Abstract: An earth boring bit has a bearing seal that floats to accommodate angular and axial movement of the cutter with respect to the shaft. The seal is located in an annular groove formed in the shaft. A supporting ring is located in the groove. The supporting ring has an inner diameter larger than the inner diameter of the groove to provide a clearance for allowing the supporting ring to float. An elastomeric ring is located on the outer circumference of the supporting ring. The supporting ring presses the elastomeric ring into sealing contact with the cutter. The elastomeric ring is also pressed on its sides to provide sealing.

Abstract: An earth boring bit of the air cooled bearing type has features to improve cleaning of the borehole. The bit has three bit legs, each with a depending bearing pin that receives a rotatable cutter. Bearings are located between the bearing pin and the cutter. Passages communicate drilling fluid from the drill string to the bearings. A slot between the bit leg and the backface of the cutter enables air to be discharged from the bearing pin into the borehole. The portion of the slot on the lower side of the bearing pin is greater in cross-sectional flow area than the portion on the upper side. The portion of the slot on the lower side exposes the outer ends of the roller bearings to the borehole.

Abstract: A rolling cutter drill bit with at least one downwardly extending leg which supports a cantilevered bearing shaft thereon is disclosed. A cutter cone is rotatably mounted on the bearing shaft by radial bearing means and by axial bearing means. A radially disposed thrust washer is positioned between the journal and the cone, the washer further defining a lubricant transferring means in each radially disposed side of the thrust washer to assure adequate lubrication of the roller cone on the journal bearing.

Abstract: A roller reamer assembly for mounting in a longitudinally extending undercut groove in a reamer body and having longitudinally slidable bearing blocks with cooperating locking members for securing the bearing blocks in the groove upon longitudinal movement of the bearing blocks to prevent undesired longitudinal and radial movement of the bearing blocks and an automatic lubricating system for the bearing blocks.

Abstract: A bearing construction for a rotary earth boring drill bit is constructed of a bearing journal and a cutter rotatively mounted on the bearing journal, the bearing journal having a generally cone-shaped bearing wall formed by a plurality of steps comprised of a pair of adjacent walls joined at an apex having an acute included angle, and the cutter having a bearing wall formed with a plurality of steps mating in bearing contact with the steps of the bearing journal.

Abstract: A two-stage vent cap type pressure relief valve for a rock bit is disclosed that relieves low pressure gases in a first stage and higher pressure gases in a second stage.

Abstract: An earth boring drill bit has a lubricant pressure compensator that includes a plunger that moves slidingly in the reservoir to reduce pressure differential, and also allows lubricant to bleed past to relieve excess lubricant pressure. The plunger is carried slidingly in the reservoir. The plunger has a convex end in contact with the lubricant and a concave end in contact with the borehole fluid. The plunger has a rod that contacts a stop in the reservoir when the lubricant pressure is greater than the borehole pressure. Once stopped, the configuration of the plunger allows lubricant to bleed past the plunger to relieve excess lubricant pressure.

Abstract: An earth boring rock bit having a sealed bearing and pressure lubrication system for drilling the earth with air or gas as the circulating medium. An annular groove is formed in the vicinity of the seal and connected to the interior of the bit for cooling the ring and cleaning debris from the area of the ring. The air pressure inside the bit is utilized to bias a movable element in the system to urge lubricant to the bearing.

Abstract: A drill bit with cutting teeth for drilling in rock comprising:a core member having raceways for rolling elements for rotation of the drill bit,a supporting layer exteriorly shaped to define cutting teeth and formed of highly compacted sintered powder material of substantially 90% density, isostatically bonded to said core member,a wear resistant layer applied by thermal spraying and covering only the portions of the cutting teeth which upon drilling directly contact the rock,said wear resistant layer and said supporting layer being isostatically compacted hot which combined are of substantially 99% density,said layers having a solid bond therebetween providing a drill bit of superior mechanical properties including high resistance to wear and chipping.

