Abstract: A cutting element assembly includes a cutting element and a sleeve having a cutter-receiving aperture configured to receive at least a portion of the cutting element within the cutter-receiving aperture. The cutting element assembly may also include a retention element rotatably coupling the cutting element to the sleeve and a biasing member disposed between the cutting element and the sleeve. The biasing member may be configured to bias the cutting element relative to the sleeve. A method of forming a downhole tool includes forming a bit body including at least one blade, securing at least one sleeve to the blade, disposing at least one biasing member within the cutter-receiving aperture, and inserting a cutting element into the cutter-receiving aperture of the at least one sleeve, such that the at least one biasing member is disposed between the at least one sleeve and the cutting element.

Abstract: A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

Abstract: A tool for drilling a borehole through a formation. The tool comprises a body, blades having rotationally leading surfaces extending from the tool body, cutting elements secured at least partially within cutting element pockets, and linear or rounded transition surfaces between the cutting element pockets and the rotationally leading surface of the blades. The rounded transition surfaces have a radius of curvature between about 3 and 150 millimeters.

Abstract: An earth-boring tool includes a body having a plurality of blades. Each blade of the plurality of blades extends axially and radially relative to a center longitudinal axis of the body. The earth-boring tool further includes a plurality of cutting elements secured within the plurality of blades and at least one protrusion trailing at least one cutting element of the plurality of cutting elements in a direction of intended rotation of the earth-boring tool and extending along a lateral side of a blade of the plurality of blades in which the at least one cutting element is secured. The earth-boring tool may further include a pocket extending into the at least one blade from a rotationally leading face of the at least one blade in at least a shoulder region of the at least one blade.

Abstract: A drill bit including a body having a face and a plurality of blades disposed on the face of the body. Each of the plurality of blades may have a row of cutters disposed thereon, and the rows of cutters may collectively define a cutting profile of the drill bit. At least some of the cutters along the cutting profile may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters along the cutting profile may be less than 20°.

Abstract: A drill bit including a body having a face and a bit axis. The face includes a cone region disposed about the bit axis, a nose region disposed radially outward from the cone region, and a shoulder region disposed radially outward from the nose region. The drill bit further includes a first plurality of cutters defining a first cutting profile, and a second plurality of cutters defining a second cutting profile different from the first cutting profile. The second plurality of cutters are not back-up cutters to the first plurality of cutters.

Abstract: An ultra-hard cutting element for use in a drill bit, such as a percussion drill bit, a rotary cone drill bit, a drag bit, or a reamer. The ultra-hard cutting element includes a base portion, an extension portion on an end of the base portion, and a lip on an outer surface of the extension portion. At least a portion of the outer surface of the extension portion includes an ultra-hard abrasive material. The ultra-hard abrasive material may be polycrystalline diamond or polycrystalline cubic boron nitride.

Abstract: A drill bit including a body having a face, a blade disposed on the face, and a row of cutters disposed on the blade. At least some of the cutters may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters may be less than 20°.

Abstract: A bladeless polycrystalline diamond compact (PDC) drill bit includes a head having a plurality of knots protruding from a drilling face of the head. Each of the plurality of knots includes a single cutter. Each of the cutters is arranged about a central axis of the head such that each cutter has a unique radial position and angular position relative to the central axis. The head defines at least one fluid port extending through the drilling surface.

Abstract: A downhole cutting tool may include tool body; a first blade extending from the tool body; a plurality of cutting elements attached to the first blade, the plurality of cutting elements comprising at least two types of cutting elements, wherein the first blade extends from the tool body to a first height adjacent a first type of cutting element and a second height, different from the first height, adjacent a second type of cutting element.

Abstract: A drill bit mounted on or integral to a mandrel on the distal end of a downhole motor directional assembly is provided. The drill bit is in a fixed circumferential relationship with the activating mechanism of one or more dynamic lateral pads (DLP). The technologies of the present application assist in and optionally control the extent of lateral movement of the drill bit. The technologies include, among other things, the placement and angulation of the cutting structures in the cone areas of the blades on the drill bit.

