Abstract: The present invention provides a method of making an earth boring drill bit having a superhard polycrystalline diamond or diamond-like element with greatly improved resistance to thermal degradation without loss of impact strength. Collectively called PCD elements, these elements are formed with a binder-catalyzing material in a high-temperature, high-pressure process. The PCD element has a plurality of partially bonded diamond or diamond-like crystals forming at least one continuous diamond matrix, and the interstices among the diamond crystals forming at least one continuous interstitial matrix containing a catalyzing material. The element has a working surface and a body, where a portion of the interstitial matrix in the body adjacent to the working surface is substantially free of the catalyzing material, and the remaining interstitial matrix contains the catalyzing material.

Abstract: A drill bit comprising a bit body, at least one roller cone rotatably mounted on the bit body. The cone has a plurality of milled teeth at selected locations on the cone. At least one of the milled teeth comprises a substrate having a convex crest and a layer of hardfacing applied to said convex crest. The convex crest is adapted to produce at least one of a convex axial stress distribution, a substantially even axial stress distribution, and a substantially smooth axial stress distribution.

Abstract: A rotary drag bit carrying PDC cutters and elongated bearing elements associated with at least some of the PDC cutters on the bit face. Lateral positioning and angular positioning of the elongated bearing elements are adjusted so that all portions of a elongated bearing element travel substantially completely within a tubular clearance volume defined by the path through the formation being drilled by a PDC cutter with which that elongated bearing element is associated, the associated PDC cutter being positioned at about the same radius from the bit centerline as the elongated bearing element. A method of drilling and a method of drill bit design are also disclosed.

Abstract: A cutting element for a drill bit used in drilling subterranean formations is formed with an internal chamber or passage for the flow of drilling fluid therethrough. A substrate having at least one internal passage, and prior to attaching the table thereto, the at least one passage is filled with a removable substantially incompressible filler material. Attachment or bonding of the table to the substrate under high temperature and high pressure is accomplished without significant distortion of the shape and size of the passage. The filler material may be a crystalline salt such as sodium chloride or halite, which are removable by dissolution in water, or may be boron nitride or a volcanic material such as Pyrofolyte material which are mechanically removable.

Abstract: Rock bits comprising wear and fracture resistant surface of this invention include a steel bit body having at least one leg extending therefrom. A steel cone is rotatably disposed on the leg. The steel cone includes a plurality of steel cutting elements that each projecting outwardly a distance therefrom. At least a portion of the cone comprises a wear resistant surface formed from a wear resistant composite material. The wear resistant composite material is made by the process of combining powders selected from the group consisting of carbides, borides, nitrides, carbonitrides, refractory metals, cermets, Co, Fe, Ni, steel, and combinations thereof, to form a material mixture. The material mixture is applied onto a designated surface of the cone, in one form or another, when the cone is in a pre-existing rigid state. Depending on the particular application, the material mixture can be applied in as a slurry to the designated surface of the cone to form a coating thereon.

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: A rotary-type earth-boring drill bit including a layer-manufactured, substantially hollow bit crown and an integral bit interior and bit gage. The bit interior and bit gage may be formed of a particulate material infiltrated with an infiltrant material. A particulate material of the bit crown may be integrally infiltrated with the particulate material of the bit interior and bit gage. Alternatively, the bit interior and bit gage may comprise a single cast material. The particulate material of the bit crown may be infiltrated with the cast material of the bit interior and bit gage. A method of fabricating the drill bit includes employing known layered-manufacturing techniques to fabricate the bit crown, positioning a bit gage mold adjacent the bit crown, and disposing a core material within an interior of the bit crown and a cavity of the bit gage mold.

Abstract: A rotary-type drill bit for drilling subterranean formations having areas or components having surfaces exhibiting a relatively low adhesion, preferably nonwater-wettable, surface over at least a portion thereof.

Abstract: An earth-boring bit comprises a bit body bit body in which are mounted a plurality of cutting structures inserts, wherein at least a portion of the cutting structures comprise diamond-impregnated inserts having a total thermal exposure of less than 25 minutes above 1500° F. The diamonds can be natural or synthetic diamond. The bit body itself may be diamond-impregnated, in which case it is preferred that the diamonds in the inserts make up at least 40% of the total diamond in the bit.

