Low-side intakes for downhole pumps, and related apparatuses and methods

Abstract

A multi-stage intake for a downhole rotary pump. A radial passageway in an inlet coupler to mitigate erosion within a cavity that is formed between the inlet coupler and an adjacent face of an impeller intermediate or outer shroud. Related apparatuses and methods are discussed.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
         1 . A multi-stage intake of a downhole rotary pump, with two or more intake stages arranged in parallel to define an inner common flowpath, and with one or more of the intake stages having:
 an outer housing defining one or more outer inlet openings;   an inlet coupler defining one or more inner inlet openings; and   one or more impellers connected to the inlet coupler, with a cavity defined at a junction between the inlet coupler and the impeller;   wherein the inlet coupler defines one or more radial passageways within the cavity.   
     
     
         2 . The multi-stage intake of  claim 1  in which:
 the inlet coupler comprises an outer ring and a shroud; 
 the outer ring is located radially outward of the shroud; and 
 the one or more inlet openings form an array of axial passageways between the outer ring and the shroud. 
 
     
     
         3 . The multi-stage intake of  claim 2  in which the shroud defines the inner common flowpath. 
     
     
         4 . The multi-stage intake of  claim 2  in which the outer ring defines a diffuser-mounting peripheral shoulder at an impeller end of the inlet coupler. 
     
     
         5 . The multi-stage intake of  claim 4  in which the one or more radial passageways comprise one or more radial apertures through the outer ring of the inlet coupler. 
     
     
         6 . The multi-stage intake of  claim 5  in which the one or more radial apertures extend through the outer ring of the inlet coupler between the impeller end and the peripheral diffuser-mounting shoulder. 
     
     
         7 . The multi-stage intake of  claim 2  in which the one or more radial passageways comprise one or more radial slots or grooves in the outer ring of the inlet coupler. 
     
     
         8 . The multi-stage intake of  claim 7  in which the one or more radial passageways intersect a downstream face of the outer ring at the impeller end of the intake coupler. 
     
     
         9 . The multi-stage intake of  claim 8  in which the outer ring forms an array of teeth that are spaced apart from one another at the impeller end to define an array of the radial passageways therebetween. 
     
     
         10 . The multi-stage intake of  claim 8  in which the one or more radial passageways are tapered with varying axial depth from the downstream face of the outer ring. 
     
     
         11 . The multi-stage intake of  claim 10  in which the one or more radial passageways are tapered with varying axial depth from the downstream face about a circumferential path. 
     
     
         12 . The multi-stage intake of  claim 8  in which the one or more radial passageways are each tapered with varying axial depth from the downstream face about a radial path. 
     
     
         13 . The multi-stage intake of  claim 1  in which the inlet coupler is located in a downhole direction of the impeller. 
     
     
         14 . The multi-stage intake of  claim 1  in which the inlet coupler is located in an uphole direction of the impeller. 
     
     
         15 . The multi-stage intake of  claim 1  defining an eccentrically weighted component that is configured to rotate within the wellbore to align a low side inlet opening defined by the eccentrically weighted component toward a low-side of the wellbore. 
     
     
         16 . The multi-stage intake of  claim 1  in which the cavity has an average axial depth of 0.001″ to 0.5″. 
     
     
         17 . The multi-stage intake of  claim 1  in which the one or more radial passageways have an average axial depth of 0.01″ to 0.5″. 
     
     
         18 . The multi-stage intake of  claim 1  in which the one or more radial passageways have a cumulative circumferential length of between 0.1% and 95% of a circumference of the inlet coupler. 
     
     
         19 . The multi-stage intake of  claim 1  having between 1 and 100 radial passageways. 
     
     
         20 . The multi-stage intake of  claim 1  in which:
 each impeller comprises an intermediate shroud that divides an outer flowpath from an inner flowpath; 
 the inner flowpath connects to the inner common flowpath; 
 an inner cavity is formed at a junction between the intermediate shroud, of the impeller, with the inlet coupler shroud; and 
 the inlet coupler comprises one or more radial passageways that connect the inner common flowpath with the inner cavity. 
 
     
     
         21 . A downhole apparatus comprising:
 a tubing string;   a downhole rotary pump; and   the multi-stage intake of  claim 1 .   
     
     
         22 . A method comprising operating the downhole rotary pump of the downhole apparatus of  claim 21  to pump wellbore fluids through the multi-stage intake, through the downhole rotary pump, and up to surface. 
     
     
         23 . A method comprising:
 rotating an impeller of a multi-stage intake to draw wellbore fluids through an inlet coupler, through the impeller, and into a downhole rotary pump, in which:
 a cavity is defined at a junction between the inlet coupler and the impeller; and 
 the inlet coupler defines one or more radial passageways within the cavity.