Abstract: The production rate, useful life and operating efficiency of electric submergible pumping systems (ESP) is improved by operating the system so that the motor (220, 320) is cooled by two passes of production. Production fluids remove waste heat from the motor (220, 320) by passing the fluid in contact with the exterior of the motor (220, 320). The improved cooling permits the motor to be operated at a lower temperature improving life and efficiency, and/or to be operated at higher power at a similar temperature. Additionally, oversized and excess equipment is not required, further improving performance and economics for the user. In another aspect, the invention is a method of pumping fluids using a motor having vortex generators (366) on its exterior surfaces or on the interior surfaces of a surrounding shroud.

Abstract: Provided in accordance with the principles of the present invention, in one preferred embodiment, is a mechanism (10). The mechanism functions in general for providing motive force, and is specially adapted for pumping applications. In particular, the mechanism includes an impeller/pumping section integral with a drive system (16). The mechanism includes a housing (14), and a tube (18) rotatably mounted within the housing. Specifically, the tube mounts in the housing for rotation of the tube relative to the housing, substantially about the tube's longitudinal axis. A power or drive system (16) connected to the tube, and/or forming part of the tube, causes the tube to rotate relative to the housing. The drive system preferably includes a plurality of magnets (42) mounted within the housing, located around the tube, for creating magnetic forces for causing the tube to rotate. One or more impellers (20) mount to the tube. The impellers are adapted to cause fluid flow through the tube when the tube rotates.