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 and a second stop collars 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: Apparatus for reducing torque on a drill string includes a first bearing assembly, a second bearing assembly, and a bearing sleeve. The first and second bearing assemblies are disposed on and clamped onto a tubular portion of a drill pipe of the drill string, and each include a first and second section. The bearing sleeve is disposed on the drill pipe such that the bearing sleeve is maintained in an axial position relative to the drill pipe by the first bearing assembly and the second bearing assembly. Each of the first and second bearing assemblies have a first diameter portion and a second diameter portion that is smaller than the first diameter portion. The second diameter portion of the first bearing assembly and the second diameter portion of the second bearing assembly are disposed adjacent to each other and the bearing sleeve is disposed around the adjacent second diameter portions.

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 (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 centralizer assembly includes a centralizer configured to centralize a tubular in a wellbore. The centralizer includes a first end collar, a second end collar, and ribs extending between the first and second end collars. The assembly also includes a first stop collar disposed adjacent the first end collar and including an anchor. The anchor defines a generally rectangular anchor window extending therethrough. The anchor is configured to bear on an anchoring material secured to the tubular and received through the anchor window. The anchor material includes a thermal spray applied to the tubular. The first end collar is prevented from rotation with respect to the first stop collar.

Abstract: A stop collar for a tubular and method for installing a stop collar on a tubular. The stop collar includes a flexible member extending circumferentially around the tubular more than once. A tension force on the flexible member causes the flexible member to apply a radially-inward gripping force on the tubular. The stop collar may also include a shield disposed around at least a portion of the flexible member, to protect the flexible member in a downhole environment. The stop collar may also or instead include an adhesive disposed radially between the flexible member and the tubular.

Abstract: An apparatus for securing to a tubular includes a tubular base configured to be disposed around the tubular, the base defining a longitudinal central axis therethrough and including axial ends. The apparatus includes fingers extending from at least one of the axial ends of the base and substantially parallel to the longitudinal central axis. The fingers are separated circumferentially apart by slots, at least one of which does not extend across the base. The apparatus includes a sleeve configured to be disposed around the tubular and slid straight axially over the fingers, such that an elasticity of the sleeve provides a radially-inward gripping force on the fingers. The gripping force prevents the base, the plurality of fingers, and the sleeve from rotating relative to the tubular and from moving axially relative to the tubular. The sleeve may abut a stop wall of the base when slid onto the fingers.

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 and a second stop collars 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, method, and centralizer assembly. For example, the centralizer assembly includes a first stop collar fixed in place on a tubular, and a first end collar that is sized to slide axially over the first stop collar. The centralizer assembly also includes a first retainer coupled with the first end collar. The first retainer prevents the first stop collar from sliding past the first stop collar in at least one axial direction. The assembly also includes a plurality of ribs coupled with the first end collar and configured to engage a surrounding tubular in which the tubular is disposed.

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: Apparatus, methods, and systems for preconditioning and/or testing a centralizer, and a preconditioned centralizer, are provided. The apparatus includes a restrictor positionable around a tubular and having an inner diameter that is greater than an outer diameter of the tubular. The apparatus also includes a driver configured to translate the restrictor relative to the tubular in at least a first axial direction. The restrictor is configured to engage a centralizer attached to the tubular, and the restrictor is configured to at least partially collapse flexible ribs of the centralizer when the driver axially translates the restrictor across at least a portion of the flexible ribs.

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: Apparatus for reducing torque on a drill string includes a first bearing assembly, a second bearing assembly, and a bearing sleeve. The first and second bearing assemblies are disposed on and clamped onto a tubular portion of a drill pipe of the drill string, and each include a first and second section. The bearing sleeve is disposed on the drill pipe such that the bearing sleeve is maintained in an axial position relative to the drill pipe by the first bearing assembly and the second bearing assembly. Each of the first and second bearing assemblies have a first diameter portion and a second diameter portion that is smaller than the first diameter portion. The second diameter portion of the first bearing assembly and the second diameter portion of the second bearing assembly are disposed adjacent to each other and the bearing sleeve is disposed around the adjacent second diameter portions.

Abstract: A centralizer for centralizing a tubular in a wellbore, and a method of manufacturing a centralizer. The centralizer may include a plurality of ribs spaced circumferentially apart from one another around the tubular. Each of the ribs may include a first end section, a second end section, and a middle section extending between the first and second end sections. A first plurality of spacers may be spaced circumferentially apart from one another around the tubular. Each of the first plurality of spacers may be positioned circumferentially between two of the plurality of ribs. The first plurality of spacers and the first end sections of the plurality of ribs may be axially aligned and together at least partially define a first end collar.

Abstract: An attachment apparatus for attaching to a tubular. The apparatus may include a flexible member extending circumferentially around the tubular more than once. A tension force on the flexible member may cause the flexible member to apply a first radially-inward gripping force on the tubular. An annular sleeve may be positioned radially-outward from the flexible member. The sleeve may apply a second radially-inward gripping force on the flexible member and the tubular.

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: Apparatus, methods, and systems for preconditioning and/or testing a centralizer, and a preconditioned centralizer, are provided. The apparatus includes a restrictor positionable around a tubular and having an inner diameter that is greater than an outer diameter of the tubular. The apparatus also includes a driver configured to translate the restrictor relative to the tubular in at least a first axial direction. The restrictor is configured to engage a centralizer attached to the tubular, and the restrictor is configured to at least partially collapse flexible ribs of the centralizer when the driver axially translates the restrictor across at least a portion of the flexible ribs.

Abstract: A centralizer for centralizing a tubular in a wellbore, and a method of manufacturing a centralizer. The centralizer may include a plurality of ribs spaced circumferentially apart from one another around the tubular. Each of the ribs may include a first end section, a second end section, and a middle section extending between the first and second end sections. A first plurality of spacers may be spaced circumferentially apart from one another around the tubular. Each of the first plurality of spacers may be positioned circumferentially between two of the plurality of ribs. The first plurality of spacers and the first end sections of the plurality of ribs may be axially aligned and together at least partially define a first end collar.

Abstract: A stop collar for a tubular and method for installing a stop collar on a tubular. The stop collar includes a flexible member extending circumferentially around the tubular more than once. A tension force on the flexible member causes the flexible member to apply a radially-inward gripping force on the tubular. The stop collar may also include a shield disposed around at least a portion of the flexible member, to protect the flexible member in a downhole environment. The stop collar may also or instead include an adhesive disposed radially between the flexible member and the tubular.

Abstract: A downhole tool including a body configured to be positioned on an outer surface of a tubular. A flexible member may extend circumferentially around the body more than once. The body may be positioned radially-between the outer surface of the tubular and the flexible member, and a tension force on the flexible member may cause the flexible member to apply a radially-inward gripping force on the body and the tubular.