Abstract: A water separator valve assembly is provided, including: a main body, including a chamber, first and second outlet pipe and an inlet pipe; a control assembly, including a valve member disposed in the main body and an elastic plug, the valve member including a base disposed in the chamber and a receiving portion disposed on the base, the base including inlet holes respectively in communication with an inlet channel in the main body, the receiving portion including a receiving hole and a through hole, the elastic plug being disposed in the receiving hole, the elastic plug being elastically abutted between a bottom wall of the receiving hole and an inner wall the chamber; wherein the valve member is rotatable relative to the main body to drive the elastic plug to seal the first outlet channel or an second outlet channel in the main body.

Abstract: Providing accurate speed and rotation of a motor of a drilling assembly allows accurate monitoring of a drilling operation, for example, direction of drilling, rate of penetration, vibration, and stability of the drilling assembly. A bi-stable magnetic device is used to provide better control of torque and rate of penetration and prevention of slip-stick issues. One such device is a downhole motor that includes a stator and a rotor with a magnetic blade. The magnetic blade includes at least one of a magnetic edge, a magnetic surface, and a magnetic core, or is entirely or partially magnetic. A sensor is positioned in the stator to detect the passing of the magnetic edge of the blade of the rotor. Detection of one or more magnetic blades may provide rotational speed or other status information of the drilling assembly.

Abstract: A drill string stabilizer for use in a well bore includes a tubular body with a stabilizer axis, a first roller including a first roller axis spaced apart from the stabilizer axis of the tubular body, and at least a second roller spaced longitudinally apart from the first roller, the at least a second roller including a second roller axis spaced apart from the stabilizer axis of the tubular body. The first roller is angularly offset from the at least the second roller around a circumference of the tubular body.

Abstract: A rotary downhole tool, for example in the form of a drill bit, is described that includes a tool body, the body defining a gauge region, and at least one gauge roller rotatably mounted to the body.

Abstract: Drill bits and methods relating thereto are disclosed. In an embodiment, the drill bit includes a body having a plurality of legs each having a lower section that has a leading surface and a trailing surface. A plurality of cone cutters are each rotatably mounted to the lower section of one of the legs, each having a cone axis, and including a first plurality of cutter elements arranged about the cone axis such that each is shear the formation when the body is rotated about the bit axis.

Abstract: A sealed bearing rock bit has a plurality of legs with journals formed to extend inward and downward at the end of the legs. Each of the legs has a last machined surface located adjacent to the bases of the journals and into which a seal groove is formed which circumscribes the respective journal. Cutters are rotatably mounted to respective ones of the journals, with back faces of the cutters located adjacent to respective ones of the last machined surfaces. The back faces of the cutters have annular-shaped protrusions which extend from said back faces and protrude into the seal grooves beyond the last machined surfaces of said journals extending an annular-shaped seal surface which is engaged by a seal disposed in the seal groove, leaving more of the interface space between the journal and the cutter for larger roller bearings.

Abstract: An instrumented cutting element, an earth-boring drilling tool, and related methods are disclosed. The instrumented cutting element may include a substrate base, a diamond table disposed on the substrate base, a sensor disposed within the diamond table, a lead wire coupled to the sensor and disposed within a side trench formed within the substrate base, and a filler material disposed within the side trench. The earth-boring drilling tool may include securing the instrumented cutting element to a blade of a bit body. A related method may include forming the instrumented cutting element and earth-boring drilling tool.

Abstract: A drilling system for a mining machine, the mining machine including a frame and a boom moveable coupled to the frame and a drill string positioned in a blast hole. The system includes an air compressor, a drill bit connected to the air compressor configured to receive low pressure air. The drill bit has a nozzle free drilling body, three sealed rotating cones, each cone with a plurality of cutting elements. Each cone having a sealed bit bearing assembly with diaphragm free lubricant spaces. A single central air conduit in the drilling body providing continuous high flow rate low pressure air from the drill string configured to strike the plurality of outer surfaces of the sealed rotating cones upon exit of the high flow rate low pressurize air from the single central air conduit cooling the sealed bit bearing assemblies. A relief conduit is used.

