Abstract: A drill bit for use in combination with a through-the-steel drill stem, the drill bit including an elongated body portion having a bore through which cuttings may be removed, a web extending transversely across the bore for receiving a drill tip, and drill ports leading from the drill tip to the bore and from the periphery of the body portion to the bore, the drill ports comprising opposed axially extending openings contoured as a hemisphere to define opposed axially extending faces of the web and opening to the bore from the drill tip and extending axially along the body portion and opening from the periphery thereof to the bore below the web. The drill bit may be provided with a sleeve to delimit the drill ports.

Abstract: An improved earth boring bit of the type having diamond cutting elements and a fluid passageway to direct drilling fluid toward a borehole bottom during drilling, a metal nozzle with a cylindrical, threaded exterior and a noncircular throat having a minimum cross sectional dimension to receive a mating wrench and a length to resist damage from the torque required to make-up and break-out the nozzle for threads in the body of the bit.

Abstract: A bit is shown for use in drilling earthen formations which includes a body having a bit face on one end and a shank on the opposite end which is connected in the drill string. The bit body has a tubular bore which communicates with an interior bore of the drill string for circulation of fluids. The bit face increases in external diameter between a nose and a gage region of the bit. A fluid opening communicates the bit face with the tubular bore for circulating fluid to the bit face. A plurality of fluid courses are disposed on the bit body, the fluid courses becoming ever wider and ever deeper along their entire disposition from their lowermost incorporation through the gage region thereof.

Abstract: A method of manufacturing by a power metallurgy process a rotary drill bit including a bit body having an external surface on which are mounted a plurality of preform cutting elements, and an inner passage for supplying drilling fluid to at least one nozzle located in a socket at the external surface of the bit. The method includes the steps of forming a hollow mould for moulding the bit body, packing the mould with powdered material, such as tungsten carbide powder, and infiltrating the material with a metal alloy in a furnace to form a matrix. Before packing the mould with the powdered material, there is positioned in the interior surface of the mould at least one former which projects into the interior of the mould space at the desired location for a nozzle socket, the former having an external screw thread whereby the matrix material packed around the former becomes shaped with a corresponding internal screw thread.

Abstract: A stabilized drill bit has a cylindrical main body, a formation cutting face at the lower end of the body, and means by which the upper end of the bit can be connected into a drill string. A drilling fluid flow passageway extends axially through the main body and provides flow of drilling fluid to the drilling face. A plurality of hydraulic actuated stabilizing members are arranged circumferentially about the throat and within the main body. Stabilizing members have a borehole wall engaging face thereon which can be retracted flush with the outer surface of the main body, and extended away from the main body face and into contact with the borehole wall, thereby stabilizing the drill bit as the bit is rotated while making hole.

Abstract: A drill bit having a nozzle for drilling fluid to pass out of the drill bit and into the bore hole is disclosed. In one embodiment two diagonal passages through the nozzle impart angular momentum to the drilling fluid. In another embodiment, four diagonal passages through the nozzle impart angular momentum. In still another embodiment, a central bore hole through the nozzle has helical grooves along its internal orifice wall to impart angular momentum. The angular momentum causes the drilling fluid exiting from the interior of the drill bit to flow downward into the bore hole in a divergent vortex that sweeps the cuttings away from the cutting surfaces of the drill bit.

Abstract: A drill bit for use in unconsolidated formations includes a generally triangular cross-section that tapers toward the lower tip end of the tool. The vertices of the triangular cross-section carry blade members that cut and define the size of the bore hole. Nozzles positioned between the blades and upon the tapered portion of the tool break up unconsolidated formation material that has been cut.

Abstract: An automatic broken-drill-pipe-intercoupling tool having, a body portion with, at one end, a female threaded adapted to cooperate with the threaded male end of the retrievable portion of a broken drill pipe and at the other end a tapered, multi-interwined-spiral bit portion, integral with the body portion, the body portion having flats thereon to permit tightening of the tool on the retrievable portion of the broken drill pipe.

