Abstract: Cutting elements for incorporation in a drill bit are provided having a body and an ultra hard material cutting layer over an end face of the body. A plurality of abutting shallow depressions are formed on the end face of the body. A transition layer may be incorporated between the body and the ultra hard material layer. The transition layer preferably has material properties intermediate between the properties of the body and the ultra hard material layer.

Abstract: Cutting elements for incorporation in a drill bit are provided having a body having an end face interfacing with an ultra hard material cutting layer. A main depression having a nonplanar surface is formed on the substrate and extending to the peripheral edge of the substrate subjected to the highest impact loads during drilling. This edge is immediately below the edge of the cutting layer which makes direct contact with the earth formations during drilling. The main depression is formed by forming a plurality of secondary depressions or steps. A second main depression is formed by forming a plurality of secondary depressions or steps. The second main depression also extends to the peripheral edge of the substrate. An ultra hard material layer is bonded to the end face of the cutting element body over the main depressions.

Abstract: A drill bit assembly is provided for releasably retaining a polycrystalline diamond compact drill bit cutter. Two adjacent cavities formed in a drill bit body house, respectively, the disc-shaped drill bit cutter and a wedge-shaped cutter lock element with a removable fastener. The cutter lock element engages one flat surface of the cutter to retain the cutter in its cavity. The drill bit assembly thus enables the cutter to be locked against axial and/or rotational movement while still providing for easy removal of a worn or damaged cutter. The ability to adjust and replace cutters in the field reduces the effect of wear, helps maintains performance and improves drilling efficiency.

Abstract: A cutting element for earth-boring drill bits comprising a generally domed cutting surface comprising a superabrasive material, formed by a high-pressure high-temperature sintering method known in the art, integrally bonded to a cylindrical substrate having a truncated conical interfacial surface, consisting of a top surface and a circumferential shoulder joined by tapered sidewalls, and the base of the substrate being adapted for insertion into an earth-boring tool. The top surface of the substrate may form a circle, a square, or a polygon, and the sidewalls may be smooth or form one or more polygons.

Abstract: A cutter for drilling subterranean formations including a superabrasive table formed on an end face of a supporting substrate, there being an interface between the table and the end face defined by at least one annular surface centered about the centerline of the cutter in a location adjacent the side periphery of the substrate, the annular surface having an arcuate topography of an orientation and radial width sufficient to accommodate resultant loading of the cutting edge of the cutter throughout a variety of angles with vectors normal to the surface at a variety of angles such that at least one normal vector is aligned substantially parallel to the resultant loading on the cutting edge.

Abstract: The present invention provides a cutting element having a cylindrical body having a canted end face on which is formed a ultra hard material layer and a method of forming the same. One or a plurality of transition layers may be provided between the ultra hard material layer and the cutting element body.

Abstract: A cutting element, insert or compact, is provided for use with drills used in the drilling and boring of subterranean formations. This new insert, in its preferred embodiment, has a “hoop” region of polycrystalline diamond extending around the periphery of the compact to reduce the residual stresses inherent in thick diamond regions of cutters, thereby providing improved wear and durability characteristics because it avoids failures due to stresses, delaminations and fractures caused by the differences in thermal expansion coefficient between the diamond and the substrate during sintering. Moreover, this invention may provide multiple polycrystalline diamond edges as the PDC wears.

Abstract: A cutting assembly comprised of first and second superabrasive cutting elements including at least one rotationally leading cutting element having a cutting face oriented generally in a direction of intended rotation of a bit on which the assembly is mounted to cut a subterranean formation with a cutting edge at an outer periphery of the cutting face, and a rotationally trailing cutting element oriented substantially transverse to the direction of intended bit rotation and including a relatively thick superabrasive table configured to cut the formation with a cutting edge located between a beveled surface at the side of the superabrasive table and an end face thereof. A rotationally trailing cutting element may be associated with and disposed at a location on the bit at least partially laterally intermediate locations of two rotationally leading cutting elements. Drill bits equipped with the cutting assembly are also disclosed.

Abstract: The present invention provides a cutting element having a cylindrical body having a canted end face on which is formed a ultra hard material layer. One or a plurality of transition layers may be provided between the ultra hard material layer and the cutting element body.

