Definition: As a physical variable of state, pressure indicates the result of a force acting on a surface. The general unit of measure is Pascal (Pa), but bar is also used frequently, particularly for fluids. Various pressures are relevant in the practical application of fluid conveyance.
  • Resting pressure: the static pressure when no medium is flowing.
  • Flow pressure: the dynamic pressure when a medium is flowing.
  • Delivery pressure (also: delivery head): the pressure that is transferred from the pump to the medium.
  • Differential pressure: the pressure created by a pump for a fluid handled to overcome the given resistances of an installation.
  • Operating pressure: the pressure that exists in the installation during operation.
  • Pump pressure: the pressure created by the pump on the pressure side during operation.
On top of that, the permissible operating pressure of the pump (and other components of the installation) is also important for the safe operation of the installation. It is defined by the pump manufacturer to ensure the safety of the transporting unit. If pressure losses occur during the operation of an installation, it indicates an inefficient operation. Causes could be wall friction in pipe systems or flow resistances in valves. Avoiding pressure losses increases the overall efficiency of the installation. The correct dimensioning of pumps supports the overall efficiency – and help comes in the form of the PUMPselector.                                   Overview of pressure components with an assumed zero-loss flow