Abstract: Drill bit assembly imaging systems and methods are disclosed herein. An example method disclosed herein includes directing light conveying an image of a target through a portion of a drill bit assembly and capturing the image via an image sensor disposed inside the drill bit assembly. The example method also include determining drilling information based on the image via an image processor disposed inside the drill bit assembly.

Abstract: A hybrid-type earth boring drill bit is described having fixed cutting blades and rolling cones with cutting elements, wherein the rolling cones are associated with a spindle assembly that may be optionally divorced from the head pin assembly, and which includes bearing members that further include a plurality of polycrystalline diamond elements.

Abstract: An ejector or jet pump is provided for use in the drilling of wells to prevent the total fluid pressure at the bottom of the borehole from reaching a level which constitutes a risk of cracking the rock or sediment being drilled, thus resulting in leakage and circulation failure. The pump is placed between the drill bit and the drill string and provided with nozzles directed in such a way that low pressure is established externally at the drill bit. The pump is operated by the drilling fluid which is supplied in the normal way through the drill string. The pressure difference across the pump is used to draw a secondary flow of drilling fluid from the borehole through internal bores in the pump to the nozzles in the drill bit. This fluid flow provides necessary cleaning of the drill bit and drilling surface.

Abstract: A cutting element assembly includes a rotatable cutting element having an axis of rotation extending axially therethrough, a cutting face and a body extending axially downward from the cutting face, at least one retention mechanism disposed adjacent to the rotatable cutting element, and a first magnet disposed at a back face of the rotatable cutting element.

Abstract: A drill and a separator apparatus and a method of prolonging bearing life are described, the separator apparatus being suitable for separating an air/water mixture into discrete air and water streams during drilling of a blast hole. The separator apparatus includes a separator body which is adapted to be installed at a distal or lower region of a drill string and when installed at the distal or lower region forms one or more separation chambers or reservoirs, each separation chamber or reservoir comprising an inlet adapted to receive the air/water mixture, a first outlet in fluid communication with a drill bit for releasing air thereto and a second outlet in fluid communication with a wall of the blast hole and disposed in the distal or lower region of the drill string to release water separated from the air/water mixture in a region adjacent the drill bit.

Abstract: The roller cone is retained to the head with axial play taken out of the bearings with a tension rod that is tensioned from the rear of the head and away from the nose bearing region of the head allowing greater resistance to loading in the region of the nose bearing and a reduction in critical stresses. The tension rod has a flat and is oriented for tightening so that the flat faces grease passages to allow grease to gain access to the bearings through the bore for the tension rod and otherwise fill the bore so the tension rod actively supports loading in the head bearing. The nose bearing can be separately supported to the cone directly with a retainer threaded to the cone or a spacer between the bearings can be used so that tensioning of the rod takes out the axial play in both bearings with force transmitted to a retainer at the back of the cone.

Abstract: An improved cutter for fixed cutter drill bits includes a base portion with a longitudinal axis that extends through a center of the base portion and a cutting face which is generally centered with the base portion. The cutting face has a periphery edge geometry comprising a first arcuate segment and a second arcuate segment spaced apart and arranged opposite each other with linear edge segments disposed there between forming sides of the cutting face. The cutting face spans a maximum edge-to-edge dimension L in a first direction that corresponds to a major axis of the cutting face. The cutting face spans a maximum edge-to-edge dimension W in a second direction, which is perpendicular to the first direction, and W is less than L.

Abstract: In one aspect of the invention a degradation drum comprises a generally cylindrical body comprising inner and outer diameters. At least one degradation assembly is disposed on the outer diameter and it comprises a holder and a pick shank secured within a bore of the holder. At least one lubricant reservoir is disposed within the inner diameter and is in fluid communication with the bore of the holder through a fluid pathway. In some embodiments, the lubricant reservoir maintains a fluid pressure on the pick shank.