Abstract: The high speed seal is an integral metal-to-metal type seal that, in its initial application, acts as a regular resilient O-ring. As the seal begins to operate, a protruding circular resilient lip adjacent the metal sealing ring provides an initial seal and, as the seal continues to function over a length of time, the resilient portion wears away and metal-to-metal contact begins to be made. Thus the seal gradually converts from a standard O-ring type of seal to a lapped-in metal-to-metal seal during operation of the bit.

Abstract: A rolling cone cutter earth boring bit is provided having a pair of radial facing thrust bearing surfaces bounding the pilot pin of the journal and the pilot pin cavity on the cone. The thrust bearing surface of the cone defines a plurality of slots open to, and angled forwardly from, the pin cavity, and terminating within the annular bearing area. The bearing surfaces are, upon assembly, lubricated with a "smear grease" which, under drilling operation works its way to the radially outermost area of the bearing surfaces leaving the bearing area adjacent the pilot pin generally depleted of lubricant. The slots, being closed on the outer end and having radially inwardly impelling force, scrape the outwardly migrated lubricant from the journal pin thrust surface and direct it back toward the pilot pin area for redeposition to replenish lubricant in the radially inner area of the bearing.

Abstract: A rolling cone cutter earth boring bit is provided having a pair of facing thrust bearing surfaces, one such surface on the rolling cone and the other surface on the journal pin. The latter surface defines an annular groove which has separate arcuate segments thereof filled with a hardfacing material and machined to provide a complimentary engaging surface with the cone thrust bearing surface. The spaces in the groove between the hardfacing segments define pockets providing lubricant reservoirs and debris traps for the immediately adjacent thrust bearing surfaces.

Abstract: A dynamic seal is disclosed for sealing between a rotating cutter and a drill bit journal in an underground formation drilling bit, which seal utilizes a static elastomeric seal ring abutting a metal seal ring having a dynamic sealing face.

Abstract: A rotary drill bit comprising at least one roller cutter (12) which is rotatably supported over bearing means (14, 15, 16) and provided with cutting means (13). The bearing means comprises a radial friction bearing (16) with a bearing element (25) of wear resistant material, such as hard metal. In order to improve the surface contact between the bearing element (25) and the inner bearing surface (27) in the roller cutter (12), and in order to remove impurities from the cooperating bearing surfaces a longitudinal groove (30) is provided in the bearing element (25). The fluid primarily supplied for flushing the groove (30) is secondarily used to cool the bearing element (25).

Abstract: A rolling cutter drill bit is disclosed which utilizes a plurality of rolling cutters each rotatably mounted on a lug member having a downwardly extending bearing journal. Each bearing journal has a ball bearing race formed therein for receiving a series of ball bearings which also seat in a mating ball bearing race formed in the rotatably mounted cutter. The ball bearings are arranged to share the axial loading placed on the rolling cutter and primarily lock the cutter on the journal shaft. Each journal is further provided with a unique large thrust surface across the downward end of the bearing shaft and generally perpendicular to the radial bearing surface. The large flat perpendicular thrust surface eliminates the need for a standard pilot pin structure normally found in rolling cutter bits.

Abstract: An automatic wear compensating seal device is provided for forming a seal between first and second members. An elastic sealing member is positioned between the first and second members such as that the elastic force of the sealing member holds the sealing member against at least one of the first and second members. An inclined surface is provided on the first member, the surface being inclined at acute angle with respect to the plane of sealing member. The inner peripheral surface of the sealing member contacts the first member on the inclined surface thereof to form a seal therebetween and the reaction force caused by the elastic force of the sealing member on the inclined surface holds the sealing member in contact with the second member to form a seal therebetween. Further a rotary drill bit is provided which includes the improvement of an automatic compensating seal device.

Abstract: Compositions, and the process of their use, for extending the useful life of machine elements wherein two metal bearing surfaces are in contact one with the other, or with a working surface, e.g., drill bits, gear faces, bearings, sleeves, bushings, ball-joints, journalled shafts, and the like. The compositions are formed by use of a carrier, e.g., as an oil, grease, synthetic, or the like, by the addition thereto of reactants comprised of an electron donor metal, or compound, and a decomposable plating-metal bearing compound, one or both of which reactants is encapsulated or coated to separate the reactants.