Abstract: The present invention is directed to an improved cutting element for use with rotating downhole tools. More specifically, the present invention is directed to a compact cutter which includes unique configurations for the interface regions between the substrate the abrasive element to promote superior impact resistance and adhesion.

Abstract: A cutter comprising a superabrasive volume including a cutting face portion extending transversely across a leading face of a supporting substrate and a contiguous jacket portion extending rearwardly over the supporting substrate along a portion of its side periphery. Interfaces between the respective superabrasive volume cutting face and cap portions and adjoining surfaces of the supporting substrate are each irregular. The leading face of the substrate includes grooves extending toward the jacket at least partially across the leading face from the side of the substrate opposite the jacket. The side periphery of the substrate defining the location of the jacket is grooved at a plurality of laterally-adjacent locations with substantially axially-oriented grooves extending rearwardly from the leading face of the substrate to a position closer to the trailing face of the substrate.

Abstract: Cutter elements including pointed contact structures and elements, and rock tools or bits for carrying those elements, for chipping, cutting, and breaking non-ductile materials are disclosed. The cutter elements, the ends of which directly contact and cut through rock and other materials, have tapered contact structure ends which are flatter than those known to the prior art, obtaining increased durability. The contact elements which may be part of the contact structures are selected of materials having hardness and other characteristics in relation to those of the mounting structures, including the tapered and projecting portions, which also add durability and wear-resistance to the elements. Fixed, replaceable, and rotatable cutter elements are disclosed. Rock tools including bits are also disclosed for carrying the cutter elements, having sockets for threaded or rotatable cutter elements arranged in straight or curved rows on the head opposite the drill-string-engaging base of the tool.

Abstract: A cutter element for a drill bit. The cutter element has a base portion and an extending portion and the extending portion has either a zero draft or a negative draft with respect to the base portion. The non-positive draft allows more of the borehole bottom to be scraped using fewer cutter elements. The cutter elements having non-positive draft can be either tungsten carbide inserts or steel teeth.

Abstract: A planar or convex heel, gage, or cutting element comprising one or more layers of superhard materials bonded to a metal-carbide substrate. The substrate's perimeter is inclined and comprises one or more circumscribing grooves or furrows, or flutes, in order to permit the bonding of superhard materials below the plane of the major interface, thereby reinforcing the perimeter of the element itself. This heel, gage, or cutting element is useful in drilling applications for the oil, gas, geothermal, and mining industries.

Abstract: A chip breaker for use in a fixed-cutter, rotary-type drill bit used in drilling subterranean formations is disclosed. The chip breaker includes a knife-like protrusion positioned proximate a cutting element and adjacent or in a fluid course defined by the drill bit body. As formation chips, shavings, or cuttings are generated during drilling, the chips move over the protrusion and are split or scribed by the protrusion. Drilling fluid breaks the split or scribed chips away from the surface of the fluid course adjacent the cutting element and transports them through the junk slots. Additionally, chip splitters may be positioned on ramped surfaces that further lift the formation chips away from the surface of the fluid course.

Abstract: An improved cutting element is disclosed. The cutting element has a disc-shaped body with a front face and a backside. A ring portion formed on the front face extends around a raised central protrusion in formation of a vertical ridge. A plurality of inwardly extending, straight radial slots are formed in the raised central portion and create a plurality of vertical ridge segments. A super-abrasive compound, such as synthetic diamond, is applied to the front face. To aid in stress relief, the ridges have curved corners.

Abstract: The present disclosure sets out a method and apparatus for forming an insert body. The insert body is preferably made of hard particles of tungsten carbide commingled with particles of a binding metal alloy primarily made of cobalt. The finished component typically is a right cylinder of tungsten carbide and cobalt based alloy. It incorporates in it a diamond region which is formed of diamond particles and cobalt also. The geometry of the diamond region is preferably a sphere or a cylinder and has a curvilinear bottom face to distribute stress for structural integrity.