Abstract: Methods and apparatus for maintaining lubrication of rolling cone cutters mounted on journal pins. Embodiments comprise a rotating cone disposed on a journal pin and forming a journal gap there between. A cylindrical journal sleeve is disposed in the journal gap. The journal sleeve has a longitudinal gap forming opposing end portions, which are continuously contoured. A lubrication port is disposed in the journal pin and in fluid communication with a lubrication supply. The lubrication port has an outlet located in a recess in the journal gap. Each end of the recess comprises a transitioning surface extending between the bottom of the recess and the outer surface of the journal pin to prevent sharp transitions. In certain embodiments, the journal pin may comprise two or more lubrication ports, each located in a recess with transitioning surfaces.

Abstract: An earth boring bit has rotating cones with two lubricant passages to increase bearing capacity and cause lubricant circulation. A lubricant reservoir in the body supplies lubricant to passages between the cone and bearing pin. A pressure compensator equalizes lubricant pressure to the exterior of the bit. A first passage leads from the reservoir to the upper side of the bearing pin. A second passage leads from the reservoir to the bearing pin at a point from 185 degrees to 225 degrees as seen from an inner end of the bearing pin. This point is located in a diverging region 51d of an annular clearance surrounding the bearing pin.

Abstract: A roller-cone rock bit in which the compensation reservoir is integrated with a hydrostatically-asymmetric seal, such as a V-seal, which provides pressure relief. This seal not only relieves overpressure during filling, and when the grease thermally expands as the bit first goes downhole, but also compensates transient overpressures during operation.

Abstract: An improved drill bit for use in drilling operations in a wellbore comprising a bit body including a plurality of bit legs, each supporting a rolling cone cutter, a coupling member formed at an upper shank portion of said bit body, at least one sensor for monitoring at least one condition of said improved drill bit during drilling operations, and an electronics bay portion defined in-part by said upper shank portion of said bit body for housing at least one monitoring circuit.

Abstract: A roller cone drill bit is disclosed which includes at least one roller cone rotatably mounted to a bit body. The bit body includes therein a lubricant reservoir adapted to supply lubricant to bearings on which the roller cone rotates about the bit body. The bit includes a sensor adapted to detect drilling fluid contamination of the lubricant. The bit includes a processor/transmitter operatively coupled to the sensor and adapted to communicate signals corresponding to detected contamination.

Abstract: A drill bit for use in a borehole at least partially containing drilling fluid includes a bit body having at least two bit components, including at least one leg, the leg having a journal segment, and a roller cone rotatably mounted upon the journal segment and forming at least one bearing cavity therebetween. Also included is an annular primary seal disposed between the leg and the roller cone, an annular secondary seal disposed between the leg and the roller cone and between the annular primary seal and the borehole and an annular space disposed between the annular primary seal and the annular secondary seal, the annular space at least partially containing fluid and being in substantially absolute fluid isolation from the bearing cavity and a conduit for permitting the flow of fluid from the annular space to the borehole. The annular secondary seal may be primarily elastomeric and the means for permitting the flow of fluid may further permit the flow of fluid from the borehole to the annular space.

Abstract: A drill bit for use in a borehole at least partially containing drilling fluid includes a bit body having at least two bit components, including at least one leg, the leg having a journal segment, and a roller cone rotatably mounted upon the journal segment and forming at least one bearing cavity therebetween. Also included is an annular primary seal disposed between the leg and the roller cone, an annular secondary seal disposed between the leg and the roller cone and between the annular primary seal and the borehole and an annular space disposed between the annular primary seal and the annular secondary seal, the annular space at least partially containing fluid and being in substantially absolute fluid isolation from the bearing cavity and a conduit for permitting the flow of fluid from the annular space to the borehole. The annular secondary seal may be primarily elastomeric and a passage for permitting the flow of fluid may further permit the flow of fluid from the borehole to the annular space.

Abstract: Annular seals of this invention comprise an elastomeric seal body that is configured to fit within a seal gland of a rock bit. The seal comprises a first seal surface, for providing a seal along a dynamic rotary surface formed between the seal body and one portion of the rock bit, and a second seal surface, for providing a seal between the seal body and another portion of the rock bit. The annular seal further comprises an extrusion prevention member that is positioned adjacent a surface of the seal body between the first and second seal surfaces. The extrusion prevention member can be integral, partially-attached, or independent of the seal body. The extrusion prevention member is preferably formed from a material having a hardness that is greater than that of the seal body. The member is positioned along the seal body at a location adjacent a groove, formed between opposed members of the rock bit, to act as a physical barrier to prevent the seal from being extruded therethrough.