Abstract: A flow stream of drilling gas in a gaseous drilling fluid circulation drilling system is separated from that drilling gas supplied to the drill string, and the flow stream is reduced in temperature prior to supplying the flow stream to a drilling tool component to be cooled. A heat exchanger is employed to remove heat from the flow stream, and a second separate flow stream of drilling gas is directed over the heat exchanger to remove the heat. The temperature of the second cooling stream is reduced by thermodynamic effects. Various drilling tool components may be cooled, including bearing means operative between two relatively movable parts, a seal assembly operative to seal lubricant between two relatively moving parts, and cutter elements of a drag-type drill bit. The seal assembly includes a flange-like projection member and a fluid conducting conduit in thermal transferring relationship with the projection member.

Abstract: A rolling cone cutter earth boring bit is provided with a sealing system that results in the seal being squeezed uniformly around the seal circumference during drilling. The bearing pin seal surface is machined eccentrically to the bearing pin by an amount equal to the radial clearance of the bearing. The bearing pin seal surface is machined about an axis that is offset from the central axis of the bearing pin in the direction of the unloaded side of the bearing pin. When the bit is drilling and the bearing pin is loaded the seal will run on an axis concentric with the axis of the seal surfaces of the bearing pin and the rolling cutter and will see uniform squeeze around its circumference.

Abstract: The bearing surface of a cone cutter bit is hard-faced by forming a substantially cylindrical bearing structure on the drill bit leg having a diameter less than that of the mating bearing on said cone cutter. A cylindrical tubular sleeve of hard low friction metal which has an inner diameter greater than the diameter of said cylindrical bearing structure is inserted over said bearing structure, and a disc is placed over the end and inside said tubular metal sleeve. Solder is flowed between the sleeve and the disc to attach the sleeve and disc to the bearing structure to create a hard-faced bearing. Openings can be preformed in the sleeve or disc to match fluid cooling holes in the drill bit leg.

Abstract: A rotary rock bit is described having a one piece bit body with a plurality of legs extending downwardly therefrom. Each leg includes an annular bore extending therethrough for receiving the mounting end of a separate journal pin. Each journal pin also includes a bearing end for rotatively supporting a cone type cutter. Cone retention members are operatively engaged to each journal pin for retaining the cone cutter on each journal pin. In assembly the cone cutters, with the retention members contained therein, are positioned interior of the legs of the one piece bit body in their operative location. The journal pins are then inserted through the leg bores until they extend into the cavities of the respective cone cutters. Each journal pin is then secured to a respective leg and the retention members are secured to the journal pins, preferably by electron beam welding techniques.

Abstract: A drilling fluid roller reamer-stabilizer includes a tubular body having threaded pin and box connectors at each end adapted to be connected in a drill string and providing a fluid passage connecting the upper part of the drill string with the lower part. Rollers having integral pins at their ends are mounted in pockets in the sides of the body. The pins extend into holes in arcuate cross section bearing blocks received in correlative sockets in the body at the ends of the pockets. Each block makes an interference fit with the sockets in the body. Tool access passages allow a tool to be inserted behind each block to drive or pry it out. Slotted, resilient bearing sleeves are provided in the holes in the blocks where the roller pins are received. The sleeves extend beyond the holes toward the rollers to take axial thrust. Flanges on the ends of the sleeves provide additional thrust area.

Abstract: A drill string reamer-stabilizer includes a main body adapted to be connected as an element of a rotary drill string. Individual bearing shafts are mounted axially along the exterior of the main body supporting roller cutters that engage the wall of the borehole. Seal units are positioned around each bearing shaft between each roller cutter and bearing shaft to define a lubricant space. The seal units retain lubricant in the lubricant space and prevent contaminating fluid and materials in the borehole from entering the lubricant space. At least one seal unit comprises an annular cup-shaped elastomer seal member with an annular lip mounted in an annular seal gland in the roller cutter. The seal gland has an inner side adjacent the lubricant space and an outer side exposed to the fluid and materials in the borehole.

