Abstract: A method for forming an ultra hard material layer is provided. The method includes disposing a metallic liner inside the periphery of a refractory metal enclosure, introducing ultra hard material feed stock into the enclosure, and sintering using HPHT processing and cooling to form the ultra hard material layer, substantially free of peripheral cracking, chipping and fracturing.

Abstract: An earth-boring bit has a bit body that includes head sections, each having depending bit legs with a circumferentially extending outer surface, a leading side, and a trailing side. A bearing shaft depends inwardly from each of the bit legs for mounting a cutter. The bit includes a beveled surface formed at a junction of the leading side and the outer surface of each bit leg. The beveled surface is angled relative to a radial plane emenating from the axis of the bit. The angle of the beveled surface is at least 20 degrees, and extends to an inner surface of the bit leg. The bit can also have a layer of hardfacing on the leading, trailing and shirttail surfaces of the bit leg. A diversion finger of hardfacing extends circumferentially to direct cuttings.

Abstract: An insert for a drill bit that includes diamond particles disposed in a matrix material, wherein the diamond particles have a contiguity of 15% or less is disclosed. A method of forming a diamond-impregnated cutting structure, that includes loading a plurality of substantially uniformly coated diamond particles into a mold cavity, pre-compacting the substantially uniformly coated diamond particles using a cold-press cycle, and heating the compacted, substantially uniformly coated diamond particles with a matrix material to form the diamond impregnated cutting structure is also disclosed.

Abstract: Cutting elements of this invention include an ultra hard body joined with a metallic substrate. The body includes an uppermost layer comprising a plurality of bonded ultra hard crystals and interstitial regions, and that defines a body working surface. The uppermost layer includes an outer region that is relatively more thermally stable than a remaining portion of the uppermost layer. The body further includes an intermediate layer joined to the uppermost layer, comprising a plurality of bonded ultra hard crystals, and having a wear resistance less than that of the uppermost layer remaining region. The body may additionally include a lowermost PCD layer that is interposed between and attached to the intermediate layer and the substrate.

Abstract: An earth-boring bit has a body with three bit legs. A cone is rotatably mounted to each of the bit legs. Each of the cones has an outer row and an inner row of teeth machined on it. Each of the teeth has a rectangular root with inner, outer and lateral boundaries. A layer of hardfacing is applied to each tooth and on an exterior portion of each of the cones surrounding the inner, outer and lateral boundaries of each of the teeth. Conical surfaces between the inner and outer rows contain at least portions of the hardfacing.

Abstract: A drill bit includes a plurality of cutting elements are positioned on the at least two roller cones, wherein cutting elements contributing to an operative gage row of the drill bit comprise less than 31 percent of a total cutting elements of the drill bit that contact the bottom of the borehole. A method to design a roller cone drill bit includes designing an initial bit, testing the initial bit; and adjusting the bit design to optimize at least one of rate of penetration and wear resistance, wherein cutting elements contributing to an operative gage row of the adjusted bit design comprise less than 31 percent of a total of cutting elements on the adjusted bit design that contact a bottom of a borehole.

Abstract: A rolling cone rock bit includes a plurality of PDC or other cutters mounted to the leg of the drill bit and positioned to cut the corner of the bottomhole. The plurality of cutters may be the primary cutting component at gage diameter, or may be redundant to gage teeth on a rolling cutter that cut to gage diameter. Consequently, the occurrence of undergage drilling from the wear and failure of the gage row on a rolling cutter is lessened. Also included is a mud ramp that creates a large junk slot from the borehole bottom up the drill bit. The resulting pumping action of the drill bit ramp speeds up the removal of chips or drilling cuttings from the bottom of the borehole, reduces the level of hydrostatic pressure at the bottom of the borehole and minimizes the wearing effect of cone inserts regrinding damaging drill cuttings.

Abstract: Roller cone drill bits are provided with cutting elements and cutting structures optimized for efficient drilling of soft and medium formations interspersed with hard stringers. The cutting elements and cutting structures may be satisfactorily used to drill downhole formations with varying amounts of hardness. The cutting elements and cutting structures may also be optimized to reduce tracking and increase wear resistance.

