Abstract: A drilling assembly supports a liner for making a wellbore. The BHA comprises a pilot bit and a reamer above it that is larger in diameter than the suspended liner. If the BHA needs to be pulled out, the reamer is brought into contact with the liner and a latch mechanism between the two engages as another latch that had held the reamer bit to the BHA is released. The reamer bit stays with the liner as the BHA is pulled and later reinserted. On the way in the BHA latches to the reamer bit which then unlatches from the liner bottom. Preferably, splines and a shoulder on the BHA are used to drive the reamer bit as opposed to any power being transmitted through the latch between the BHA and the reamer bit. However, the latch mechanism between the BHA and the reamer bit could also provide torque and weight on bit for drilling operations. The process may be repeated.

Abstract: An apparatus that facilitates the insertion of a stanchion into the ground. The apparatus comprises a first side including a plurality of connection apertures, a second side including a plurality of connection apertures, and at least one connector engaging the connection apertures to removably engage the first side to the second side. The first and second sides reposition the ground and substantially separate the stanchion from the ground during insertion. Additionally, the apparatus maintains the integrity of the hole into which the stanchion is placed during insertion of the stanchion into the ground. Preferably, the first and second sides define a substantially circular opening when engaged to one another. Additionally, each side includes a length and the connector substantially spans the length and vertically connects the first side to the second side along the length.

Abstract: A method of drilling a borehole into a subsurface earth formation, using a tubular drill string which includes at its lower end a bottom hole assembly comprising a drill bit, a drill steering system, and a surveying system. The drill string includes a selectively closable passageway for passing an auxiliary tool from a first position interior of the drill string above the bottom hole assembly to a second position. In the second position, at least part of the auxiliary tool is exterior of the drill string below the bottom hole assembly. The drill string is progressed into the earth formation by drilling. When a tool operating condition is met the passageway is opened and the auxiliary tool is passed through the passageway from the first position to the second position, where the auxiliary tool is operated.

Abstract: The present invention provides a global drilling system comprising a crown bit, a driver drill bit and a square drill bit. The crown bit has a tubular body with an inner surface and an outer surface, wherein the inner surface circumscribes a hollow passageway, and a pair of projections extending into said hollow passageway. The pair of projections are positioned substantially opposite one another on said inner surface. The driver drill bit has a drilling head with a pair of cut-away portions positioned substantially opposite one another and a pair of locking surfaces adapted for engaging the projections on the crown bit. The square drill bit has a drilling head with two tapered cut-away portions positioned substantially opposite one another. Each cut-away portion corresponds to one of the pair of projections such that the drilling head is able to pass through the hollow passageway of the crown bit.

Abstract: The invention relates to a method for drilling, being carried out by a drilling apparatus, having a drilling device (1) that comprises a casing part (2) and a drilling unit (3), in the drilling head (I) of which there are first drilling means (4) for drilling a center hole and second drilling means (5) for reaming of the center hole for the casing part (2) as well as flushing flow arrangement (6) for flushing of waste, being generated. At least during the drilling situation, the first drilling means (4) are coupled by a power transmitting and, in order to enable removal of the same from the hole, removable arrangement, such as a bayonet coupling or like, with the second drilling means (5).

Abstract: The steel drill string attached to a drilling bit during typical rotary drilling operations used to drill oil and gas wells is used for a second purpose as the casing that is cemented in place during typical oil and gas well completions. Methods of operation are described that provide for the efficient installation of a cemented steel cased well wherein the drill string and the drill bit are cemented into place during one single drilling pass down into the earth. Apparatus is described having a portion of a drilling assembly that is selectively removable from the wellbore without removing the casing. A one-way cement valve is installed near the drill bit of the drill string that allows the cement to set up efficiently under ambient hydrostatic conditions while the drill string and drill bit are cemented into place during one single drilling pass into the earth.

