Air Compressor and Its Types

Air compressor is a device that converts power into energy stored in compressed air.

In earlier days, shops used to use one system that would give power. The power was transferred through mechanical ways. Nowadays transferring power through mechanical ways has changed and air compressors have come into existence.

Air compressors have been used for over many years now because air has been considered the safest and the most convenient. They have been the most reliable and purposeful.

These systems can generally be found in gas stations, manufacturing plants, workshops, garages etc.

However, they are available in quite a few types and sizes. The most common types of compressors used are:

  • Reciprocating or Piston Compressors
  • Rotary Screw Compressors
  • Rotary Sliding Vane Compressors
  • Centrifugal Compressors

Reciprocating or Piston Compressors
These types of 5-25 HP air compressors are positive displacement compressor and are the most common in market. They work by filling a cylindrical chamber with air by one way cylindrical valves and then reducing its volume. They are found in ranges from small fractional to high horsepowers.
Advantages

  • Simple design
  • Low initial cost
  • Easy installation
  • High efficiency

Disadvantages

  • High maintenance cost
  • Moving parts
  • Vibration problems may occur

Rotary Screw Compressors
Rotary Screw Compressors use positive displacement compression to fill the void between two helical screws with air. As and when they turn, the volume reduces thereby leading to increase in air pressure. Most of these compressors release oil for the reduction of internal leakage.

Advantages

  • Simple design
  • Low to medium initial costs
  • Low to medium maintenance costs
  • Easy installation
  • Fewer moving parts

Disadvantages

  • Lesser air-end life
  • High rotational speeds
  • Short life expectancy
  • Difficult to handle in dirty environment

Rotary Sliding Vane Compressors
Like the above, these types of compressors are also positive displacement compressors. These compressors include a rotor, stator and 8blades. As the rotor keeps turning, compression takes place as the volume increases at the intake ports and reduces at the exhaust ports. After the cycle is complete, oil and air need to be separated before air can be transferred to the system.

Advantages

  • Simple design
  • Easy installation
  • Low to medium installation costs
  • Lower maintenance costs
  • Few moving parts
  • Low rotation speed

Disadvantages

  • Difficulty with high pressure
  • Low efficiency with single stage designs
  • No oil-free design available

Centrifugal Compressors
These types of compressors, unlike Reciprocating, Screw or Vane Compressors are not positive displacement. Such compressors use high speed spinning impellers to accelerate the air then diffuser to decelerate the air. This is known as dynamic compression. However, there are several types of impeller or diffuser combinations.

Advantages

  • Can handle high pressure
  • Renders lubricant free air
  • First cost increases as cost increases

Disadvantages

  • High initial cost
  • Complicated control panel
  • Specialized maintenance costs

If you have any queries or wish to purchase a compressor, seek advice from Eaton Compressors, you can contact them on their website: www.eatoncompressor.com