Abstract: Pressurized lubricant is used for stabilizing shaft bearings in an electrical submersible pump motor. A lubricant pump is located within the motor housing. The lubricant pump has a set of impellers attached to a lower end of the shaft and rotating with the shaft, the impellers being located in the flow path of the lubricant. A diffuser is located upstream of and adjacent each impeller. The impellers increase the radial velocity of the lubricant, and this velocity is converted into a pressure head at the impeller outlet. The lubricant flows through the first diffuser, through the first impeller, through the second diffuser, and then flows through the second impeller and out into a reservoir. The shaft has an axial flow passage with an outlet at each bearing. The outlet has at least three ports arranged symmetrically around the shaft for discharging lubricant into a clearance between the shaft and bearing to create a fluid film.

Abstract: An electric motor has a housing with a plurality of stator discs. The discs have slots that align with one another, forming passages. A dielectric film tube inserts into the slots, each of the tubes having a continuous circumference. Each tube has a nonmeltable dielectric film layer of high temperature insulation. The dielectric film layer has overlapping edges and is bonded to a carrier layer of a meltable material. The tubes may be inserted into the slot passages by drawing a vacuum in the interior of each tube, causing it to collapse so that it can be readily inserted.