Abstract: In one embodiment, composite constructions of the invention are in the form of a plurality of coated fibers bundled together to produce a fibrous composite construction in the form of a rod. Each fiber has a core formed from a hard phase material, that is surrounded by a shell formed from a binder phase material. In another embodiment of the invention, monolithic sheets of the hard phase material and the binder phase material are stacked and arranged to produce a swirled composite in the form of a rod. In still another embodiment of the invention, sheets formed from coated fibers are arranged to produce a swirled composite. Inserts for use in such drilling applications as roller cone rock bits and percussion hammer bits, and shear cutters for use in such drilling applications as drag bits, that are manufactured using conventional methods from these composite constructions exhibit increased fracture toughness due to the continuous binder phase around the hard phase of the composites.

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: 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 drill bit for drilling casing in a well bore. The drill bit is constructed from a combination of relatively soft and relatively hard materials. The proportions of the materials are selected such that the drill bit provides suitable cutting and boring of the well bore while being able to be drilled through by a subsequent drill bit. Methods of applying hard materials to a soft material body are provided.

Abstract: A drill bit stabilizing system comprising a body member having an axis and at least one recess formed in the body member housing at least one stabilizing member when in a first retracted position. The stabilizing member is positionable along a diagonal angle with the axis to a second extended operating position which extends downward and outward relative to the main body to selectively engage the surface of a pilot bore hole wall during a drilling operation so as to stabilize an under gauge drill bit used in association with the stabilizing system. The body member further comprises at least one fixed stabilizing surface positioned in an axially spaced relationship to the at least one moveable stabilizing member. The body member further comprises a gauge cutter positioned above the moveable stabilizing member and below the fixed stabilizing surface to expand the pilot hole to the final gauge.

Abstract: A lead-free steel for machine structural use with excellent machinability and low strength anisotropy, which does not contain Pb and is equal to or higher than a conventional Pb-containing free cutting steel in properties, is provided. This steel includes, on the weight basis, C: 0.10 to 0.65%; Si: 0.03 to 1.00%; Mn: 0.30 to 2.50%; S: 0.03 to 0.35%; Cr: 0.1 to 2.0%; Al: less than 0.010%; Ca: 0.0005 to 0.020%; Mg: 0.0003 to 0.020%; O: less than 20 ppm; and the balance being Fe and inevitable impurities.

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 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: 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: 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: 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 method of forming milled teeth on a roller cone of a milled tooth roller cone rock bit includes shaping a crest of a chisel shaped milled tooth on the roller cone. The crest is shaped such that the crest has a convex profile from one corner to an opposite corner of the crest. Such a 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. Further, the forming includes radiusing each of the corners at the ends of the crest of the chisel shaped milled tooth.

Abstract: In one embodiment, composite constructions of the invention are in the form of a plurality of coated fibers bundled together to produce a fibrous composite construction in the form of a rod. Each fiber has a core formed from a hard phase material, that is surrounded by a shell formed from a binder phase material. In another embodiment of the invention, monolithic sheets of the hard phase material and the binder phase material are stacked and arranged to produce a swirled composite in the form of a rod. In still another embodiment of the invention, sheets formed from coated fibers are arranged to produce a swirled composite. Inserts for use in such drilling applications as roller cone rock bits and percussion hammer bits, and shear cutters for use in such drilling applications as drag bits, that are manufactured using conventional methods from these composite constructions exhibit increased fracture toughness due to the continuous binder phase around the hard phase of the composites.

Abstract: Drill bit bodies are provided having one portion formed of one composition and a further portion formed of a different composition. The different compositions provide different functional properties to respective portions of the drill bit body. Methods for forming such drill bit bodies are also provided.

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: 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 sharpening method and associated sharpening means (1) for a drilling tool (2), which is set with grinding segments (3) comprised of hard material. The sharpening means (1) is filled with abrasive materials (6) and is chordlike.

