Composite material progressing cavity stators

A replaceable progressing cavity insert for a stator, the replaceable insert comprising:

• a fiber reinforced composite component providing an internal helical cavity, the fiber reinforced composite component having an internal surface, the internal surface having at least one helical groove provided thereon;
• an elastomeric liner disposed on the internal surface of the fiber reinforced composite component;
• and
• the insert having an outer surface, the outer surface sized and shaped for removable receipt within a cylindrical tube.

A progressing cavity stator comprising:

• a substantially cylindrical tool body having a cylindrical axis and two ends;
• a fiber reinforced composite component disposed in the tool body substantially coaxially with the cylindrical axis, the fiber reinforced composite component providing an internal helical cavity, the fiber reinforced composite component having an internal surface, the internal surface having at least one helical groove provided thereon;
• an elastomeric liner disposed on the internal surface;
• and
• the elastomeric liner having a non-uniform thickness, the non-uniform thickness varying in directions of at least one of parallel to the cylindrical axis and radially about the cylindrical axis.

A progressing cavity stator comprising:

• a fiber reinforced composite component having a cylindrical axis, the fiber reinforced composite component providing an internal helical cavity, the fiber reinforced composite component having an internal surface, the internal surface having at least one helical groove provided thereon;
• an elastomeric liner disposed on the internal surface;
• and
• the fiber reinforced composite component including a plurality of fibers disposed in a matrix material, the plurality of fibers disposed such that distinct portions thereof follow correspondingly distinct directions.

A progressing cavity stator, wherein the progressing cavity stator is a product of the process comprising:

• (a) providing a first core having at least one helical groove on an outer surface thereof;
• (b) disposing a plurality of fibers in each helical groove to form a fiber preform;
• (c) inserting the fiber preform into a cylindrical tube;
• (d) injecting a resin into the cylindrical tube to form an impregnated fiber preform;
• (e) removing the first core from the impregnated fiber preform thereby forming an internal helical cavity in the impregnated fiber preform;
• (f) inserting a second core having at least one helical groove on an outer surface thereof into the internal helical cavity of the impregnated fiber preform, the second core having a smaller diameter than that of the first core, thereby forming a substantially helical annulus between the second core and the impregnated fiber preform;
• (g) injecting an elastomeric material into the helical annulus;
• and
• (h) removing the second core.

A downhole drilling motor comprising:

• a progressing cavity stator including:
• a substantially cylindrical tool body having a cylindrical axis;
• a fiber reinforced composite component disposed in the tool body substantially coaxially with the cylindrical axis, the fiber reinforced composite component providing an internal helical cavity, the fiber reinforced composite component having an internal surface having at least one helical groove provided therein;
• an elastomeric liner disposed on the internal surface of the fiber composite component;
• the fiber reinforced composite component including a plurality of fibers disposed in a matrix material, the plurality of fibers being disposed such that distinct portions thereof follow correspondingly distinct directions;
• and
• a helical rotor operational within the internal helical cavity of the progressing cavity stator;