DOWNHOLE ELECTRIC SUBMERSIBLE PUMPS WITH HIGH ROTORDYNAMIC STABILITY MARGIN

摘要

An electric submersible pump is provided which has improved vibrational characteristics relative to conventional electric submersible pumps. The improved electric submersible pumps comprise an electric motor mechanically coupled to a pumping section. The improved vibrational characteristics of the electric submersible pump are attributed to the presence of one or more rotor bearings selected from the group consisting of herringbone patterned rotor bearings, pressure dam rotor bearings, circumferential groove rotor bearings, and combinations of two or more of any of the foregoing rotor bearings.

主权项

1. An electric submersible pump comprising:
(a) an electric motor comprising a at least one stator, at least one rotor, and at least one rotor bearing, said electric motor being configured to accommodate a lubricant, said electric motor being configured such that during operation of the electric submersible pump the lubricant is in fluid contact with one or more rotating surfaces of the rotor bearing and the rotor; (b) a pumping section comprising a plurality of impeller vanes; and (c) a drive shaft mechanically coupled to the rotor and the impeller vanes; wherein at least one at least one rotor bearing is selected from the group consisting of herringbone patterned rotor bearings, pressure dam rotor bearings, and circumferential groove rotor bearings.