Abstract: A full bore drag-type well drilling bit comprises a bit body having an operating end face defining a plurality of upsets. Each of the upsets has a leading edge surface and at least one recess extending through the leading edge surface into the upset. The end face of the bit body further comprises a plurality of flow channels, each such leading edge surface having one such flow channel extending therealong and inset therefrom. At least some of the upsets have a plurality of such recesses spaced therealong. The bit body further has a plurality of circulation ports opening through its end face and a plurality of nozzles, each nozzle being mounted in a respective one of the ports. The number of nozzles is less than the number of flow channels. At least some of the nozzles communicate with more than one such flow channel, and the transverse cross-sectional flow area of each of the nozzles is substantially less than those of individual ones of the channels communicating therewith.

Abstract: A vibratory earth penetrator employing a high pressure air distributor and an oscillating mechanism has the ability to dig down to underground utilities and contact those utilities without damaging them. The invention includes a hollow elongated tube having a plurality of air lances at the bottom end thereof. The air is preferably distributed to the air lances by an air distributor in a criss-cross sequence. An oscillating eccentric weight is synchronized with the air distributor to enhance the digging effect of the device. The penetrator is supported by a boom which includes an automatic tension device for providing sufficient upward force to keep the penetrator in the vertical attitude while allowing the weight of the penetrator to provide enough force to permit the device to dig into the ground. Since the digging action is accompanied by very little downward force, it is possible to contact underground utilities without hurting them.

Abstract: This invention relates to multi-cone rock bits with three or more nozzles of varying length to affect different flow velocities from each of the nozzles. The nozzles at different lengths create a crossflow of fluid on a borehole bottom to lift detritus therefrom during rock bit drilling operations.

Abstract: A threaded nozzle is adapted to be screwed into and screwed out of a threaded opening in a drill bit. The nozzle includes a front face having first and second contact surfaces which are adapted to be engaged by a manually actuable tool for screwing-in and screwing-out the nozzle. The first contact surface is inclined toward the direction of rotation in which the member is screwed-in, so that in response to the application of a force to the first contact surface for screwing-in the nozzle, a reaction force is applied against the tool for pushing the tool off the first contact surface when the nozzle has been screwed-in a predetermined extent.

Abstract: An improved drill bit and a method for making the same. A body having an upper end is adapted for connection to a source of rotary motion. A curved surface formed on the lower end of the body includes a plurality of cutting elements embedded therein. A port provides drilling fluid between the curved surface and the bore during drilling. The cutting elements and fluid courses formed on the curved surface define a gap between the surface and the bore during drilling. The gap is formed to provide no more than a substantially linear reduction in drilling fluid pressure with increasing bit radius. In making the bit, a bottomhole pattern and a substantially constant flow area are selected. Dimensions of the lower drill bit surface are calculated to provide the selected flow area over the surface when the bit is in position above the bottomhole pattern.

Abstract: A rotary drill bit includes a cutting face having a peripheral edge and a central recess. A plurality of fluid discharge nozzles are mounted in bores in the cutting face. A plurality of cutter elements are mounted in the peripheral edge and in the recess to fracture an earthen core formed as the drill cuts through a formation. A plurality of lateral discharge passages extend radially through the bit body from said recess and extend longitudinally to the peripheral edge to form circumferential interruptions in the peripheral edge. Each passage includes leading and trailing edges at the cutting face. A convex protrusion is disposed centrally at a longitudinally inner end of the recess and includes a convex deflecting surface arranged to contact and fracture the earthen core and deflect the cuttings to the lateral discharge passages. The outer periphery of the cutting face is radially recessed to accommodate the flow of drilling fluid.

Abstract: A rotary drill bit comprising a tubular strainer element co-axially arranged within the body of the bit and being provided with narrow axial slots arranged to prevent solid debris from passing to the nozzles of the bit. The self-cleaning ability of the strainer element is enhanced by increasing the bore of the strainer element in the region below the slots.

Abstract: A bit for a core drill of the type for drilling a chamfered hole in an article has a dynamic cooling fluid flow directing element for cooling the bit and article surfaces during drilling and chamfering of the article.

