Abstract: A rotary drill bit having blades with cutting elements disposed on exterior portions thereof may be formed with either a continuous cutting zone or a substantially continuous cutting zone between the last cutting element on each blade and an adjacent gage pad. Such rotary drill bits may have improved steerability during the formation of a directional wellbore and/or may experience substantially reduced wear on gage pads and/or portions of each blade adjacent to respective gage pads. For some rotary drill bits an additional cutter may be disposed in one or more gage pads adjacent to the last cutting element. For other rotary drill bits a gage cutter may be disposed between and in close proximity to both the last cutting element and adjacent portions of the associated gage pad.

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: 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: A drill bit for drilling subterranean formations comprising a drill bit body including a group of primary cutting elements comprising a first primary cutting element and a second primary cutting element radially spaced apart from each other along a first radial axis. The drill bit body further including a group of backup cutting elements comprising a first backup cutting element in a secondary cutting position relative to the first primary cutting element and a second backup cutting element in secondary cutting positions relative to the second primary cutting element, wherein the first and second backup cutting elements are radially spaced apart from each other along a second radial axis different than the first radial axis and comprise a difference in cutting characteristic relative to each other of one of a backrake angle and a siderake angle.

Abstract: Earth-boring tools include a cutting element positioned on a drill bit body at a radial distance from a longitudinal axis thereof. At least two formation-engaging elements are positioned at the same radial distance from the longitudinal axis as the cutting element. The formation-engaging elements are recessed from cutting profile of the cutting element by a distance within about 10% of d, wherein d=(?*x)/(1800*y), where ? is an angle between the formation-engaging element and the cutting element, x is a rate of penetration of the drill bit body, and y is a rotation speed of the drill bit body. Additional earth-boring tools include at least one cutting element and at least two formation-engaging elements recessed from a cutting profile of the at least one cutting element at a common angle. Methods relate to forming such earth-boring tools.

Abstract: A fixed cutter drill bit that includes one or more integrally-mounted rotating disc with cutters around the circumference of the disc. Each disc is mounted to bearings to handle the torque generated and the weight on bit required to cut the formation. The mounting angle of the disc generates a torque causing the disc to rotate. As the disc rotates, new cutters are presented to the formation. The discs may vary in size, mounting location and number so as to cover entire bladed or just a certain portions of blades. The exposure of the disc could also be set to enable it to rotate while under load, e.g., the cutters on the outside of the bit may contact the formation while the inner half of the disc is protected by a fixed blade.

Abstract: A cutting tool having a tool body with a plurality of blades extending radially therefrom and a plurality of rotatable cutting elements mounted on at least one of the plurality of blades is disclosed, wherein the plurality of rotatable cutting elements are mounted on the at least one blade utilizing multiple side rake angles.

Abstract: A drilling tool including a tool body and a cutter pocket formed in the tool body, the cutter pocket including a front planar surface, a back planar surface opposite the front planar surface, a first side surface between the front and back planar surfaces, and a second side surface opposite the first side surface and between the front and back planar surfaces is disclosed herein. A method of manufacturing a drilling tool including machining a tool body having a cutter pocket in accordance with embodiments disclosed herein, disposing a cutting element in the cutter pocket, and brazing the cutting element in the cutter pocket is disclosed.

Abstract: A superabrasive cutter including a superabrasive table having a cutting face in non-perpendicular orientation with respect to a longitudinal axis of the cutter. A superabrasive cutter having a cutting face of a superabrasive table in non-parallel orientation to a back surface thereof.

Abstract: Earth-boring drill bits comprise a bit body having a plurality of radially extending blades and a plurality of cutting elements attached to the plurality of radially extending blades. Only gouging cutting elements are attached to at least one blade of the plurality of radially extending blades. Only shearing cutting elements are attached to at least another blade of the plurality of radially extending blades. Only shearing cutting elements are attached to a number of blades of the plurality of radially extending blades that is different from a number of blades of the plurality of radially extending blades to which only gouging cutting elements are attached. Methods of forming an earth-boring drill bit comprise forming a bit body including a plurality of radially extending blades. Only shearing cutting elements are attached to a number of blades different from a number of blades to which only gouging cutting elements are attached.

