Magnetic Coupling Unit for Submersible Well Pumps

摘要

An electrical submersible well pump assembly includes a rotary pump and a motor. An inner rotor is coupled to the motor shaft. The inner rotor has steel discs stacked together with end caps at each end. The discs have apertures that align to define axially extending slots. Each of the slots has a closed outer wall spaced radially inward from an outer diameter surface of the inner rotor. Inner rotor magnets are located within the slots. Continuous open and thin gaps between rotating components act as hydrodynamic bearings. Damper bars extend axially at points between the outer walls of the slots and the outer diameter surface of the inner rotor. An outer rotor has a bore that receives the inner rotor, the outer rotor being operatively coupled to the pump shaft for rotation therewith. Outer rotor magnets are mounted to the bore of outer rotor.

主权项

1. An electrical submersible well pump assembly, comprising:
a rotary pump having a rotatable pump shaft; a motor having a motor shaft that is rotated by the motor and extends along an axis of the pump assembly; a magnetic coupling unit, comprising: an inner rotor operatively coupled to one of the shafts for rotation therewith, the inner rotor having a plurality of slots therein, each of the slots having an outer wall spaced radially inward from an outer diameter surface of the inner rotor; a plurality of inner rotor magnets, each located within one of the slots; an outer rotor surrounding the inner rotor and operatively coupled to the other of the shafts for rotation therewith; and a plurality of outer rotor magnets mounted to the outer rotor to attract the magnetic fields of the inner rotor magnets and cause the inner and outer rotors to rotate in unison.