NPR Low-pressure recirculation pump

This short horizontal propeller pump was used originally in the treatment of wastewater, where the fluid had to be conveyed from one reservoir in the treatment plant to another neighbouring one.  

The special requirements of wastewater technology led to the construction of this pump for extremely low delivery heights (up to maximum 1.5 m) and with two different installation positions. All that is needed for installation under water with a submersible motor and an automatic quick coupling is a guide rod and coupling claws on the discharge side of the flange.
 
The important point for the version to be flanged into a dry pipe, i.e. above water, is that in addition to the high level of availability, the rotor assembly remains extractable. The angular gear and propeller are therefore designed in such a way that they can be completely swivelled out of a mounted pipe connection while the pump housing remains in the straight pipe line.  

This type of pump is used typically in the tertiary treatment of wastewater as well as in plant construction and process engineering. Users in the field of plant and process engineering use this pump to boost the pressure of the pumping medium in order to compensate the losses that arise in long pipe lines due to wall friction.
 
In addition to active sludge and nitrification / denitrification, the NPR also conveys precipitation, surface and river water, pre-treated wastewater as well as industrial process water at temperatures of up to 60°C and other aqueous fluids.