Abstract: An earth-boring tool includes a body, blades extending longitudinally and generally radially from the body, and primary cutting elements located on each blade. The earth-boring tool may include a group of at least two adjacent blades comprising the primary cutting elements and one or more first shaped inserts located rotationally behind the primary cutting elements, and one or more additional blades comprising the primary cutting elements and one or more second shaped inserts located rotationally behind the primary cutting elements, the second shaped inserts exhibiting a greater exposure relative to the first shaped inserts. Distribution of the second shaped inserts relative to the longitudinal axis may be asymmetric with respect to the longitudinal axis of the body. Methods include drilling a subterranean formation including engaging a formation with the primary cutting elements, the first shaped inserts, and the second shaped inserts of the earth-boring tool.

Abstract: A cutting element for an earth-boring tool includes a substrate and a polycrystalline, superabrasive material secured to an end of the substrate. The polycrystalline, superabrasive material includes a first transition surface extending from an outer peripheral edge of the polycrystalline, superabrasive material and in a first direction oblique to a center longitudinal axis of the substrate and a curved, stress-reduction feature located on at least the first transition surface. Additionally, the stress-reduction feature may include an undulating edge formed in at least the first transition surface and a waveform extending from the undulating edge formed in at least the first transition surface toward the center longitudinal axis of the cutting element.

Abstract: Embodiments relate to polycrystalline diamond compacts (“PDCs”) including a polycrystalline diamond (“PCD”) table having a diamond grain size distribution selected for improving leachability. In an embodiment, a PDC includes a PCD table bonded to a substrate. The PCD table includes diamond grains exhibiting diamond-to-diamond bonding therebetween. The diamond grains includes a first amount being about 30 to about 65 volume % of the diamond grains and a second amount being about 18 to about 65 volume % of the diamond grains. The first amount exhibits a first average grain size of about 8 ?m to about 22 ?m. The second amount exhibits a second average grain size that is greater than the first average grain size and is about 15 ?m to about 50 ?m. Other embodiments are directed methods of forming PDCs, and various applications for such PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.

Abstract: A method of designing a drill bit is disclosed. The method includes determining a location of a bit coordinate system in a wellbore coordinate system and generating a bit profile based on an angular coordinate around a wellbore axis of a wellbore and the location of the bit coordinate system. The bit profile is based on a cutting edge of a first cutting element on an exterior portion of a first blade. The method also includes determining a cutting layer volume based on the bit profile and identifying a weak zone based on the cutting layer volume being less than a predefined minimum cutting layer volume. The method includes determining a location for a second cutting element on the exterior portion of a second blade based on the weak zone.

Abstract: A downhole drilling tool designed for drilling a wellbore is disclosed. The drilling tool includes a bit body, and a first plurality of blades and a second plurality of blades on exterior portions of the bit body. A first group of cutting elements is located on exterior portions of the first plurality of blades. A second group of cutting elements is located on the second plurality of blades and under-exposed with respect to the first group of cutting elements. The first and second plurality of blades and the first group and second groups of cutting elements cooperate with each other to form a composite bit face profile such that each respective group of at least three neighbor cutting elements on the composite bit face profile is force balanced with respect to each other.

Abstract: An earth-boring tool includes a body, blades extending longitudinally and generally radially from the body, and cutting elements located on each blade. The earth-boring tool may also include a first group of at least two adjacent blades comprising the cutting elements proximate a front cutting edge of the blades and one or more shaped inserts located rotationally following the cutting elements, and a second group of one or more additional blades comprising the cutting elements proximate the front cutting edge of the blades while being entirely free of the one or more shaped inserts. Methods include drilling a subterranean formation including engaging a formation with the cutting elements and the shaped inserts of the earth-boring tool, the shaped inserts secured at selected locations on two or more adjacent blades of the first group of blades while the second group of blades is entirely free of the shaped inserts.

Abstract: Methods of drilling earth formations may involve removing a portion of an underlying earth formation utilizing cutting elements of an earth-boring drill bit. A rotational speed of the drill string may be sensed utilizing a first sensor. A rate of penetration of the drill string during advancement of the earth-boring drill bit may be sensed utilizing a second sensor. An instantaneous average depth of cut of cutting elements of the earth-boring drill bit may be determined utilizing a control unit to calculate the instantaneous average depth of cut based on a sensed rotational speed of the drill string and a sensed speed of advancement of the drill string. The weight on the earth-boring drill bit may be increased utilizing the drawworks when the instantaneous average depth of cut is less than the predetermined minimum depth of cut.