Abstract: An earth-boring bit has a steel body and bearing pin for rotatably supporting a cone. The cone has an exterior surface containing rows of cutting elements. The cone and cutting elements are formed of cemented tungsten carbide. The cone may be manufactured by applying pressure to a mixture of hard particles and metal alloy powder to form a billet, then machining the billet to a desired over-sized conical shaped product. Then the conical-shaped product is liquid-phase sintered to a desired density, which causes shrinking to the desired final shape.

Abstract: A downhole abrading tools has a body with a first end for connection with a rotating component of a drill string, and a cutting end for rotation in unison with the body, the cutting end having an abrading matrix containing an abrasive material for rotating engagement with an object within the well. The downhole abrading tool also includes a passage through the tool for circulating a drilling fluid. The abrading matrix includes at least one taggant embedded within the abrading matrix capable of being released by the abrading matrix into the downhole location due to wear on the abrasive material and transported to the surface location along with the drilling fluid for detection. When the taggant is released due to excessive wear, the taggant is carried from the downhole location in the well to the surface of the well where it can be detected by the operator of the tool.

Abstract: An earth-boring bit has a body with three bit legs. A cone is rotatably mounted to each of the bit legs. Each of the cones has an outer row and an inner row of teeth machined on it. Each of the teeth has a rectangular root with inner, outer and lateral boundaries. A layer of hardfacing is applied to each tooth and on an exterior portion of each of the cones surrounding the inner, outer and lateral boundaries of each of the teeth. Conical surfaces between the inner and outer rows contain at least portions of the hardfacing.

Abstract: A hardfacing composition for a drill bit includes a carbide phase made from carbide particles having a barrier coating disposed thereon, and binder alloy. Also, a drill bit includes a steel bit body having hardfacing thereon and having at least one blade thereon, at least one cutter pocket disposed on the blade, at least one cutter disposed in the cutter pocket; and hardfacing applied to at least composition that includes a carbide phase formed from carbide particles having a barrier coating disposed thereon; and a binder alloy.

Abstract: An earth boring bit has cutting elements arranged to avoid tracking. The bit has a bit body having a bit axis of rotation. First, second and third cones are rotatably mounted to the bit body, each of the cones having a plurality of rows of cutting elements including a heel row and an adjacent row. The heel row of the first cone has at least equal the number of cutting elements as the heel rows of the other cones. The adjacent row of the second cone has at least 90 percent as many cutting elements as the heel row of the first cone. The heel row of the third cone has a pitch that is in the range from 20-50% greater than the heel rows of the first cone.

Abstract: A seal assembly for an earth boring bit uses a magnet to provide a desired contact force. The seal is located between a rotating cone and a stationary bearing pin of the drill bit. The seal has a non rotating metal face that is in sliding engagement with a seal face in the cone that rotates with the cone. The non rotating seal face is provided by a carrier ring that encircles the bearing pin. A magnet is mounted to the carrier ring to provide an attraction force maintaining the carrier ring in contact with the rotating seal face in the cone. An elastomeric seal ring seals between the carrier ring and the bearing pin to prevent rotation of the carrier ring.

Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.

Abstract: A new composition for forming a matrix body which includes spherical sintered tungsten carbide and an infiltration binder including one or more metals or alloys is disclosed. In some embodiments, the composition may include a Group VIIIB metal selected from one of Ni, Co, Fe, and alloys thereof. Moreover, the composition may also include cast tungsten carbide. In addition, the composition may also include carburized tungsten carbide.

Abstract: An earth boring bit has at least one rotatable cone with a gage surface that engages a sidewall of a wellbore as the bit rotates. The gage surface has hardfacing bars spaced circumferentially apart from each other. A first group of the hardfacing bars extends from the inner edge of the gage surface to gage sides of the heel row cutting elements. A second group of the hardfacing bars extends from the inner edge of the gage surface to spaces between the heel row cutting elements, forming trimmer cutting elements. The hardfacing bars are made up of carbide particles in a metallic matrix.

