Abstract: A method of limiting core deflection in the manufacture of relatively long sections of progressing cavity pump production tubing wherein a core is held within the bore of a length of tubular casing to provide a form for the molding of a stator element. The core is centered and stabilized within the tubular casing at selected intervals prior to the injection of elastomeric material by one or more core centering bearings. The bearings are effective to prevent core deflection during manufacture and, rather than being removed after curing of the stator, are left in the casing to function as rotor bearings for the progressing cavity pump. The bearings, themselves encapsulated by elastomeric material during the manufacturing process, help maintain the rotor in optimal alignment within the production tubing thereby benefitting pump performance and longevity.

Abstract: A stator assembly is provided for use in a progressing cavity pump. The assembly includes a tubular pump barrel in which are slidably positioned a plurality of cup-like spacers. Each spacer has a tubular wall, an inlet end with an internal annular flange and an outlet end defined by a circumferential edge of the tubular wall. An elastomeric stator segment is housed in each spacer. Each stator segment has adjacent an outlet end thereof a circumferential external lip portion and has a contoured cavity therethrough generally coaxial with the pump barrel and adaptable to rotatably receive a progressing cavity pump rotor therein. The lip portion of each stator segment is captured between a spacer outlet end circumferential edge and the next adjacent spacer annular flange portion so that the elastomeric stator segments are retained in serial position within the pump barrel by the spacers permitting the spacers and stator segments to be easily removed from the pump barrel for repair and replacement.