Water screw pumps rotate in an open concrete trough and are used to lift water in sewage treatment and drainage plants.
The screw works according to the Archimedes principle and is inclined at an angle of approximately 38°. Archimedean screw pumps are suitable for pumping heavily contaminated liquids, even those containing small solid particles. The delivery head is normally only a few meters and the flow rate relatively high.
The output shaft of the gear unit, whose mounting position corresponds to the inclination angle of the screw, does not absorb any additional loads and transmits the torque to the worm shaft by means of a flexible coupling.
FLENDER gear units are specially designed to operate in these conditions. They need an adjusted oil level, a suitable shaft seal, an oil drain, and an air vent for this purpose.
Each gear unit is fitted with a backstop to prevent the screw from accelerating backwards by the water that is forced back when the motor is switched off.
Helical gear unit
2-, 3- and 4-stage
up to 10,500 kW
i = 6.3 to 450
5.8 to 1,400 kNm
Inclined position 30 to 38°
Low noise level
Integrated package solution - Mounted on a baseframe - Backstop included - Coupling protected by guard
Municipal sewage treatment plants
All applications where water has to be lifted to a higher level