Abstract: In one aspect of the invention, a fixed bladed drill bit comprises a working surface comprising a plurality of blades converging at a center of the working surface and diverging towards a gauge of the bit. Each blade comprises a plurality of pointed cutting elements and another plurality of shearing cutters. The plurality of shearing cutters comprises a first shearing cutter. The first shearing cutter on each blade tracks the first shearing cutter on other blades along a common circular cutting path.

Abstract: Cutting elements for use with earth-boring tools include a cutting table having at least two sections where a boundary between the at least two sections is at least partially defined by a discontinuity formed in the cutting table. Earth-boring tools including a tool body and a plurality of cutting elements carried by the tool body. The cutting elements include a cutting table secured to a substrate. The cutting table includes a plurality of adjacent sections, each having a discrete cutting edge where at least one section is configured to be selectively detached from the substrate in order to substantially expose a cutting edge of an adjacent section. Methods for fabricating cutting elements for use with an earth-boring tool including forming a cutting table comprising a plurality of adjacent sections.

Abstract: A roof-bolt drill bit has a bit body that is rotatable about a central axis, a coupling pocket defined in the bit body, and at least one cutting element mounted to the bit body, the at least one cutting element having a non-cylindrical periphery. The at least one cutting element includes a cutting face, a cutting edge adjacent the cutting face, a back surface opposite the cutting face, and a side surface extending between the cutting edge and the back surface, at least a portion of the side surface of the at least one cutting element being bonded to a side surface of the coupling pocket. The roof-bolt drill bit includes a coupling projection extending from the at least one cutting element, the coupling projection being bonded to a coupling recess defined in the bit body.

Abstract: A hard cutting insert for use with a roof drill bit includes a first webbed notch and a second webbed notch structured and arranged on the hard insert for removing or evacuating drilling debris from an upper surface of the hard insert during a drilling operation. A roof drill bit including a hard cutting insert having a first webbed notch and a second webbed notch structured and arranged on the hard insert.

Abstract: Earth-boring tools include a body, one or more blades projecting outwardly from the body, and cutting elements carried by the blade. The cutting elements include at least one shearing cutting element and at least one gouging cutting element. Methods of forming an earth-boring tool include mounting a shearing cutting element comprising an at least substantially planar cutting face to a body of an earth-boring tool, and mounting a gouging cutting element comprising a non-planar cutting face to the body of the earth-boring tool. The gouging cutting element may be positioned on the body of the earth-boring tool such that the gouging cutting element will gouge formation material within a kerf cut in the formation material by the shearing cutting element, or between kerfs cut in the formation material by a plurality of shearing cutting elements.

Abstract: Superabrasive inserts are disclosed. More particularly, a superabrasive insert may comprise a superabrasive layer bonded to a substrate at an interface. Further, the superabrasive layer may include a central substantially planar surface, a peripheral side surface, and an arcuate peripheral surface extending between the central substantially planar surface and the peripheral side surface. In one embodiment, the arcuate peripheral surface may comprise a lateral extent and an extension depth, wherein a ratio of the lateral extent to the extension depth is at least about 1.5. In another embodiment, an arcuate peripheral surface may comprise a substantially circular arc, wherein the substantially planar surface is tangent to the substantially circular arc and a tangent reference line to the substantially circular arc forms an angle of at least about 10° with the peripheral side surface. Subterranean drilling tools (e.g., drill bits) including at least one superabrasive insert are disclosed.

Abstract: A rotary drag bit for drilling subterranean formations includes a bit body having a face extending from a centerline to a gage. A plurality of blades may be disposed on the face, and may generally extend radially outwardly toward the gage. The bit may further include a plurality of discrete impregnated cutting posts, each of which may extend outwardly from an associated blade. Each discrete impregnated cutting post angles generally toward a front edge of the associated blade and generally toward the intended direction of rotation of the bit. The rotary drag bit may further include a plurality of matrix pockets disposed on the blades. The discrete impregnated cutting posts may be housed within corresponding matrix pockets.

