With constant power, when the rotation speed changes, the flow and pressure also change.

For example, a 22KW air compressor:

  • when the pressure is determined to be 7 bar, the airflow is 3.7 m3 / min.
  • when the pressure is determined to be 8 bar, the airflow is 3.4 m3 / min

The speed must be reduced when the air pressure is increased, otherwise, the drive motor will be overloaded, so the airflow is also reduced accordingly.

Thus, the steps for selecting an air compressor are: first, determine the working pressure, then the corresponding volume flow, and finally the power.