Abstract: A rotary drag bit and method for drilling subterranean formations including a bit body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per bit rotation, as well as to control the amount of torque experienced by the bit and an optionally associated bottomhole assembly regardless of the effective weight-on-bit. The exterior of the bit preferably includes a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute the weight of the bit against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: Angled insertable drag bit teeth having a front portion at an oblique angle to a shank portion: the front portion is nearly parallel to the direction of thrust during cutting, and is bonded, along a substantial part of its length, to a groove in the bit body. The shank portion extends down into a pocket in the bit body. Preferably the front portion is faced with a superhard material such as polycrystalline-diamond-compact.

Abstract: A rotary drag bit including exterior features to control the depth of cut by cutters mounted thereon, so as to control the volume of formation material cut per bit rotation as well as the torque experienced by the bit and an associated bottomhole assembly. The exterior features preferably precede, taken in the direction of bit rotation, cutters with which they are associated, and provide sufficient bearing area so as to support the bit against the bottom of the borehole under weight on bit without exceeding the compressive strength of the formation rock. The exterior features may be oriented and configured to function optimally at a predicted rate of penetration, or range of rates, at which the bit may be operated, such rate or rates being further optionally maximized in softer formations in light of the ability of the bit to hydraulically clear a maximum volume of formation cuttings to prevent so-called bit balling.

Abstract: A method and apparatus for improved attachment of an ultra-hard compact, especially a two-layer disk-type PCD compact, to a tool or support surface with a mechanical connection. In general the ultra-hard compact is provided with a tool-engaging threaded end protruding from the compact. The threaded end may be facilitated by a post fitted into a blind hole in the ultra-hard compact, or may be facilitated by a threaded sleeve permanently attached to the ultra-hard compact. In any case, when the ultra-hard compact is threadably engaged into a tool or support surface, the fastening means is hidden with only the wear resistant materials of the ultra-hard compact exposed.

Abstract: A cutter element for use in a drill bit, has a substrate comprising a grip portion and an extension and at least a cutting layer affixed to said substrate. The cutting layer has a cutting surface and an interface surface, and the cutting surface includes a region of residual compressive stress, which functions as a preload or prestress so as to offset the effect of localized loading due to contact with the formation during drilling.

Abstract: Cutting elements for incorporation in a drill bit are provided having a body having an end face interfacing with an ultra hard material cutting layer. A main depression having a nonplanar surface is formed on the substrate and extending to the edge of the substrate subjected to the highest impact loads during drilling. This edge is immediately below the edge of the cutting layer which makes direct contact with the earth formations during drilling. The main depression is formed by forming a plurality of secondary depressions or steps such that depth of the main depression decreases in a radial direction towards the edge of the cutting element. An ultra hard material layer is bonded to the end face of the cutting element body such that the cutting layer is the thickest over the main depression. Consequently, the cutting layer edge making contact with the earth formations during drilling has an increased thickness.

Abstract: A cutting element for use on a rotary-type earth boring drill bit for drilling subterranean formations including a segment and a support member. The support member is preferably fabricated from a tough and ductile material, such as iron, an iron-based alloy, nickel, a nickel-based alloy, copper, a copper-based alloy, titanium, a titanium-based alloy, zirconium, a zirconium-based alloy, silver, or a silver-based alloy. A bit attachment portion of the support member is securable to a bit body. A segment-receiving portion of the support member is disposable within a recess formed in the segment to secure the segment to the bit body and support the segment during use of the drill bit. Preferably, the segment is fabricated from a hard continuous phase material that is impregnated with a particulate abrasive material, such as natural diamond, synthetic diamond, or cubic boron nitride.

Abstract: Superhard material enhanced inserts and methods of making the same have been disclosed. The enhanced insert includes a body portion adapted for attachment to the earth-boring bit and a top portion for contacting an earthen formation to be drilled. The top portion includes a substrate and a layer of superhard material over a portion of the substrate other than in central region of the outer lateral face. For example, a layer of polycrystalline diamond is provided in the leading transition of the top portion, whereas the trailing transition and the central region of the outer lateral face of the top portion are substantially free of polycrystalline diamond.

Abstract: A cutter element for a drill bit. The cutter element has a base portion and an extending portion and the extending portion has either a zero draft or a negative draft with respect to the base portion. The non-positive draft allows more of the borehole bottom to be scraped using fewer cutter elements. The cutter elements having non-positive draft can be either tungsten carbide inserts or steel teeth.