Abstract: A method for designing a roller cone drill bit having a plurality of cutting elements in a row. The method includes defining a pitch pattern for the plurality of cutting elements such that a first group of adjacent cutting elements are arranged in a first pitch and a second group of adjacent cutting elements are arranged in a second pitch in the row; evaluating the pitch pattern of the plurality of cutting elements in the row; and modifying at least one of the plurality of cutting elements, based on the evaluating the pitch pattern of the plurality of cutting elements.

Abstract: An earth boring drill bit is constructed having rotatable cutter for forming a borehole in earth. At least one circumferential row of cutting elements is optimized to create overbreak of rock and eliminate tracking, wherein selected pitches have mathematically determined pairs and the absolute difference between the selected pitch and its pair is greater than 10% of the difference between maximum and minimum pitch for that circumferential row. Furthermore, cutting elements are placed along pre-selected generatrices with deviation from said generatrices, which is less than half the maximum pitch of circumferential rows occupied by said cutting element. The present invention eliminates tracking and reduces detrimental axial resonance frequency vibration while reducing cutting element count, including tungsten-carbide inserts, as compared to conventional roller cutter drill bits used for oil, gas and shot hole drilling wells and simultaneously increases footage drilled, drilling speed, and durability.

Abstract: An earth-boring bit has a bit body that includes head sections, each having depending bit legs with a circumferentially extending outer surface, a leading side, and a trailing side. A bearing shaft depends inwardly from each of the bit legs for mounting a cutter. The bit includes a beveled surface formed at a junction of the leading side and the outer surface of each bit leg. The beveled surface is angled relative to a radial plane emenating from the axis of the bit. The angle of the beveled surface is at least 20 degrees, and extends to an inner surface of the bit leg. The bit can also have a layer of hardfacing on the leading, trailing and shirttail surfaces of the bit leg. A diversion finger of hardfacing extends circumferentially to direct cuttings.

Abstract: A rolling cone drill bit is provided that has gage inserts on the first row from the bit axis to cut to full gage diameter that have a cutting portion enhanced with a layer of super abrasive material. The gage cutting surface has a center axis that is canted to be more normal to the gave curve such that its point of contact at gage is away from the thinner portion of the layer of super abrasive material.

Abstract: A roller cone drill bit includes a bit body adapted to be coupled to a drill string, at ne leg depending from the bit body, and a bearing journal on the at least one leg, wherein least one leg defines a shirttail portion at an end thereof. A method of manufacturing the cone drill bit includes assembling a roller cone onto the bearing journal on the at least one asking around the shirttail portion, and performing a spray cycle. The spray cycle includes ng the shirttail portion with hardfacing using a high pressure/high velocity oxygen fuel after the roller cone is assembled onto the bearing journal.

Abstract: A drill bit that includes a bit body, at least one roller cone attached to the bit body and able to rotate with respect to the bit body, a plurality of cutting elements disposed on the at least one roller cone, and a barrel axis is disclosed. At least one of the plurality of cutting elements includes a first area defining a secondary wear surface, wherein the first area is formed as a convex surface on the trailing edge, a second area proximate the first area defining a main wear surface, wherein the second area is formed as a convex curved surface having a radius of curvature substantially equal to a radius of a borehole, and a third area defining a spherical cutting surface. Further, at least one of the plurality of cutting elements includes a non-spherical transition zone disposed between the third area and the first and second areas, wherein the barrel axis intersects the transition zone.

Abstract: Disclosed is a rolling cone cutter and drill bit employing multiple inserts retained as a cluster in an aperture in the cone cutter. Apertures in which the insert clusters are retained are multilobed apertures formed by intersecting bores formed in the cone steel. The apertures may also be created by forming spaced apart bores and milling regions of the cone steel that extends between the bores. The inserts in a cluster may be retained within the aperture to differing depths, may extend above the cone steel to differing extension lengths, and may have cutting portions having a variety of shapes. The inserts in a cluster may be made of different materials in order to optimize cutting duty.

