Abstract: Pump for pumping liquids, especially oil, from deep wells comprising a screw pump which is driven by a submersible motor and welding a driving spindle to which several, preferably three screw-shaped rotors, are assigned, and further being constructed as a sealing spindle, hydraulic support bearings for intercepting the axial thrust, and inlet openings which are protected against wear particles by a screen disposed on the screw-shaped rotors on the suction side and connected over bypass pipelines with the pressure side.

Abstract: In a displacement pump having at least one screw spindle which is mounted in an opening in a housing surrounding same between a suction chamber and a pressure chamber, the profile termination of the spindle, at the pressure end, is turned off in a conical configuration at the outside diameter (d), and the angle of inclination (w) of the conical surface (43) is below 10.degree.. In addition the spindle is to be provided at its end on the suction side with a conical surface with an angle of inclination (w.sub.1) which is below 5.degree., preferably below 3.degree..