Abstract: A superabrasive cutting element attachable to a drill bit for drilling subterranean formations is formed of a substrate and a superabrasive table with a three-dimensional interface comprising a continuous wave pattern extending about a central axis. Multiple outwardly directed arches of the wave pattern are oriented and configured to preferentially accommodate loading experienced by the cutting element during drilling to absorb and distribute stresses resulting therefrom. Thus, any tendency toward fracture and spalling of the superabrasive table and delamination thereof from the substrate, any of which may induce catastrophic failure of the cutting element, are substantially reduced. A rotary drill bit including such cutting elements is also disclosed.

Abstract: The residual stresses that are experienced in polycrystalline diamond cutters, which lead to cutter failure, can be effectively modified by selectively thinning the carbide substrate subsequent to high temperature, high pressure (sinter) processing, by selectively varying the material constituents of the cutter substrate, by subjecting the PDC cutter to an annealing process during sintering, by subjecting the formed PDC cutter to a post-process stress relief anneal, or a combination of those means.

Abstract: A cutting element substrate for use with an earth-boring drill bit. The substrate includes a base, or outer shell, with a cavity opening to an end thereof. The base is fabricated from an erosion-resistant and abrasion-resistant material. A core that is configured substantially complementarily to the cavity is disposed within the cavity. The core base is fabricated from a material that is more ductile than the material of the base. The core and base each includes a cutting end to which a superabrasive cutting table, such as a polycrystalline diamond compact, may be secured. The substrate may be secured within a corresponding receptacle of a bit body in order to secure a superabrasive cutting table to the bit body in a desired orientation. The present invention also includes methods of fabricating the cutting element substrate.

Abstract: A high-performance drilling stabilizer is provided that is high in both wear resistance and strength. Blades are bonded to a stabilizer body. The blade is split into at least two segments. The blade segments are bonded to the stabilizer body to form the blade. A laminate made of cemented carbide and having a laminate structure made up of at least two layers is bonded to the top of each of the blade segments. The laminate has a thickness of between 1 mm and 5 mm. The cobalt contents of the respective layers decrease stepwise from the innermost layer toward the outermost layer.

Abstract: Cutting elements providing a relatively constant superabrasive area in contact with the formation responsive to weight on bit during a substantial portion of the useful life of a circular cutting face cutting element or other cutting element exhibiting a non-linear cutting edge, for example, from about 5% diametrical wear to in excess of about 30% diametrical wear in the case of a circular cutting element, measured across the cutting face. The superabrasive table of the cutting element is configured, internally, externally, or both, to vary in depth radially and laterally, as required, so that an increase in width of the contact or wear flat area with the formation and the variation in table depth as the cutting element wears, are substantially offsetting. The rate of penetration of a drill bit so equipped may thus be maintained at a desirable magnitude without a substantial increase in weight on bit as the cutting element wears, since the superabrasive contact area is maintained relatively constant.

Abstract: The present invention provides a cutting element having a cylindrical body having a canted end face on which is formed a ultra hard material layer. One or a plurality of transition layers may be provided between the ultra hard material layer and the cutting element body.

Abstract: Enhanced inserts are formed having a cylindrical grip and a protrusion extending from the grip. An ultra hard material layer is bonded on top of the protrusion. The inserts are mounted on a rock bit and contact the earth formations off center. The ultra hard material layer is thickest at a critical zone which encompasses a major portion of the region of contact between the insert and the earth formation. Transition layers may also be formed between the ultra hard material layer and the protrusion so as to reduce the residual stresses formed on the interface between the ultra hard material and the protrusion.

Abstract: A superabrasive cutting element, the substrate of which is structured with a reduced dimension circumferential portion about which is formed an annular portion of superabrasive material, such as sintered diamond in the form of a polycrystalline diamond compact, to provide a ring- or skirt-like portion of superabrasive material at the perimeter of the cutting element to reduce residual tensile stresses existing at the perimeter of the cutting element after formation.

