Patent ID: 6099271
Filing Date: 2000-08-08
Classification: F04D,F16C

Abstract:
An electrical submersible pump assembly for use in a well, comprising in combination:an electrical motor having a lubricant-filled housing, a rotor and a stator;a centrifugal pump having a plurality of pump stages within a housing;a seal section connected between the pump and the motor for sealing well fluid from the motor and for reducing a pressure differential between the lubricant in the motor and the fluid in the wellbore;a shaft extending through the motor, seal section and pump for driving the pump; anda plurality of bearings in the motor, seal section and pump for stabilizing the shaft, at least one of the bearings in the motor being immersed in the lubricant in the motor and having bearing surfaces comprising a plurality of lobes mounted symmetrically about the shaft, each of the lobes being a curved surface that faces the shaft, and having center of curvature offset from a center of said shaft.