Abstract: An earth boring bit of the "air cooled" type that includes an air passage access system, including a generally vertical passage with an opening on the exterior of the leg or in the shank cavity that forms part of the body of the bit. This vertical passage is accessible through the opening by removal of a core that expands or retracts by altering the pressure exerted against it by two plates and a threaded fastener.

Abstract: The enhanced flow drill bit includes an upper body section having a bore therein and a lower body section formed integrally with the upper body section and including three passageways to transmit fluid outwardly of the drill bit body. The passageways, when intermittently open, transmit fluid flowing downwardly through the drill bit body and outwardly of the passageways to cause a cross flow in the area of the cone-type cutters. A rotor is mounted within a bore within the upper body section to intermittently open and close passageways to provide for an intensification of flow through the remaining open passageway to create high jet impact force of fluid flowing outwardly of the drill bit body to enhance cross flow and the removal of drill cuttings.

Abstract: A drilling bit, such as a crenellated drilling bit for fluid-jet supported rotary drilling in rock comprises a nozzle for directing a jet of high-pressure fluid against rock material being bored. In addition to transporting away rock chips, the jet penetrates fissures in the rock and supports the breaking down of the rock structure by the drilling bit. Since such nozzles tend to wear more rapidly than the cutting edges of the drilling bit, a readily exchangeable nozzle insert is provided. The nozzle insert is seated in a retaining body incorporated in the drilling bit and is held in the retaining body by a threaded annular cap. The annular cap has a hexagonal recess for accommodating a tool such as an Allan-key.

Abstract: A rotary cutter assembly comprises a drill head having a plurality of receptacles which releasably receive rolling cutter bit assemblies. The bit assemblies are locked in position by a locking sleeve connecting transverse fluid passageways of the drill head and bit assembly. Radially locking means in the form of pins received in complementary slots parallel to the rotational axis of the rotary cutter assembly are also provided.

Abstract: A rotary drill bit (10) having a plurality of diamond cutting elements (48) each having a cutting face (60) with a discharge nozzle (64) therein. The discharge nozzle (64) directs the flow of drilling fluid away from the cutting face (60) and is surrounded by the cutting face (60).

Abstract: A low pressure differential compensator for use in a lubrication system having a lubricant reservoir is provided, the reservoir providing lubricant to a bearing area between relatively rotatable elements having a seal therebetween. In particular, the low pressure differential compensator includes a flexible elongated diaphragm having a plurality of longitudinally-extending ribs which expand radially with respect to the longitudinal axis of the reservoir in response to the pressure differential across the seal. The radially collapsing and expanding flexible diaphragm is free operating and has no inherent restrictions which require increased pressure to overcome. Therefore, the pressure differential across the seal is minimized, increasing the effective life of the seal.

Abstract: A drilling device comprises a drilling head including a rotating body through which runs a duct for supplying, under pressure, air, or mud, or water or other drilling fluid. At least one rotating cutting element is mounted on a shaft fixed on the rotating body so that the axes of rotation of the rotating body and of the cutting element diverge in the drilling direction. The cutting element is a disc having a ring-shaped cutting part. The rotating body bears on the opposite side to that bearing the rotating shaft of the disc a counter-reacting element placed in such a way that the element rests against the drilling wall to center the drilling head by compensating for the radial component of the reaction of the ground on the disc and to strengthen the wall. The point of contact of the element and wall which is highest up on the device is no higher than the highest point of the ring-shaped cutting part.

Abstract: A boring tool which comprises a hollow boring tool body constructed by fitting a hollow boring head provided with cutting tips to the end of a hollow boring bar, and wherein an inner leftward twisted screw is formed on the inner peripheral wall of the hollow boring bar; and an outer rightward twisted screw is formed on the outer peripheral wall of the hollow boring bar; when the boring tool body is clockwise rotated, the cutting fluid is carried forward to the end of the boring tool by the inner leftward twisted screw, and the cutting fluid which has cooled and lubricated the cutting tips and chips entrained with said cutting fluid are forcefully discharged by the outer rightward twisted screw.

Abstract: An earth boring rock bit having a sealed bearing 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 seal and cleaning debris from the area of the seal. An air groove scraper is mounted on the shaft in the exit port of the annular groove to prevent the annular groove from becoming plugged by debris mixing with moisture in the hole.

