Progressive cavity assembly and associated methods

Abstract

A progressive cavity assembly can include a stator having a tubular housing and a stator section having a helical stator profile formed therein. At least one deformation of the housing secures the stator section in the housing. A method of producing a progressive cavity assembly can include providing a stator section having a stator profile formed therein, and securing the stator section in a tubular housing. The step of securing the stator section in the housing can be performed without any welding. The step of securing the stator section in the housing can include deforming the housing toward the stator section.

What is claimed is: 
     
         1 . A progressive cavity assembly, comprising:
 a stator comprising:
 a tubular housing; and 
 a stator section having a helical stator profile formed therein, 
   in which at least one deformation of the housing secures the stator section in the housing.   
     
     
         2 . The progressive cavity assembly of  claim 1 , in which each deformation of the housing extends into a recess on the stator section. 
     
     
         3 . The progressive cavity assembly of  claim 1 , further comprising a lining installed in the stator section. 
     
     
         4 . The progressive cavity assembly of  claim 3 , in which the lining comprises an elastomeric material. 
     
     
         5 . The progressive cavity assembly of  claim 1 , further comprising a plurality of the stator sections, and in which relative rotation between adjacent ends of the stator sections is prevented. 
     
     
         6 . The progressive cavity assembly of  claim 1 , further comprising a rotor configured to produce fluid flow between the rotor and the stator in response to rotation of the rotor in the stator. 
     
     
         7 . The progressive cavity assembly of  claim 6 , in which the rotor is configured to contact the stator section as the rotor rotates in the stator. 
     
     
         8 . The progressive cavity assembly of  claim 6 , in which the rotor is configured to contact a lining in the stator section as the rotor rotates in the stator. 
     
     
         9 . The progressive cavity assembly of  claim 1 , further comprising a rotor configured to rotate in the stator in response to fluid flow between the rotor and the stator. 
     
     
         10 . The progressive cavity assembly of  claim 9 , in which the rotor is configured to contact the stator section as the rotor rotates in the stator. 
     
     
         11 . The progressive cavity assembly of  claim 9 , in which the rotor is configured to contact a lining in the stator section as the rotor rotates in the stator. 
     
     
         12 . The progressive cavity assembly of  claim 1 , further comprising a plurality of the stator sections, and in which the stator sections are secured to each other without any weld. 
     
     
         13 . The progressive cavity assembly of  claim 1 , further comprising a plurality of the stator sections, and in which the stator sections are secured to the housing without any weld. 
     
     
         14 . The progressive cavity assembly of  claim 1 , in which the stator section consists of a single stator section. 
     
     
         15 . The progressive cavity assembly of  claim 1 , in which the stator section is interference fit in the outer housing. 
     
     
         16 . The progressive cavity assembly of  claim 1 , further comprising a plurality of the stator sections, the stator sections having respective different outer diameters, and
 in which multiple bores having respective different inner diameters are formed in the outer housing, the outer diameters being interference fit with the respective inner diameters.   
     
     
         17 . The progressive cavity assembly of  claim 1 , in which the stator section comprises a more wear resistant material than the outer housing. 
     
     
         18 . The progressive cavity assembly of  claim 1 , in which a wear resistant treatment is applied to the stator section. 
     
     
         19 . A method of producing a progressive cavity assembly, the method comprising:
 providing a stator section having a stator profile formed therein; and   securing the stator section in a tubular housing,   the step of securing the stator section in the housing being performed without any welding.   
     
     
         20 . The method of  claim 19 , further comprising forming the stator section comprising a non-elastomeric material. 
     
     
         21 . The method of  claim 19 , in which the providing comprises providing a plurality of the stator sections, and further comprising rotationally indexing the stator sections relative to each other. 
     
     
         22 . The method of  claim 21 , in which the rotationally indexing comprises engaging index structures on respective adjacent ends of the stator sections. 
     
     
         23 . The method of  claim 21 , in which the rotationally indexing comprises installing an alignment mandrel in the stator sections. 
     
     
         24 . The method of  claim 19 , in which the securing the stator section in the housing comprises deforming the housing toward the stator section. 
     