Abstract: An earth-boring tool comprises a body, a plurality of blades, and cutting elements. The body has a face at a leading end thereof and comprises a cone region, a nose region, a flank region, a shoulder region, and a gage region. The plurality of blades extends longitudinally and radially over the face. The cutting elements are disposed within the shoulder region of the body on different blades of the plurality of blades than one another, a first of the cutting elements exhibiting a different size than a second of the cutting elements. A method of forming an earth-boring tool and a method of forming a borehole in a subterranean formation are also described.

Abstract: A fixed cutter drill bit may include a bit body having a bit centerline a plurality of blades extending radially from the bit body, and a plurality of flow courses between the plurality of blades. Each of the plurality of blades is spaced a radial distance from the bit centerline to define a core-forming region. A plurality of cutting elements is disposed on the plurality of blades, and the plurality of cutting elements include at least one coring cutting element disposed on at least one of the plurality of blades. The at least one coring cutting element is the radially innermost cutting element on the plurality of blades, and a coring angle of the at least one coring cutting element is less than an inner cone angle thereof.

Abstract: Downhole tools with a topographical pattern, and anti-balling material over the topographical pattern. The topographical pattern may be defined by at least one of a plurality of recesses extending into a surface of a body of the tool and a plurality of protrusions protruding from the surface. Downhole tools include an insert disposed within a recess in a body, and the insert comprises an anti-balling material having a composition selected to reduce accumulation of formation cuttings on the tools when the tools are used to form or service a wellbore. Downhole tools include anti-balling material disposed over a porous mass provided over the surfaces of the tools. Methods of forming downhole tools include providing anti-balling material over features on and/or in a surface of a body of a tool. Methods of repairing downhole tools include removing an insert therefrom and disposing a replacement insert therein.

Abstract: Cutting elements for use with earth-boring tools include a cutting table having a base surface and a substrate having a support surface. An intermediate structure and an adhesion layer extend between the base surface of the cutting table and the support surface of the substrate. Earth-boring tools include such cutting elements. Methods for fabricating cutting elements for use with earth-boring tools include forming an intermediate structure on and extending from a support surface of a substrate and adhering a cutting table comprising a superabrasive material to the support surface of the substrate.

Abstract: Various embodiments are directed to a method and apparatus for horizontal directional drilling with a tool library. Various methods include storing a plurality of operational tool profiles in memory, the operational tool profiles of the plurality respectively associated with a plurality of boring tools attachable to a drill string for HHD and each of the operational tool profiles of the plurality including operating parameters for the boring tool of the plurality with which the operational profile is associated, and selectively displaying the operational tool profiles on a display screen based on user input.

Abstract: A drill bit may include a bit body including at least one blade extending at least partially over a cone region of the bit body. Additionally, the drill bit may include a plurality of cutting structures mounted to the at least one blade and a rubbing zone within the cone region of the at least one blade, wherein cutting structures within the rubbing zone have a reduced average exposure. Additionally, a method of directional drilling may include positioning a depth-of-cut controlling feature of a drill bit away from a formation to prevent substantial contact between the depth-of-cut controlling feature and rotating the drill bit off-center to form a substantially straight borehole segment. The method may also include positioning the depth-of-cut controlling feature of the drill bit into contact with the formation to control the depth-of-cut and rotating the drill bit on-center to form a substantially nonlinear borehole segment.

Abstract: In an embodiment, a polycrystalline diamond compacts (“PDC”) includes a substrate and a polycrystalline diamond (“PCD”) table bonded to the substrate. The PCD table defines an upper surface and at least one peripheral surface. The PCD table includes a plurality of bonded diamond grains. The PCD table includes a first region adjacent to the substrate that includes a metallic constituent disposed interstitially between the bonded diamond grains thereof, and a leached second region extending inwardly from the upper surface and the at least one peripheral surface that is depleted of the metallic constituent. The leached second region exhibits a leach depth profile having a maximum leach depth that is measured from the upper surface. A leach depth of the leach depth profile decreases with lateral distance from a central axis of the PCD table and toward the at least one peripheral surface.