Abstract: A bearing assembly, for a drive shaft connected to an in-hole motor rotor to drive a bit and a housing connected to the motor stator has sets of oppositely acting thrust bearings having corresponding members of bearings and parts at opposite sides of a thrust member on the shaft. Plural sets of thrust bearings are shown between spaced radial bearings to optimize load distribution.

Abstract: A rotary drill bit having a drill bit body and at least one trunnion projecting from the drill bit body and a rotary cutter supported on at least one radial roller bearing on the trunnion. The rolling elements of the bearing are guided on at least one axial end facing the drill bit body in an outer bearing race groove incorporated in the bore of the rotary cutter. The inner bearing race groove is formed on the trunnion for the rolling elements of the radial roller bearing. At least one filling opening is provided which extends through the drill bit body and trunnion and is essentially axially oriented having one terminal end adjacent the inner bearing race groove and at least one filler piece for sealing the opening.

Abstract: A rolling cone cutter earth boring bit is provided with an improved lubrication system including an eccentric bearing surface and spaces for lubricant. At least one cantilevered bearing pin extends from the arm of the bit. A rolling cone cutter is rotatably mounted on the bearing pin. The outer bearing surface of the bearing pin is provided with a pair of grooves. The unloaded side surface of the outer bearing surface is formed by eccentric machining. Reduced clearance is provided between the rolling cone cutter and the load side surface and increased clearance is provided between the rolling cone cutter and the unloaded side surface. The pair of grooves and the increased clearance serve as a lubricant reservoir in close proximity to the load side of the bearing pin.

Abstract: A cure-in-place process which allows a rubber seal element to be deformed to its service configuration before it is cross-linked and, hence, is a plastic and does not build up internal stress as a result of the deformation. This provides maximum residual strength to resist the differential pressure. Furthermore, the process allows use of high modulus formulations of the rubber seal element which would otherwise crack if cured and then deformed to its service configuration, resulting in a seal which has better gap bridging capability. Basically, the process involves positioning an uncured seal element in place, deforming it to its service configuration, heating the seal element, curing it in place, and then fully seating the seal.

Abstract: Disclosed herein is an earth boring bit of otherwise conventional construction except for the bearing and cutter retention. A snap fit ring is used to retain the cutter, the grooves that receive the ring and the ring construction being such that the ring is forced into the retainer groove when the cone is thrust inward. The ring cannot therefore accidentally return to its assembly position to permit cutter loss. This enables the use of exclusively frictional bearings and retainer means of exceptional strength and reliability.

Abstract: A rolling cone cutter earth boring bit is provided with a load carrying bearing surface that can be renewed during the earth boring operation. A canister bearing element is positioned between the bearing pin and the rolling cone cutter. The rolling cone cutter rotates about the canister bearing element in a first direction during normal drilling operations. The canister bearing element has directional stops on its inside surface. These directional stops engage directional stops on the bearing pin and prevent rotation of the canister bearing element during normal drilling operations. The bearing surface can be renewed by reversing the direction of cutter rotation thereby disengaging the canister bearing element from the directional stops and allowing it to rotate in the opposite direction until a new bearing surface is in the load area.

Abstract: A sealing system for a rotary rock bit retains lubricant inside the bit and acts as a barrier to the pulverized cuttings and other materials in the borehole to prevent the materials from entering the bearing area through the cone mouth opening of the rolling cone cutter. A protecting washer is positioned outside of an O-ring seal element in the gap between the base of the rolling cone cutter and the body of the earth boring bit. This protects the O-ring seal element from the hostile drilling environment and increases seal life. During assembly of the bit, a gauging station is established to measure the size of the gap that will exist when the rolling cone cutter is installed on the bit body. Protecting washers are provided in numerous thicknesses. Upon determining the size of the gap, a washer is selected that will allow the gap to be narrowed to a size that will restrict passage of most of the abrasive particles found in the drilling fluid.