Abstract: A cutting element having a cutting table made from sheet segments of commingled ultra hard material and binder. Each segment may be made from a finer or a coarser grade of ultra hard material or from different types of ultra hard material. The segments are aligned side by side over a cutting face of the cutting element to form the cutting table. The material grade and/or the material type of each segment may alternate across the cutting face.

Abstract: A method for use in designing rotary drill bits comprises determining locations in which cutters are to be provided, determining likely wear rates for cutters positioned at those locations, and using the likely wear rates to chose between relatively high and relatively low wear rate cutters for each location. The cutters all have substantially the same impact toughness.

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: The present invention is a drag-type drill bit for drilling a borehole in the earth. The bit is designed to rotate about a central axis of rotation and has a bit body having a leading face, an end face, a gauge region, and a shank for connection to a drill string, a plurality of nozzles in the bit body for delivering drilling fluid to the end face, a plurality of blades upstanding from the leading face of the bit body and extending outwardly away from the central axis of rotation of the bit. Each blade terminates in a gauge pad with a surface which faces a wall of the borehole. A first plurality of cutters are mounted on the blades at the end face of the bit body and a second plurality of cutters are mounted the gauge pads and arranged such that in operation, they cut the wall of the borehole. Each one of the second plurality of cutters has a backrake less than or equal to about 20 degrees.

Abstract: The invention is a drill bit that has 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. At least one bit design parameter is selected so that the cutting elements wear in a selected manner when drilling an earth formation.

Abstract: Although particular detailed embodiments of the apparatus and method have been described herein, it should be understood that the invention is not restricted to the details of the preferred embodiment. Many changes in design, composition, configuration and dimensions are possible without departing from the spirit and scope of the instant invention.

Abstract: A rotary cone drill bit is provided with at least one cutter cone assembly having a machined cutting structure which will maintain an effective cutting profile despite abrasion, erosion and/or wear of the associated cutting elements. The machined cutting structure may be formed on a generally cone shaped blank by a series of lathe turns and/or plunge cuts. The cutting elements may be formed with an aggressive cutting profile. For one application, the crest of each cutting element has the general configuration of an ogee curve. A layer of hardfacing material may be applied over all or selected portions of the machined cutting structure.

Abstract: A wear resistant drill bit of the matrix bodied type has a bit body comprising a tungsten carbide material bound with a binder material, wherein the tungsten carbide material includes at least some tungsten carbide particles of generally spherical shape. The tungsten carbide material includes particles having a relatively hard central core and a softer skin. The skin includes a large proportion of a high temperature phase of tungsten carbide.

Abstract: A novel and improved roller cone drill bit and method of design are disclosed. A roller cone drill bit for drilling through subterranean formations having an upper connection for attachment to a drill string, and a plurality cutting structures rotatably mounted on arms extending downward from the connection. A number of teeth are located in generally concentric rows on each cutting structure. The actual trajectory by which the teeth engage the formation is mathematically determined. A straight-line trajectory is calculated based on the actual trajectory. The teeth are positioned in the cutting structures such each tooth having a designed engagement surface is oriented perpendicular to the calculated straight-line trajectory.

Abstract: A method to design a bi-center drill bit designed to drill out the cement and other material in the casing and then proceed to drill out the full gauge drilling diameter borehole with a diameter greater than the inside of the casing. The bi-center drill bit has a pilot section on the end of the bit body, an eccentric reamer section and a plurality of cutting elements on the pilot section. The design method comprises the steps of: defining a first center of rotation of the pilot section about the longitudinal axis, defining a radius of rotation R1 of the drill bit about the first center of rotation, defining a second center of rotation of the pilot section spaced apart from the first center of rotation by a distance D, defining a radius of rotation R2 of the drill bit about the second center of rotation, and setting the relationship between D, R1 and R2 such that R1 is less than the sum of R2 and D.

Abstract: A roller cone drill bit in which the orientations of the teeth are varied within a single row, and/or between the heel row of one cone and the heel row of another cone, to prevent tracking.

