Rotary drill bits may include on or more cutting element assemblies which include a cutter and a mounting system. In one embodiment, the mounting system includes a housing, a first bearing component disposed within the housing, and a second bearing component associated with the cutting element. In certain embodiments, the bearing components may comprise a table of superhard material bonded with a substrate. In one or more embodiments, the bearing components may include bearing surfaces that are arcuate. For example, the bearing surfaces may be substantially spherical (a portion of a sphere). The bearing components may be arranged to act as a radial bearing as well as a thrust bearing for the cutting element, enabling the cutting element to rotate about a longitudinal axis of the cutter, relative to the housing, while also enabling the longitudinal axis of the cutter to be displaced (change angles) relative to the housing.

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 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.

A method of manufacturing a roller cone includes machining a cone blank and thereby defining one or more land surfaces and one or more insert grooves on the cone blank, surface hardening the cone blank, and milling a plurality of recesses into at least one of the one or more land surfaces. The method further includes subjecting the cone blank to a quenching process, forming an insert hole at each recess, and inserting an insert into each insert hole.

A method of manufacturing a roller cone includes machining a cone blank and thereby defining one or more land surfaces and one or more insert grooves on the cone blank, surface hardening the cone blank, and milling a plurality of recesses into at least one of the one or more land surfaces. The method further includes subjecting the cone blank to a quenching process, forming an insert hole at each recess, and inserting an insert into each insert hole.

Rotary drill bits may include on or more cutting element assemblies which include a cutter and a mounting system. In one embodiment, the mounting system includes a housing, a first bearing component disposed within the housing, and a second bearing component associated with the cutting element. In certain embodiments, the bearing components may comprise a table of superhard material bonded with a substrate. In one or more embodiments, the bearing components may include bearing surfaces that are arcuate. For example, the bearing surfaces may be substantially spherical (a portion of a sphere). The bearing components may be arranged to act as a radial bearing as well as a thrust bearing for the cutting element, enabling the cutting element to rotate about a longitudinal axis of the cutter, relative to the housing, while also enabling the longitudinal axis of the cutter to be displaced (change angles) relative to the housing.