Abstract: This invention relates to roller cone, air circulation type rock bits. Means are provided on the rock bit body as well as on the shirttail portion of each of the legs extending from the body to provide a relief to pass rock chips from the borehole bottom and up the drill string as the air circulation roller cone bit works in a formation.

Abstract: Apparatus and methods are disclosed for drilling a well. A separator sub includes a cyclone separator which separates a stream of drilling mud into a less dense first portion and more dense second portion. The stream of drilling mud flows downward in an annular stream around the cyclone separator and then flows into a lower end of the cyclone separator. The less dense first portion of the stream of drilling mud is directed from the cyclone separator downward to a drill bit so that the drilling mud adjacent the drill bit has a density less than an initial density of the stream of drilling mud. The more dense second portion of the stream of drilling mud is directed upward from the cyclone separator and is ejected into a well annulus with an upward component of velocity and thereby reduces a hydrostatic drilling mud pressure adjacent the drill bit.

Abstract: Apparatus and methods are disclosed for drilling a well. A separator sub is used to separate a stream of drilling mud into a less dense first portion and more dense second portion. The less dense first portion of the stream of drilling mud is directed downward to a drill bit so that the drilling mud adjacent the drill bit has a density less than an initial density of the stream of drilling mud. The more dense second portion of the stream of drilling mud is ejected into a well annulus with an upward component of velocity and thereby reduces a hydrostatic drilling mud pressure adjacent the drill bit.

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: 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: 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: Disclosed is a drill bit with an eduction jet which discharges drilling mud upwardly through nozzles having wedge shaped apertures oriented such that the wedge shape is tangential to the central axis about which the drill bit rotates. Expelled mud projects a wedge shaped dynamic stream of mud which retains the definition as an eductive column which rotates with the drill bit and therefore has relative motion revolving transverse to the hydrostatic column bearing upon the bit. Throughout the regions in which it retains definition, the eductive column creates a low pressure zone immediately behind it and the low pressure zone enhances the ability of flushing jets to remove cuttings from the bottom of the borehole by drawing the cuttings above the drill bit. The manufacture of drill bits with wedge shaped eduction jets is also disclosed, including the manufacture by modification of conventional tri-cone bits.

Abstract: A rotary bore hole enlarging bit is connected to a rotary pipe string having a drilling fluid flow path and an actuator flow path. The bit comprises a body structure including inner and outer telescopic body sections, expansible and retractible arms carrying cutters on the outer body section and an expander on the inner body section engageable with the arms to expand the arms and cutters upon telescopic movement of body sections in one relative direction. A piston and cylinder is provided between the inner and outer body sections to secure relative telescopic movement between the body sections. A first passage is disposed in the body structure and expansible arms and cutters for conducting drilling fluid to the cutters from the drilling fluid flow path, there being a second passage in the body structure for conducting actuator fluid to the piston and cylinder from the actuator fluid flow path.

Abstract: A jet rotary drill bit confirming a first strainer element allowing the passage of mud carrying small-sized particles, but preventing relatively coarse particles from passing to the jet nozzles. The first strainer element is self-cleaning and the relatively coarse particles are passed on to a second strainer on which they remain trapped.

Abstract: A rotary roller bit comprising at least one rotatably carried roller cutter (12) and provided with sealing means (21) for preventing impurities from entering into the bearing system (14, 15, 16,) of the roller cutter. For purposes of preventing axial and wobbling movements of the roller cutter (12) relative to the bit head from creating high contact pressure at the contact surface between the sealing means (21) and the surface against which same seals the sealing means (21) is provided with an elastically yieldable tongue (25) which extends radially relative to the rotational axis of the roller cutter (12).

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 hybrid rock bit is disclosed which consists of a pair of cone cutters mounted to legs 120.degree. apart with an extended drag bit leg occupying the remaining 120.degree. segment. Several synthetic diamond stand-off type studs are strategically located and inserted in insert holes formed in the face of the drag bit leg. Nozzles are placed in front of the cutting face of the diamond studs to cool and clean the studs as the bit works in a borehole.

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 stabilizer for a tool, such as a rotary drill bit, comprises at least two blades spaced radially about the axis of the tool. Two adjacent blades define a venturi-shaped free angular space for a flow of drilling fluid. The width of each of the blades increases over at least a first portion, measured from the lower end of the blade, of the height of each blade. The height of the first portion is at least equal to one half of the width of the lower end of the free angular space.