     
         25 . The method of  claim 19 , in which the securing the stator section in the housing comprises deforming the housing into a recess formed on the stator section. 
     
     
         26 . The method of  claim 19 , in which the securing the stator section in the housing comprises injecting a material between the housing and the stator section. 
     
     
         27 . The method of  claim 19 , in which the securing the stator section in the housing comprises interference fitting the stator section in the housing. 
     
     
         28 . The method of  claim 19 , in which the providing comprises providing a plurality of the stator sections, the stator sections having respective different outer diameters, and in which the securing comprises installing the stator sections in respective different inner diameter bores in the housing. 
     
     
         29 . The method of  claim 19 , further comprising installing a lining in the stator section. 
     
     
         30 . The method of  claim 29 , in which the installing comprises injecting a material between the stator section and an externally profiled mandrel in the stator section. 
     
     
         31 . The method of  claim 19 , in which the providing comprises heat treating the stator section prior to the securing. 
     
     
         32 . The method of  claim 19 , in which the providing comprises applying a wear resistant treatment to the stator section prior to the securing. 
     
     
         33 . The method of  claim 19 , in which the providing comprises providing a plurality of the stator sections, and in which the securing comprises securing the plurality of stator sections in the housing. 
     
     
         34 . The method of  claim 19 , in which the providing comprises providing only a single stator section, and in which the securing comprises securing only the single stator section in the housing. 
     
     
         35 . The method of  claim 19 , in which the providing comprises forming the stator section of a more wear resistant material than a material of the outer housing. 
     
     
         36 . The method of  claim 19 , in which the providing comprises forming the stator section of a less ductile material than a material of the outer housing. 
     
     
         37 . A method of producing a producing a progressive cavity assembly, the method comprising:
 providing a stator section having a stator profile formed therein; and   securing the stator section in a tubular housing,   in which the securing the stator section in the housing comprises deforming the housing toward the stator section.   
     
     
         38 . The method of  claim 37 , further comprising forming the stator section comprising a non-elastomeric material. 
     
     
         39 . The method of  claim 37 , in which the providing comprises providing a plurality of the stator sections, and further comprising rotationally indexing the stator sections relative to each other. 
     
     
         40 . The method of  claim 39 , in which the rotationally indexing comprises engaging index structures on respective adjacent ends of the stator sections. 
     
     
         41 . The method of  claim 39 , in which the rotationally indexing comprises installing an alignment mandrel in the stator sections. 
     
     
         42 . The method of  claim 37 , in which the securing the stator section in the housing is performed without any welding. 
     
     
         43 . The method of  claim 37 , in which the securing the stator section in the housing comprises deforming the housing into a recess formed on the stator section. 
     
     
         44 . The method of  claim 37 , in which the securing the stator section in the housing comprises injecting a material between the housing and the stator section. 
     
     
         45 . The method of  claim 37 , in which the securing the stator section in the housing comprises interference fitting the stator section in the housing. 
     
     
         46 . The method of  claim 37 , in which the providing comprises providing a plurality of the stator sections, the stator sections having respective different outer diameters, and in which the securing comprises installing the stator sections in respective different inner diameter bores in the housing. 
     
     
         47 . The method of  claim 37 , further comprising installing a lining in the stator section. 
     
     
         48 . The method of  claim 47 , in which the installing comprises injecting a material between the stator section and an externally profiled mandrel in the stator section. 
     
     
         49 . The method of  claim 37 , in which the providing comprises heat treating the stator section prior to the securing. 
     
     
         50 . The method of  claim 37 , in which the providing comprises applying a wear resistant treatment to the stator section prior to the securing. 
     
     
         51 . The method of  claim 37 , in which the providing comprises providing a plurality of the stator sections, and in which the securing comprises securing the plurality of stator sections in the housing. 
     
     
         52 . The method of  claim 37 , in which the providing comprises providing only a single stator section, and in which the securing comprises securing only the single stator section in the housing. 
     
     
         53 . The method of  claim 37 , in which the providing comprises forming the stator section of a more wear resistant material than a material of the outer housing. 
     
     
         54 . The method of  claim 37 , in which the providing comprises forming the stator section of a less ductile material than a material of the outer housing.