Abstract: Cutting structures for use with downhole tools in subterranean boreholes include a blade, a plurality of primary cutting elements coupled to the blade, and at least one secondary element rotationally leading the plurality of primary cutting elements in a direction of intended rotation of the cutting structure. The at least one secondary element is coupled to the blade proximate a leading surface of the blade and comprises at least one of a rubbing surface and a cutting surface. An exposure of at least one primary cutting element of the plurality of primary cutting elements is greater than an exposure of the at least one secondary element. Downhole tools such as reamers include cutting structures. Methods of enlarging a subterranean borehole include reaming a borehole with cutting structures.

Abstract: A drill bit comprises at least one blade, comprising a plurality of cutting elements in the form of polycrystalline diamond cutters disposed on a leading edge of the blade, at least one diamond impregnated cutting region, disposed behind the leading edge of the blade, and wherein at least one of the cutters disposed on the leading, edge is an off-tip cutting element, arranged so that it does not engage with the formation during drilling until bit wear has taken place.

Abstract: The method for determining fracture toughness includes clamping a cutting element in a first orientation, exerting a confining pressure on the cutting element, applying a first load at a first distance from a perimeter of the diamond table of the cutting element, increasing the first load to a first level sufficient to fracture, and recording the first level sufficient to fracture. Then, another load is applied at another distance from a perimeter of the diamond table with another cutting element or the same cutting element in another orientation. The load is increased until fracture again. The steps are repeated at different distances and different orientations to create a profile of the fracture toughness of the cutting element. The method also includes wearing the cutting element and measuring fracture toughness at a worn distance. The profile is a more complete rating of the cutting element under drilling conditions.

Abstract: 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.

Abstract: The present disclosure provides a drill bit having cutters of different geometries, such as the combination of round cutters and scribe cutters. The drill bit includes at least one radial location at which both a round cutter and a scribe cutter are disposed. Thus, the drill bit leverages the high cutting efficiency of the scribe cutter as well as the high impact resistance of the round cutter. Additionally, the round cutter and the scribe cutter have the same maximum distance from the drill bit. Thus, the round cutter and the scribe cutter which share the same radial location contact the rock formation at substantially the same time when used in a drilling operation.

Abstract: Bits configured for drilling rock that are of the type that includes a plurality of teeth supported in pockets that are on a cutting face that is driven to rotate. The pockets are configured to allow the teeth to passively rotate while in the pockets. The present disclosure provides a bit having hardfacing around the pockets and related methods.

Abstract: A bit is assembled by forming the bit, including a bit body and a plurality of cutting components; embedding at least one electrical circuit into the bit, the circuit including a temperature sensor; and providing a module to monitor the circuits and generate an indication of bit wear. The electrical circuit may experience a change in resistance or conductivity due to wear of the bit and/or changes in an earth formation adjacent the bit. The bit wear and/or formation changes may be displayed for an operator.

Abstract: Various downhole drilling tools designed and manufactured at least in part on evaluating respective forces acting on respective groups and sets of cutting elements during simulated engagement with the downhole end of a wellbore and drilling from a first downhole formation into a second downhole formation. Simulating forces acting on each cutting element as the cutting element contacts a downhole formation may be used to force balance downhole drilling tools during transition drilling or non-uniform downhole drilling conditions. Multilevel force balanced downhole drilling tools may be designed using five respective simulations, cutter group level, neighbor cutter group level, cutter set level, group of N (N=3 or N=4) consecutive cutters level and all cutters level. Various cutter layout procedures and algorithms may also be used to design multilevel force balanced downhole drilling tools which may drill faster with higher lateral stability, especially during downhole transiting drilling conditions.

Abstract: An earth-boring tool includes a bit body, a plurality of first cutting elements, and a plurality of second cutting elements. Each of the first cutting elements includes a discontinuous phase dispersed within a continuous matrix phase. The discontinuous phase includes a plurality of particles of superabrasive material. Each of the second cutting elements includes a polycrystalline diamond compact or tungsten carbide. A method of forming an earth-boring tool includes disposing a plurality of first cutting elements on a bit body and disposing a second plurality of second cutting elements on the bit body. Another method of foaming an earth-boring tool includes forming a body having a plurality of first cutting elements and a plurality of cutting element pockets and securing each of a plurality of second cutting elements within each of the cutting element pockets.