Abstract: A drill bit having three cone-shaped cutters is formed with two drilling fluid nozzles on opposite sides of one of the cutters and with an enlarged return passage for the drilling fluid being formed between the other two cutters. Flow restrictors adjacent the two nozzles restrict the flow of return fluid in those areas. A flow diverter in the dome area of the bit extends into the space between the cutters to better direct fluid across the bottom of the hole where cuttings are being generated by the cutter teeth.

Abstract: A check valve for a rock drill comprises a valve plate carrying a cylindrical strainer. An insert is carried by the valve plate and is movable between valve-open and valve-closed positions. A spring biases the insert to a valve-closed position. The insert unit includes a lid which engages and covers the top of the strainer in a valve-open position, and a bottom plate which covers the valve plate in a valve-closed position to prevent cuttings from fouling the valve mechanism.

Abstract: A rotary roller bit for drilling earth and rock formations, having a main body and three legs extending outwardly therefrom. Each of the legs carries a conical roller cutter with internal bearings and there is a seal around the periphery of the top of the roller cutter. The periphery of the roller cutter is spaced from the adjacent portion of the leg so as to provide a jet slot for the discharge of air. Adjacent the slot and radially inwardly is an air chamber which is formed between an annular surface of the leg and a seal ring. The air chamber is substantially greater in its dimension axially of the roller cutter and air is supplied to it under sufficient pressure to cause a jet of air to flow from the jet slot at a sufficient rate to prevent the entry of rock particles and dirt into the roller cutter.

Abstract: A system for continuous lubrication of bearings in a drilling apparatus including a roller bit having at least one pivot and a cutting roller rotatably supported on the pivot by bearings. The system comprises pumping means in the form of spiral or oblique grooves on one of the spaced confronting faces of the roller bit and cutting roller and a flow opening or port arranged to effect flow of a flushing liquid through the bearing upon rotations of the cutting roller. The grooves may be selectively oriented to pump flushing liquid through the annular gap between the roller bit and cutting roller faces radially inwardly or radially outwardly for a given direction of rotation of the cutting roller.

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 jetting apparatus is provided to be a part of a drill string used in drilling a well. The apparatus functions to reduce the hydrostatic pressure of the drilling mud on the bottom of the hole to approach or attain optimal drilling conditions. The apparatus has a body with a plurality of upwardly facing shoulders. A jet nozzle is placed in each of the shoulders to direct or discharge mud vertically upwardly along and parallel to the lower part of the drill string to provide a jet lifting action which reduces the hydrostatic mud pressure on the bottom of the bore hole.

Abstract: A hole reamer according to the invention includes a main body or support with roller cutters rigidly connected to a drill stem, and an additional support with roller cutters arranged co-axially with the main body or support. A additional support device can move along the axis of the main body and is provided with a means to effect this longitudinal movement. The main body and additional support device are adapted to drill holes of one diameter with consequent reaming thereof.

Abstract: A rotary drill bit with downwardly extended circulation nozzle means an outwardly facing portion of which serves as a bit stabilizer wherein the upper portion of the nozzle means is on a greater diameter than the lower portion thereof so that the lower portion is inset from the wall of the formation, the upper portion of the nozzle means being machined from a given larger diameter to a diameter approximately but preferably slightly less than that of the bit body, and providing in the machine surface hardened inserts such as tungsten carbide.

Abstract: An underreaming tool with cutter arm position indication. An elongated body portion has a coupling for coupling one end thereof to a lower end of a lower drill string. A pair of arms are pivotally mounted on the body portion. Means is provided for relatively positioning the cutter arms apart in a cutting position and closer together in a non-cutting position and having an overridable condition wherein either of the cutter arms may be either in a cutting or a non-cutting position. A fluid passage is provided in the body portion comprising an input port at one end of the body portion and first and second output ports. One output port is adjacent to each of the cutter arms.

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: Drill cuttings are effectively removed from the bottom of a bore before they can adversely affect the operation of the bit. The bit includes a body member rotatably supporting individual cutter members. A shield means projects from the body member proximate the cutter members. A first portion of the shield means has an outside diameter substantially equal to the outside diameter of the cutter means and substantially equal to the diameter of the bore and a second portion having an outside diameter substantially less than the outside diameter of the cutter members and substantially less than the diameter of the bore. A first passage extending through the bit is adapted to provide communication with a vacuum source to assist in removing the drill cuttings. A second passage extending through the bit is adapted to provide communication with a gas pressure source to assist in removing the drill cuttings.