In one embodiment, a radio-frequency identification device for use in a wellbore includes a housing made of a polymer; and an antenna disposed in the housing. The polymer may be selected from the group consisting of an elastomer, a plastic, a rubber, a thermoplastic elastomer, and combinations thereof. The RFID device may also include a fill material disposed in the housing.

A stabilizer for use in a wellbore string, the stabilizer having an elongate body having an upper end for connection to the wellbore string and a lower end for connection to a wellbore string, a long axis between the ends and an outer surface; and a first cutting ring mounted on the elongate body and exposed on the outer surface with an annular outer surface of the first cutting ring encircling the elongate body.

A stabilizer for use in a wellbore string, the stabilizer having an elongate body having an upper end for connection to the wellbore string and a lower end for connection to a wellbore string, a long axis between the ends and an outer surface; and a first cutting ring mounted on the elongate body and exposed on the outer surface with an annular outer surface of the first cutting ring encircling the elongate body.

A mud motor has integrated rotatable reamer elements. The reamer elements may be located directly radially outwardly of a rotor of the mud motor on an outer surface of the mud motor. The reamer elements may be applied to provide one or more of sizing a wellbore, smoothing a wellbore and stabilizing a bottom hole assembly and/or drill bit during drilling. The reamer elements may project from pockets formed in an outside surface of the mud motor. Axes of rotation of the reamer elements may be parallel to and/or skewed relative to a longitudinal centerline of the mud motor. Reamer devices that connect at couplings between drill string sections may be used together with the mud motor or applied separately of the mud motor. The reamer devices include inwardly-projecting elements that engage gaps between the drill string sections.

A mud motor has integrated rotatable reamer elements. The reamer elements may be located directly radially outwardly of a rotor of the mud motor on an outer surface of the mud motor. The reamer elements may be applied to provide one or more of sizing a wellbore, smoothing a wellbore and stabilizing a bottom hole assembly and/or drill bit during drilling. The reamer elements may project from pockets formed in an outside surface of the mud motor. Axes of rotation of the reamer elements may be parallel to and/or skewed relative to a longitudinal centerline of the mud motor. Reamer devices that connect at couplings between drill string sections may be used together with the mud motor or applied separately of the mud motor. The reamer devices include inwardly-projecting elements that engage gaps between the drill string sections.

The invention provides a downhole borehole traction apparatus (10) and method of use. The apparatus comprises a body comprising a borehole engaging section wherein the borehole engaging section comprises an outer surface comprising at least one thread. The at least one thread comprises a crest surface (32), a leading surface (30), and a trailing surface (28) having a curvilinear shape. The at least one thread has a low pressure generation means comprising one or more formations.

Provided is a two part drilling and running tool, a downhole tool, a well system, and a method for forming a well system. The two part drilling and running tool, in at least one aspect, includes a smaller assembly coupled to an end of a conveyance, the smaller assembly having a spline or slot located along an entire length (L.sub.S) thereof. The two part drilling and running tool, in accordance with this aspect, further includes a larger bit assembly slidably coupled to the conveyance, the larger bit assembly including an other of the slot or spline, wherein the spline or slot in the smaller assembly and the other of the slot or spline in the larger bit assembly are configured to engage one another to rotationally fix the smaller assembly relative to the larger bit assembly as the smaller assembly and the larger bit assembly slidingly engage one another.

Provided is a two part drilling and running tool, a downhole tool, a well system, and a method for forming a well system. The two part drilling and running tool, in at least one aspect, includes a smaller assembly coupled to an end of a conveyance, the smaller assembly having a spline or slot located along an entire length (L.sub.S) thereof. The two part drilling and running tool, in accordance with this aspect, further includes a larger bit assembly slidably coupled to the conveyance, the larger bit assembly including an other of the slot or spline, wherein the spline or slot in the smaller assembly and the other of the slot or spline in the larger bit assembly are configured to engage one another to rotationally fix the smaller assembly relative to the larger bit assembly as the smaller assembly and the larger bit assembly slidingly engage one another.

A stop collar for mounting to a downhole tubular includes: a cylindrical housing having a threaded inner surface and a tapered inner surface; a compressible slip ring having teeth formed in an inner surface thereof and a pair of tapered outer surfaces; a cam ring having a tapered inner surface; a seal receivable in the housing; a cylindrical bolt having a threaded outer surface. A natural outer diameter of each ring is greater than a minor diameter of the threaded surfaces. Screwing the threaded surfaces of the housing and the bolt is operable to drive the tapered surfaces together and compress the seal, thereby compressing the slip ring such that the teeth engage a periphery of the tubular and energizing the seal into engagement with the periphery of the tubular.

A stop collar for mounting to a downhole tubular includes: a cylindrical housing having a threaded inner surface and a tapered inner surface; a compressible slip ring having teeth formed in an inner surface thereof and a pair of tapered outer surfaces; a cam ring having a tapered inner surface; a seal receivable in the housing; a cylindrical bolt having a threaded outer surface. A natural outer diameter of each ring is greater than a minor diameter of the threaded surfaces. Screwing the threaded surfaces of the housing and the bolt is operable to drive the tapered surfaces together and compress the seal, thereby compressing the slip ring such that the teeth engage a periphery of the tubular and energizing the seal into engagement with the periphery of the tubular.