Abstract: Equipment and methods which may be used in conjunction with an underbalanced well completion. In a described embodiment, a valve for use in a subterranean well in conjunction with a tool conveyed through the valve in a container is provided. The valve includes a passage formed longitudinally through the valve, a closure assembly which selectively permits and prevents flow through the passage, and an engagement device which engages the container as the tool is conveyed through the passage. The closure assembly permits flow through the passage when the container is conveyed into the passage, and the closure assembly prevents flow through the passage when the container is removed from the passage. Engagement between the container and the engagement device separates the tool from the container.

Abstract: A method and apparatus for a drilling with casing includes therewith a drill shoe configured for later drilling through thereof in situ, with cutters retainable thereon in response to the forces encountered during borehole drilling, yet moveable from the envelope through which the later drill shoe will pass when cutting through the in situ drill shoe. The drill shoe includes one or more profiles thereon, into which blades carrying the formation drilling cutters are disposed. The profiles include at least one projection thereon, which is received within a mating slot in the blades. The blades also may be configured to have opposed sections which are configured with respect to one another to have an included angle of less than ninety degrees.

Abstract: The steel drill string attached to a drilling bit during typical rotary drilling operations used to drill oil and gas wells is used for a second purpose as the casing that is cemented in place during typical oil and gas well completions. Methods of operation are described that provide for the efficient installation of a cemented steel cased well wherein the drill string and the drill bit are cemented into place during one single drilling pass down into the earth. Apparatus is described having a portion of a drilling assembly that is selectively removable from the wellbore without removing the casing. A one-way cement valve is installed near the drill bit of the drill string that allows the cement to set up efficiently under ambient hydrostatic conditions while the drill string and drill bit are cemented into place during one single drilling pass into the earth.

Abstract: The invention describes a boring device for producing tubed bored piles, in which during sinking, simultaneously a tubing-with inside auger is introduced into the ground using the rotary boring method.

Abstract: A device for drilling holes, including a drill bit with a drilling or breaking surface, a drill rod for introducing a rotary or percussive force and for introducing a rinsing or cooling fluid into the drill bit and a sheath pipe which defines a hollow space between the drill rod and the inside of the sheath pipe and which is supported on the drill rod or which can be connected to the drill bit. In a drilling position, the sheath pipe is situated at a distance from the rear side of the drill bit facing away from the breaking surface and the drill bit can be introduced into a rinsing position for the hollow space between the sheath pipe and the drill rod with its rear side resting on the front end of the sheath pipe facing towards the drill bit or can be connected to the front end of the sheath pipe.

Abstract: A pressure and temperature core sampler comprises a tool for recovering cores specifically enabling the evaluation of methane hydrate resources. Because methane hydrate tends to decompose under conditions of pressure decrease and/or temperature increase as the samples are retrieved to the surface, a coring tool in accordance with the present invention provides a self-contained system for retrieving core samples at or near in situ pressure while cooling the core sample. The coring tool is preferably a wire line retrievable device that provides for nearly continuous coring during the drilling operation.

Abstract: A device for connecting a tool to a mechanical drive contains as the coupling element a spring washer coupling or clutch, which is made in one piece from metal and at least in the rotation direction has a limited resilience. Use is made thereof for preventing torque peaks in the case of a sudden deceleration of the tool, e.g. if a screw strikes a wood surface.

Abstract: A bit retainer for a percussion bit assembly has a bore and upper and lower lips extending into the bore. Multiple slots extend from the lower end of the retainer member to a terminal end disposed intermediate the upper and lower ends, forming multiple cantilever beam segments. The cantilever beam segments are resiliently, radially deflected by the retention shoulder of the percussion bit to mount and retain the bit.

Abstract: An apparatus for providing a mooring anchorage, and a method of drilling and installing a pile in ground comprising the steps of: providing a pile, providing a drill bit at an end of the pile rotatable relative to the pile, engaging the ground with the drill bit, and rotating the drill bit relative to the ground and the pile generating a hole into which the pile is received.