Abstract: An insert for a rock bit that includes tungsten carbide particles, and a cobalt binder disposed around the particles, wherein a grain size of the tungsten carbide particles and a content of the cobalt binder are selected to provide a fracture toughness of at least about 18 ksi (in)0.5, a wear number of at least about 2, and a hardness of 85 to 87 Ra is disclosed.

Abstract: A method of forming a tooth rock bit is disclosed. In one embodiment, the method includes attaching the at least one cutting element to a surface of a cone, and depositing a hard facing layer on at least one cutting element prior to the attaching.

Abstract: Cutting elements having coarse grain substrates and ultra hard material layers are provided. The substrates are formed from coarse grain size particles of tungsten carbide. A method of forming such cutting elements and a drag bit incorporating such cutting elements are also provided.

Abstract: An earth boring bit has rolling cones rotatably mounted to the bit legs. Each cone has conical bands extending around the exterior. Holes are formed in each of the bands. Compacts are press-fitted into the holes, each having a cutting tip that projects from the conical band. Flats are formed in the conical bands, each flat extending between adjacent compacts.

Abstract: A drill bit for use in earth-boring operations includes a threaded upper section removably connectable to a power source, and a shank section connected thereto and having a centrally disposed longitudinal axis. The shank section further has a lower portion extending substantially vertically and parallel to the axis and a plurality of notches spaced along a perimeter thereof. The present invention further includes a plurality of carbide buttons affixed to the plurality of notches respectively for cooperating with a plurality of cones during operating conditions to thereby prevent the plurality of cones from dislodging from the lower section and for assisting an operator to bore a substantially uniform hole in a predetermined direction and about the longitudinal axis.

Abstract: A rolling cone drill bit is provided that has gage inserts on the first row from the bit axis to cut to full gage diameter that have a cutting portion enhanced with a layer of super abrasive material. The gage cutting surface has a center axis that is canted to be more normal to the gage curve such that the its point of contact at gage is away from the thinner portion of the layer of super abrasive material.

Abstract: A method is disclosed for applying hardfacing to a shirttail portion of a roller cone drill bit, including masking around the shirttail portion of the bit and operating a high pressure/high velocity oxygen fuel torch to apply the hardfacing to the shirttail portion.

Abstract: PCD materials of this invention comprise diamond crystals that are bonded together with a catalyst/binder material. The PCD material is prepared by combining diamond grains with a catalyst/binder material either as a premixture or by infiltration during sintering. The PCD material comprises 15 percent by volume or less diamond grains sized 20 micrometers or less. The diamond grains are pressurized under elevated temperature conditions to form the desired PCD material. PCD materials of this invention can constitute the exclusive material phase of a PCD construction, or can form one or more material phase in a multi-phase material microstructure, wherein the multiple material phase can be arranged in an ordered/oriented or random fashion. PCD materials of this invention display improved properties of impact and fatigue resistance, and functional toughness, when used in complex wear environments, when compared to conventional PCs materials comprising intentionally added fine-sized diamond grains.

Abstract: A rotary-cutter Earth-penetrating bit in which a given track of bottom hole is attacked by inserts of two different types, e.g. chisel-shaped and pointed, wider and narrower, higher and shorter, and/or of different materials. The different types of inserts can both be included within a single row of a cone.

Abstract: An earth-boring bit has a bit body, at least one cantilevered bearing shaft depending inwardly and downwardly from the bit body, and a cutter mounted for rotation on the bearing shaft. The cutter includes a plurality of teeth that are covered with a hardfacing layer. At least some of the teeth have a leading side that has a streamlined contour. The streamlined contour is generally conical in some of the embodiments. In others, the streamlined contour is defined by a corner between diverging inner and outer sections of the leading side.

Abstract: A cutting element and bit incorporating the cutting element is provided, as well as a method for forming the same. The cutting element includes an ultra hard material layer including chromium and carbon and exhibiting increased abrasion resistance without sacrificing toughness. The method for manufacturing the cutting element includes providing a layer of ultra hard material particles and chromium carbide over the substrate, and then sintering to form the cutting element.

