Abstract: A soft excavator (10, 90, 110, 130) is disclosed which utilizes a jet of high velocity fluid flow such as air or water flow, preferably supersonic, through a nozzle (48, 92, 112) to excavate a material, such as the ground. A second passage for air flow is provided which is directed by an evacuator skirt (52, 102) in a direction along the excavator generally opposite the direction of discharge of the high velocity excavating flow to entrain the material excavated for disposal.

Abstract: A method and apparatus for removing mud from around and inside of a casing is shown and described. Examples of such casings include piles of offshore oil production platforms. In accordance with a preferred embodiment of the present invention, a submersible pump having a propeller and coupled to several nozzles is lowered to a position adjacent the mud to be removed. A volume of water is forced through the nozzles against the mud, the action of which, together with the propeller, serves to dilute and break up the mud. The submersible pump then forces the mud and water upward through a flexible tube to be discharged into open water.

Abstract: The installation for cleaning the zone near the drill hole contains a hollow body (1) in which is arranged a subassembly for generating hydrodynamic waves that is designed in the form of a turbulence chamber (3) that has, arranged tangentially in its upper part, entry channels (4) with which the subassembly is connected to the cavity of the body (1). The outlet channel (5) of the turbulence chamber (3) is designed with a conical taper.

Abstract: A method of erosive cutting of a hard material such as rock utilizes two spaced clusters of jets for high-pressure discharge of fluid in the course of their movement along the same longitudinal path over the hard material. One of the jet clusters has a fixed orientation for multiple-jet discharge at the hard material, while the other cluster of jets is subjected to oscillating excursions transverse to the direction of the path that both clusters are caused to follow. A cooling medium is directed at the working site between the two clusters. The result is a faster working rate and a more cleanly defined groove in the hard material, along the path of movement.

Abstract: A low-cost method drilling and completing wells attaches a non-rotating jet drilling tool to coiled tubing. After drilling, the tubing portion outside the well is cut and the remaining tubing becomes the liner or casing for the well. By also using a residual bend remover, centralizers, and injecting a thermal cement slurry, very low cost steam injector wells can be drilled and completed.

Abstract: A high-speed fluid/mechanical Jet erosion system utilizing a high-velocity, spinning jet stream discharged contiguous the surface to be cut. The spinning jet stream is developed from a tangentially driven vortex flow system adapted to merge and enhance the erosive high-speed fluid jet characteristics of fluid and abrasive particle impingement erosion with cavitational collapse erosion in both axial and tangential directions. The system further includes an apertured mechanical cutting element which places the exiting spinning jet immediately against the target formation, providing maximum mechanical and fluid energy transfer to the formation. In this manner, the system induces formation fracturing by assisting mechanically induced fracture propagation with the high-speed jet action while simultaneously exploiting high-speed jet erosion-induced kerfs with the mechanical action of the tool.

Abstract: Controllable drill head containing an elongated body of which one end is attached to a bore pipe and a spout element is mounted in a turnable manner on the other, foremost end of the body, in and opposite to an opening in this body, wherein the head contains an elongated, elastic, bendable element which at one end carries the spout element and which has been mounted in the body in such a manner that when being in a rest position the movable element stretches out in the longitudinal direction of the body, but which is elastically bendable in the cross direction of the body so as to alter the direction of the spout element through bending, a mechanism for (3) stopping the foremost end of the bendable element with the spout element in the forward direction without the element bending through and to keep the spout element from changing direction, and a mechanism for exerting forward pressure on a part of the bendable element which is situated further away from the foremost end of the body than the foremost end th

Abstract: Hydraulic drilling apparatus and method in which a drill head is driven toward the formation being drilled by the force of the drilling fluid, and the rate of advancement or penetration of the drill head is controlled by entrapping a fluid in a chamber to resist advancement of the drill head and allowing a controlled amount of the entrapped fluid to pass out of the chamber through an orifice to permit the drill head to advance at a controlled rate.