Abstract: A one trip method for drilling a wellbore below a cemented casing is disclosed. An apparatus for use in performing the method is also disclosed. The method comprises lowering a drill bit into a casing cemented in the wellbore. The casing has float equipment connected therein. The drill bit is rotated in the casing above the float equipment so that it expands radially outwardly to a diameter greater than the inner diameter of the casing. The float equipment, which can be a float shoe or a float collar or any other type of float equipment known in the art, includes an outer case with a valve connected therein. The outer case is comprised of a drillable material. Thus, the drill bit utilized to drill the wellbore can begin its drilling operation above the float equipment and successfully drill a wellbore below the casing having a diameter greater than the inner diameter of the casing.

Abstract: The drilling apparatus includes a safety sub mountable to the drill string outer end to retain the combination of an overshot assembly and an overshot adaptor extending within the drill string outer end during a drilling operation and preventing the drilling tool moving out of the drill string until the sub is removed. The overshot assembly has a fluid seal between the overshot tube and the drill string and a fluid bypass channel with valve means for blocking axial outward flow through the channel when the overshot adaptor is separated from the overshot assembly and when connected thereto, retaining the valve means in an open condition. When the overshot adaptor is removed from the overshot assembly, the overshot assembly is fluidly propellable to the bit end. A disconnect tool facilitates the removal of the adaptor from the sub.

Abstract: A drill pipe protector assembly for providing hydraulic lift and improved sliding lubrication to a drill string. The protector defines a tubular sleeve that is attached to a section of drill pipe and resides over the outer diameter of the drill pipe while moving within an associated well casing or well hole. The sleeve is adapted to provide hydraulic lift and sliding lubrication relative to the well casing and thus, increase the proclivity of the drill pipe to slide down the hole while also reducing the development of cutting dams. The sleeve includes a plurality of radially oriented openings which direct drilling mud from the annular space between the sleeve and drill pipe to the annular space between the sleeve and the casing or outer well wall. The sleeve also includes a plurality of wedge shaped longitudinal channels in communication with the radial openings.

Abstract: A pressure and temperature core sampler comprises a tool for recovering cores specifically enabling the evaluation of methane hydrate resources. Because methane hydrate tends to decompose under conditions of pressure decrease and/or temperature increase as the samples are retrieved to the surface, a coring tool in accordance with the present invention provides a self-contained system for retrieving core samples at or near in situ pressure while cooling the core sample. The coring tool is preferably a wire line retrievable device that provides for nearly continuous coring during the drilling operation.

Abstract: A downhole drilling apparatus for interconnection in a casing or liner string having a drill bit disposed thereon for enabling the drilling of intersecting wellbores without removal of the drill bit is disclosed. In a disclosed embodiment, the apparatus comprises a housing having a window. A whipstock is disposed within the housing. Between the window and the whipstock is a filler. The whipstock and the filler define a central bore providing a fluid path through the apparatus. A back pressure valve may be disposed within the central bore to prevent back flow of fluids through the apparatus. Once the total depth of an initial wellbore is reached, the casing or liner string, including the apparatus, may be cemented in place. Thereafter, an intersecting wellbore may be drilled by laterally deflecting a second drill bit with the whipstock through the window of the housing.

Abstract: A method of drilling and installing a pile in ground comprising the steps of providing a pile, providing a drill bit at an end of the pile rotatable relative to the pile; engaging the ground with the drill bit, and rotating the drill bit relative to the ground and the pile generating a hole into which the pile is received.

Abstract: A downhole drilling apparatus for interconnection in a casing or liner string having a drill bit disposed thereon for enabling the drilling of intersecting wellbores without removal of the drill bit is disclosed. In a disclosed embodiment, the apparatus comprises a housing having a window. A whipstock is disposed within the housing. Between the window and the whipstock is a filler. The whipstock and the filler define a central bore providing a fluid path through the apparatus. A back pressure valve may be disposed within the central bore to prevent back flow of fluids through the apparatus. Once the total depth of an initial wellbore is reached, the casing or liner string, including the apparatus, may be cemented in place. Thereafter, an intersecting wellbore may be drilled by laterally deflecting a second drill bit with the whipstock through the window of the housing.