Abstract: A rotary-type earth-boring drag bit with cutters oriented at varied rake angles. Specifically, cutters that are located sequentially adjacent radial distances from a longitudinal axis of the drill bit have cutting faces that are oriented at rake angles that differ from one another. These cutters may be located on the same blade of the drag bit or on different blades of the drag bit. The rake angles at which the cutting faces of these cutters are oriented may be based, at least in part, on the relative radial distances these cutters are spaced from the longitudinal axis of the drag bit, on the vertical positions of these cutters along the longitudinal axis of the drag bit, or in response to actual or simulated evaluations of the use of drag bit to drill a subterranean formation. Methods for designing drag bits are also disclosed.

Abstract: A deburring tool for performing non-abrasive deburring of metal and other hard-material parts subject to burring. The deburring tool comprises a portion shaped to engage a specific surface on a workpiece, and surfaced with a deburring material comprising the soft, fuzzy, female loop half of ordinary hook and loop fastener. The female loop half of the hook and loop fastening material is non-abrasive, yet is extremely effective at removing small burrs and shavings from metal parts. In a preferred form, the deburring tool forms a two-sided deburring channel or track through which a part such as a hose connector block having a recessed surface needing deburring can be swiped. Both sides of the channel are surfaced with the female loop half of the hook and loop fastener as the deburring medium.

Abstract: The invention is embodied in an earth boring tool comprising a bit body having a rotatable working head portion with a cutter element having a wear table of superhard material bonded to a substrate, and wherein the superhard and substrate materials have different coefficient properties creating a stress condition at their interface during bonding and wherein the cutter elements are stress relieved in situ on the bit body by low temperature heat annealing for a preselected time, and in which the cutter elements and bit body head portion are constructed and arranged for heat management in a dry, vacuum drilling operation. The invention further involves the heat management system and method of the stress relief process of heat annealing PCD cutter elements in situ, either alone or with a subsequent cryogenic tempering process.

Abstract: An earth boring bit is shown having a bit body and at least one cutter rotatably secured to the bit body. The cutter has a plurality of teeth formed integrally thereon and arranged in circumferential rows. Each of the teeth includes an outer end, an inner end, a pair of flanks and a crest which transversely connects the ends and flanks. During the manufacturing process, a temporary protective coating is applied at a region of the tooth root which comprises a sharp corner at the intersection of the flanks and ends in order to prevent a carburized case from forming in that region during subsequent carburization of the cutter. The cutter is then carburized, heat treated and mounted on a bit body.

Abstract: A drill steel-chuck assembly which includes a drill steel which has a plurality of faces and opposite ends. The drill steel has one portion adjacent one of the opposite ends thereof and a mediate portion spaced apart from the one portion. The drill steel further has one transition portion between the one portion and the mediate portion so as to join the one portion and the mediate portion. The one portion of the drill steel presents a first orientation of the faces. The mediate portion of the drill steel presents a second orientation of the faces. The one transition portion of the drill steel presents a twisted orientation of the faces comprising a generally constant twist of the faces from the first orientation of the one portion to the second orientation of the mediate portion. There is a chuck for attachment to the drill steel through engagement with the transition portion of the drill steel.

Abstract: A method is disclosed for forming a drill bit structure to which a cutting element is to be affixed. The method includes applying a layer of hardfacing material to a basic bit structure, removing the layer of hardfacing material in a location to which the cutting element is to be affixed, and forming an attachment structure at the location. In one embodiment, the removing is performed by electrode discharge machining. In one embodiment, the basic bit structure is a roller cone, and the cutting element is an insert adapted to be interference fit within a socket in the roller cone.

Abstract: A method for mounting a casing shoe (4) around a cylindrical drilling apparatus (2), which shoe is used by drilling and pulled in the ground on drilling, whereby shoe (4) and drilling apparatus (2) can in the installed position rotate with respect to one another and move a certain distance axially with respect to one another, when shoulder (8) in the shoe is in transverse groove (9) on the periphery of the drilling apparatus and the groove is determining the length of the axial motion. The cylindrical shoe (2) is shrunk in order to make its diameter smaller around a spot in drilling apparatus (2) smaller than the outer diameter (Du), until through shrinking the outer diameter of the shoe has become smaller than the outer diameter (Du) of the drilling apparatus.