Abstract: A drill bit for use in combination with a through-the-steel drill stem, the drill bit including an elongated body portion having a bore through which cuttings may be removed through the drill stem, a web for receiving a drill tip, and a sleeve attached about the body portion thereof, the web thereof having axially extending faces coutoured from the periphery of the body portion toward the axis thereof, and the sleeve extending from the body portion and in spaced apart axial relation to the contoured faces of the web in a manner to define drill cut receiving ports opening upwardly to the drill tip and downwardly to the bore of the body portion. The drill bit may be provided with a male keeper or retainer to mate with a complementary female receptor of the drill stem for interconnection of the drill bit to the drill stem.

Abstract: A drilling fluid nozzle for an earth boring bit is formed entirely of tungsten carbide, having hard-ground threads on its exterior for securing in the bit passage. The nozzle has an upwardly facing shoulder located below the threads which sealingly engages a downwardly facing shoulder formed in the bit passage. An O-ring seal is located above the threads.

Abstract: A rotary bit for use in subsurface formations comprises a bit body having a central bore (4), the body having a leading face (1) and a trailing gauge region (2), walls (7) on the bit dividing the face into fluid channels, cutting elements C being present on at least some of the walls, and passageways (5) connecting the bore (4) to openings (6) in the fluid channels. At least two wall portions (7) are arranged relative to each openings (6) so that the fluid emerging from the opening is directed to travel first inwardly towards the central axis of the bit before travelling outwardly to the gauge region (2).

Abstract: A mineral mining pick 1, a holder for such a pick, and the combination of such a pick with a holder 2. The pick has a head 3 with a cutting tip 5 and a shank 4 which is received in a shank socket 6 of the holder 2. Retaining means 7 is provided to releasably secure the pick in the holder. Extending through the pick is a water passage 11 which communicates with outlet ports 12 in the pick head for water flow to suppress dust and cool the tip 5. The passage 11 communicates with a socket 15 which mates with a tubular spigot 13 which is an extension to a fluid supply passage 2a in the holder 2. The spigot 13 is mounted by a resilient sleeve 22 in a tubular housing 19 by which it is removably retained in the holder 2. The sleeve 22 permits displacement of the spigot 13 to accommodate misalignment between the spigot and the socket 15 during coupling thereof as the shank is inserted into its socket 6.

Abstract: Replaceable nozzles may be provided in a tungsten carbide drill bit manufactured by powder metallurgical infiltration techniques wherein at least one nozzle is threaded into a corresponding molded threaded bore in the bit. Despite the practical nonmachinability and brittleness of the tungsten carbide material, secure threaded insertion can be achieved if a squared thread design is used, and if the mold plug for forming the threaded bore is oversized to take into account the average variation in shrinkage in a bit formed by powder metallurgical infiltration techniques.

Abstract: An improved rotating diamond bit for earth boring is devised by incorporating generally triangular, prismatically shaped synthetic polycrystalline diamond elements in the teeth of the boring bit. The polycrystalline diamond elements are set on lands defined on the bit face such that two opposing triangular faces of the prismatic diamond element form a dihedral angle in the direction of travel of the element defined by the bit rotation. The polycrystalline diamond element is thus inclined with respect to the direction of linear travel of the element when the bit rotates. In other words, the normal to the parallel opposing triangular faces of the diamond element is acutely inclined with respect to the direction of travel of the element. A shoulder-to-gage transition pattern of the junk slot, waterway and collector is arranged to uniformly distribute the flow of fluid across the shoulder to guage transition.

Abstract: A bit holder equipped with a spraying device, comprising a receiving bore (2) in which the bit shaft (3) is supported, for limited axial shifting movement and optionally for being rotated, shifting movement of the bit shaft (3) in direction of the cutting pressure being limited by abutment (5) and the bit shaft being loaded by a return force in opposite direction to the cutting pressure and a valve (10, 11) for the supply of water to the bit or to the working or drift face during cutting operation being arranged within the bit holder (1) and being opened under the action of the cutting pressure by the axial shifting movement of the bit shaft (3). The valve housing (9) is inserted into the receiving bore (2). The rear end of the bit shaft (3) acts directly on the shaft (12) of the valve cone (10).

