How to choose the right compressor?

It can be very confusing to figure out which compressor that matches your needs. With this guide, we will help you to clarify your needs and thereby make it easier to find the right compressor.

The four basic elements

It is crucial that you get a solution that matches your needs. An undersized compressor can quickly become an annoyance, while an oversized compressor will not be profitable in the long run.
To be able to choose an air compressor, four basic elements should be considered.

1. What is the needed air flow?

The required amount of compressed air can be found by looking at which tools/machines that will be connected to the compressor.

2. Which working pressure?

The compressor must be aligned to the connections that require the highest working pressure.

To compensate for pressure drops in the installation, the compressor must produce a higher pressure than the connections require.

An example could be that an air tool requires a working pressure of 6 bar. The compressor must produce a slightly higher pressure here, for example 7 bar.

The working pressure depends on the specific application and therefore you should consult your dealer before purchase.

Examples of working pressures:

•  2-4 bar: Spray painting
•  6-7 bar: Pneumatics, cylinders, blowing
•  7-8 bar: Various machine tools
•  11-13 bar: Vulcanizers

Spray painting

3. How is the operating cycle?

Is the consumption of compressed air constant, around the clock, or does the consumption vary during the working day? Is there any special equipment that requires a large, periodic amount of compressed air? These questions can help uncover the operating cycle.

The operating cycle reflects how the compressed air is consumed in relation to the change of work and degree of use. 

Work shifts can be 1-, 2- or 3-team shifts per day. The degree of use (0-100%) reflects how much the compressor is used and in what intervals the air is consumed.

If there are special requirements for the duty cycle the size of the tank should support them.

Recommended load rates

  Piston compressor
Semi-professional
Piston compressor
Professional
Piston compressor
Industry
Screw compressor
Tank mounted
Screw compressor
Heavy industry
Load rate 10-20% 40-50% 50-60% 80-100% 90-100%
Dimensioning of the installation 5-10 x needs 2.0-2.5 x needs 1.7-2.0 x needs 1.1-1.3 x needs 1.0-1.1 x needs
Max. production per day (recommended) 1 hour 4-6 hours (1 work shift) 6-8 hours (2 work shift) 16-20 hours 24 hours


 

4. What air quality is required?

Depending on what the compressed air is used for, there may be specific requirements for the air quality. The compressed air quality reflects special requirements for e.g. water and oil content, particles, sterility and odour/taste. 

If there are special requirements for air quality, a more detailed analysis is necessary, which we are happy to assist with.

 

Other considerations

In addition to the above, you should also consider the following:

•  Power conditions connection requirements 
•  Ventilation to and from the compressor
•  Noise and odour nuisance
•  Availability in relation to service and maintenance

 

Read more about screw compressors here