stage quantity, the reciprocating compressor is divided into a single-stage or double stage configuration. As for the single-stage type, only one piston works, yet there are two pistons for air compression in the double stage type
2. Rotary air compressor
Similar to the reciprocating compressor, the rotary air compressor also owns the positive displacement configuration. There are two spinning helical screws or rotors for compressing air instead of using pistons. When the screws mesh towards each other, the air will be compressed and pushed into a storage tank.
3. Centrifugal air compressor
The centrifugal air compressor, also called dynamic compressor is applicable to meet high demand for compressed air. Through the high speed rotating impeller, the velocity of air is increased and converted by the diffuser into pressure. The centrifugal air compressor needs more energy for operation than the other two types.

Working Mechanism
The air compressor owns two major parts including the compressing system and the power source. Different types of air compressors have various compressing devices, like piston, rotating impeller or vane. The power usually comes from the electric motor or other energy sources. The compressing device performs in compressing atmospheric air with the energy from the power source.

In the working process, the atmospheric air is drawn through the intake valve in a limited space mechanically by means of piston, impeller or vane. As the amount of pulled atmospheric air increases in storage tank, the volume is reduced and the pressure is raised automatically. Then the free or atmospheric air is compressed.

The air compressor is configured with a pressure setting knob that can be controlled according to the demands of operators. As the pressure in the tank increases to the maximum level, the pressure switch will be shut off to stop the intake of air in the compressor. In the contrast, the pressure inside the compressor will decline when the compressed air is discharged. Then the pressure drops to a low setting and the pressure switch is turned on to let atmospheric air enter the machine. In this way, the cycle of air absorbing and compressed air discharging continues in the air compressor.

If planning to purchase a used air compressor, users have to check the performance, machine configuration, operation type, price and operating cost of the unit before closing the deal.