Abstract: A nozzle assembly for an earth boring drill bit of the type adapted to receive drilling fluid under pressure and having a nozzle bore in the bottom thereof positioned closely adjacent the well bore bottom when the bit is in engagement therewith with the bore having inner and outer portions. The nozzle assembly comprises a generally cylindrical nozzle member of abrasion and erosion resistant material, selected from a plurality of such members, each being of the same outer diameter but having passaging therein of different cross-sectional area. The nozzle member is adapted to be fitted in the inner portion of the nozzle bore in sealing relationship therewith for forming a first seal for the nozzle assembly. The nozzle assembly further comprises a locknut, separate from the nozzle member, for detachably securing the nozzle member in the nozzle bore, formed at least in part of an abrasion and erosion resistant material.

Abstract: The present invention includes an insert securably mountable within the chamber of a core drill, such as a chamfering diamond core drill used for drilling and chamfering glass articles. The insert preferably includes a first diverting facility for diverting a first portion of a lubricating/cooling fluid from within the core drill to the inner drilling surfaces of the core drill, and a second diverting facility for diverting a second portion of the lubricating/cooling fluid to the outer drilling surface and chamfering surface of the core drill, to prevent thermal damage to the article being drilled and chamfered, during both the drilling and chamfering steps. The present invention further includes a method of lubricating/cooling an article during drilling and chamfering operations with lubricating/cooling fluid from within the core drill, to prevent thermal damage to the article being drilled.

Abstract: A drill bit with multiple fluid jet cutting nozzles designed so that the drill bit workface including the cutters is a separate piece from the drill bit body that houses the fluid jet nozzle orifice mounts. The cutter assembly protects the nozzle housing from rapid wear and it can be easily removed from the nozzle housing without disturbing or removing any of the nozzle orifice mounts.

Abstract: A rotary drill bit includes a cutting face having a peripheral edge and a central recess. A plurality of fluid discharge nozzles are mounted in the cutting face. A plurality of cutter elements are mounted in the peripheral edge and in the recess to fracture an earthen core formed as the drill cuts through a formation. A plurality of lateral discharge passages extend radially through the bit body from said recess and extend longitudinally to the peripheral edge to form circumferential interruptions in the peripheral edge. A convex protrusion is disposed centrally at a longitudinally inner end of the recess and includes a convex deflecting surface arranged to contact and fracture the earthen core and deflect the cuttings to the lateral discharge passages.

Abstract: The invention relates to the geometry of drill bits for jet assisted rotary drilling. According to the invention there is used a drill bit comprising platelets of small radial dimension disposed about a central burster in a discontinuous peripheral crown axially extending said drill bit, channels for supplying pressurized fluid opening from the crown close to the platelets. Said platelets are preferably separated from one another by rectilinear discharge ramps. A drill bit in accordance with this invention can be manufactured e.g. by turning or milling. It can be applied for drilling rock formations in mines, and other hard materials.

Abstract: An abrasive-fluid jet apparatus and process for drilling holes in rock having a rotary drill bit with multiple abrasive-fluid jet nozzles in the face of the bit and a stationary drill head housing torque generation apparatus and a rotary mounting holding the rotary drill bit beneath and in rotatable relation to the drill head. Abrasive supply facilities and fluid supply facilities are located at ground level for separate supply of the abrasive and the fluid to the abrasive-fluid jet nozzles. It is preferred that the abrasive be supplied to the nozzles in the form of slurry or foam. The apparatus and process of this invention permits deep hole drilling at lower fluid pressures than and without surface structures required by current deep drilling apparatus and techniques.

