A system for connecting a drill bit and pipe puller to a drill string. The system includes a downhole tool having an internal cavity and a through-hole in its wall. A coupler may be slidingly received in the cavity and connected using one or more fasteners which interconnect a groove in the coupler to the wall of the downhole tool. Fasteners used may be screws or bolts interconnecting the wall of the tool with radial holes in the coupler. Alternatively, bolts may interconnect the wall with a circumferential groove on the coupler. A drill bit may be threaded into the coupler. The coupler allows drill bits and other tools to be connected and disconnected from a downhole tool without unthreading the drill bit.

A nested drill bit assembly is disclosed for drilling a wellbore, comprising a parent bit and at least one child bit nested within the parent bit. Each bit in the nested drill bit assembly may be driven by a respective casing that gets cemented in place as part of a drilling with casing system. The parent bit and child bit(s) may be rotated together, with the parent bit and child bit collectively defining a contiguous cutting profile for drilling an initial segment of the wellbore. A driver is then lowered into the casing for connection to the child bit to drill beyond the parent bit. The driver may be configured as a drive bit for drilling through material leftover from a cementing operation prior to connecting to the child bit.

A nested drill bit assembly is disclosed for drilling a wellbore, comprising a parent bit and at least one child bit nested within the parent bit. Each bit in the nested drill bit assembly may be driven by a respective casing that gets cemented in place as part of a drilling with casing system. The parent bit and child bit(s) may be rotated together, with the parent bit and child bit collectively defining a contiguous cutting profile for drilling an initial segment of the wellbore. A driver is then lowered into the casing for connection to the child bit to drill beyond the parent bit. The driver may be configured as a drive bit for drilling through material leftover from a cementing operation prior to connecting to the child bit.

The invention relates to reamers used in downhole oil well drilling operations, particularly in reaming while drilling applications. Presented is a reamer having an interior channel which runs along an elongate axis of the entire body of the reamer, wherein there are openings along both ends of the reamer, exposing the interior channel. Additionally presented in the reamer are a plurality of paths extending parallel to the interior channel along the exterior of the body of the reamer, and running in a helical pattern along the entirety of the exterior of the body of the reamer. Disposed within the helical paths are a plurality of cutting inserts, which cutting inserts are enabled to provides a uniform cutting surface against a well bore, which preferably improves cutting action and reduces strain on the reamer.

The invention relates to reamers used in downhole oil well drilling operations, particularly in reaming while drilling applications. Presented is a reamer having an interior channel which runs along an elongate axis of the entire body of the reamer, wherein there are openings along both ends of the reamer, exposing the interior channel. Additionally presented in the reamer are a plurality of paths extending parallel to the interior channel along the exterior of the body of the reamer, and running in a helical pattern along the entirety of the exterior of the body of the reamer. Disposed within the helical paths are a plurality of cutting inserts, which cutting inserts are enabled to provides a uniform cutting surface against a well bore, which preferably improves cutting action and reduces strain on the reamer.

A drill bit for a drill assembly including a friction bolt defining a longitudinal axial passage, the drill bit being adapted to be releasibly attached to the friction bolt and comprising: (i) a leading end including a cutting part; (ii) a following end; and (iii) an outer surface defining a friction bolt engaging means adapted to releasibly engage with the leading end of the friction bolt.

The disclosure relates to embodiments of horizontal directional drilling equipment and methods for horizontal directional drilling techniques including a reamer head comprising a frustoconical body, wherein the frustoconical body defines a cavity configured to receive at least one bearing; and a plurality of teeth mounted to the frustoconical body. An imaginary apex of the frustoconical body is superimposed on the centerline of a reamer or reaming apparatus for reaming of an underground arcuate path. In another embodiment the reamer head is a progressive independently segmented reaming head. A plurality reaming heads are mounted to a reaming apparatus for reaming of an underground arcuate path.

The disclosure relates to embodiments of horizontal directional drilling equipment and methods for horizontal directional drilling techniques including a reamer head comprising a frustoconical body, wherein the frustoconical body defines a cavity configured to receive at least one bearing; and a plurality of teeth mounted to the frustoconical body. An imaginary apex of the frustoconical body is superimposed on the centerline of a reamer or reaming apparatus for reaming of an underground arcuate path. In another embodiment the reamer head is a progressive independently segmented reaming head. A plurality reaming heads are mounted to a reaming apparatus for reaming of an underground arcuate path.

The force modulation system for a drill bit includes a cutter, a holder, a holder retention device, and a first force member made of a first woven material. The cutter fits in the holder, and the holder fits in the drill bit. The holder retention device exerts a holder retention force in a first direction. The first force member exerts a first force in a second direction. The second direction is angled offset to the first direction so as that a cutting profile of the force modulation system is variable. There can also be a second force member of a second woven material to exert a second force in the first direction for more variability of the cutting profile in the first direction. The second force member can be made integral with the first force member, including the first woven material and the second woven material being the same material.

The force modulation system for a drill bit includes a cutter, a holder, a holder retention device, and a first force member made of a first woven material. The cutter fits in the holder, and the holder fits in the drill bit. The holder retention device exerts a holder retention force in a first direction. The first force member exerts a first force in a second direction. The second direction is angled offset to the first direction so as that a cutting profile of the force modulation system is variable. There can also be a second force member of a second woven material to exert a second force in the first direction for more variability of the cutting profile in the first direction. The second force member can be made integral with the first force member, including the first woven material and the second woven material being the same material.