Abstract: Cutting structures for use with downhole tools in subterranean boreholes include a blade, a plurality of primary cutting elements coupled to the blade, and at least one secondary element rotationally leading the plurality of primary cutting elements in a direction of intended rotation of the cutting structure. The at least one secondary element is coupled to the blade proximate a leading surface of the blade and comprises at least one of a rubbing surface and a cutting surface. An exposure of at least one primary cutting element of the plurality of primary cutting elements is greater than an exposure of the at least one secondary element. Downhole tools such as reamers include cutting structures. Methods of enlarging a subterranean borehole include reaming a borehole with cutting structures.

Abstract: A roof-bolt drill bit may have a forward end, a rearward end, and a rotational axis extending between the forward end and the rearward end. A cutting element for the roof-bolt drill bit may include a cutting face and a peripheral surface extending around an outer periphery of the cutting face. The cutting element may include at least one chamfer region and a peripherally extending chamfer extending from the at least one chamfer region along the outer periphery of the cutting element, a width of the at least one chamfer region being greater than a width of the peripherally extending chamfer.

Abstract: Cutting elements for earth-boring tools include one or more recesses and/or one or more protrusions in a cutting face of a volume of superabrasive material. The superabrasive material may be disposed on a substrate. The cutting face may be non-planar. The recesses and/or protrusions may include one or more linear segments. The recesses and/or protrusions may comprise discrete features that are laterally isolated from one another. The recesses and/or protrusions may have a helical configuration. The volume of superabrasive material may comprise a plurality of thin layers, at least two of which may differ in at least one characteristic. Methods of forming cutting elements include the formation of such recesses and/or protrusions in and/or on a cutting face of a volume of superabrasive material. Earth-boring tools include such cutting elements, and methods of forming earth-boring tools include attaching such a cutting element to a tool body.

Abstract: A method of forming a cutting element for an earth-boring tool. The method includes providing diamond particles on a supporting substrate, the volume of diamond particles comprising a plurality of diamond nanoparticles. A catalyst-containing layer is provided on exposed surfaces of the volume of diamond nanoparticles and the supporting substrate. The diamond particles are processed under high temperature and high pressure conditions to form a sintered nanoparticle-enhanced polycrystalline compact. A cutting element and an earth-boring tool including a cutting element are also disclosed.

Abstract: A cutting element is provided having a substrate and an ultra hard material cutting layer over the substrate. The cutting layer includes a surface portion for making contact with a material to be cut by the cutting element. The surface portion in cross-section has a curvature that has a varying radius of curvature. A bit incorporating such a cutting element is also provided.

Abstract: A drill bit for drilling a borehole in an earthen formation includes a first blade having a cutter-supporting surface. The cutting profiles of cutting faces of primary cutter elements mounted to the cutter-supporting surface define an outermost cutting profile Po in rotated profile view. A stabilizing member may be included, having an end distal the cutter-supporting surface including a tip. The tip may be offset from the outermost cutting profile Po in rotated profile view.

Abstract: A drill bit has a bit body with a plurality of fixed blades and a plurality of cutters disposed on the plurality of blades. The plurality of cutters includes a plurality of flat shear type cutters and at least one conical shaped cutter, wherein the plurality of flat shear type cutters define a cutter profile.

Abstract: A method of making a drill bit having the following steps: placing matrix material in a bit body mold; placing a metal blank in the bit body mold; placing a binder material in the bit body mold with the binder material proximate the matrix material and the metal blank; and exposing binder material to microwave radiation, whereby binder material and other constituents is heated to a selected temperature to allow binder material to melt and to infiltrate matrix material. A method of heating selected portions of a drill bit comprising: placing the drill bit in an insulative oven having a wave guide of microwave radiation from a microwave generator; positioning a portion of the drill bit to be heated proximate the wave guide; and exposing the portion of the drill bit to be heated to microwave radiation, wherein the portion of the drill bit is heated without overheating remaining portions of the drill bit.