Abstract: A bit is provided having at least one leg extending downwardly and inwardly from the bit body. A cutter cone is rotatably mounted on a shaft extending inwardly from the lower portion of each leg. The annular space defined by the base of the shaft and the inner surface at the base of the cone forms a seal gland. An elastomeric o-ring sealingly engages an inner surface of the cone and a first rigid ring which rotates with the o-ring and cone. The o-ring energizes the first rigid ring for sealingly engaging a second rigid ring mounted to the leg of the bit near the base of the shaft. The second rigid ring is secured to and seals against a surface at the base of the shaft and is held stationary relative to the surface. A lubricant passage for lubricating the seal is pressurized by the drilling fluid pressure in the center of the bit body.

Abstract: A drill bit for use in a borehole at least partially containing drilling fluid includes a bit body having at least two bit components, including at least one leg, the leg having a journal segment, and a roller cone rotatably mounted upon the journal segment and forming at least one bearing cavity therebetween. Also included is an annular primary seal disposed between the leg and the roller cone, an annular secondary seal disposed between the leg and the roller cone and between the annular primary seal and the borehole and an annular space disposed between the annular primary seal and the annular secondary seal, the annular space at least partially containing fluid and being in substantially absolute fluid isolation from the bearing cavity and means for permitting the flow of fluid from the annular space to the borehole. The annular secondary seal may be primarily elastomeric and the means for permitting the flow of fluid may further permit the flow of fluid from the borehole to the annular space.

Abstract: A rock-crushing rotary drill bit includes a body having a rock-crushing roller rotatably mounted thereon by bearings. The body includes a first flushing channel for conducting flushing fluid to flush the bearings, and a second flushing channel for discharging flushing medium outside of the bit body to flush away cuttings. The second flushing channel terminates in a discharge recess which defines a linear center axis. A nozzle is disposed at a downstream end of the discharge recess, and a valve element is disposed at an upstream end of the discharge recess. The valve element is spring-biased for closing the discharge recess, the valve element being openable against the spring bias in response to a sufficient pressure build-up of flushing medium within the second flushing channel. The valve element includes a guide structure for guiding the valve element for linear movement along the center axis of the discharge recess.

Abstract: A drill bit for use in a borehole at least partially containing drilling fluid includes a bit body having at least two bit components, including at least one leg, the leg having a journal segment, and a roller cone rotatably mounted upon the journal segment and forming at least one bearing cavity therebetween. Also included is an annular primary seal disposed between the leg and the roller cone, an annular secondary seal disposed between the leg and the roller cone and between the annular primary seal and the borehole and an annular space disposed between the annular primary seal and the annular secondary seal, the annular space at least partially containing fluid and being in substantially absolute fluid isolation from the bearing cavity and means for permitting the flow of fluid from the annular space to the borehole. The annular secondary seal may be primarily elastomeric and the means for permitting the flow of fluid may further permit the flow of fluid from the borehole to the annular space.

Abstract: A drill bit for use in a borehole at least partially containing drilling fluid includes a bit body having at least two bit components, including at least one leg, the leg having a journal segment, and a roller cone rotatably mounted upon the journal segment and forming at least one bearing cavity therebetween. Also included is an annular primary seal disposed between the leg and the roller cone and an annular secondary seal disposed between the leg and the roller cone and between the annular primary seal and the borehole. An annular space is defined between the annular primary seal and the annular secondary seal, the annular space at least partially containing fluid and being in substantially absolute fluid isolation from the bearing cavity. The seals are configured to allow the passage of a fluid from the annular space to the borehole. The annular secondary seal may be primarily elastomeric and a passage for fluid from the borehole to the annular space can be included.

Abstract: A roller cone drill bit is shown which includes at least one roller cone rotatably mounted on a journal forming a part of a bit body. The at least one cone having cutting elements disposed at selected locations thereon. The at least one roller cone subtends a journal angle of less than about 35 degrees, and has an offset less than about 0.15 inches. In one embodiment, gage row cutting elements on the at least one roller cone define an oversize angle in a range of about −1.5 to +2 degrees.

