DOWNHOLE MOTOR BIT SHAFT Russian patent published in 2002 - IPC

FIELD: well drilling with use of downhole motor. SUBSTANCE: downhole motor bit body accommodates stator members of rubber-metal radial supports fixed with the help of pin and connecting sub, stator races of axial rolling bearing, stator stages of rubber-metal seals of axial bearing casing, connector with holes communicating cavity of downhole motor bit shaft body with space behind said body, stator discs of multistage labyrinth seal of bit shaft. Secured immovably on bit shaft with the help of nut-coupling half are rotor bushings of radial bearings, rotors races of axial bearing, rotor discs of seals of axial bearing casing, impeller of centrifugal pump, rotor discs of bit shaft labyrinth seal. Centrifugal pump impeller is located in connector internal cavity. Connector is located between stator stages of end rubber-metal seals of axial bearing casing and stator discs of multistage labyrinth seal. EFFECT: higher operating reliability and increased service life. 3 cl, 5 dwg