Abstract: A drill bit for drilling a borehole in an earthen formation includes a connection member having a pin end. In addition, the drill bit includes a bit body coupled to the connection member and configured to rotate relative to the connection member about a central axis of the bit. The bit body includes a bit face. Further, the drill bit includes a blade extending radially along the bit face. Still further, the drill bit includes a plurality of cutter elements mounted to a cutter-supporting surface of the blade. Moreover, the drill bit includes a depth-of-cut limiting structure slidably disposed in a bore extending axially from the cutter-supporting surface. The depth-of-cut limiting structure is configured to move axially relative to the bit body in response to rotation of the bit body relative to the connection member.

Abstract: A bearing element for a rotary, earth boring drag bit effectively reduces an exposure of at least one adjacent cutting element by a readily predictable amount, as well as a depth-of-cut (DOC) of the cutter. The bearing element has a substantially uniform thickness across substantially an entire area thereof. The bearing element also limits the amount of unit force applied to a formation so that the formation does not fail. The bearing element may prevent damage to cutters associated therewith, as well as possibly limit problems associated with bit balling, motor stalling and related drilling difficulties. Bits including the bearing elements, molds for forming the bearing elements and portions of bodies of bits that carry the bearing elements, methods for designing and fabricating the bearing elements and bits including the same, and methods for drilling subterranean formations are also disclosed.

Abstract: Earth boring tools with a plurality of fixed cutters have side rake or lateral rakes configured for improving chip removal and evacuation, drilling efficiency, and/or depth of cut management as compared with conventional arrangements

Abstract: Cutters for a drill bit wherein the cutters have at least one groove in a face of a superabrasive table of the cutters. The cutters may also include ribs adjacent to the at least one groove.

Abstract: A method of optimizing drill bit design and an optimized drill bit for drilling a well into an earth formation comprising a bit body; a number of blades spaced around the bit body, each blade having a curved outer edge and a forward face; a first row of cutter pockets recessed into the face along the outer edge of each blade; a second group of cutter pockets recessed into the face of each blade offset from the first row; and a plurality of cutting elements, each cutting element being brazed into a different one of the cutter pockets.

Abstract: A downhole fixed bladed bit comprises a working surface comprising a plurality of blades converging at a center of the working surface and diverging towards a gauge of the bit, at least one blade comprising a cutting element comprising a superhard material bonded to a cemented metal carbide substrate at a non-planer interface, the cutting element being positioned at a positive rake angle, and the superhard material comprising a substantially conical geometry with an apex comprising a curvature.

Abstract: A downhole cutting tool for drilling a borehole in an earthen formation may include a tool body having a tool axis and a direction of rotation about the tool axis; at least two blades attached to the tool body, the at least two blades having a leading face facing the direction of rotation of the tool body about the tool axis, a trailing face facing away from the direction of rotation of the tool body about the tool axis, and a formation facing surface extending between the leading face and the trailing face; and a plurality of cutting elements disposed on the at least two blades, each cutting element having a radial distance from the tool axis; wherein at least one blade, at its formation facing surface, comprises, between two radially adjacent cutting elements on the at least one blade, a raised depth of cut feature for each cutting element on the other of the at least two blades that are at radial distances from the tool axis intermediate the radial distances from the tool axis of the radially adjacent cutt

Abstract: A drill bit for drilling a borehole in earthen formations comprising a bit body having a bit axis and a bit face. In addition, the drill bit comprises a primary blade extending radially along the bit face, the primary blade including a cutter-supporting surface that defines a blade profile in rotated profile view extending from the bit axis to an outer radius of the bit body. The blade profile is continuously contoured and includes a plurality of concave regions. Further, the drill bit comprises a plurality of cutter elements mounted to the cutter-supporting surface of the primary blade. Each cutter element on the primary blade has a forward-facing cutting face with a cutting edge adapted to penetrate and shear the earthen formation.

