Patent ID: 6907925
Filing Date: 2005-06-21
Classification: E21B,F04C

Abstract:
1. A moineau pump assembly, comprising: a stator; a rotor extending through the stator, the rotor and stator sealingly engaging each other at spaced intervals to form a series of annular spaces; an upstream primary inlet for fluids to enter a first of the series of annular spaces; a drive unit rotating the rotor such that, as the rotor rotates, fluids are drawn through the upstream primary inlet and the series of annular spaces between the rotor and the stator; a portion of the rotor comprising a central flow passage extending from a downstream secondary inlet spaced downstream from the upstream primary inlet to the upstream primary inlet; and a flow diversion unit for diverting a portion of the fluids being pumped into the downstream secondary inlet such that said fluids pass under pressure through the central flow passage of the rotor to the upstream primary inlet and wash accumulated solids from the upstream primary inlet.