Abstract: A wellbore jetting tool has a novel packer assembly which enables the tool to be raised, lowered and rotated while operating, a nozzle which automatically raises to extend radially from the tool, and a flow system for returning slurry in an inner tube of cross section. The packer assembly is hydraulically actuated, and traps fluid to provide lubrication, which enables raising, lowering and rotation during operation while substantially maintaining the necessary sealing. The nozzle is raised by a torque generated by vanes disposed within the nozzle head reacting to fluid flow, and also by thrust from the cutting jet. The nozzle discharges this jet at an angle, thus biasing the nozzle appropriately. A breakaway feature allows abandonment of the nozzle if it jams when it is extended, ensuring that the pipestring may always be retrieved. The return of slurry through its own conduit reduces chances of a particle lodging in the slurry return line.

Abstract: A borehole mining process for recovery of petroleum from unconsolidated heavy oil formations. The process consists of drilling a borehole in the unconsolidated heavy oil reservoir, which is formed from sand particles aggregated by heavy oil, and positioning a casing and a first and second tubing string within the borehole. At least one nozzle is positioned on the lower end of the second tubing string and is oriented for fluid emission generally radially outwardly from the second tubing string. Fluid is then flowed downwardly through the second tubing string and outwardly through the nozzle, thereby eroding a cavity in the reservoir and forming a slurry consisting of the fluid, the heavy oil, and the particles from the reservoir. The slurry is flowed upwardly through the annulus between the first and second tubing strings to the upper end of the borehole for recovery of the heavy oil.

Abstract: Evaporite mineral solution mining process and apparatus comprising the steps of undercutting a bed or massive deposit by in-air jetting with an aqueous solution followed by solution mining of the mineral above the undercut with monitoring and control to cease the solution mining when the roof rock is adequately exposed to maintain a stable roof and stable pillar support. The resulting cavity exhibits steeply angled, nearly vertical sidewalls, flared upwardly and outwardly only 10.degree. to 15.degree. from the vertical plane normal to the edges of the undercut as compared to 45.degree. typical for morning glory cavities. A first plan vertical production well is drilled with a sump provided substantially adjacent to the floor rock. A second horizontal well is developed up dip to intersect and communicate with the production well. The air jet tool mechanism provides horizontal, slightly upwardly inclined jets (0.degree.-15.degree.

Abstract: A rotating head mounts a nozzle which creates cavitation in a pressurized fluid such that a surface may be quickly and efficiently cleaned. The rotation of the nozzle ensures a relatively wide cleaning path. The cavitation allows cleaning using only the pressurized fluid jet without any necessary abrasives, while still fully utilizing high rotational speeds. A preferred cavitating jet nozzle is also disclosed for producing cavitation in the pressurized fluid. The cavitating jet nozzle includes a pin received at a central position which lowers the pressure of the pressurized fluid such that cavitation bubbles form in the fluid. The pin is self-centering within the nozzle since it is free floating relative to a securing member which retains the pin in the nozzle. In addition, the pin preferably has an end face upstream of an outlet portion of the nozzle.

Abstract: A high-speed fluid/mechanical jet erosion system utilizing a high-velocity, spinning jet stream discharged contiguous the surface to be cut. The spinning jet stream is developed from a tangentially driven vortex flow system adapted to merge and enhance the erosive high-speed fluid jet characteristics of fluid and abrasive particle impingement erosion with cavitational collapse erosion in both axial and tangential directions. The system further includes an apertured mechanical cutting element which places the exiting spinning jet immediately against the target formation, providing maximum mechanical and fluid energy transfer to the formation. In this manner, the system induces formation fracturing by assisting mechanically induced fracture propagation with the high-speed jet action while simultaneously exploiting high-speed jet erosion-induced kerfs with the mechanical action of the tool.

Abstract: An extendable, retractable, erectable arm assembly for housing and supporting a water conduit extending outward from a tool located in a borehole, to a nozzle to produce a high pressure water cutting jet is provided. The arm assembly includes a plurality of interlocking arm segments for housing, supporting and moving the conduit through an angle of about 90.degree. from a stowed position to an operating position. The arm segments include integral, separable hinges capable of being interlocked such that pivotable movement is possible along any side thereof. These segments have mating apertures therethrough to accommodate the conduit. The assembly also includes an erecting device which provides compression on the segments and which gives the arm rigidity during movements. An alignment device is also included which keeps the segments aligned when the arm is deflected.