Abstract: A rotary drag bit for drilling subterranean formations includes a bit body having a face extending from a centerline to a gage. A plurality of blades may be disposed on the face, and may generally extend radially outwardly toward the gage. The bit may further include a plurality of discrete impregnated cutting posts, each of which may extend outwardly from an associated blade. Each discrete impregnated cutting post angles generally toward a front edge of the associated blade and generally toward the intended direction of rotation of the bit. The rotary drag bit may further include a plurality of matrix pockets disposed on the blades. The discrete impregnated cutting posts may be housed within corresponding matrix pockets.

Abstract: A hybrid earth-boring bit comprising a bit body having a central axis, at least one, preferably three fixed blades, depending downwardly from the bit body, each fixed blade having a leading edge, and at least one rolling cutter, preferably three rolling cutters, mounted for rotation on the bit body. A rolling cutter is located between two fixed blades.

Abstract: Rotary drag bits comprise a body comprising a face at a leading end of the body. An abrasive-impregnated cutting structure is located at the face of the bit body. The abrasive-impregnated cutting structure comprises abrasive particles dispersed within a matrix material. The abrasive-impregnated cutting structure exhibits an anisotropic wear resistance. The wear resistance varies at least substantially continuously within the abrasive-impregnated cutting structure.

Abstract: In one aspect of the present invention, a drill string has a drill bit with a body intermediate a shank and a working face. The working face has a plurality of blades converging at a center of the working surface and diverging towards a gauge of the working face. At least one blade has a cutting element with a carbide substrate bonded to a diamond working end with a pointed geometry. The diamond working end also has a central axis which intersects an apex of the pointed geometry. The axis is oriented between a 25 and 85 degree positive rake angle.

Abstract: Embodiments relate to methods of manufacturing polycrystalline diamond compacts (“PDCs”). In an embodiment, a method of fabricating a PDC includes positioning a plurality of diamond particles adjacent to a cemented carbide material. The cemented carbide material includes one or more types of tungsten-containing eta phases. The method further includes subjecting the plurality of diamond particles and the cemented carbide material to a high-pressure/high-temperature process effective to sinter the plurality of diamond particles so that a polycrystalline diamond table is formed without tungsten carbide grains of the cemented carbide material exhibiting abnormal grain growth that project into the polycrystalline diamond table.

Abstract: A drill bit has a matrix bit body with a lower end face for engaging a rock formation, wherein the end face has a plurality of raised impregnated ribs extending from the face of the bit body and separated by a plurality of channels therebetween. At least one of the plurality of ribs has a leading or trailing portion thereof comprising the same the matrix material as the bit body forming a continuous body matrix.

Abstract: In one aspect, the invention provides a method for modeling the wear of a fixed cutter bit drilling earth formations. A method for determining wear of a fixed cutter drill bit includes simulating the fixed cutter drill bit drilling an earth formation; determining a cutter-formation interaction force and a relative sliding velocity of a selected area on a cutting surface on a cutter of the fixed cutter drill bit during the drilling; and calculating a wear rate of the selected area based on the cutter-formation interaction force and the relative sliding velocity.

Abstract: A fixed cutter drill bit that includes one or more integrally-mounted rotating disc with cutters around the circumference of the disc. Each disc is mounted to bearings to handle the torque generated and the weight on bit required to cut the formation. The mounting angle of the disc generates a torque causing the disc to rotate. As the disc rotates, new cutters are presented to the formation. The discs may vary in size, mounting location and number so as to cover entire bladed or just a certain portions of blades. The exposure of the disc could also be set to enable it to rotate while under load, e.g., the cutters on the outside of the bit may contact the formation while the inner half of the disc is protected by a fixed blade.

Abstract: A roof-bolt drill bit may include a bit body that is rotatable about a central axis and at least one cutting element mounted to the bit body. The at least one cutting element may include a cutting face, a cutting edge adjacent the cutting face, a back surface opposite the cutting face, and at least one coupling feature positioned adjacent the at least one cutting element. The at least one cutting element may be secured to the bit body by the at least one coupling feature.

