A drill bit having a rotatable ball bit includes a first bit head and a second bit head, a first set of cutters on the first bit head, and a second set of cutters on the second bit head. The rotatable ball bit is configured to rotate between a first position and a second position, wherein the first bit head is distal to the second bit head in the first position, and wherein the second bit head is distal to the first bit head in the second position. A method of operating a rotatable ball bit includes orienting the rotatable ball bit in a first position, wherein a first bit head is oriented distally, rotating the rotatable ball bit about a longitudinal axis, orienting the rotatable ball bit in a second position, wherein a second bit head is oriented distally, and rotating the rotatable ball bit about the longitudinal axis.

A drill bit having a rotatable ball bit includes a first bit head and a second bit head, a first set of cutters on the first bit head, and a second set of cutters on the second bit head. The rotatable ball bit is configured to rotate between a first position and a second position, wherein the first bit head is distal to the second bit head in the first position, and wherein the second bit head is distal to the first bit head in the second position. A method of operating a rotatable ball bit includes orienting the rotatable ball bit in a first position, wherein a first bit head is oriented distally, rotating the rotatable ball bit about a longitudinal axis, orienting the rotatable ball bit in a second position, wherein a second bit head is oriented distally, and rotating the rotatable ball bit about the longitudinal axis.

A roller cone drill bit having at least one roller cone cutter, the roller cone cutter having multiple rows of cutting elements, arranged concentrically around the axis of rotation of the roller cone. One row of cutting elements is located on the heel of the roller cone. Each of the rows of cutting elements includes both cemented tungsten carbide inserts and milled teeth as cutting elements.

A roller cone drill bit having at least one roller cone cutter, the roller cone cutter having multiple rows of cutting elements, arranged concentrically around the axis of rotation of the roller cone. One row of cutting elements is located on the heel of the roller cone. Each of the rows of cutting elements includes both cemented tungsten carbide inserts and milled teeth as cutting elements.

A drilling apparatus including a rotary cutting tool having a proximal end and a distal end and further defining a rotary axis generally extending between the proximal and distal ends. The rotary cutting tool includes a proximally directed face located between the proximal and distal ends that face mainly in a proximal direction. The rotary cutting tool also includes an angled mounting face that extends between the proximally directed face and the proximal end. The angled mounting face is angled relative to the proximally directed face and the rotary axis where one of a mounting aperture and a mounting protrusion are provided at the proximally directed face. The one of the mounting aperture and the mounting protrusion have a mounting depth that extends generally in the direction of the rotary axis. The distal end includes a feature that is configured for at least one of cutting and grinding.

A drilling apparatus including a rotary cutting tool having a proximal end and a distal end and further defining a rotary axis generally extending between the proximal and distal ends. The rotary cutting tool includes a proximally directed face located between the proximal and distal ends that face mainly in a proximal direction. The rotary cutting tool also includes an angled mounting face that extends between the proximally directed face and the proximal end. The angled mounting face is angled relative to the proximally directed face and the rotary axis where one of a mounting aperture and a mounting protrusion are provided at the proximally directed face. The one of the mounting aperture and the mounting protrusion have a mounting depth that extends generally in the direction of the rotary axis. The distal end includes a feature that is configured for at least one of cutting and grinding.

A cutter profile for a fixed cutter drill bit having a drill bit axis. The cutter profile includes a nose portion radially offset from the drill bit axis and surrounding the drill bit axis, a first cone-shaped depression centered on the drill bit axis and extending radially to the nose portion, and a second cone-shaped depression centered on the drill bit axis and extending radially toward the nose portion. A second depression diameter is smaller than a first depression diameter. A second depression maximum depth is greater than a first depression maximum depth. A second depression included angle is smaller than a first depression included angle.

A rotary drill tool for cutting rock includes a set of journal legs that rotatably mount rotating cone shaped cutters via respective bearing assemblies. A fluid supply passageway extends through the journal legs to provide a cooling and cleaning fluid to the bearings during use. A by-pass passageway extends through a base region of the spindle that mounts each cone cutter and is provided in direct fluid communication with the supply passageway to divert the fluid to a base region of the bearing assembly.

A cutting element (30) includes a substrate (40); and a body of superhard polycrystalline material (34) bonded to the substrate (40) along an interface, the body of superhard polycrystalline material having a peripheral side edge (42). The body of superhard polycrystalline material has a cutting surface (34); a plurality of spaced apart cutting edges (36) extending to the cutting surface (34) through respective chamfer portions (38), the cutting edges being spaced around the peripheral side edge; a plurality of recesses/regions (48) extending from the cutting surface (34) towards the substrate, adjacent cutting edges (36) being spaced apart by a respective one of said recesses/regions (48); and a protrusion or recessed region extending from the cutting surface about a central longitudinal axis of the cutting element. A method of making such a cutting element is also disclosed.

A cutting element (30) includes a substrate (40) having a peripheral side edge, the peripheral side edge having an associated radius of curvature; and a body of superhard polycrystalline material bonded to the substrate along an interface, the body of superhard polycrystalline material (39) having a peripheral side edge and a longitudinal axis. The body of superhard polycrystalline material (39) has a working surface (54); and a plurality of spaced apart cutting edges extending to the working surface (54) through respective chamfer portions (62), the cutting edges (61, 76) being spaced around the working surface by a further region. The cutting edges (61, 76) have an associated radius of curvature, the radius of curvature of one or more of the cutting edges being less than the radius of curvature of the substrate. A method of making such a cutting element is also disclosed.