Air compressors have many applications in industries and they are used in different fields, including assembly and automation, agriculture, chemical manufacturing and construction. All air compressors operate by converting power from external sources, like diesel engines or electric motor into stored energy which can then be released in the form of pressurised air. That pressurised air is then used to power machinery and tools.

Choosing the Right Device

However compressors usually vary in their air capacity, method of operation and level of pressure which can be delivered. The right device will able to hold adequate air and deliver the required level of pressure for the job, but its performance should be balanced against other considerations such as durability and cost. The compressed air is normally measured in CFM (cubic feet per minute), with a higher requirement for CFM requiring a larger air capacity and HP (higher horsepower).

Types of Industrial Air Compressor

There are 3 major types of industrial air compressor and they are based on their method of operation. These are centrifugal, rotary screw and reciprocating compressors.

Reciprocating

The reciprocating ones are positive displacement devices, where the air is reduced in volume to increase the pressure. Reciprocating has pumps which are run by pistons with cylinder compressing and displacing air. There are 2 types, belt drive type and direct drive type. The belt drive type is more durable and can produce higher pressures. Reciprocating types are available in multi stage and single stage. The multi stage type delivers higher pressures and is more efficient, this means lower energy consumption and lower expenses. Reciprocating type is normally portable and appropriate for those people who are involved in construction and related fields.

Rotary Screw

Rotary screw air compressor also operates by a positive displacement process. It utilises 2 helical screws which are meshed together to force the air through and then compress it. The process of operation is easier as compared to that of pistons, with less vibration and surges than that at times found in reciprocating types. They are easy to maintain and durable. Rotary screw type generally has a greater capacity as compared to reciprocating type and can produce higher air pressures. Some types have adjustable speed drives and this means that pressure and airflow can be controlled, and when airflow needs are variable it can result in substantial energy savings. Rotary screw type has numerous applications, and is used in areas such as hospitals, construction sites and factories.

Centrifugal

Centrifugal type works by a different mechanism. It utilises the momentum which is gained from a rotating disk to transmit and pressurise air. The process is referred to as dynamic displacement and is normally a continuous process, leading to a steady supply of pressurised air. This type can produce very high pressures. However the process also requires higher air capacities and higher speeds than other compressors. Centrifugal compressors have numerous applications, and are used for machinery like pneumatic drills, turbochargers and automotive superchargers, as well as for refrigeration and air conditioning.