Submersible Pump Motor Cooling Through External Oil Circulation

摘要

An electrical submersible pump motor has motor oil flowing through external circulation tubes for cooling the motor. A substantial portion of the exterior of each tube is submerged in and exposed to wellbore fluid. Heat is transferred from the motor to the motor oil, and then circulated through the external circulation tubes to conduct heat to the wellbore fluid. Internal or external motor oil pumps may be used to propel the motor oil through the circulation tubes. Guards or baffles may be used to protect the circulation tubes and to influence the flow of production fluid over the circulation tubes.

主权项

1. An apparatus for pumping production fluid from a well, the apparatus comprising:
a submersible pump having an inlet; a motor assembly coupled to the submersible pump for submersion in the production fluid, the motor assembly having a housing with a cylindrical side wall having an exterior surface and an interior chamber containing a stator, the motor assembly having a longitudinal axis, and a volume of lubricant being located in the interior chamber; a shaft connecting the motor assembly and submersible pump, so that when the motor assembly rotates the shaft to drive the submersible pump, the production fluid enters the inlet and is pumped to the surface; a plurality of circulating tubes in fluid communication with the lubricant in the interior chamber, each of the circulating tubes extending alongside and at a distance radially outward from the cylindrical side wall of the housing; a plurality of guard structures, each of the guard structures being attached to and extending alongside an exterior surface of the cylindrical side wall of the housing; and wherein an axial length of at least one of the circulating tubes is located within, and circumscribed by, one of the guard structures.