Abstract: A nozzle includes a tungsten carbide body and threaded steel sleeve. The nozzle body includes a fluid jet opening arranged to be reoriented in response to rotation of the nozzle body. The nozzle body includes a first set of apertures for receiving a turning tool. The sleeve comprises a split sleeve retained longitudinally upon the nozzle body and is rotatable relative thereto. The sleeve threads are protectively disposed behind a flange of the nozzle body. The sleeve includes a second set of apertures which are alignable with the first set of apertures adjacent an inner end of the latter. The turning tool is engageable with (i) both sets of apertures for rotating the nozzle body and sleeve to install the nozzle, or (ii) with only the first set of apertures to rotate the nozzle body relative to the sleeve against the resistance of an O-ring to reorient the jet opening.

Abstract: Mineral mining apparatus comprising a pick head 1 mounted on a pick holder 4 for displacement of a cutting part 5 in the direction of arrow A has a nozzle 9 in the head 1 through which nozzle water is sprayed for dust suppression, cooling or flushing purposes. The characteristics of the nozzle 9 provide the spray 22 with a flat configuration where the width y of the spray is greater than its depth x. Preferably the width y lies in the cutting plane 20 of the cutting part and the spray follows the cutting part to alleviate incendive sparking.In a modification the nozzle 9 can be mounted on the holder 4.

Abstract: Earth-boring drill bits with one or more substantially rectangular nozzles through which drilling fluid is discharged to clean and cool the bit cutters and flush the cuttings produced by the bit from the drilling region to the top of the bore hole. The rectangular nozzle is more effective in cleaning and cooling the cutters and in removing the cuttings, when compared with the results achieved with the nozzle having a round or circular bore. The rectangular nozzle has a larger cross-sectional area than a circular nozzle while providing substantially the same fluid pressure drop across the nozzle, larger particles in the drilling fluid being capable of passing through the rectangular nozzle which would plug the passage through the circular nozzle. More specifically, rectangular nozzles are highly effective when incorporated in polycrystalline diamond compact bits, in which various cutter arrangements can be used.

Abstract: The flow of drilling fluid across the face of a rotating bit can be improved by disposition of jet nozzles in the middle of pads defined on the rotating bit rather than in or directly communicating with water courses in the bit. Drilling fluid is therefore ejected by the nozzle and flows in a plurality of directions across the face of the pad with a maximal velocity. Drilling fluid arriving in the proximity of the nozzle and provided from other sources in the bit is thus entrained within the drilling fluid which is ejected from the nozzle. This serves then to suction drilling fluid from these other sources. In particular, in a rotating bit having a pilot bit and main reamer bit, drilling fluid supplied to the pilot bit is directed toward a pilot bit junk slot in the immediate proximity of a nozzle disposed in the middle of a reamer lobe. Drilling fluid flowing down the pilot bit junk slot is entrained within drilling fluid ejected by the reamer nozzle.

Abstract: A drill bit for connection on a drill string has a hollow tubular body with an end cutting face and an exterior peripheral stabilizer surface with cylindrical sintered carbide inserts positioned therein. Nozzle passages extend from the interior of the bit body through the cutting face for receiving a removable and interchangeable nozzle member therein. The nozzle has a fluted or non-circular cross-section with grooved portions or out of round portions providing sufficient clearance for drilling fluid to continue to flow through the nozzle even when the main passage thereof is blocked with mud particles or the like. The cutting face has a plurality of recesses therein which receive, by an interference fit, a plurality of cutting elements of the type known as Stratapax, consisting of a cylindrical stud having an angular supporting surface with a cutting disc bonded thereon consisting of sintered carbide having a cutting surface of polycrystalline diamond.

Abstract: A drill bit for drilling a rock foundation is provided having a bit face matrix for supporting a plurality of cutters, the matrix having one or more fluid passages for discharging a fluid to flow over the bit face. To enhance the cleaning and cooling of the plurality of cutters, the bit face matrix includes a nozzle for restricting the surface fluid flow area between the foundation and the bit face to create a high velocity radial fluid flow across the entire surface area of the bit face matrix. This fluid flow prevents debris from accumulating on the plurality of cutters thus providing cooling thereof. In addition, improved fluid distribution is provided by a spiraling dams structure extending from the nozzle radially outward over substantially the entire bit face matrix. This structure enhances the flushing of the debris from the bit face by accelerating the debris and drilling fluid to the outer diameter of the bit.