Abstract: This invention relates to flow pulsing methods and apparatus for various applications including downhole drilling equipment and in particular to an improved flow pulsing method and apparatus of this type to be connected in a drill string above a drill bit with a view to securing improvements in the drilling process.

Abstract: An extended reach penetrating tool which includes a tubing string lowered into a casing, anchored in position and including a cutting tool for forming a lateral hole in the casing. A formation penetrating tool is then substituted for the cutting tool on the tubing string and extended laterally through the hole in the casing and outwardly into the formation to a desired extent for enhancing production from the formation. The cutting tool for cutting a hole in the casing includes a laterally extendable cutting element urged radially from the tubing string by a piston and cylinder assembly with the cutting element in the preferred form being a rotatably driven cutting element which is extended radially from the tubing string into cutting engagement with the interior of the casing for forming a lateral opening.

Abstract: A wellbore jetting tool has a novel packer assembly which enables the tool to be raised, lowered and rotated while operating, a nozzle which automatically raises to extend radially from the tool, and a flow system for returning slurry in an inner tube of cross section. The packer assembly is hydraulically actuated, and traps fluid to provide lubrication, which enables raising, lowering and rotation during operation while substantially maintaining the necessary sealing. The nozzle is raised by a torque generated by vanes disposed within the nozzle head reacting to fluid flow, and also by thrust from the cutting jet. The nozzle discharges this jet at an angle, thus biasing the nozzle appropriately. A breakaway feature allows abandonment of the nozzle if it jams when it is extended, ensuring that the pipestring may always be retrieved. The return of slurry through its own conduit reduces chances of a particle lodging in the slurry return line.

Abstract: A method of working metalliferous deposits which includes tapping a pay zone by development boreholes, hydraulically mining for a mineral in the pay zone through the formation of brine having a level which is maintained below the location of hydraulic mining of the mineral, shaping a working chamber by shifting the location of hydraulic mining along the axis of the borehole within the confines of the pay zone and lifting the brine out of the working chamber to the surface. The hydraulic mining of the mineral is alternated with the lift-of brine to the surface, such that the location of hydraulic mining is shifted from the floor of the pay zone to the roof of the pay zone at a speed which is not less than the speed at which the level of brine is rising in the working chamber. The method also includes tapping a pair of boreholes and forming working chambers in each.

Abstract: A high pressure pipe consisting of a flexible high pressure hose which is attached at both ends to a tube. The tube is stiffer than the high pressure hose in order to allow the high pressure hose to be pushed into the ground without bending or buckling and thereby forming a hole in the ground.

Abstract: A manifold for a borehole miner, wherein the manifold is rigidly secured to a first and a second pipe of a pipe bundle; movably connected to at least one other pipe; and provided with a collimating nozzle unit associated with a deflector plate unit, such that a pressurized abrasive jet spray can be directed against the walls of a bore hole, and the back splash from the jet spray will be prevented from adversely affecting the pipes in the pipe bundle by the deflector plate unit.

Abstract: A method and apparatus for creating an underground bore hole employing a steerable boring head at the end of a remotely driven drill string. The boring head, preformed at an angle to the longitudinal axis of the trailing pipe string to bore along a curvilinear path is straightened by increasing the pressure of the fluid within the drill string above a predetermined range to enable drilling along a linear path. Subsequent reduction of the fluid pressure to normal drilling pressure returns the boring head to its former state along a resumption of a curvilinear drill path.

Abstract: A cavitating jet nozzle is disclosed for producing cavitation in a pressurized fluid such as a water used to clean a surface. The cavitating jet nozzle includes a pin received at a central position which lowers the pressure of the pressurized fluid such that cavitation bubbles form in the fluid. The pin is free-floating relative to a securing member which retains the pin in the nozzle, and is thus self-centering. The inventive cavitating nozzle is easily maintained since the pin is self-centering and need not be repeatedly centered. The pin preferably has an end face upstream of an outlet portion of the nozzle.