Abstract: A pressure and temperature core sampler comprises a tool for recovering cores specifically enabling the evaluation of methane hydrate resources. Because methane hydrate tends to decompose under conditions of pressure decrease and/or temperature increase as the samples are retrieved to the surface, a coring tool in accordance with the present invention provides a self-contained system for retrieving core samples at or near in situ pressure while cooling the core sample. The coring tool is preferably a wire line retrievable device that provides for nearly continuous coring during the drilling operation.

Abstract: A down hole running tool 14 travels in a first direction through a drill pipe for installing bit segments 18 at the end of a drive sub 12 attached to the drill pipe. The tool 14 includes a first portion 82 and a second portion 84 which is retractably coupled to a leading end of the first portion 82. The first portion 82 includes a tubular extension 134 which receives a spigot 136 that extends from an upper end of the second portion 84. A pin 138 extends transversely through the tubular extension 134 and resides within opposing slots 140 formed in the spigot 136. There is a stepped reduction in the internal diameter at the lower end of the tubular extension 134 so as to form a cup-like structure 146. A spring 168 is disposed about the spigot 136 and has an upper end seated in the cup-like structure 146 and a lower end bearing against an upper face 170 of the second portion 84. The spring 168 is biased so as to push the first and second portions 82 and 84 apart in the longitudinal direction.

Abstract: A drilling liner having a core bit at its bottom end is carried along with a pilot bit on an inner bottom hole assembly driven by a downhole mud motor. In one embodiment, the motor is powered by mud carried by an inner string. Alternatively, the inner string may be omitted and the flow of mud through the liner powers the motor: this requires a locking tool for locking the motor assembly to the outer assembly. Once an abnormally (high or low) pressured zone has been traversed, the liner is set as a casing, the inner assembly is pulled out, and drilling may be resumed using a conventional tool. Directional drilling is accomplished by having an MWD device for providing directional information and having directional devices on the inner and outer assembly. These include retractable steering pads. Expandable bits, under-reamers and jetting nozzles may also be used in the drilling process.

Abstract: A sleeve (10) comprises a cylindrical member (12) provided at one end (14) with a pair of opposing tapered peaks (16) and (18). Peak (16) is higher (longer) than peak (18). Sleeve (10) is retained within a drive sub (26) of a ground drill and is constrained to move linearly along the drive sub (26). The peaks (16) and (18) cooperate with latch dogs (20) and (22) which are evenly spaced about and extend radially from a running tool (24). When the running tool (24) travels down the drive sub (26) and enters the sleeve (10), one of the latch dogs (20, 22) will strike one of the peaks (16) and (18) causing the tool (24) to rotate toward a predetermined rotational position. Because the peaks (16) and (18) are at different heights, latch dogs (20) and (22) cannot simultaneously contact the very top of each peak (16) and (18). If latch dog (20) strikes the top of peak (16), it will then slide down one of the sides of that peak causing the tool (24) to rotate.

Abstract: A retractable drill bit system for a ground drill includes drill bit assembly, a bit assembly sleeve, and a transport member. The drill bit assembly is engagable with a drive sub attached to the bottom of the ground drill with the drill bit assembly being selectively expandable and collapsible between a transport position in which the drill bit assembly is transported through the ground drill by the sleeve and transport member and a cutting position in which the drill bit assembly locks into the drive sub and cuts the hole. The drill bit assembly in the cutting position is able to cut a hole substantially greater than the diameter of the ground drill itself. The drill bit assembly includes a circular bit attached at a lower most end of the sleeve and bit segments retained in slots formed in the sleeve. Each segment is provided with a lever that extends radially inwardly of the sleeve and engages the transport member.

Abstract: In a process for drilling, in particular rotary percussion or percussion drilling, and lining holes in the ground or rocks, a hole is percussion and/or rotation drilled by a cutter mounted on boring rods and a lining is formed by a jacket tube. During drilling, at least one jacket tube coupled to the cutter is drawn in the axial direction by the cutter into the bore hole and once drilling is finished, the cutter is at least partially removed from the jacket tube together with the boring rods. In a device for drilling, in particular percussion or rotary percussion drilling, and lining holes in the ground or rocks, a cutter mounted on boring rods drills a bore hole by percussion and/or rotary drilling. The cutter is divided in the radial direction.