Abstract: A bit body formed of a mixture of matrix material and superabrasive powder and including pockets lined with superabrasive-free matrix material, and a method for forming the same, are provided. The pockets are shaped to receive cutting elements therein. The superabrasive-free matrix material enhances braze strength when a cutting element is brazed to surfaces of the pocket. The method for forming the drill bit body includes providing a mold and displacements. The displacements are coated with a mixture of superabrasive free matrix-material and an organic binder. The mold is packed with a mixture of matrix material and superabrasive powder and the arrangement heated to form a solid drill bit body. When the solid bit body is removed from the mold, pockets are formed by the displacements in the bit body and are lined with the layer of superabrasive-free matrix material. The superabrasive material may be diamond, polycrystalline cubic boron nitride, SiC or TiB2 in exemplary embodiments.

Abstract: A method for optimizing drilling performance of a roller cone drill bit is disclosed. The method includes simulating drilling with the bit in a selected earth formation to determine at least one drilling performance parameter. The orientation of at least one non-axisymmetric cutting element on the bit is adjusted and the simulating the drilling and determining the at least one performance parameter are repeated. The adjusting and simulating the drilling are repeated until the at least one performance parameter is determined to be at an optimum value. In one embodiment, the performance parameter includes rate of penetration.

Abstract: Disclosed are a variety of arcuate-shaped inserts for drill bits, and in particular, for placement in rolling cone cutters of drill bits. The arcuate inserts include 360 degree or ring-shaped inserts, as well as inserts of smaller arcuate length. The arcuate inserts may include stress relieving discontinuities such that, upon assembly into the cone, the arcuate inserts fragment in a controlled and predicted manner into shorter arcuate lengths. The arcuate inserts are suitable for use in all surfaces of the rolling cone cutter, and in other locations in drill bits, and may have specialized cutting surfaces and material enhancements to enhance their cutting duty performance.

Abstract: A variety of large diameter PDC cutters for use in drill bits are disclosed. Specifically, various PDC cutters having a diameter between 19.0 mm and 25.0 mm are disclosed. The various PDC cutters disclosed include an elliptical PDC cutter, wherein a major diameter of the elliptical cutter is selected from a range of 19.0 mm to 25.0 mm, a circular PDC cutter, wherein a diameter of the circular cutter falls between 19.0 mm and 25.0 mm, and a non-planar substrate cutter, wherein a diameter of the non-planar cutter falls between 19.0 mm and 25.0 mm. Additionally, the thickness of the diamond table is increased as compared to prior art PDC cutters. The increase in diamond table thickness results in improved durability and performance.

Abstract: Roller cone drilling wherein the bit optimization process equalizes the downforce (axial force) for the cones (as nearly as possible, subject to other design constraints). Bit performance is significantly enhanced by equalizing downforce.

Abstract: Disclosed is a rolling cone cutter and drill bit employing multiple inserts retained as a cluster in an aperture in the cone cutter. Apertures in which the insert clusters are retained are multilobed apertures formed by intersecting bores formed in the cone steel. The apertures may also be created by forming spaced apart bores and milling regions of the cone steel that extends between the bores. The inserts in a cluster may be retained within the aperture to differing depths, may extend above the cone steel to differing extension lengths, and may have cutting portions having a variety of shapes. The inserts in a cluster may be made of different materials in order to optimize cutting duty.

Abstract: A cutter for a tunnel boring machine is equipped with a cutter body (1) with a slanting surface (2), a cylindrical contact surface (12) and a preferably tapered threaded portion with specially designed threads (6), a clamping ring (4) with threads adapted to the cutter body's threads with a slanting surface (5) with a groove (13) with a spring (14). The cutter has an undivided (3) or divided cutter ring (with segments 3a, 3b) with a cross section with slanting lateral surfaces (7, 8) in the foot and a cylindrical contact surface (11). The diameter of the cutter ring's cylindrical contact surface (11) has a clearance tolerance relative to the diameter of the cylindrical contact surface (12) of the cutter body.