Abstract: A device for forming an elongated hole in the ground, comprising a hollow, flexible conduit, a head (2') which is connected to one end of the conduit and which is fitted with at least one nozzle (5') through which fluid passing along the conduit under pressure is delivered in such a direction and under such pressure that when the head is not in rotation, the head will form a hole of curved configuration and such that when the head rotates about its longitudinal axis and the conduit is moved forwards in the hole-forming direction the head will form a substantially straight hole, the end of the head facing towards the hole-forming direction being provided with a surface which is positioned obliquely to the longitudinal axis of the head and which assists the head in forming a curved hole.

Abstract: An excavation apparatus includes a suction system with a suction tank pneumatically connected to a blower through a filter subassembly. A suction hose is pneumatically connected to the suction tank. A liquid jet system includes a liquid reservoir fluidically connected to a liquid pump, which in turn is fluidically connected to a spray wand. The suction and liquid jet systems are mounted on a vehicle. An excavation method includes the steps of dislodging earthen material with a liquid jet from the spray wand and sucking it into the suction tank with the suction system.

Abstract: This invention relates to flow pulsing methods and apparatus for various applications including downhole drilling equipment and in particular to an improved flow pulsing method and apparatus of this type to be connected in a drill string above a drill bit with a view to securing improvements in the drilling process.

Abstract: Boring apparatus for forming a generally horizontal underground passage for a utility conduit or the like that includes a tool head with elongated body structure and a cutting face of ellipto-conical form at one end of the elongated body structure. The cutting face has a major axis and a minor axis and cutting bit structure is fixed to and projects forwardly from the cutting face and extends substantially the full width of the cutting face generally along the major axis. The tool head also includes coupling structure for attaching the tool head to a drill string such that the cutting tool face is offset from the drill string axis. Structure in the cutting face defines a cutting fluid orifice adjacent the cutting bit structure for directing a high velocity jet of cutting fluid forwardly of the cutting tool face.

Abstract: Hydraulic drilling method and apparatus in which the drilling fluid itself is utilized to control the direction in which a hole is bored in the earth. The drilling fluid is discharged through a plurality of forwardly facing nozzles which are inclined at different angles about the axis of the drill head, and the drilling fluid is selectively applied to the nozzles by a rotatable valve member to control the direction in which the hole is cut.

Abstract: A method and apparatus for creating an underground bore hole using high pressure fluid within a drill string to disturb and displace the subsoil. The drill string is steerable by increasing the pressure of the fluid above a predetermined range to a second range and apparatus is responsive thereto to effect a bending movement and change in the direction of the drill string.

Abstract: An abrasive swivel assembly for providing a rotating, particle-laden fluid stream and, ultimately, a rotating particle-laden fluid jet is disclosed herein. This assembly includes a tubular arrangement for providing a particle-free stream of fluid, a swivel assembly for rotating a section of the tubular arrangement, and a tubular end section for introducing solid particles into the particle-free fluid stream at a point along the rotating tubular section, whereby to produce a particle-laden fluid stream. This last-mentioned stream can then be used in combination with a cooperating nozzle arrangement for providing a rotating particle-laden fluid jet. In an actual working embodiment, the fluid stream is of sufficiently high pressure so that the abrasive jet can be used as a cutting jet.

Abstract: Hydraulic drilling method and apparatus in which the drilling fluid itself is utilized to control the direction in which a hole is bored in the earth. The orientation of the drill head is monitored by tilt and roll sensors, and the discharge of drilling fluid through radially or obliquely directed nozzles is controlled by poppet valves in accordance with the orientation to control the direction in which the hole is cut.