Abstract: A drill bit has a bit body and 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 has a substrate having a convex crest and a layer of hardfacing applied to the 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 rotatable point-attack bit retained for rotation in a block bore, and used for impacting, fragmenting and removing material from a mine wall. An improved elongated tool body having at the front end a diamond-coated tungsten carbide wear tip that is rotationally symmetric about its longitudinal axis and contiguous with a second section steel shank at the rear end. The two distinct parts are joined by a high impact resistant braze at ratios that prevent tool breakage.

Abstract: The present invention generally provides an apparatus and method for forming a pilot hole in a formation. In one aspect of the present invention, the apparatus may comprise a starter mill connected to a bearing mill by a body joint. The apparatus may further comprise a lead bearing connected to a starter mill by a lead joint. Preferably, an outer diameter of the bearing mill is about the same as an inner diameter of a wellbore. As the lead bearing travels along the concave, the apparatus will bend between the bearing mill and the lead bearing. The bend urges the starter mill into contact with the wellbore wall. In another aspect of the present invention, a method for forming a pilot hole in a wellbore includes running a tool into the wellbore, the tool comprising a starter mill disposed between a first bearing and a second bearing. While running the tool along a concave of a whipstock, the tool bends between the first and second bearing and urges the starter mill to form the pilot hole.

Abstract: A down hole rock drill bit and method of manufacture of the same comprising a cast metal drill bit body having a plurality of hardened carbide studs partially cast in the drill bit body. The drill bit is cast by means of a foam pattern replicating the drill bit, typically made from polystyrene within which a plurality of carbide studs are partially inserted into the grinding surface of the foam drill bit model. The model is then subsequently supported within a vessel of sand and molten metal is poured over the foam, vaporizing it and taking the exact form of the foam pattern and permanently retaining the carbide studs within the metal drill bit.

Abstract: PCD and PCBN composite constructions have an ordered structure of two or more material phases that are combined together in a packed or interwoven configuration. One of the material phases is formed from materials selected from the group consisting of: polycrystalline diamond, polycrystalline cubic boron nitride; carbides, borides, nitrides, and carbonitrides from groups IVA, VA, and VIA of the Periodic Table; and mixtures thereof. Another material phase is preferably formed from a material having a degree of ductility that is higher than that of the first material phase. Example second material phase materials include those selected from the group consisting of cermets, Co, Ni, Fe, W, Mo, Cu, Al, Nb, Ti, Ta, and mixtures thereof.

Abstract: Method of introducing instruments/measuring equipment/tools into formations (9) in the earth's crust or other solid materials, such as ice, by means of a drilling device (1), material being liberated by, for example, rotation of a drill bit (2), or by melting, for example by means of a heating element, the liberated material thereafter flowing, or being pumped, past/through the drilling device (1) and being deposited in the bore hole (18) above/behind the drilling device (1). A drilling device (1) for practising the method described above, comprising necessary components, for example a drill bit (2), a driving motor (4), and a steering/control component (7), the drilling device (1) being provided with a cable magazine (10) containing a cable (12), and possibly with an output feeder (11).

Abstract: A hardfacing composition for a drill bit is disclosed which includes a carbide phase made from about 80% to less than 100% by weight of a combination of sintered carbide pellets and crushed cast carbide and from more than 0% to about 20% by weight of carburized tungsten carbide. The composition includes a binder alloy. A roller cone drill bit includes a bit body and at least one roller cone rotatably mounted to the bit body. The at least one roller cone includes at least one cutting element. The cutting element has on its exterior surface a hardfacing. The hardfacing on the cutting element was formed with a hardfacing composition that includes a binder alloy and a carbide phase, which includes from about 80% to less than 100% by weight of a combination of sintered carbide pellets and crushed cast carbide, and from more than 0% to about 20% by weight of carburized tungsten carbide.