Abstract: A rotary drag bit has one or more fixed composite cutting structures formed from a plurality of discrete prefabricated cutters that abut each other along complementary side surfaces, the composite cutting structure being placed and oriented on the cutting face of the rotating body so that the composite cutting structure presents a cutting profile that does not expose any portion of the cutting face that is between or behind the composite cutting structure, with respect to the direction of travel of the composite cutting structure during boring, to the uncut earth formation as the body is rotated during boring.

Abstract: A cutting tool cutting tool may include a tool body having a plurality of blades extending radially therefrom; and a plurality of rotatable cutting elements mounted on at least one of the plurality of blades, wherein the plurality of rotatable cutting elements are mounted on the at least one blade in a nose and/or shoulder region of the cutting tool at a side rake angle ranging from about 10 to about 30 degrees or ?10 to about ?30 degrees.

Abstract: A drill bit for drilling a borehole in earthen formations comprises a bit body including a cone region, a shoulder region, and a gage region. In addition the bit comprises a first primary blade and a second primary blade. Further, the bit comprises a plurality of primary cutter elements mounted to the first primary blade in different radial positions. Still further, the bit comprises a plurality of primary cutter elements mounted to the second primary blade in different radial positions. Moreover, a first primary cutter element of the plurality of primary cutter elements on the first primary blade and a first primary cutter element of the plurality of primary cutter elements on the second primary blade are each positioned in the cone region and are redundant. The shoulder region has a total cutter redundancy percentage that is less than a total cutter redundancy percentage in the cone region.

Abstract: A shear claw drill bit includes a bit body and a plurality of pick receptacles fixedly attached to the bit body. Each pick receptacle has a pick cavity. The shear claw drill bit further includes a plurality of picks. Each pick has a cutter cavity. The shear claw drill bit also includes a plurality of polycrystalline diamond compact (PDC) cutters. Each PDC cutter is disposed in the cutter cavity of a respective pick of the plurality of picks. A portion of each PDC cutter protrudes out of the cutter cavity of the respective pick.

Abstract: A fixed cutter drill bit having a bit axis and a gauge diameter. The drill bit includes a bit body having a proximal end, a distal end, and a plurality of blades extending from the distal end toward the proximal end. The blades define a cutting profile between the bit axis and the gauge diameter. The drill bit further includes a plurality of cutters attached to the blades in a cutter layout. The cutter layout may include a balanced cutter pattern extending from the bit axis toward the gauge diameter. The cutter layout may include one or more sets of shared cutters, wherein each set of shared cutters includes a trailing shared cutter and a leading shared cutter. The blades may define pairs of makeup surfaces and breaker surfaces. The drill bit may include a breaker upset for engaging with a device for supporting the drill bit.

Abstract: A fixed cutter drill bit may include a bit body having a bit centerline; a plurality of blades extending radially from the bit body and separated by a plurality of flow courses therebetween, each of the plurality of blades being spaced a radial distance from the bit centerline to define a core-forming region; a plurality of cutting elements disposed on the plurality of blades, the plurality of cutting elements comprising at least one coring cutting elements disposed on at least one of the plurality of blades, the at least one coring cutting elements being the radially innermost cutting element on the plurality of blades, wherein a coring angle of the coring cutting element is less than a inner cone angle thereof.

Abstract: Earth-boring drill bits may include a bit body including blades extending radially over a face of the earth-boring drill bit and cutting elements attached to each blade. Only cutting elements including planar cutting faces may be attached to at least one of the blades. Only cutting elements including nonplanar cutting faces may be attached to at least another of the blades. Only cutting elements including planar cutting faces or only cutting elements including nonplanar cutting faces may be attached to each of the blades. Only cutting elements including nonplanar cutting faces may be attached to a number of the blades that may be unequal to a number of the blades to which only cutting elements comprising planar cutting faces may be attached.

Abstract: A downhole cutting tool may include a tool body; a plurality of blades extending azimuthally from the tool body; and a plurality of cutting elements disposed on the plurality of blades, the plurality of cutting elements comprising: at least two non-planar cutting elements comprising a substrate and a diamond layer having a non-planar cutting end, wherein at least one of the at least two conical cutting elements has a positive back rake angle or positive side rake angle, and at least one of the at least two non-planar cutting elements has a negative back rake angle or a negative side rake angle.