Abstract: The head is carried by two flexible continuous drill pipes which surround each other and which are flexible enought to be uncoiled from a reel but which are still rigid enough almost not to get twisted in the ground on themselves or relative to each other during the operation of the head. The head is directed in the ground by means of fluid wich is pumped through one of the pipes and wherewith the head is repelled relative to the wall of the already formed portion of the hole. One of the pipes connects to one or more directable spray nozzles on the front end of the head, the other one connects to one or more sidewise-issueing openings wherein preferably a directable spray nozzle is mounted.

Abstract: A process for repairing underground sewer lines by preventing the infiltration of groundwater into a leaking sewer line comprising determining the location of the leakage into the sewer line, vacuum excavating a bore into the ground to the sewer line in the vicinity of the leak, depositing a quantity of a water swellable material such as an argillaceous material selected from the group consisting of bentonite and attapulgite into the bore to a depth of at least about one foot above the sewer line, tamping the argillaceous material in the bore, depositing a quantity of gravel over the argillaceous material in the bore, and backfilling the excavation. The water-swellable material also contains a dye which will infiltrate into the sewer line until the leak is sealed. Through a downstream inspection, the presence or absence of the dye indicates whether water infiltration into the sewer line has stopped.

Abstract: Apparatus for pressurized cleaning of well flow conductors. The apparatus has a non-rotating inner mandrel, an adapter to connect the inner mandrel to a work string, a rotating housing on the exterior of the inner mandrel, and a nozzle body attached to the housing. An alternative embodiment of the invention allows cleaning tools to be attached to a modified nozzle body and rotated therewith. Fluid pressure flowing through the inner mandrel will cause the housing to rotate relative to the inner mandrel. Rotation is used to direct fluid jets in the nozzle body towards different portions of the interior of the flow conductor. Rotation of a cleaning tool can also be used for combined mechanical and hydraulic drilling to remove deposits from within a well flow conductor.

Abstract: A hydraulic borehole mining system has a cutting jet nozzle supported on an insert short length of tubing of a cutting jet head within a water supply conduit in the lowest section of a multi-conduit pipe string that extends from the surface through a borehole to a target zone to be mined. A rod extending from the surface through the string outside of the water supply conduit connects to the head to reposition the nozzle vertically, independent of movement of the conduit or string. The borehole annulus is sealed and connected to a surface standpipe for development of a hydrostatic head pressure that acts, with or without downhole pump assistance, to raise the slurry created by the nozzle jet up through a second conduit in the pipe string. Material is pumped down the same second conduit after mining to backfill the hole.

Abstract: A fluid-operated self-propelled subsoil penetrating tool of the type including an elongated housing member having a penetrating nose portion capable of ejecting a jet of liquid under high pressure to break up and disrupt the subsoil adjacent such nose portion followed by a two-component hammering of such soil to displace and compact same as the tool advances. Remotely-operated steering mechanisms control the path of the tool while remotely-read instruments denote the position, depth, direction and attitude of the tool. A trailing umbilical cord provides all motive and operational fluids and electrical power while transmitting instructions and data between the tool and the remote control station. A unique internal structure reduces the rotation of the tool as it advances and provides for the reverse movement of the tool and electrical supplies through the bore created by the movement of the tool through the subsoil.

Abstract: A technique for providing a continuous underground tunnel between first and second spaced-apart points and for installing new cable, pipe or conduit is disclosed herein. This technique utilizes a boring device including means for boring through soil and a thrust conduit which pushes the boring device through the soil from a first starting point to a second end point as the device bores through the soil, whereby to form a tunnel between the two points. Thereafter, the cable to be installed within the tunnel is attached to the front end of the boring device and the latter is pulled back through the tunnel to its starting point by means of the thrust cable, thereby automatically pulling the new cable in place.

Abstract: An excavating system, such as for drilling an oil or gas well, includes a source of high pressure fluid and a drillstring through which the fluid is conducted to an excavating apparatus connected to the bottom of the drillstring. The excavating apparatus includes a drill bit having mechanical cutting elements for mechanically boring into an earthen formation. The excavating apparatus also includes a nozzle rotatably mounted to the body of the drill bit so that the nozzle is rotatable about an axis of rotation different from the axis of rotation of the drill bit. As the drill bit is rotated about its axis of rotation, high pressure fluid is ejected from the nozzle to rotate the nozzle about its axis of rotation while the nozzle orbits the axis of rotation of the drill bit.