Abstract: An in-hole, fluid driven motor has a stator and a rotor to drive a bore hole drilling bit. The bit is connected to the rotor by a drive shaft rotatable in a bearing housing connected to the stator, and drilling fluid flows through the drive shaft and exits through the bit. Radial and thrust bearings include a first bearing which transmits thrust from the housing to the bit, while drilling, and a second bearing which transmits thrust to the housing from the shaft, when the bit is off the bottom of the hole. An adjustable lock nut is connected to the drive shaft and a ported cap which connects the drive shaft to a connecting rod coupled with the rotor, and permits alternate unloading of the first and second bearings and the elimination of increased bearing tolerances as wear occurs.

Abstract: In a drilling bit, a cone shaped cutter is rotatably mounted on a spindle on anti-friction bearings and on a friction bearing in the nose of the spindle. A passage is formed in the exterior cylindrical surface of the spindle nose in the load bearing zone. This passage is connected to a radial passage on the end or thrust bearing surface of the spindle, and the center of the thrust bearing surface communicates with a weep hole in the nose of the cutter. Cooling fluid is ducted through the spindle and through these passages to provide cooling directly in the area where the generated heat is the greatest and fluid flow a minimum in previous constructions.

Abstract: Lubricant is circulated from a lubricant reservoir to the bearings of a rotary rock bit and back to the lubricant reservoir by a lubricant circulation system that is operated by rotation of the cone cutter upon the bearing pin of the bit. A seal is positioned between the rolling cone cutter and the arm of the bit to maintain lubricant in the bearing area and to prevent fluid and materials in the borehole from entering the bearing area. A lubricant reservoir is located in the bit body. A first passage connects the lubricant reservoir with the bearing area to channel lubricant from the lubricant reservoir to the bearing area. A second passage extends from the bearing area to the lubricant reservoir to allow lubricant to be channeled back to the lubricant reservoir.

Abstract: A roller on reamer's rollers are rotatably mounted on shafts whose ends are supported by blocks inserted in the reamer body. One end of each shaft is welded, pinned, or otherwise nonrotatably anchored to its mounting block. Each block makes an interference fit with the body socket in which it is disposed. The blocks are stepped or tapered for quick release. Access openings to the backs of the blocks facilitates knockout. Knockout of the stepped blocks is achieved by wedge means.Drilling mud may have access to contacting surfaces of rollers and shafts to lubricate same. Protective seal means may be provided between each roller and shaft at the upper ends thereof so that the mud must flow upwardly to reach the space between shaft and roller and dense solids will be excluded by gravity. Grease lubrication may be provided, e.g. in conjunction with roller shafts mounted in stepped blocks, the rollers being sealed to the shafts at both ends.

Abstract: A seal acts as a barrier to the drilling fluid, pulverized cuttings and other materials in a borehole preventing the materials from entering the bearing area of a rolling cone cutter earth boring bit and retains lubricant inside the bearing area. A rolling cone cutter is rotatably mounted on a cantilevered bearing pin extending from the bit body. A "Z" seal is positioned between the cutter and bearing pin. An outer rigid seal ring is positioned around the bearing pin. The outer rigid seal ring is split to allow radial expansion and contraction. An inner rigid smaller diameter seal ring is positioned around the bearing pin. The inner rigid seal ring is also split to allow radial expansion and contraction. An elastomer ring is located between the inner and outer rigid rings and affixed to the rigid rings.

Abstract: A rotary rock bit is described having a plurality of legs extending downwardly from the main bit body. Each leg further includes an inwardly extending journal pin for rotatively supporting a cone-type cutter. An annular thrust member is provided for axially retaining the cutter onto the journal pin. In one embodiment the thrust member is adapted to extend into an annular groove formed in the journal pin with the other radial surface thereof engaging an inner annular surface of the cutter. The radial surface of the thrust member is then welded to cutter by an electron beam process. An access aperture is provided in the journal pin and leg to enable the electron beam to pass therethrough and strike the thrust member and cutter. During this operation, the cutter is rotated along with the thrust member across the access aperture to create a 360.degree. weld therebetween. In another embodiment, an annular groove is formed in the cutter cavity for receiving the thrust member.