Abstract: A roller cone drill bit is disclosed which includes a bit body having at least one leg depending from the bit body. The leg has a journal formed on it at a lower end. The bit body includes an air channel extending at least from an interior of the bit body to the seal area of the journal. A roller cone is sealingly, rotatably mounted on the journal. The cone has a plurality of cutting elements disposed on it. The bit includes a backflow valve disposed in the bit body, so that an intake end of the air channel is disposed upstream of the backflow valve. In one embodiment, the backflow valve is disposed in a connection end of the bit body, and the air channel includes a flow tube extending from the air passage in the bit body to the backflow valve so that its intake end is upstream of the backflow valve.

Abstract: A solid lubricant is added to the internal passages of an air cooled bit such that the air erodes, or ablates, the solid lubricant into the air stream. Compressed air travels down the drill stem to the bit. The air passes through an air tube into the main air passage where the solid lubricant has been placed. As the air passes the solid lubricant, it erodes the solid lubricant. The solid lubricant particles ablated into the air stream travel through the ball passage into the journal air passage and out to the bearing surfaces between the cutter and the journal. The air stream both cools the surfaces and deposits the solid lubricant to reduce the friction between the bearing surfaces.

Abstract: A pressure compensating assembly for use in roller cone drilling bits of the sealed bearing type. The compensating assembly includes a hollow body arranged to fit into a cavity in the bit connected with the lubrication system of the bit and the hollow body includes a normally open lubricant passageway extending therethrough. A seal encircles the body on one side of the lubricant passageway and is arranged to sealingly engage the bit and an elastomeric, cup-shaped diaphragm is located on the body and has a lip arranged to sealingly engage the bit on the other side of the lubricant passageway. The diaphragm having a protuberance on the side of the diaphragm facing the passageway and sized to enter and close the passageway. The body, seal, and diaphragm being assembled into a unitary cartridge for introduction into the bit as a unit.

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

Abstract: A rotary cone rock bit, comprises a bit body including a plurality of legs extending therefrom, each of the legs having an outer surface that includes a leading surface and a trailing surface, a roller cone rotatably supported on each of the legs, a bearing system between each cone and the leg on which it is supported, and a lubricant reservoir in fluid communication with the bearing system. The reservoir can be provided with a wear resistant plug, if desired. In the present bit, the reservoir has at least one opening positioned in either the leg's leading surface, trailing surface, center surface, shoulder surface or some combination of these. Alternatively, the reservoir can be formed inside the bit body, preferably by means of a canister, which can be provided with venting means as desired.

Abstract: A pressure compensating assembly for use in roller cone drilling bits of the sealed bearing type. The compensating assembly includes a hollow body arranged to fit into a cavity in the bit connected with the lubrication system of the bit and the hollow body includes a normally open lubricant passageway extending therethrough. A seal encircles the body on one side of the lubricant passageway and is arranged to sealingly engage the bit and an elastomeric, cup-shaped diaphragm is located on the body and has a lip arranged to sealingly engage the bit on the other side of the lubricant passageway. The diaphragm having a protuberance on the side of the diaphragm facing the passageway and sized to enter and close the passageway. The body, seal, and diaphragm being assembled into a unitary cartridge for introduction into the bit as a unit.

Abstract: In a drill bit which has a reservoir for storing a supply of lubricant, generally grease, a lubricant passage is formed for flow of lubricant from the reservoir to the bearing. A relief port is formed in the drill bit body to connect at least one of the reservoir and the lubricant passage with an outside surface of the drill bit body. A normally-closed relief valve is mounted in the relief port to selectively permit fluid flow through the relief port and protect the lubrication system against changes in pressure, especially increases in pressure on the grease side, such as might be caused by thermal expansion of the grease or the production of off-gases by the grease. The valve is provided in the form of a small screw-in unit capable of separate manufacture and testing and comprises a valve body carrying a flexible diaphragm element. Venting is provided via a puncture in the diaphragm element.