Abstract: A technique for providing a continuous underground tunnel between first and second spaced-apart points and for installing new cable, pipe or conduit is disclosed herein. This technique utilizes a boring device including means for boring through soil and a thrust conduit which pushes the boring device through the soil from a first starting point to a second end point as the device bores through the soil, whereby to form a tunnel between the two points. Thereafter, the cable to be installed within the tunnel is attached to the front end of the boring device and the latter is pulled back through the tunnel to its starting point by means of the thrust cable, thereby automatically pulling the new cable in place.

Abstract: An abrasive swivel assembly for providing a rotating, particle-laden fluid stream and, ultimately, a rotating particle-laden fluid jet is disclosed herein. This assembly includes a tubular arrangement for providing a particle-free stream of fluid, means for rotating a section of the tubular arrangement, and means for introducing solid particles into the particle-free fluid stream at a point along the rotating tubular section, whereby to produce a particle-laden fluid stream. This last-mentioned stream can then be used in combination with a cooperating nozzle arrangement for providing a rotating particle-laden fluid jet. In an actual working embodiment, the fluid stream is of sufficiently high pressure so that the abrasive jet can be used as a cutting jet.

Abstract: Hydraulic drilling apparatus and method suitable for use in a variety of applications including the drilling of deep holes for oil and gas wells and the drilling of vertical, horizontal or slanted holes, drilling through both consolidated and unconsolidated formations, and cutting and removing core samples. The drill head produces a whirling mass of pressurized cutting fluid, and this whirling fluid is applied to a discharge nozzle to produce a high velocity cutting jet. In one embodiment, the fluid is discharged from a central nozzle as a thin wall conical cutting jet, and a plurality of axially directed jets are spaced about the central nozzle for removing material within the circular groove cut by the conical jet. The conical jet can be used without the axially directed jets to cut core samples. In a second embodiment, the discharge nozzle comprises an oblique bore in a rotor which is driven at a relatively slow speed (e.g. 5-50 rpm) by the whirling fluid in the drill head.

Abstract: The head is carried by two flexible continuous drill pipes which surround each other and which are flexible enough to be uncoiled from a reel but which are still rigid enough almost not to get twisted in the ground on themselves or relative to each other during the operation of the head. The head is directed in the ground by means of fluid which is pumped through one of the pipes and wherewith the head is repelled relative to the wall of the already formed portion of the hole. One of the pipes connects to one or more directable spray nozzles on the front end of the head, the other one connects to one or more sidewise-issueing openings wherein preferably a directable spray nozzle is mounted.

Abstract: The invention provides apparatus for making a tunnel. A flexible tube connects to a head consisting of a body and a nose mounted for movement thereon. The nose has an abutment face adjustable in position relative to said body, and carries a nozzle. The nose may be a bevelled cylinder which may be rotatable relatively to the body by a steering mechanism or be conical and be tiltable by jacks operable from above the ground.

Abstract: A technique for providing a continuous underground tunnel between first and second spaced-apart points and for installing new cable, pipe or conduit is disclosed herein. This technique utilizes a boring device including means for boring through soil and a thrust conduit which pushes the boring device through the soil from a first starting point to a second end point as the device bores through the soil, whereby to form a tunnel between the two points. Thereafter, the cable to be installed within the tunnel is attached to the front end of the boring device and the latter is pulled back through the tunnel to its starting point by means of the thrust cable, thereby automatically pulling the new cable in place.

Abstract: Hydraulic drilling apparatus and method suitable for use in a variety of applications including the drilling of deep holes for oil and gas wells and the drilling of vertical, horizontal or slanted holes, drilling through both consolidated and unconsolidated formations, and cutting and removing core samples. The drill head produces a whirling mass of pressurized cutting fluid, and this whirling fluid is applied to a discharge nozzle to produce a high velocity cutting jet. The cutting action is enhanced by abrasive material in the drilling fluid. The direction of the borehole is controlled by controlling the discharge of the drilling fluid either in side jets directed radially from the distal end portion of the drill string which carries the drill head or in a plurality of forwardly directed cutting jets.