Abstract: In a drill bit comprising a body having a channel therethrough for carrying drilling fluid for injection into a bore hole through a nozzle at one end thereof and a cutting head mounted in the body and contacting the bottom of the bore hole. The improvement comprises at least one passage extending from the channel to a side portion of the exterior surface of the body wherein drilling fluid in the channel will flow through the at least one passage to the exterior of the body and form a fluid layer between the side portion of the body and the opposing side of the bore hole.

Abstract: A cutting tool and a method of manufacturing such a tool which may be a pick, bit or for a machine tool, in which a hard cutting insert 4 is mounted in a recess 7. Formed between the insert 4 and recess 7 are passages 11 which communicate with a fluid supply passage 13 and through which fluid for dust suppression, lubrication, cooling or removal of detritus is passed to emerge at ports 11a immediately adjacent to the cutting insert in the cutting region of the tool.The insert 4 is preferably formed as a pressing or moulding to include channels which co-operate with opposed walls of the recess 7 to form the passages 11.Preferably the insert 4 is secured in the recess 7 by press fitting and/or by heat shrinking the head 1 of the tool onto the recess to apply compressive retaining forces thereto.In a modification the insert 4 is provided with a sleeve and such assembly is received in the recess 7.

Abstract: A rotary drill bit, particularly for deep-well drilling, comprising a body (1) having a gauge region, a cutting surface which is defined by projecting cutting members (4) supported at the outer periphery of the body on supporting members and nozzle passages (6 ) through which flushing liquid can flow, and in which at least some of the nozzle passages (6) comprise an outlet region which is directed towards the cutting members and which gives the jets of flushing liquid (10') emerging therefrom an alignment with at least one component facing in the direction of the drillings flowing off along the outer face of the body.

Abstract: A blade-type rotary drill bit having radially divergent cutting blades arranged in two arrays and equipped with cutting blanks having upset cutting surfaces formed of an abrasive material such as diamond or the like. The blades in one array cut to the center of the bit to provide a conically shaped core volume and the blades of the second array terminate short of the axis of the bit to define a somewhat larger core volume. The bit is equipped with discharge ports and baffles whereby drilling fluid issuing from the discharge ports moves downwardly and then inwardly to the center of the bit. The cutting blanks located on the second array of blades cut in a common set of tracks which are at least partially different from and compliment the tracks cut by the cutting blanks on the blade of the first array.

Abstract: A cutting device for a mining or tunnelling machine takes the form of a roller with cutter bits which rotates at the end of a movable arm as is known. Grooves in the roller receive plate-like components which support water spray nozzles radially within the extremities of the cutter bits. The support components are stationary but are adjustable about the axis of rotation of the roller to bring the nozzles into the appropriate location during operation.

Abstract: A spraying nozzle for a cutting roller for underground mining, which is located in the vicinity of the cutting bit provided on the blade or closure ring of the roller, has a nozzle shield enclosing the nozzle and coaxially mounted therewith on the respective blade or closure ring of the roller. The nozzle shield is formed with a recess to receive the head of the nozzle and has an upper surface sloping in a direction opposite to the direction of rotation of the cutting roller to reduce wear of the nozzle shield subject to flowing abrasive mineral mined.

Abstract: Drill bit for drilling bore holes in earth formations, the bit's cutting face provided with cutter preforms composed of polycrystalline diamonds on a tungsten carbide substrate mounted in sets from the center of the bit's face to its periphery. The first set consists of one cutter preform at approximately the center of the cutting face. Each succeeding set has at least two preforms, all of which in a set are disposed at an equal radius from the bit's axis of rotation and are displaced from adjacent preforms in the same set by equal arcs around the axis, the cutting path of a set overlapping with that of the next set. The next to last set of preforms is mounted from a surface coinciding with a truncated cone having a relative angle to the bit's axis of rotation of about 33.degree.; the outermost preform set is disposed in or above the junk slots, with each preform mounted extending 90.degree.