Abstract: A rolling cone cutter earth boring bit is provided with a seal assembly for sealing the bearings of the bit from the abrasive materials in the borehole and retaining lubricant within the bearing area. A rolling cone cutter is rotatably mounted on a cantilevered bearing pin extending from the bit body. A first seal receiving surface is located on said bearing pin. The first seal receiving surface has a first corner. A second seal receiving surface is located on said rolling cone cutter. The second seal receiving surface has a second corner. The seal assembly includes first and second seal units. The first seal unit comprises a first annular substantially rigid ring and a first substantially resilient ring positioned between said bearing pin and said rolling cone cutter. The first resilient ring is positioned in said first corner. The second seal unit comprises a second annular substantially rigid ring and a second substantially resilient ring positioned between said bearing pin and said rolling cone cutter.

Abstract: A sealed rotary rock bit is disclosed in which a combined manual venting and pressure relief system is located within the lubrication reservoir of the rock bit. The seal rotary rock bit comprises a main bit body having a plurality of legs extending downwardly therefrom. Each leg has a rolling cone cutter rotatively mounted thereon. A lubrication system is provided in each leg to provide lubricant to the bearing area between the cutter and the leg. The lubrication system includes a reservoir of lubricant communicating via passageways with the bearing area. The reservoir further includes a rubber boot molded around a metal stiffener sleeve. A cover cap is attached to the rubber boot. The rubber boot is in the form of a resilient membrane and is exposed through the cover cap to the exterior of the rock bit and through the passageways to the interior of the lubricated bearing area. The vent and pressure relief system comprises an annular seat formed in the wall of the reservoir.

Abstract: Rotary earth boring bits according to the present invention and method of assembly thereof allow development of a rotary earth boring bit construction of low cost nature and having exceptionally good wear life. The drill construction promotes the use of optimum bearing materials for rotary support of the cutters of the drill thereby promoting exceptionally good service life. Additionally, the bearing of each cutter assembly may be lubricated so as to further enhance the service life of the drill. Assembly may be accomplished at low cost by taking advantage of dimensional changes of the parts responsive to heating or cooling. The drill cutter may be heated to increase the dimension of the bearing cavity formed therein while the bearing and its support spindle may be cooled to reduce the external dimension of the bearing. Following assembly of the bearing and spindle to the cutter a tight retention fit will develop between the bearing and cutter as these parts approach normal temperature.

Abstract: A rotary drill bit having a rolling cutter mounted on a journal by means of internal, anti-friction bearings is provided with a sealing ring between the journal and cutter. The journal and cutter have facing, circumferential surfaces of which one surface is provided with a groove facing the other surface. One or more annular sealing rings are spring pressed against and carried by the other surface and extend into and seal against the annular groove to seal the interior bearings from contamination. The one or more rings are forced under spring pressure into the annular groove when the cutter is mounted to the journal, the ring or rings returning under spring pressure to press against and be carried by the other circumferential surface while yet extending into and sealing against the groove.

Abstract: A rotary drill bit is provided with confronting large hard annular bearing surfaces on the journal-bearing body and on the journal-mounted conical cutter of the bit. The hard surfaces are generally normal to the axis of rotation of the cutter to bear axial loads, and provide a large bearing area resulting in relatively low unit pressures on the bearing surface. The hardness of the bearing surfaces should be greater than the hardness of the rock or other material being drilled. The journal and cutter may have confronting but spaced inner hard bearing surfaces which come into sliding, bearing contact with each other as the first-mentioned bearing surfaces are worn down. Cooling means are provided to cool the bearing surfaces, and an internal ball bearing and race assembly permits limited movement of the cutter axially on the journal to allow for wear of the bearing surfaces and to eventually bear axial loads. Also described is a nozzle means for sweeping cuttings to the periphery of the drill hole.