Abstract: A fracture and wear resistant rock bit is disclosed, which includes a bit body, and at least one roller cone disposed on the bit body adapted such that at least one row of cutting elements disposed on the at least one roller cone defines a gage row. At least one cutting element disposed on the gage row has a fracture toughness of at least 20 ksi (in)0.5 and a wear number of at least 1.5.

Abstract: 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. A mold that may be employed to fabricate the drill bit includes an initially conforming mold region, in which the prefabricated bit crown may be disposed, and a second, substantially rigid mold region including a cavity to define the gage of the drill bit. Preferably, the conforming mold region is formed of a nonwettable, granular material.

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: 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: Disclosed is a polycrystalline diamond or diamond-like element with greatly improved wear resistance without loss of impact strength. These elements are formed with a binder-catalyzing material in a high-temperature, high-pressure (HTHP) process. The PCD element has a body with a plurality of bonded diamond or diamond-like crystals forming a continuous diamond matrix that has a diamond volume density greater than 85%. Interstices among the diamond crystals form a continuous interstitial matrix containing a catalyzing material. The diamond matrix table is formed and integrally bonded with a metallic substrate containing the catalyzing material during the HTHP process. The diamond matrix body has a working surface, where a first portion of the interstitial matrix in the body adjacent to the working surface is substantially free of the catalyzing material, and a second portion of the interstitial matrix in the body adjacent to the working surface contains the catalyzing material.

Abstract: The present invention provides an earth boring drill bit with 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. This translates to higher wear resistance in cutting applications and has advantages in numerous other applications.

Abstract: A fracture and wear resistant rock bit is disclosed, which includes a bit body, and at least one roller cone disposed on the bit body adapted such that at least one row of cutting elements disposed on the at least one roller cone defines a gage row. At least one cutting element disposed on the gage row has a fracture toughness of at least 20 ksi (in)0.5 and a wear number of at least 1.5.

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: 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 of the present invention 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 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 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: In one embodiment, composite constructions of the invention are in the form of a plurality of coated fibers bundled together to produce a fibrous composite construction in the form of a rod. Each fiber has a core formed from a hard phase material, that is surrounded by a shell formed from a binder phase material. In another embodiment of the invention, monolithic sheets of the hard phase material and the binder phase material are stacked and arranged to produce a swirled composite in the form of a rod. In still another embodiment of the invention, sheets formed from coated fibers are arranged to produce a swirled composite. Inserts for use in such drilling applications as roller cone rock bits and percussion hammer bits, and shear cutters for use in such drilling applications as drag bits, that are manufactured using conventional methods from these composite constructions exhibit increased fracture toughness due to the continuous binder phase around the hard phase of the composites.

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: A tool for effecting drilling and/or chiseling and including a tubular shaft (2,22) having an axially extending through-channel (8,28) and provided, at one of its axial ends, with a drilling or chiseling head (5), and a connection member (3,23) connected with another of axial ends of the shaft and provided at its end remote from the shaft (2,22) with a shank (4,24), the through-channel (8,28) being connected with the tool circumference by a cross-bore (7,27), and the largest cross-sectional surface (A1,A4) of the connection member (3,23) corresponding at least to 2.5 times of the largest cross-sectional surface of the shank (4,24).

Abstract: A composition for drill bit bodies and a method for making drill bits from the composition are disclosed. The composition includes powdered tungsten carbide, and binder metal consisting of a composition by weight of manganese in a range of about zero to 25 percent, nickel in a range of about zero to 15 percent, zinc in a range of about 3 to 20 percent, tin in a range of more than 1 percent to about 10 percent, and copper making up the remainder by weight of the composition. In one embodiment, the composition includes about 6 to 7 percent tin therein. The composition is heated to at least the infiltration temperature in a mold for form a drill bit body.

