Patent ID: 7628209

Claim:
An apparatus for pumping a cased well, comprising: a wellhead assembly for location at an upper end of a cased well; a string of tubing for suspension by the wellhead assembly within the well, the string of tubing having an upper portion at the wellhead assembly; a drive source at the wellhead assembly and coupled to the upper portion of the string of tubing for rotating an entire length of the string of tubing; a progressing cavity pump having a housing containing a stator and secured to a lower end of the string of tubing for rotation therewith, the housing having an open lower end for fluid communication with well fluid in the cased well and an open upper and in fluid communication with an interior of the string of tubing; a rotor located within the stator; an anchor mechanism located below the stator for gripping engagement with casing; a shaft coupled to a lower end of the rotor and extending downward through the open lower end of the housing to the anchor mechanism to prevent rotation of the rotor; and wherein the shaft has a smaller outer diameter than the open lower end of the housing, defining an annular intake port between the shaft and the open lower end of the housing for well fluid in the casing.