Abstract: A non-uniform interface is formed between a polycrystalline ultra hard material layer and a cemented tungsten carbide substrate, or a polycrystalline ultra hard material layer and a transition layer, or a transition layer and a substrate of a cutting element. A first sheet made from an intermediate material is formed and embossed on one face forming a non-uniform pattern raised in relief on the face. The embossed sheet is placed on a face of a presintered substrate. An ultra hard material sheet is formed and embossed, forming a non-uniform face complementary to the non-uniform face on the sheet of intermediate material. The ultra hard material sheet is placed over the intermediate material sheet so that the complementary faces are adjacent to each other. The assembly of substrate and sheets is sintered in a HPHT process.

Abstract: A drill for forming bores in constructional components, and including a sleeve-shaped stem (2; 12; 22; 32; 42; 52) having an axially-extending through-bore (3; 13; 23; 33; 43; 53) which opens into mouth openings (7; 10; 14; 24; 34; 44; 54) formed in opposite end sections of the stem (2; 12; 2; 32; 42; 52); a shank (5) provided at a rear end of the stem, and a drilling head (8; 15; 25; 35; 45; 55) formed of a hard material and secured in at least one slot (19; 29; 49; 59) formed in a free front end of the stem (2; 12; 22; 32; 42; 52), with a section of the drilling head (8; 15; 25; 32; 45; 55), which is embedded in the stem (2; 12; 22; 32; 42; 52), flatly engaging a material of the stem (2; 12; 22; 32; 42; 52) and being fixedly connected with the stem material.

Abstract: A cutting element, insert or compact, is provided for use with drills used in the drilling and boring of subterranean formations. This new insert, in its preferred embodiment, has a “hoop” region of polycrystalline diamond extending around the periphery of the compact to reduce the residual stresses inherent in thick diamond regions of cutters. This compact has improved wear and durability characteristics because it avoids failures due to stresses, delaminations and fractures caused by the differences in thermal expansion coefficient between the diamond and the substrate during sintering. Moreover, this invention may provide multiple polycrystalline diamond edges as the PDC wears. This exposure of multiple polycrystalline diamond edges slows the rate of wear flat surface development and reduces the weight on the bit required for acceptable drill penetration rates.

Abstract: A cutting structure for a rotary drag-type drill bit includes a cutting element mounted on a member on the bit body, which may be a carrier secured to the bit body or part of the bit body itself. The surface of the member on which the cutting element is mounted is formed with a groove, adjacent the cutting element. The downstream end of the groove is located near a nozzle in the bit body through which a jet of drilling fluid emerges, so that the groove directs to the front of the cutting element the flow of drilling fluid which impinges on the groove. An array of separate grooves may lead from the nozzle to different cutting elements. The flow of drilling fluid directed towards each cutting element serves to break up cuttings removed from the formation by the cutting element and to carry the cuttings away from the element.

Abstract: A cutter element for a drill bit. The cutter element has a non-rectilinear crest. The non-rectilinear or curvilinear crest provides an advantageous distribution of the cutting forces across the body of the cutter elements and thus improves bit life. The curvilinear crest also allows the cutter element to more efficiently lift the portion of the formation that is being cut, thereby improving cutting action in certain formations. The cutter elements can have either positive or non-positive draft and can be tungsten carbide inserts.

Abstract: A supporting substrate for supporting a diamond layer on a cutting element is disclosed which has an irregular surface defining the interface between the substrate and the diamond layer. The irregularities in the surface may have varying amplitudes, varying frequencies, or both and can vary according to defined mathematical expressions. The irregularities may assume recognizable geometric forms, such as spiral, circle or wave configurations, or may be arranged in an irregular manner. The surface is constructed with or without a plane of symmetry and may have different average amplitudes and/or frequencies in different areas.

Abstract: A wear resistant cutter insert structure and method include a stud having at least one face. A primary tapered ridge and at least one secondary tapered ridge extending from the primary tapered ridge are formed in the face. A layer of abrasive material is disposed over the face covering the primary and secondary tapered ridges.

Abstract: An earth-boring bit has a bit body and at least one cantilevered bearing shaft depending inwardly and downwardly from the bit body. A cutter is mounted for rotation on the bearing shaft and includes a plurality of cutting elements. At least one of the cutting elements has a generally cylindrical body formed of hard metal with a convex cutting end. A plurality of recesses extend longitudinally from the apex to the junction. The recesses are shallow grooves symmetrically spaced about the axis. A layer of super-hard material is formed on the cutting end of the body and overlays the recesses formed thereon.