Abstract: A partially solid head bit having a flow passage therethrough located at approximately the center of the bit is shown. The bit is designed for use in conjunction with a hammer action drilling apparatus. The flow passage extends through a shank of the bit to the bottom thereof. Surrounding the shank is a substantially hemispherical spiraled burr having an opening therethrough. The burr pushes against a shoulder of the shank during drilling. The mating surfaces of the shank and burr are lubricated by a suitable oil reservoir. On spirals of the burr and on the lower end of the shank are mounted hardened inserts for impacting against and breaking up the formation through which the bit may drill. The bottom of the shank may be even with, extend through, or be recessed with respect to the lower edge of the burr. The shank is angled a few degrees off the centerline of the drilling string to cause a wobbling action upon rotating the drill bit.

Abstract: A sealing arrangement for a rolling cutter designed to protect the antifriction bearings disposed between a support shaft and a rotatable outer body of the rolling cutter. A sealing arrangement is provided comprising at least two seal means located outward from the antifriction bearing of a rolling cutter and further comprising a cavity means between the two seal means so that flushing coolant, fluid or grease may be injected into the sealing arrangement and, when injected, will carry heat, dirt and other contaminants outward and away from the interior of a rolling cutter thereby preventing damage to the antifriction bearings and the seal means located nearest to the antifriction bearings.

Abstract: An earth boring drill employing roller cutters is provided with a seal in a peripheral groove to inhibit ingress of detritus into the cutter bearing area and egress of lubricant therefrom. The shape of the seal is such that its cross section is not overly compressed or displaced when in operating position, thus preventing undue compression set, wear and heating of the seal. A preferred seal has a greater radial dimension than axial dimension by a ratio of at least one-and-one-half to one to conserve bearing space and to provide the necessary flexibility to accommodate the various movements of the cutter relative to the shaft upon which it is rotatably mounted. The roller cutter has a counterbore fitting over a short cylindrical boss from which the shaft extends on which the cutter is mounted. This provides a tortuous passage restricting ingress of detritus and substantially improved life of the drill bit.

Abstract: This invention relates to hard metal radial bearings particularly suitable in connection with thrust bearings which are lubricated by erosive fluids passing through the radial bearings as are employed in down-hole drilling motors.

Abstract: A self-advancing conical boring tool with frusto-conical roller cutters rotatably mounted to a tapered frame by means of self-aligning spherical roller bearings. Each roller cutter is constrained within a pair of spherical roller bearings for free rotation about an axis that is both oblique and skewed relative to a longitudinal axis of the frame.

Abstract: An earth boring auger having a shaft and helical flights thereon and a plurality of disc cutters mounted below the flights to engage the formation before it is engaged by the flights.

Abstract: A sealing system for a rotary rock bit acts as a barrier to the pulverized cuttings and other materials in the borehole and prevents the materials from entering the bearing area through the cone mouth opening of the cone cutter. The bearing rollers are substantially captured in a groove machined into the cone cutter. This allows a seal unit to be located at a substantial distance from the hostile drilling environment and increases seal life. The shirttail portion of the bit body and the base of the cone cutter cooperate to retard materials in the borehole from contacting the seal unit. The sealing system is provided without reducing the bearing capacity of the bit's bearing system.

Abstract: A cutter with replaceable cutting elements is adapted to be mounted upon the rotary head of an earth boring machine or upon the body of an earth boring bit. The cutter is used in conjunction with an earth boring machine that functions to form circular kerfs in the formation being bored to fracture rock between a proximate pair of kerfs in a manner to cause fragments of the formation to be separated from the formation being bored. At least one annular cutting ring is mounted on the periphery of the cutter body for contacting the formations and forming a kerf therein. The cutting ring is in the form of a pair of substantially semicircular disk elements that fit upon the periphery of the cutter body. A corresponding pair of semicircular locking elements with taper surfaces are positioned in overlapping relation to the disk elements. The locking elements are securely bolted to the cutter body and insure that the disk elements remain in the proper position for the earth boring operation.

Abstract: a cutting element for mounting in a rolling cone cutter of a rock drill bit has a notch in the periphery of its base for improved retention of the cutting element in the rolling cone cutter. The longitudinal axis of the notch is essentially transverse to the direction of insertion of the cutting element into the rolling cone cutter. To maximize the effectiveness of the notch in improving retention of the cutting element, preferably the notch is sharp lipped.