Abstract: A method for use in designing rotary drill bits comprises determining locations in which cutters are to be provided, determining likely wear rates for cutters positioned at those locations, and using the likely wear rates to chose between relatively high and relatively low wear rate cutters for each location. The cutters all have substantially the same impact toughness.

Abstract: A rotary cone bit, having a functionally-engineered surface of this invention, comprises a bit body having at least one leg extending therefrom, and a cone that is rotatably disposed on the leg. The cone typically comprises a plurality of cutting elements that project outwardly therefrom. The cutting elements comprises a cermet material selected from the group consisting of refractory metal carbides, nitrides, borides, carbonitrides and mixtures thereof. A functionally-engineered material is disposed over a surface portion of at least one of the cutting elements to form a wear resistant surface thereon. The wear resistant surface has a hardness that is different than that of the underlying cutting element. The wear resistant surface is provided by forming a conformable material mixture by combining one or more powders selected from the group consisting of cermets, carbides, borides, nitrides, carbonitrides, refractory metals, Co, Fe, Ni, and combinations thereof, with an applying agent.

Abstract: A mold is formed for an building earth boring bit by designing the bit geometry in three dimensions using a computer aided design (CAD) system and then feeding the geometry data of the design to a layering device. The layering device then builds the mold a layer at a time. Materials used in building the mold include, sand, graphite, ceramic, clay, other refractory materials, plastic, rubber and wax. Once the mold is formed, powdered steel or tungsten carbide is poured into the mold and is cured by press molding or infiltrating with a binder forming a bit body. Cutting elements are then inserted in the bit body forming the earth boring bit.

Abstract: Composite constructions of this invention comprise a first structural phase formed from a hard material selected from the group consisting of cermet materials, polycrystalline diamond, polycrystalline cubic boron nitride, and mixtures thereof, and a second structural phase formed from a material that is relatively softer than that used to form the first structural phase. The material selected to form the second structural phase can be the same or different from that used to form the first structural phase. The second structural phase is positioned into contact with at least a portion of the first structural phase. The composite construction includes repeated structural units that each comprise an ordered microstructure of first and second structural phases.

Abstract: Using inserts which are welded in place allows the use of hardfacing in the immediate vicinity of the inserts. Areas of high wear, such as cutting structures and gage areas, can use a combination of ultra-hard inserts with hardfacing for protection against wear. The inserts slows wear, while the hardfacing prevents erosion around the inserts.

Abstract: A cutter element for use in a drill bit, comprising a substrate and a plurality of layers thereon. The substrate comprises a grip portion and an extending portion. The layers are applied to the extending portion such that at least one of the layers is harder than at least one of the layers above it. The layers can include one or more layers of polycrystalline diamond and can include a layer in which the composition of the material changes with distance from the substrate.

Abstract: A rotary cone drill bit includes at least one leg carrying a journal provided with bearing surfaces cooperating via bearing elements with bearing races in a rotatable cone cutter. The cone cutter is provided with rows of crushing elements. Each crushing element has a greatest width (D) and a greatest height (H), wherein HID<1.2. The crushing elements are welded to the body of the cone cutter to form a metallurgical bond therewith.

Abstract: A drill bit for use in drilling operations in a wellbore, the drill bit having a bit body including a plurality of bit legs, each supporting a rolling cone cutter; a coupling member formed at an upper portion of said bit body; at least one temperature sensor for monitoring at least one temperature condition of said improved drill bit during drilling operations; and at least one temperature sensor cavity formed in said bit body and adapted for receiving, carrying, and locating said at least one temperature sensor in a particular position relative to said bit body which is empirically determined to optimize temperature sensor discrimination.

Abstract: Although particular detailed embodiments of the apparatus and method have been described herein, it should be understood that the invention is not restricted to the details of the preferred embodiment. Many changes in design, composition, configuration and dimensions are possible without departing from the spirit and scope of the instant invention.

Abstract: An improved polycrystalline diamond composite (“PDC”) cutter with secondary PDC cutting surfaces in addition to a primary PDC cutting surface is formed comprising of at least two wafers of cemented carbide bonded together. The secondary cutting surfaces are formed by compacting and sintering diamond in grooves formed at the surface of the wafers. Wafers of different grades of cemented carbide may be used. Moreover, different grades of diamond may be compacted and sintered in different grooves.