Abstract: In one embodiment, a hardfacing composition for a drill bit, including a carbide phase including from about 50% to about 80% by weight of the hardfacing composition of a combination of 80 to 200 mesh macro-crystalline tungsten carbide and 80 to 200 mesh crushed cast carbide, the crushed cast carbide being about 5% to 50% of the total weight of the carbide phase, and a binder alloy comprising about 20% to about 50% by weight of the hardfacing composition is disclosed. A hardfacing composition for a drill bit, including a carbide phase composed of sintered tungsten carbide having a particle size from about 80 to 200 mesh that is about 50% to about 80% by weight of the hardfacing composition, and a binder alloy forming about 20% to about 50% by weight of the hardfacing composition.

Abstract: Cutter elements for use in rolling cones rock bits are disclosed having a crown that includes multiple, spaced-apart cusps for enhancing formation removal by creating overlapping Hertzian contact zones. The cusps may be partially dome-shaped, berm shaped or otherwise. The cutter elements provide multiple cutting edges for engaging the formation and may have differing radii and extension length as suitable for particular applications.

Abstract: A method is disclosed for applying hardfacing to a shirttail portion of a roller cone drill bit, including masking around the shirttail portion of the bit and operating a high pressure/high velocity oxygen fuel torch to apply the hardfacing to the shirttail portion.

Abstract: An earth-boring bit has a bit body, at least one cantilevered bearing shaft depending inwardly and downwardly from the bit body, and a cutter mounted for rotation on the bearing shaft. The cutter includes a plurality of teeth that are covered with a hardfacing layer. At least some of the teeth have a leading side that has a streamlined contour. The streamlined contour is generally conical in some of the embodiments. In others, the streamlined contour is defined by a corner between diverging inner and outer sections of the leading side.

Abstract: In one embodiment, a method of increasing a durability of a drill bit having a bit body with at least one blade disposed thereon, at least one cutter pocket disposed on the blade, and at least one cutter disposed in the cutter pocket is disclosed. The method includes brazing the at least one cutter to the at least one cutter pocket so that a braze material disposed between the at least one cutter pocket and the at least one cutter comprises an exposed surface, and overlaying at least a portion of the exposed surface with a hardfacing material, wherein the hardfacing material includes a binder having a melting point selected to avoid damaging the cutter.

Abstract: Drill bit reinforcing members or blanks of this invention are formed from high-strength steels having a carbon content less than about 0.3 percent by weight, a yield strength of at least 55,000 psi, a tensile strength of at least 80,000 psi, a toughness of at least 40 CVN-L, Ft-lb, and a rate of expansion percentage change less than about 0.0025%/° F. during austenitic to ferritic phase transformation. In one embodiment, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.5 to 1.5 percent by weight manganese, up to about 0.8 percent by weight chromium, 0.05 to 4 percent by weight nickel, and 0.02 to 0.8 percent by weight molybdenum. In another example, such steel comprises in the range of from about 0.1 to 0.3 percent by weight carbon, 0.9 to 1.5 percent by weight manganese, 0.1 to 0.5 percent by weight silicon, and one or more microalloying element selected from the group consisting of vanadium, niobium, titanium, zirconium, aluminum and mixtures thereof.

Abstract: A hardfacing material is applied to cutting elements formed on the surface of cutters of an earth-boring bit. The hardfacing material forms the outer surface of the teeth, and also substantially forms scrapers on the shell of each of the cutters. The adding of the hardfacing material to the outer surface of the teeth and the forming of the scrapers is accomplished through welding. The hardfacing material is machined from its “as-welded” state to have a smoother surface finish.

Abstract: A drill bit that includes a bit body, at least one roller cone attached to the bit body and able to rotate with respect to the bit body, and a plurality of cutting elements disposed on the at least one roller cone is disclosed. At least one of the plurality of cutting elements includes a first area defining a trailing edge, and a second area proximate the first area defining a main wear surface.. Further, an insert for a drill bit that includes a contact portion adapted to contact an earth formation, the contact portion including a first area defining a relieved trailing edge, and a second area defining a main wear surface, wherein a surface of the second area is a curved surface having a radius of curvature substantially equal to a radius of a borehole is also disclosed.