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.

Abstract: A drill bit for drilling a borehole in an earthen formation may include a bit body having a bit axis and a direction of rotation about the bit axis; at least two blades extending azimuthally from the bit body; and a plurality of cutting elements disposed on the at least two blades; the plurality of cutting elements forming a cutting profile in a rotated profile view, each cutting element having a radial distance from the bit axis. At least one blade, at its formation facing surface, may include, between two radially adjacent cutting elements on the at least one blade, a raised depth of cut feature for each cutting element on the other of the at least two blades that are at radial distances from the bit axis intermediate the radial distances from the bit axis of the radially adjacent cutting elements on the at least one blade.

Abstract: A PDC bit includes a plurality of blades. A blade includes a primary cutter row and a secondary cutter row. Primary PDC cutters on the primary cutter row are set in accordance with a single set methodology. Backup PDC cutters on the secondary cutter row are set in accordance with a methodology wherein a radial position of each backup PDC cutter in the secondary cutter row is offset from a radial position of each primary PDC cutter in the primary cutter row. The blade further includes a tertiary cutter row. Additional backup PDC cutters on the tertiary cutter row are set in accordance with a methodology wherein a radial position of each additional backup PDC cutter in the tertiary cutter row is offset from a radial position of each primary PDC cutter in the primary cutter row. The backup cutter setting methodology is effectively radially positions the included backup PDC cutters (in the secondary cutter row and/or tertiary cutter row) between primary PDC cutters in the primary cutter row.

Abstract: A method for forming a borehole enlargement tool that includes providing a steel body structure, forming at least one rib structure from a matrix material and abrasive particles, affixing the at least one rib structure to the body structure, and affixing the steel body structure to an elongated tubular body is disclosed.

Abstract: A drill bit for drilling a borehole in earth formations may include a bit body having a bit axis and a bit face; a plurality of blades extending radially along the bit face; and a plurality of cutting elements disposed on the plurality of blades, the plurality of cutting elements comprising: at least one cutter comprising a substrate and a diamond table having a substantially planar cutting face; and at least two non-planar cutting elements comprising a substrate and a diamond layer having a non-planar cutting end, wherein in a rotated view of the plurality of cutting elements into a single plane, the at least one cutter is located a radial position from the bit axis that is intermediate the radial positions of the at least two non-planar cutting elements.

Abstract: Earth-boring tools include combinations of shearing cutting elements and gouging cutting elements on a blade of the earth-boring tools. In some embodiments, a gouging cutting element may be disposed adjacent to a shearing cutting element on a blade of an earth-boring tool. Methods of forming earth-boring tools include providing such combination of at least one shearing cutting element and at least one gouging cutting element on a blade of an earth-boring tool.

Abstract: Superabrasive inserts are disclosed. More particularly, a superabrasive insert may comprise a superabrasive layer bonded to a substrate at an interface. Further, the superabrasive layer may include a central substantially planar surface, a peripheral side surface, and an arcuate peripheral surface extending between the central substantially planar surface and the peripheral side surface. In one embodiment, the arcuate peripheral surface may comprise a lateral extent and an extension depth, wherein a ratio of the lateral extent to the extension depth is at least about 1.5. In another embodiment, an arcuate peripheral surface may comprise a substantially circular arc, wherein the substantially planar surface is tangent to the substantially circular arc and a tangent reference line to the substantially circular arc forms an angle of at least about 10° with the peripheral side surface. Subterranean drilling tools (e.g., drill bits) including at least one superabrasive insert are disclosed.

Abstract: A rotary drill bit is disclosed. The rotary drill bit may include a bit body, a cutting pocket defined in the bit body, and a cutting element rotatably coupled to the bit body. The cutting element may be positioned at least partially within the cutting pocket. The rotary drill bit may also include a rotation-inducing member adjacent to the cutting element for inducing rotation of the cutting element relative to the cutting pocket. The rotation-inducing member may include a resilient member or a vibrational member. The rotary drill bit may also include protrusions extending from an interior of the cutting pocket adjacent to an outer diameter of the cutting element. A method of drilling a formation is also disclosed.