Abstract: A retraction system allows disengagement of retrieval latch dogs of a down hole running tool from a bit locking sleeve. The locking sleeve is slidably retained within a drive sub and includes a pair of slots which are engaged by the retrieval latch dogs when the tool is used to retrieve bit segments from the drive sub. The retraction system includes a sleeve which is slidably mounted on a main body of the tool and spring which is biased to push the sleeve over the retrieval latch dogs. The sleeve has a pair of diametrically opposed slots through which the retrieval latch dogs can extend for contacting the inner surface of the drive sub. The retraction system also includes a length of the inner surface of the drive sub which is made of progressively reducing diameter in the direction of retraction of the tool from the drive sub. The upper end of each slot is provided with a bevel for directing the retrieval latch dogs in the inward direction.

Abstract: A core barrel having an inner tube for coring and, alternately, a center plug assembly for closing the throat of the core bit at the bottom of the assembly for drilling in lieu of coring. The inner tube assembly and plug assembly are disposable and retrievable through the drill string on a wireline using an overshot. The core bit is of a stabilized, preferably anti-whirl, design and may be a low-invasion core bit used in cooperation with a low-invasion coring shoe. A logging tool and data transmission assembly may be incorporated in the plug assembly for logging while drilling. Alternatively, sensors for logging borehole parameters and a data transmission assembly may be incorporated in the inner tube assembly, in the wall of the core barrel, above the core barrel, or in a combination of such locations.

Abstract: A method and liner assembly for drilling into unstable or depleted formations is provided that maintains control of the wellbore against caving such as where unconsolidated formations are penetrated and/or minimizes fluid losses such as to underpressured formations where differential pressures exist. The method and liner assembly herein includes the provision of a liner having a portion thereof that is drillable so that after setting of the liner, drilling can continue deeper into the unstable formations with minimal damage to the bit used to drill out the liner drillable portion. In one form, the liner has a shoe that includes cutter mounting blades, each having a set of cutters thereon. Relief slots are formed in the blades between cutters so that as the shoe and its blades are being drilled, the drill bit will cut through the slots, releasing the shoe cutters for transport up to the surface by the drilling fluid thereby minimizing damaging contact of the bit with the shoe cutters.

Abstract: A retractable drill bit system 10 comprises a drive sub 18 which is adapted for connection to a lower end of a drill 12, a tool 20 for installing and retracting drill bit segments 22 from the drive sub 18; and an insert 24 for selectively locking the bit segments 22 to an end of the drive sub 18 and releasing the bit segments 22. A plurality of recesses 5B are formed about an inner circumferential wall at one end of the drive sub 18 and a landing seat 32 formed about the inner wall upstream of the recesses 58. The area of the interior wall between the landing seat 32 and recesses 58 is profiled with a series of tapered and level surfaces. The tool 20 includes a slidable cradle 176 extending from one end about which the bit segments 22 are held during installation and retrieval. The bit segments 22 being held in place about the cradle by an elastic band 198.

Abstract: Methods and related equipment for drilling a wellbore in subterranean formations whereby a drill bit is attached to one end of a first conduit string, such as a casing string which is not usually used for drilling, and advancing the first conduit string and the drill bit into the subterranean formation to extend an existing wellbore, cleanout the wellbore or create a new lateral wellbore. This advancement is stopped and steps are taken to create a longitudinal opening through the drill bit. Thereafter, a second conduit string is advanced through the opening in the drill bit and into the subterranean formation to further extend, cleanout or create the lateral wellbore.

Abstract: A method of sinking a bore hole in underground formations which have at least one special stratiform formation which features vastly differing formation pressures in respect to a formation adjacent to it in the sinking direction and in which a drilling tool carried at the bottom end of a drill line and having a drill bit driven by a deep drilling motor drills out a first part of a bore hole which extends to a point close to the boundary area of the special formation, characterized in that upon subsequent sinking of a further part of the bore hole by the casing string which passes through at least one special formation, a tubular outer casing with a bottom end carrying a driven drill head is entrained, the bore hole being lined by this, at least in the region of the special formation.