Abstract: The present invention relates to a cutting insert for a rock drill bit. The rock drill bit includes a tool body (10) having a front surface (13), and a number of cutting inserts (14), each having a generally cylindrical shank portion. The cutting insert (14) is provided with increased volume portions in its parts being most subjected to wear. The invention also relates to the rock drill bit.

Abstract: An earth-boring bit has a bit body with at least one bearing shaft depending inwardly and downwardly therefrom. A cutter is mounted for rotation on each bearing shaft and has a cutter shell surface and a plurality of cutting elements arranged on the shell surface in generally circumferential rows. A pair of surfaces extends from the cutter shell surface on opposing sides of one of the circumferential rows of cutting elements. The pair of surfaces converge together to define a kerf crest that is oriented transversely to the axis of rotation of the cutter. The kerf crest projects from the cutter shell surface by an amount less than the cutting elements in the kerf row having the kerf crest.

Abstract: A cutting element is composed of a metal carbide stud having an outer hemispherical distal end which has a series of annular ridges. The tops of the annual ridges are substantially non-planar, i.e., curvilinear, such that the angle formed between the slope on either side is less than 120.degree.. There are no surfaces tangent to vertical on such ridges. A layer of polycrystalline superabrasive material is disposed over the annular ridges. This cutter is easily manufacturable as the metal stud can be pressed and extracted from the punch without further machining and the surface geometry of the metal stud allows for complete PCD compaction during diamond sintering.

Abstract: An earth-boring bit has a bit body and at least one cantilevered bearing shaft depending inwardly and downwardly from the bit body. A cutter is mounted for rotation on the bearing shaft and includes a plurality of cutting elements. At least one of the cutting elements has a generally cylindrical body formed of hard metal with a convex cutting end. A plurality of substantially recesses are formed on the cutting end of the body. The recesses are configured such that a line parallel to the longitudinal axis of the body may extend from any point of each of the recess without touching any other point on the same recess. This enables the cutting element body and the recess to be formed simultaneously by conventional powder metallurgical techniques. A layer of super-hard material is formed on the cutting end of the body and overlays the recesses formed thereon.

Abstract: A preform cutting element, for a rotary drag-type drill bit, includes a facing table of superhard material having a front face, a peripheral surface, and a rear surface bonded to the front surface of a substrate which is less hard than the superhard material. The facing table extends across only a part of the front surface of the substrate, and part of the substrate engages the peripheral surface of the facing table. When such a cutting element is mounted on a bit body with the part of the facing table periphery which is engaged by the substrate being located opposite the cutting edge of the element, the part of the substrate which engages the periphery of the facing table acts as a mechanical support to the facing table so as to resist impact and other loads to which the facing table may be subject in use.

Abstract: A rolling cutter drill bit and method for making a rolling cutter drill bit having a cutting insert pressed into a socket, wherein the socket forms a juncture with the curved outer surface of a rolling cutter, and the juncture contacts a plane in contact with the juncture in at least three points located on the juncture.

Abstract: A preform element, such as a preform cutting element for a rotary drag-type drill bit, includes a facing table of polycrystalline diamond having a front face, a peripheral surface, and a rear surface bonded to the front surface of a tungsten carbide substrate. The front surface of the substrate is formed with a plurality of recesses into which extend corresponding projections formed on the rear surface of the facing table. The recesses include at least one rebate which extends around only a part of the periphery of the substrate and into which extends a projection on the facing table which provides a part of the peripheral surface of the facing table.

Abstract: Polycrystalline diamond cutter (PDC) designs which substantially improve the penetration rate of fixed cutter drill bits while simultaneously reducing the wear on the bit during drilling operations are disclosed. The designs are based upon the observation that: 1) the wear pattern of a PDC is roughly a conic section and is parallel to bit rotation, and 2) the cutting surface is perpendicular to the rotation of the bit. The inventive PDC designs provide cutting action both perpendicular and parallel to the direction of bit rotation.