Abstract: A method is disclosed comprising the steps of locating, on a surface of a downhole component, a plurality of thermally stable polycrystalline diamond (TSP) bearing elements, and then applying to the surface a settable facing material which bonds to the surface between the bearing elements and embraces the elements to hold them in place. A method in which bearing elements each comprising a body of TSP at least partly surrounded by a layer of less hard material are secured to the surface by welding or brazing part of the surface of each bearing element which comprises said less hard material to said component is also described.

Abstract: A method of manufacturing a bit body, other drilling-related component, or other article of manufacture, including fabricating a particulate-based matrix and infiltrating the particulate-based matrix with a binder that includes cobalt or iron. The binder may be a cobalt alloy or an iron alloy. The particulate-based matrix may be disposed within a non-graphite mold. The particulate-based matrix and binder are placed within an induction coil and an alternating current is applied to the induction coil in order to directly heat the binder, permitting the binder to infiltrate or otherwise bind the particles of the matrix together. The molten binder may then be directionally cooled by forming a cooling zone around an end portion of the bit body and increasing the size of the cooling zone relative to the bit body.

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: A method of fabricating rotary-type drill bits, drilling-related structures, and other articles of manufacture. The method includes fabricating a machinable matrix, machining the matrix, and dispersing a binder material throughout the matrix. The matrix of the rotary-type drill bit may be fabricated by layered-manufacturing techniques or by disposing a particulate or powdered material into a mold and binding the particles together with a resin or by sintering. The matrix may have the desired dimensions and features, the approximate dimensions and features, or lack desired dimensions or features of a drilling-related structure or other article of manufacture. The matrix is machined to correct any anisotropies or imperfections of the matrix, to refine features of the matrix, or to define the features in the matrix. The machined matrix may be infiltrated with a binder material to define a drill bit body.

Abstract: In a shaft-type cutter body of hard material including a shaft for mounting the cutter in a chuck and a head including cutting areas with cutting edges disposed around the circumference of the head, the shaft and the head are formed integrally by injection die casting of powdered raw material followed by sintering. The unfinished cutter body includes cutting edge sections with recessed areas adjacent the cutting edge front surface area for receiving wood chips and delimiting the cutting edge surface area and a surface area receding radially inwardly from the rear cutting edge surface area of the cutting edge so as to limit the rear cutting edge surface area.

Abstract: An earth-boring bit has a bit body with at least one earth disintegrating cutter mounted on it. The cutter is generally conically shaped and rotatably secured to the body. The cutter has a plurality of teeth formed on it. The teeth have underlying stubs of steel which are integrally formed with and protrude from the cutter. The stubs have flanks which incline toward each other and terminate in a top. A carburized layer is formed on the flanks and the top to a selected depth. The stub has a width across its top from one flank to the other that is less than twice the depth of the carburized layer. A layer of hardfacing is coated on the tops and flanks of the stub, forming an apex for the tooth.

Abstract: An excavating tool has a tungsten carbide insert which is more wear resistant and not subject to breakage because of bring too brittle. The insert has a semispherical tip, a divergent midsection and a base with a conical rear surface. The insert is made with tungsten carbide particles sized between 1 and 8 microns and averaging between 2 and 5 microns, blended with particles of a binder of which the binder comprises 5.5 to 6.5 percent of the blend by weight, and the insert is sintered to a hardness of 89.5 Ra or more.

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 cutting tool (200, 202) has a longitudinally extending shaft portion (208) with a chucking part (204) and a cutting head (206). A cutting edge (220) is formed on the cutting head (206). The cutting edge (220) includes at least one cutting portion. A rake surface (224) is formed adjacent to at least one of the cutting portions (220) with the rake face being at a rake angle in the range from about −10° to about 10°. A clearance face (226) is formed adjacent to the at least one cutting portion opposite the rake face (224). The clearance face (226) is at a clearance angle in the range from about 10° to about 50°. An edge radius between the rake face and the clearance face is at a radius of from about 0.0003 to about 0.0040 inch.