Abstract: A drill bit for use in a borehole at least partially containing drilling fluid includes a bit body having at least two bit components, including at least one leg, the leg having a journal segment, and a roller cone rotatably mounted upon the journal segment and forming at least one bearing cavity therebetween. Also included is an annular primary seal disposed between the leg and the roller cone and an annular secondary seal disposed between the leg and the roller cone and between the annular primary seal and the borehole. An annular space is defined between the annular primary seal and the annular secondary seal, the annular space at least partially containing fluid and being in substantially absolute fluid isolation from the bearing cavity. The seals are configured to allow the passage of a fluid from the annular space to the borehole. The annular secondary seal may be primarily elastomeric and a passage for fluid from the borehole to the annular space can be included.

Abstract: An improved stabilizing tool includes a body with a pocket, and a roller rotatably disposed in the pocket. The body includes a fluid passageway formed axially therethrough. The passageway has a first zone wherein the pressure of the fluid is relatively high and a second zone wherein the pressure is relatively low. A first conduit provides fluid communication between the first zone and an interior of the roller for the ingress of fluid to the interior, and a second conduit provides fluid communication between the interior of the roller and the second zone for the egress of the fluid back to the fluid passageway.

Abstract: A portable core sampler includes a portable electric drill having an output rotary shaft connected detachably to a coupler shaft that supports a water swivel which connects a source of water to an axial water delivery passageway in the coupler shaft. The passageway in the coupler shaft communicates with the water delivery passageway in an elongated core sampler tube connected detachably to the coupler shaft, either directly or through one or more spacer tubes, for simultaneous rotation with the coupler shaft. The end of the core sampler tube opposite the coupler shaft includes core cutting elements for cutting core material for collection in the core sampler tube. Water injected into the system assists the cutting elements in cleanly cutting sub-surface materials by removing heat and cuttings. An inner shoulder in the sampler tube supports a core sample in the core sample tube during retraction of the tube assembly from the sub-surface.

Abstract: A rotary cone drill bit (10) for forming a borehole includes a support arm-cutter assembly (26). A support arm (28) is integrally formed with the drill bit's body (22) with a spindle (30) machined integral thereto. The assembly (26) includes a cutter (12) with a cavity (34) for receiving the spindle (30). An inner seal gland (44) is formed between the spindle (30) and a wall (42) of the cavity (34). An elastomeric seal (46) is disposed in the inner seal gland (44) to form a first fluid barrier between. An outer seal gland (50) is formed between the spindle (30) and the cavity wall (42) and between the inner seal gland (44) and the borehole. A ring (56) is disposed in the outer seal gland (50) to rotate with the cutter (12). The ring (56) has a peripheral hole (58) therethrough. A gas conduit (60) is disposed within the support arm (28) for directing a flow of a gas, such as air, into the outer seal gland (50).

Abstract: This invention relates to a rotary drill bit having a body with leg members, where each of the leg members has a projecting conical cutter receiving journal. Each conical cutter has an axially extending recess open at one end and is rotatably mounted on the journal by friction reducing bearings interior to the conical cutters. The drill bit has a main cavity which extends down the center of the drill bit body. A jet nozzle provides an exit opening at the bottom of the main cavity. At least one passageway extends to and opens into the main cavity at one end and extends to and opens into the bearings at the other end. The end of the at least one passageway which extends to the main cavity is provided with a plurality of openings and a plurality of deflectors associated with the openings. When a gas-liquid mixture is passed through the main cavity, the deflectors will cause an abrupt change in the gas flow direction.

Abstract: A sealed rotary drill bit has a plurality of leg members, with each leg member having a projecting conical cutter receiving journal. A conical cutter has friction reducing bearings interior to the conical cutter for rotatably mounting the cutter on the respective journal. A sealing arrangement retains lubricant for the bearings. A circumferential porous gas restrictor is positioned concentric with and spaced outwardly from the sealing arrangement to form an annular gas chamber therebetween. Pressurized gas is carried by passageways into the annular gas chamber. The porous gas restrictor, which can be formed of metal particles bonded together, prevents drilling debris from getting past it, but the porosity of the restrictor allows pressurized gas to pass therethrough as a controlled dissipation and wash away drilling debris, thereby shielding the sealing arrangement from debris that might otherwise reach the sealing arrangement.