Abstract: A well casing penetrator includes an elongated housing enclosing an outwardly movable hydraulic cylinder driven punch for cutting an opening in a casing. A high pressure liquid jet nozzle is mounted on the end of a hose which moves outwardly through an axial bore in the punch when extended through the casing to cut a radially extending opening in the surrounding earth. The punch includes arcuately curved longitudinal slots along opposite sides which cause tabs to be bent back along opposite sides of the opening cut in the casing to prevent dislodging of any portion of the casing from the casing as a consequence of the operation of the punch. A spool piston is connected to a single accumulator that is pressurized to urge the spool piston toward a first position in which work fluid controlled by the spool piston retracts the hydraulic punch cylinder and a hose drive cylinder for moving the hose in the punch.

Abstract: A method and apparatus for installing underground utilities using an offset head fluid jet drilling and reaming apparatus. The drill is maneuverable and provides means for remote sensing of orientation and depth. Embodiments are illustrated with single and multiple jet cutting orifices.

Abstract: Hydraulic drilling apparatus and method suitable for use in a variety of applications including the drilling of deep holes for oil and gas wells and the drilling of vertical, horizontal or slanted holes, drilling through both consolidated and unconsolidated formations, and cutting and removing core samples. The drill head produces a whirling mass of pressurized cutting fluid, and this whirling fluid is applied to a discharge nozzle to produce a high velocity cutting jet. The cutting action is enhanced by abrasive material in the drilling fluid. The direction of the borehole is controlled by controlling the discharge of the drilling fluid either in side jets directed radially from the distal end portion of the drill string which carries the drill head or in a plurality of forwardly directed cutting jets.

Abstract: An apparatus and method for drilling a bore hole (B) along an underground arcuate path (P) between two surface locations (O,E). The bore hole (B) is drilled in one direction with a drill string (10) having a leading pipe section 12 with a drill bit (14) thereon. Drilling fluid is supplied to the drill bit (14) during the drilling operation. Upon completion of the initial bore hole (B), the hole (B) may be enlarged by a reamer (40). Then, a production conduit (38) is connected to the reamer (40) for being pulled by the drill string (10) through the enlarged bore hole (D). Cement is supplied through the drill string (10) for discharge at the reamer (40) into the bore hole (D) adjacent the leading end of the production conduit (38) and fills the annulus A between the conduit (38) and the inner peripheral surface of the enlarged bore hole (D). In one embodiment (FIG. 12), the drill string (10B) is encased in cement in the initial bore hole (B) and forms a casing for receiving a small diameter production cable.

Abstract: A process and apparatus for generating high velocity particulate containing fluid jets is provided which is capable of cutting hard materials such as rock and concrete, and is especially useful for notching blast holes to control the pattern of explosion and material removal. A particulate passage valve is provided to open and close the particulate passage in response to changes in fluid pressure. The apparatus may be portable, durable and lightweight. The nozzle assembly may be inserted directly into the drill hole and is operable in any orientation to issue one or a plurality of particulate containing fluid jet streams.

Abstract: An apparatus and method for drilling a pilot bore hole (B) along an underground arcuate path (P) between two surface locations (O, E). The pilot bore hole (B) is drilled in one direction with a drill string (10) having a leading pipe section (10A) of a reduced diameter to provide increased flexibility. Upon completion of the pilot bore hole (B), a reamer (48) connected to a product conduit (46) is connected to the drill string (10). Drill string (10) pulls the reamer (48) and product conduit (46) along the pilot bore hole (B) in an opposite direction for enlarging the bore hole (B) to receive the product conduit (46). A spud bit (34) has a flat or blunt leading end portion (34A) with a discharge opening (34D) therein to discharge high velocity drilling fluid into the formation at a location offset from the longitudinal axis of the drill string (10) to assist in guiding the drill string (10). An in-hole hydraulic motor (70) is provided in an embodiment (FIG.