Types of Compressor – A Complete Breakdown

Types of Compressor – A Complete Breakdown

There are many different compressor technologies out there and the type that you choose will be completely dependent on your application requirements. All air compressors convert energy from a motor into pressurised air that can be used as a form of energy to power many processes.

However, the way that compressors achieve compression depends on the type of technology used. The most popular method is based on the principle of positive displacement. These types of machine draw in air from an inlet at atmospheric pressure and then reduce the volume of the chamber to compress the air. Decreasing the volume increases the pressure of the air and this can then be discharged for whatever use is required.

Core positive displacement technologies include:

Rotary Screw

Perhaps the most popular type of compressor on the market, screw compressors have been relied on by many due to their durability and proven usage. No duty cycle means that this type of compressor can run continuously, without the need for downtime. Compression is created by two rotors that spin in opposite directions, trapping the air and forcing it along the rotor, thus forcing the air to a smaller volume.

Rotary Vane

Vane technology is used widely in many industries such as manufacturing, paper and pulp, woodworking, and for many other industrial tasks. The principle behind vane compression is a simple one and results in very few maintenance requirements as it has few moving parts. The air that is drawn in is contained in a chamber between eccentrically positioned rotors and the chamber wall. As with rotary screw models, the rotor turns and thus the volume decreases.


Economical and reliable, piston compressors are known for their productivity and are one of the oldest types of industrial compressor available. As the name suggests, a piston is driven in a reciprocating motion into the compression chamber, compressing the air by volume reduction.

Stationary or Portable?

When it comes to your application, you may need a compressor to be installed in your factory to be included as part of your production process or you may need a compressor for use on different sites in varying locations. Depending on your exact needs, this will decide whether you need a stationary or a portable option.

Portable compressors are ideal for construction projects where compressed air is required on-site or for installation jobs where compressors provide a means of driving electric power tools and equipment.

Oil or Oil Free?

Most of the above technologies are available as either oil lubricated or oil-free. Lubricated models are tried and tested and have long been relied on to provide high power performance on a daily basis. They are a great option for manufacturing, industrial, and other applications where sanitary operation is not required.

Oil free alternatives are a fantastic option for those in industries where hygiene is a business-critical requirement such as those in the food, beverage, brewing, pharmaceutical, and medical industries. These models do not use any oil in the compression chamber and thus there is no risk of contamination, protecting your end product.

Regulated or Variable Speed Drive?

When trying to select the most cost-effective and energy efficient compressor, you should also look at the difference between regulated and variable speed drives. Regulated speed compressors run at a fixed speed and therefore produce a fixed amount of air per minute. This is great if you have a specific, un-fluctuating demand and will be the most efficient option.

If, however, your demand fluctuates from time to time, a fixed speed compressor could be leading to wasted energy output. Variable speed drives alternate their output to meet with the demand, in this way ensuring that no energy is used when it is not required. Find out more about the benefits of variable speed compressors in our blog post.

Need help specifying a compressor?

Mid-Tech are more than just a supplier, we’re a partner. Our team of expert engineers are highly qualified and know the ins and outs of a variety of technologies, brands, and models. We can help to recommend a specific product that will meet your exact application requirements. As an authorised supplier of some of the industry’s biggest names such as CompAir, Hydrovane, Champion, and Reavell, you can be sure we have the correct product for you.

For further information on our product selection or our services such as design and installation, servicing and repairs, and preventative maintenance, please call us on 0800 028 8366 or click here to fill out our online contact form. 

Knowledge Hub