Patent ID: 9046090
Filing Date: 2015-06-02
Classification: F04B,F04D

Abstract:
1. An electric submersible pump (ESP) assembly comprising: a pump having a plurality of stages, each stage comprising a rotatable impeller and a non-rotating diffuser; a motor operatively coupled to the pump for rotating the impellers; wherein each of the impellers comprises: a plurality of curved vanes interposed between an upper shroud and a lower shroud, each of the vanes curving radially outward from an area proximate to a cylindrical hub to an outer diameter of the lower shroud; a plurality of parallel, spaced apart grooves formed in a convex surface of each of the vanes, each of the grooves extending substantially parallel with an elongate direction of the respective vane; the plurality of parallel grooves comprising an upper groove and a lower groove, wherein each respective groove of the plurality of grooves defines a pair of ridges, one formed on the upper side of the respective groove and the other formed on the lower side of the respective groove; and wherein the ridge on the upper side of the upper groove extends from the upper shroud, and the ridge on the lower side of the lower groove extends from the lower shroud.