Abstract: An earth boring (rock) bit having a flexible diaphragm located inside the bearing shaft in a cavity between a threaded lug and a mating bearing sleeve. The diaphragm has an enlarged periphery, shaped somewhat like an o-ring, that is confined and sealed between opposed annular surfaces on the lug and the sleeve. The circular periphery of the diaphragm and cavity provide good compensation volume, from which excessive lubricant pressure is relieved by an enlarged portion which is punctured and contoured to discharge lubricant under excessive pressure while excluding drilling fluid. Simplicity and reliability are achieved by the elimination of multiple and complex manufacture and assembly operations.

Abstract: A rotating drill bit (10) includes a leg (12) and journal arm (14) on which is mounted a cone-shaped cutter (16). The cutter (14) rotates on the journal arm (14) by means of an anti-friction bearing including rollers (20) and ball bearings (26). Air is pumped through the journal arm (14) through conduits (30, 32 and 34). Air flows through the passages between rollers (20) and is collected in a cavity (52). The cavity (52) is vented to the borehole through a slot (54) in the trailing edge of the journal arm (14). A very narrow clearance in the order of a few thousandths of an inch is provided for rotational movement between the cone mouth shoulder (36) and last machined surface (40). Cone mouth shoulder (36) completely covers the last machined surface (40) around the entire periphery of the journal arm (14) except for the approximately 45.degree. slot (54) in the trailing edge of the journal arm (14).

Abstract: A drill bit for drilling into underground formations is disclosed, the drill bit having conduits for providing either lubricant or gaseous drilling fluid to the cutting cone bearings. In an alternate mode of operation, a mixture of lubricant and gaseous fluid is supplied to the bearings.

Abstract: A seal element for oil well tools, such as drilling cutters and roller reamers, which allows the drilling media to permeate into the bearing system of the cutter to cool and lubricate the internal mechanism. The seal element is adapted to control the particle size of contaminants flowing into the bearing system by filtering the drilling media. The bearings act as agitators during operation of the cutter to promote fluid motion through the bearing system. The seal and lubrication system may be utilized as a back-up to the conventional lubrication supply or as supplemental lubrication.

Abstract: A roller cutter drill bit detachably secured to a drill string for delivering drilling fluid under pressure to the bit, comprising a plurality of bearing journals at its lower end and passaging extending down in the bit body to each of the journals for flow of the drilling fluid from the drill string to the journals. The bit further comprises a plurality of roller cutters, each having a bore adapted to receive a respective journal, and bearings in the annular cavity between each roller cutter and the respective journal for rotatably mounting the roller cutter on the journal. The drilling fluid when supplied in sufficient quantity flowing through the passaging, past the bearing means and exiting the bit in the bore via the bearing cavity for cooling and cleaning the bearings, but when supplied in insufficient quantity boring cuttings being allowed to enter the bearing cavity and fouling the bearings.

Abstract: A drill bit comprising a bit body detachably secured to a drill string having a chamber therein to receive drilling fluid at a first pressure from the drill string, a nozzle for exit of the drilling fluid to the space between the bit body and the well bore at a second pressure lower than the first, and a depending leg; a roller cutter; a bearing assembly for rotatably mounting the roller cutter on the leg; a lubrication system in the bit body comprising a reservoir of lubricant, passaging for flow of lubricant from the reservoir to the bearing assembly, a seal member for blocking flow of lubricant out of the bit, an expansible chamber for pressurizing the lubricant to a third pressure greater than the second but less than the first, and a biased diaphragm for pressure compensation secured in a recess in the bit body in fluid communication at one side thereof with the lubricant and at the other side thereof with the drilling fluid in the space between the bit body and the well bore; and a sensor for sensing a

Abstract: A rotary drill bit having a body with a projecting journal and a conical cutter having an axially recessed open end for receiving the journal wherein only the upper portion of the open cone mouth in the cavity formed between the cone and the body is shielded from drilled debris intrusion and the circulating air is channeled in the bearing to the bottom portion of the open cone mouth for improved flow pattern through the various bearing segments whereby the incidence of plugging of the bit due to excess formation being forced into the bearing at the gaping open portion of the upper cone mouth is reduced.