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.

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.

This disclosure relates to a percussive drill bit comprising PCD studs and a hard facing material that is strategically located to minimise stud pop outs and the amount of hard facing material used.

This disclosure relates to a percussive drill bit comprising PCD studs and a hard facing material that is strategically located to minimise stud pop outs and the amount of hard facing material used.

A reamer used in downhole oil well operations, particularly in reaming while drilling applications includes a plurality of helical blades. Each blade extends along a center axis of the reamer body and includes a sequence of a sloping leading edge, a central blade length, and a sloping trailing edge. Each edge slopes away from the central blade length and toward the center axis. A first series of a first type of cutter are positioned along the central blade length; separate pluralities of a second type of cutter are respectively positioned along the leading edge and the sloping trailing edge. A third type of cutter is positioned in a first transition zone located between the leading edge and the central blade length, an additional instance of the third type of cutter is positioned in a second transition zone located between the trailing edge and the central blade length.

A reamer used in downhole oil well operations, particularly in reaming while drilling applications includes a plurality of helical blades. Each blade extends along a center axis of the reamer body and includes a sequence of a sloping leading edge, a central blade length, and a sloping trailing edge. Each edge slopes away from the central blade length and toward the center axis. A first series of a first type of cutter are positioned along the central blade length; separate pluralities of a second type of cutter are respectively positioned along the leading edge and the sloping trailing edge. A third type of cutter is positioned in a first transition zone located between the leading edge and the central blade length, an additional instance of the third type of cutter is positioned in a second transition zone located between the trailing edge and the central blade length.

In an embodiment, a polycrystalline diamond table includes a plurality of bonded diamond grains and a plurality of interstitial regions defined by the plurality of bonded diamond grains. The polycrystalline diamond table may be at least partially leached such that at least a portion of at least one interstitial constituent has been removed from at least a portion of the plurality of interstitial regions by exposure to a leaching agent. The leaching agent may include a mixture having a ratio of weight % hydrofluoric acid to weight % nitric acid of about 1.0 to about 2.4, and water in a concentration of about 50 weight % to about 85 weight %. Various other materials, articles, and methods are also disclosed.

A cutting element may include a substrate, an upper surface of the substrate including a crest, the crest transitioning into a depressed region, and an ultrahard layer on the upper surface, thereby forming a non-planar interface between the ultrahard layer and the substrate. A top surface of the ultrahard layer includes a cutting crest extending along at least a portion of a diameter of the cutting element, the top surface having a portion extending laterally away from the cutting crest having a lesser height than a peak of the cutting crest.

A cutting element may include a substrate, an upper surface of the substrate including a crest, the crest transitioning into a depressed region, and an ultrahard layer on the upper surface, thereby forming a non-planar interface between the ultrahard layer and the substrate. A top surface of the ultrahard layer includes a cutting crest extending along at least a portion of a diameter of the cutting element, the top surface having a portion extending laterally away from the cutting crest having a lesser height than a peak of the cutting crest.

Embodiments of the invention relate to polycrystalline diamond compacts (“PDCs”) including a polycrystalline diamond (“PCD”) table having a structure for enhancing at least one of abrasion resistance, thermal stability, or impact resistance. In an embodiment, a PDC includes a PCD table. The PCD table includes a lower region including a plurality of diamond grains exhibiting a lower average grain size and at least an upper region adjacent to the lower region and including a plurality of diamond grains exhibiting an upper average grain size. The lower average grain size may be at least two times greater than that of the upper average grain size. The PDC includes a substrate having an interfacial surface that is bonded to the lower region of the PCD table. Other embodiments are directed methods of forming PDCs, and various applications for such PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.