Abstract: A fixed-cutter earth-boring tool includes a first blade carrying a first plurality of cutting elements and having a first stiffness and a second blade configured to have a second stiffness different from the first stiffness. A method of forming an earth-boring tool includes forming a bit body having a plurality of blades, and providing at least one cutting element on at least one of the plurality of blades. At least one blade of the plurality has a stiffness different from a stiffness of another blade of the plurality. A fixed-cutter earth-boring drill bit includes a first blade having a first aggressiveness, and at least one additional blade having a second aggressiveness.

Abstract: A bearing element for a rotary, earth boring drag bit effectively reduces an exposure of at least one adjacent cutting element by a readily predictable amount, as well as a depth-of-cut (DOC) of the cutter. The bearing element has a substantially uniform thickness across substantially an entire area thereof. The bearing element also limits the amount of unit force applied to a formation so that the formation does not fail. The bearing element may prevent damage to cutters associated therewith, as well as possibly limit problems associated with bit balling, motor stalling and related drilling difficulties. Bits including the bearing elements, molds for forming the bearing elements and portions of bodies of bits that carry the bearing elements, methods for designing and fabricating the bearing elements and bits including the same, and methods for drilling subterranean formations are also disclosed.

Abstract: Embodiments of the present invention include a drill bit comprised of a plurality of blades. A first plurality of the blades has cutting elements positioned substantially within the cone section of the drill bit. A second plurality of blades has cutting elements positioned substantially within the blade flank section and the blade shoulder section. Another embodiment of the first plurality of blades in which the blades end or truncate at a radial distance substantially less than the radial distance of the blade shoulder section from the center of the drill bit.

Abstract: A drill bit for drilling a borehole in earthen formations, the bit comprising: a bit body having a bit axis and a bit face including a cone region, a shoulder region, and a gage region; a first primary blade extending radially along the bit face from the cone region to the gage region; a plurality of cutter elements mounted to the first primary blade, wherein a first of the plurality of cutter elements has a planar cutting face and a second of the plurality of cutter elements has a convex cutting face; and wherein each cutting face is forward-facing.

Abstract: A drill bit employing a plurality of abrasive, particulate-impregnated cutting structures extending upwardly from a bit face and defining a plurality of fluid passages therebetween. The plurality of cutting structures may be configured as spaced posts, or as blades with circumferentially extending grooves at radially spaced intervals. Superabrasive cutting elements in the form of thermally stable diamond are placed between the posts or in the grooves, depending on the cutting structure configuration, and at a reduced exposure. Additional cutting elements may be placed in a cone of the bit surrounding a centerline thereof. The blades may extend generally radially. Additionally, discrete protrusions may extend outwardly from at least some of the plurality of cutting structures. The discrete protrusions may be formed of thermally stable diamond.

Abstract: A cutting element includes a substrate having an interface surface; and an ultrahard material layer disposed on the interface surface. An interface surface includes a plurality of surface features, wherein at least one of the plurality of surface features intersects a neighboring surface feature at a height that is intermediate an extremity of the at least one of the plurality of surface features and a base of the at least one of the plurality of surface features.

Abstract: A method of making a drill bit for drilling subterranean formations includes forming a first blade having a shape and configuration defined by one or more first parameters and forming a second blade having a shape and configuration defined by one or more second parameters. One of the first parameters is different than one of the second parameters.

Abstract: Disclosed is method for designing a fixed cutter drill bit comprising: (a) defining initial primary placement parameters for primary cutter elements; (b) repeatedly: selecting back up placement parameters for back up cutter elements; applying to a simulated formation a bit design having the combination of the defined initial primary placement parameters and the selected back up placement parameters; using the combination in the simulation and generating a value representative of a first design criteria of interest (such as resultant force on a cutter element, total out-of-balance force on the bit, resistance to slip stick, and resistance to bit vibration); comparing the generated value to a first predetermined acceptable value.