Abstract: An augerless boring system uses a relatively slender drill steel pipe attached at a front end to a large tubular hammer. The hammer holds different drill bits. The drill steel and the hammer are located inside a casing and driven along with the casing by a power and advance unit. The hammer extends through a front stabilizer head attached to the front end of the casing. A stabilizer head improves drill bit control while supporting the boring assembly in the casing. The stabilizer head includes multiple stabilizer bars extending lengthwise along the inside of a stabilizer casing. A special thrust adapter is used for pushing the casing in a forward direction and attaches to a size adapter that provides forward pressure against substantially the entire rear end of the casing. The thrust adapter in combination with the size adapter provides even distributed pressure to the rear end of the casing for more effective thrust of the casing into a bore hole.

Abstract: A drilling apparatus adapted to be fed into a hole to be drilled and extendable in a longitudinal direction includes a casing and a drilling unit. A drilling head of the drilling unit includes a first drilling unit for drilling a center hole and a second drilling unit for reaming the center hole for the casing, the first drilling unit attachably connected to the second drilling unit at the drilling head. A counterpart assembly transmits rotational and impact movement from the first to the second drilling unit. A coupling assembly connects the second drilling unit with a head of the casing such that the second drilling unit freely rotates centrically around a longitudinal axis. A flushing unit for removal of drilling waste comprises at least one first passage extending through the first drilling unit to a drilling point, and communicates with at least one flow channel for transferring flushing medium to a drilling surface and the drilling point.

Abstract: When drilling in soil and simultaneous loading of casing tube, it is desirable to be able to use casing tubes of plastic material such as PEH-plastic. This is made possible by a special design of a casing shoe giving a strong joint between the casing shoe and the casing tube. The casing shoe is made of metal and has a part which is perforated with holes filled with the plastic material. Tube couplings between the casing tubes can also be joined to the tubes in the same way as the casing shoe. In other words, they can be made of metal and each have one part perforated with holes filled with the plastic material.

Abstract: An apparatus and a method for installing open-ended tubular members axially into the earth by simultaneously or sequentially driving, drilling, and jetting. A drilling string assembly is located inside the tubular member, but is supported independently from the tubular member. The position of the drill bit on the lower end of the drilling string assembly relative to the lower end of the tubular member may be adjusted so as to control the rate of penetration of the tubular member into the earth.

Abstract: Apparatus and method for simultaneously and separately emplacing two streams of different materials through a drillstring in a borehole to a downhole location for lost circulation control. The two streams are mixed outside the drillstring at the desired downhole location and harden only after mixing for control of a lost circulation zone.

Abstract: This invention relates to a chuck assembly for a drill box of a mine drill for releasably securing a mining tool including a working end and a depending rod-like member for roof bolting and roof and face drilling operations and a method of using the chuck assembly. The drill box includes a source of rotary power and a drive member operatively connected to the source of rotary power to rotatably drive the chuck assembly. The chuck assembly includes a spindle, a collet closer and a collet. The spindle is operatively connected to the drive member and has a sleeve of a cylindrical shape including a threaded collar end and a bottom end and an opening extending a selected distance from the collar end to the bottom end. The collet closer includes an annular housing having an aperture threaded for threadingly engaging the threaded collar end of the spindle.

Abstract: The present invention comprises a novel method and apparatus for sinking drill holes in underground rock formations while generating drill cores as rock samples. More particularly, the present invention discloses a method and apparatus which allows for an expanded analysis of ground formations over a larger area through the extraction of drill cores as rock samples. The method and apparatus herein disclosed allows one to drill a number of core shaft sections from the base of a main shaft section in various directions in order to obtain a number of sample cores.