Abstract: Composite constructions of this invention comprise an ordered microstructure made up of multiple structural units that can be the same or different, and that comprise at least a first structural phase and a second structural phase. The first structural phase comprises a hard material that is selected from the group consisting of cermet materials, PCD, PCBN and mixtures thereof. The second structural phase is in contact with the first phase and comprises a material that is different than that selected to form the first structural phase. Additionally, the second structural phase is in contact with at least a portion of the first structural phase. Composite constructions of this invention can also have a multi-layer structures comprising two or more layers, wherein at least one of the layers comprises a composite construction having an ordered microstructure made up of the multiple structural units described above.

Abstract: An earth-boring bit has hardfacing that has multiple grades and an overlapped portion. One of the layers is of a different grade than the other so as to provide more wear resistance. The other provides more toughness than the wear resistant layer. The more wear resistant layer has a greater volumetric density of carbide particles. The greater density is primarily achieved by using a majority of the particles of smaller dimension than in the less wear resistant hardfacing. The overlapped portion may be on an outer or gage end of the outer row of teeth.

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 percussive drilling component includes a cylindrical male screw thread formed of a steel material. The thread includes thread crests and thread roots interconnected by thread flanks. To protect the thread against corrosion, the thread is coated with a material having a higher electrode potential than the steel material. The coating is situated at least in regions located radially inwardly of the thread flanks. The male screw thread can be attached to a female screw thread of another percussive drilling component, the female screw thread also being coated with the material.

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: 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: A method of manufacturing a rolling cone with hard-facing coating for use in drilling boreholes is disclosed. The method includes a step of depositing a layer of hardfacing material by an arc process, e.g., a gas-shielding tungsten arc welding process, a plasma-transferred arc welding process, or a metal inert gas arc welding process, over areas susceptible to erosion on the rolling cone surface. A rolling cone rock bit for drilling boreholes with a layer of hardfacing material deposited by an arc process either on the lands or in grooves or both of the cone surface is provided. Furthermore, a cone for attachment to the bit body of a rock bit with a layer of hardfacing material deposited on selected lands or in selected grooves or both of the cone surface also is provided.

Abstract: A rotary drill bit is manufactured by a powder metallurgy process by placing a metal mandrel in a mold, packing the mold with particulate matrix-forming material, infiltrating the material with a molten binding alloy, and cooling the assembly to form a solid infiltrated matrix bonded to the mandrel. The mandrel comprises an outer part surrounded by the matrix-forming material and an inner part, secured to the outer part but out of contact with the matrix-forming material. The outer part of the mandrel is formed from a material having thermal characteristics close to those of the matrix, so as to reduce the tendency for the matrix to crack under thermal stress, while the inner part of the mandrel is formed from a precipitation-hardening material, the strength and hardness of which increases in the infiltration process and the subsequent heating/cooling cycle for brazing the cutters on to the drill bit.

Abstract: A rotary earth-boring drag bit assembly has a bit body formed of a carbide matrix material. The body has a longitudinal axis and a face on a lower end containing cutters for engaging and cutting a bottom of the borehole. The cutters are carried on fixed blades extending about and radially outwardly of the face. A steel threaded pin member is bonded to an upper end of the body. A steel shank having a threaded receptacle on a lower end secures to the threaded pin member. The steel shank has a threaded pin on an upper end that secures to a drill string. A lower set of gage pads is disposed about a periphery of the body and extends longitudinally away from the face for engaging a sidewall of the borehole. Each of the gage pads is contiguous with and extends from one of the blades. The gage pads are elongated in an axial direction and protrude from the periphery. Slots are located between the gage pads for the flow of drilling fluid and cuttings.

Abstract: A nozzle sleeve for the retention of replaceable fluid nozzles for rock bits is disclosed. The sleeve is secured within the body of the rock bit. A first upstream end of the sleeve communicates with a fluid plenum formed by the bit body. A second downstream end of this sleeve is adapted to receive the fluid nozzles. An elliptical fluid entrance is formed at the first upstream end of the nozzle sleeve. The elliptical fluid inlet formed by the sleeve serves to increase the flow of fluid to the nozzles, reduce turbulence of the fluid and substantially reduce the erosive effects associated with high fluid velocities and turbulent flow.