Patent ID: 8696334
Filing Date: 2014-04-15
Classification: F04B,F04D

Abstract:
1. A submersible pumping system for downhole use in extracting fluids containing hydrocarbons from a well, the pumping system comprising: a rotary induction motor that rotates a shaft about a longitudinal axis of rotation; a motor casing that houses the rotary induction motor such that the rotary induction motor is held in fluid isolation from the fluid being extracted; one or more pump stages attached to the shaft outside of the motor casing, the one or more pump stages being configured to impart fluid being extracted from the well with an increased pressure; and a heat transfer mechanism disposed at least partially within the motor casing that transfers heat generated by operation of the rotary induction motor out of the motor casing, wherein the heat transfer mechanism comprises a fluid pump disposed within the motor casing that is physically separate and disconnected from the shaft and powered separately from the motor, the fluid pump being configured to circulate a reservoir of internal fluid within the motor casing to form a convective thermal coupling between working components of the rotary induction motor and the motor casing, and wherein the reservoir of internal fluid is held internally within the motor casing.