Abstract: In a mine tool of the type having a drive body holding a bit, the drive body includes a pair of forwardly projecting flanges forming air passages in proximity to the cutting edges for the conveyance of detritus.

Abstract: A drilling head of the claw-type which eliminates the need for a pilot bit. The configuration to be described hereandafter causes the drill head to run more smoothly and straighter than those claw-type drills having a pilot. The structure includes a threaded stem portion for threadedly affixing the drilling head to a drive source, a platform extending from the stem portion upon which plural drill bits are affixed on a top face thereof in which the platform is formed from three sectors of pyramid shape, and the recess on the top face of the sectors is provided with further bits for cutting outside of the drill head itself.

Abstract: A drill bit for connection on a drill string has a hollow tubular body with an end cutting face provided with a tungsten carbide coated surface and an exterior peripheral stabilizer surface with cylindrical sintered carbide inserts positioned therein. Nozzle passages extend from the interior of the bit body through the cutting face for receiving a removable and interchangeable nozzle member therein. The cutting face has a plurality of recesses therein which receive, by an interference fit, a plurality of cutting elements of the type known as STRATAPAX, consisting of a cylindrical stud having an angular supporting surface with a cutting disc bonded thereon consisting of sintered carbide having a cutting surface of polycrystalline diamond. The recesses in the cutting face have milled offset recesses adjacent to the edges thereof which are sized and positioned to permit the cutting discs to be partially recessed and to restrain the cutting elements from rotation during use.

Abstract: A composite nozzle for a drill bit and a bore enlarging bit, the body of the nozzle, which is adapted to discharge water toward rotary cutters, being fabricated from a ceramic. The nozzle has a bottom surface which is provided with a high-impact metal plate, and a circumferential wall portion also provided with a reinforcing plate.

Abstract: A method and a cutter for producing a large cavity filled with a uniform bed of rubblized oil shale or other material, for in situ processing. A raise drill head (72) has a hollow body (76) with a generally circular base and sloping upper surface. A hollow shaft (74) extends from the hollow body (76). Cutter teeth (78) are mounted on the upper surface of the body (76) and relatively small holes (77) are formed in the body (76) between the cutter teeth (78). Relatively large peripheral flutes (80) around the body (76) allow material to drop below the drill head (72). A pilot hole is drilled into the oil shale deposit. The pilot hole is reamed into a large diameter hole by means of a large diameter raise drill head or cutter to produce a cavity filled with rubble.

Abstract: A drill bit and a method for deep-hole drilling in which the drill bit has mechanical cutting means located on its lower cutting face for cutting a solid surface upon rotation of the bit and a plurality of cavitating liquid jet nozzles spaced around the face of the bit to assist in the drilling action, the nozzles being located so as to discharge a plurality of downwardly directed and concentric liquid jets that cavitate to fracture the surface to be drilled in a series of non-overlapping slots as the bit is rotated.

Abstract: A drill bit for connection on a drill string has a hollow tubular body with an end cutting face and an exterior peripheral stabilizer surface with cylindrical sintered carbide inserts positioned therein and a novel arrangement for securing replaceable nozzles. Nozzle passages extend from the interior of the bit body through the cutting face for receiving a removable and interchangeable nozzle member therein. A portion of the length of each passage is threaded and the remainder of the passage is enlarged and of a smooth bore. The nozzle member is formed of wear-resistant hard metal, e.g. carbide, and has a metal sleeve brazed thereon with male threads operable to be fitted in the threads in said nozzle passage. The nozzle member is threadedly secured in place during installation and optionally further secured against unscrewing and additionally protected against wear or erosion by a metal or hard metal, e.g. carbide, retaining ring having an interference fit in the smooth portion of the nozzle passage.

Abstract: Described is a rotary drill bit comprising a hollow body having a closed lower end and means on the upper end for securing the body to the lower end of a drill string. The body is provided with a plurality of flow passages and a deflecting means is provided to deflect upwardly and away from the flow passages cuttings and the like to avoid plugging the passages during drilling while permitting unimpeded flow from the passages of all the fluid passing through the hollow body.