Abstract: A positioning member (11) for a tubular (10) is formed using a prefabricated fibre-reinforced resin shell (1) positioned upon a surface of the tubular and bonded to provide a protrusion upon the surface of the tubular. In a disclosed method a fibre-reinforced resin shell (1) is secured to an external surface of a tubular (10) thereby enclosing a cavity between the shell (1) and the surface of the tubular (10); a bonding agent is introduced through inlet ports (5) in a surface of the fibre- reinforced resin shell (1) to fill a cavity between the shell (1) and the surface of the tubular (10), and the bonding agent is cured.

Abstract: In one embodiment, a wear band comprises a rotating element having a bore receivable on a tubular, the bore comprising first and second bore portions slidably receiving first and second sleeve bearings. Outer surfaces of the sleeve bearings slidably engage the bore portions and the bores of the sleeve bearings slidably engage the tubular. A first stop collar and a second stop collar may be received on the tubular to together straddle the rotating element and sleeve bearings to longitudinally secure the rotating element in a position on the tubular. The tubular may be included within a tubular string run into a borehole or into the bore of an installed casing, such as in casing while drilling. The rotating element provides stand-off between a tubular and the wall of a bore, reduces frictional resistance to longitudinal sliding and also to rotation of the tubular string within the bore.

Abstract: A centralizer having a plurality of collapsible bows interconnecting a first collar and a second collar, with the centralizer disposed on a tubular with a stop collar, and an attachable retainer(s) of the centralizer blocking passage of the stop collar therethrough. The bows may have a yield strength of at least about 200,000 psi. Outer surface of the bows may have a coefficient of friction equal or less than about 0.02. Maximum radial thickness of centralizer when the plurality of collapsible bows is fully collapsed may be equal to or less than 3/16?. Centralizer may be rotatable relative to tubular. Centralizer having a split tubular body forming first and second collars connected by collapsible bows and a retainer to retain the split tubular body on the tubular, and the retainer, the first collar and/or the second collar providing a recess therein to receive a stop collar of the tubular.

Abstract: Embodiments of the disclosure provide a rigid centralizer having at least one annular band with radially extending embossed flutes spaced around an outer surface of the at least one annular band and a plurality of elongated connecting posts welded to an inner surface of the at least one annular band to form a tubular receiving annulus.

Abstract: A stop collar is assembled using a method including the steps of receiving a bore of a base having a set of fingers extending along an exterior of a tubular, receiving a bore of a sleeve onto the tubular adjacent the set of fingers, and receiving the sleeve onto the set of fingers in an interference-fit. In alternate embodiments, the base comprises a plurality of angularly distributed fingers and/or the base comprises a gap to permit conformance of the base to the tubular. A fingerless base may cooperate with one or more separate fingers to form a base. In an embodiment of the method, the sleeve may be thermally expanded prior to the step of receiving the sleeve onto the set of fingers. The sleeve may be heated to expand the bore prior to being received onto the set of fingers.

Abstract: A method of forming a centralizer where a flat plate is created into a tubular where the flat plate is typically rolled so that two sides of the plate contact one another and are then linked, typically by welding. Openings are then created in the tubular such that there are no corners or other points that stress cracks may originate. Once the openings are created the remaining material between adjacent openings forms ribs. The openings created in the tubular are generally aligned with the long axis of the tubular. The material at the upper and lower end of the flat plate where openings were not created serve as circumferential collars. The ribs may be radially outwardly expanded in order to provide adequate stand-off. In many instances the ribs will also be hardened by heat treating or other hardening processes.

Abstract: A close-tolerance expandable bow spring centralizer 8 having a first expandable collar 10A coupled to and spaced apart from a second expandable collar 10B through a plurality of bow springs 30 wherein expandable collars 10A, 10B comprise a plurality of slidably coupled links 16 that separate to expand the diameter of the collars 10A, 10B, e.g., upon expansion of an expandable pipe string 80 on which the centralizer 8 is received. Expandable bow spring centralizer 8 may grip the expandable pipe string 80 when in the collapsed configuration to eliminate the need for a stop collar. Additionally or alternatively, a fin 32 may be connected to each bow spring 30, and then connected to one or more adjacent fins 32 upon collapse of the bow springs 30 to form a restraining band 39 that may be ruptured, e.g., upon expansion of the expandable pipe string 80.

Abstract: A bow-spring centralizer (6) includes bow springs (5), moving collars (11) secured to each end of each bow spring, and interlocked stop collars (10). Extendable collars (8) may each be formed of a moving collar (11) movably interlocked with a stop collar (10). The centralizer (6) may optionally be formed from a tube cut using a laser to create two extendable collars coupled by bow springs. Each extendable collar may include heads integrally formed on extensions protruding from a collar (stop collar or moving collar). The heads may be generally rectangular, arrow, or teardrop-shaped head or some other shape. Each head may be slidably captured within a chamber on the interlocked collar (moving collar or stop collar). The extensions of each interlocked tubular member define the outer walls of the chamber in which a head of the interlocked tubular member is slidably captured.

Abstract: A method of and apparatus for deploying a bow spring centralizer installed on an expandable casing string and restrained in the collapsed configuration by restraining bands that rupture, upon expansion of the casing string, to deploy the bow spring centralizer and provide stand-off between the expanded casing string and the wall of the borehole. In one embodiment, the bow spring centralizer comprises landings for receiving and retaining the bands for restraining the centralizer in the collapsed configuration. In another embodiment, the bands are secured to the centralizer to prevent separation of the ruptured bands from the deployed centralizer.

Abstract: A method of forming a centralizer where a flat plate is created into a tubular where the flat plate is typically rolled so that two sides of the plate contact one another and are then linked, typically by welding. Openings are then created in the tubular such that there are no corners or other points that stress cracks may originate. Once the openings are created the remaining material between adjacent openings forms ribs. The openings created in the tubular are generally aligned with the long axis of the tubular. The material at the upper and lower end of the flat plate where openings were not created serve as circumferential collars. The ribs may be radially outwardly expanded in order to provide adequate stand-off. In many instances the ribs will also be hardened by heat treating or other hardening processes.

Abstract: A bow-spring centralizer (6) includes bow springs (34), moving collars (20) secured to each end of each bow spring, and interlocked stop collars (10). Extendable collars (8) may each be formed of a moving collar (20) movably interlocked with a stop collar (10). The centralizer (6) may be formed from a tube cut using a laser to create two extendable collars coupled by bow springs. Each extendable collar may include heads (12) integrally formed on extensions (26) protruding from a collar (stop collar or moving collar). The heads may be generally rectangular, arrow, or teardrop-shaped head or some other shape. Each head may be slidably captured within a chamber (24) on the interlocked collar (moving collar or stop collar). The extensions of each interlocked tubular member define the outer walls of the chamber in which a head of the interlocked tubular member is slidably captured.

Abstract: A stop collar is assembled using a method including the steps of receiving a bore of a base having a set of fingers extending along an exterior of a tubular, receiving a bore of a sleeve onto the tubular adjacent the set of fingers, and receiving the sleeve onto the set of fingers in an interference-fit. In alternate embodiments, the base comprises a plurality of angularly distributed fingers and/or the base comprises a gap to permit conformance of the base to the tubular. A fingerless base may cooperate with one or more separate fingers to form a base. In an embodiment of the method, the sleeve may be thermally expanded prior to the step of receiving the sleeve onto the set of fingers. The sleeve may be heated to expand the bore prior to being received onto the set of fingers.