Abstract: The present invention comprises a drilling tool including a retractable pilot drilling unit driven by a fluid operated motor, the motor comprising a stator mounted on the interior of a tubular outer housing and a rotor mounted on the exterior of a tubular inner housing axially supported in said outer housing and rotationally free with respect thereto. The pilot drilling unit is rotationally fixed within the inner housing, but axially moveable therewithin so that pressure of drilling fluid used to drive the motor will also act on reaction surfaces of the pilot drilling unit to urge it axially forward. The top of the pilot drilling unit includes a fishing head for retracting the pilot drilling unit from the drilling tool, and reinserting it therein.

Abstract: The present invention comprises a novel method and apparatus for forming a perimeter lined, generally horizontally directed drill hole in a variety of soil formations. More particularly, the present invention discloses a method and apparatus for horizontal drilling which allows for the preparation of reinforced drill holes of a small diameter and precise heading by the use of a directed drilling tool seated within a mantle tube and the simultaneous advancement into various soil formations of this combination.

Abstract: Drill tools with eccentric bits for drilling a hole having a large diameter generally include a bit for swinging out to an eccentric position for drilling, and for swinging into a non-eccentric position for removal from a tubular casing. Relatively complicated structures are required for effecting bit movement, and it is often difficult to remove the bit for replacement or repair.

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: In well drilling, and in particular the horizontal drilling field, a simultaneous drilling and casing device is provided. A drill string driven in rotation by a revolving table has at its end a drilling tool 28 driven by a bottom motor 22 and, in its intermediate part, a drive connection 10 to which the rear end 1a of a casing section 1 is screwed, whose front end is provided with an abrasive material ring 3. The length of the part of the drill string separating the connection 10 from tool 28 is substantially equal to the length of section 1. The casing 1 driven by the drill string at the speed of rotation of the revolving table cuts its own way during the drilling.

Abstract: An apparatus for propelling a plurality of pipes arranged in series comprises basic thrusting means for generating a thrust to be applied to the pipes and intermediate thrusting means for receiving the thrust from the basic thrusting means and applying the received thrust to one of the pipes. The intermediate thrusting means includes a press head provided with a portion displaceable to a position where the portion is capable of abutting against the rear end face of one of the pipes when the intermediate thrusting means is advanced while displaceable to another position where the portion does not interfere with the advance of the following pipes when the intermediate thrusting means is removed and an intermediate body extending rearward from the press head such as to receive the thrust from the basic thrusting means and apply the received thrust to the press head.

Abstract: In a subterranean drilling operation, a drill stem and drill bit are advanced downwardly while conducting compressed air downwardly through the drill stem. A minor part of the air flow is discharged from the drill bit downwardly against the sensible overburden, and a major part of the air flow is discharged upwardly through passages in the drill stem. A casing is disposed around the drill stem and advanced therewith so that the sensible overburden is shielded from the air discharged from the upwardly directed passages. The upwardly directed passages contain removable inserts which can be exchanged for different inserts in order to vary the amount of air discharged from the upwardly directed passages, and thereby vary the amount of air discharged downwardly from the drill bit against the overburden. In that way, the amount of air acting against the overburden can be adapted to the type of material in the overburden in order to control the amount of disruption to the overburden.

Abstract: Apparatus for driving casing, piles, or conductor pipe into the ground comprises in combination; an external reciprocal impact driving means supported atop the conductor pipe, internal rotatable drilling means supported within the conductor pipe, and means associated therewith for introducing air and water under pressure for creating a pressure differential to evacuate the drilling debris and cuttings to the surface. The drilling means is supported within said conductor pipe at the bottom portion thereof near the point of least energy absorption and rebound. The driving and drilling operations may be performed simultaneously or sequentially.

Abstract: A method is disclosed for installing and retaining a conductor between a surface terminal and a subsurface location in a drill string used to drill a well. One end of the conductor is lowered into the drill string and is anchored to the drill string of a subsurface location. The upper end of the conductor is taken in from the surface until the conductor is tensioned to a selected amount. The upper end of the conductor is then connected to the surface terminal. As each drill pipe section is added to the drill string to advance the depth of the well, the tension of the conductor is controlled to reduce fatigue failure of the conductor. In one embodiment of the invention, the tension of the conductor is controlled by connecting a conductor section of a selected length between the surface terminal and the upper end of the conductor.