Abstract: A drilling system includes a steerable bottomhole assembly (BHA) having a steering unit and a control unit that provide dynamic control of drill bit orientation or tilt. Exemplary steering units can adjust bit orientation at a rate that approaches or exceeds the rotational speed of the drill string or drill bit, can include a dynamically adjustable articulated joint having a plurality of elements that deform in response to an excitation signal, can include adjustable independently rotatable rings for selectively tilting the bit, and/or can include a plurality of selectively extensible force pads. The force pads are actuated by a shape change material that deforms in response to an excitation signal. A method of directional drilling includes continuously cycling the position of the steering unit based upon the rotational speed of the drill string and/or drill bit and with reference to an external reference point.

Abstract: Steerable drilling systems for facilitating drilling according to a prescribed, three-dimensional trajectory are described. Steering may be achieved using passive actuators which require little or no power. For example, damping elements which couple a drill bit to a drill collar can be used to tilt the drill bit with respect to the drill collar. Alternatively, rotary cutting elements disposed on the drill bit may be used to control the force between the drill bit and the formation at different axial locations. The passive elements used to control the tilt or rotation of the rotary cutting elements are actuated in a certain pattern, e.g., geostationary, in order to achieve a desired deviation of the well bore while drilling ahead. One way to achieve this is through the use of field-sensitive materials, e.g. magnetorheological (MR) fluids, that change viscosity in response to an applied magnetic field.

Abstract: Methods and apparatus for navigating a subterranean tool comprising a body member and a head member steerably associated with the body member. A determining unit is configured to determine a transversal target position of a nose of the head member relative to the body member and a steering unit is configured to steer the head member relative to the body member so that the nose of the head member is located at the transversal target position.

Abstract: A drilling rig for drilling an underground borehole (5) into a seam (4) uses coiled metal tubing (8) fed by a tractor unit (11) from a drum (7) to provide a thrust force to a drilling head. The drilling head has a bent-sub assembly giving an angle of deviation which is controlled by rotating the coiled metal tubing in the borehole by way of rotation of the drum (7) in the frame (12) about the axis of the tube in the borehole (5).

Abstract: A system for steering the direction of a borehole advanced by cutting action of a rotary drill bit by periodically varying action of a drill bit while continuously rotating a drill string to which the drill bit is operationally attached. The steering system comprises a bit perturbation device cooperating with a bent housing subsection and operationally connected to the drill string and to the drill bit. Drill bit action is varied by periodic varying the rotation speed or rate of penetration of the drill bit. Periodic drill bit action results in preferential cutting of material from a predetermined arc of the borehole wall which, in turn, resulting in borehole deviation.

Abstract: The invention provides rotary steerable devices and methods for use of rotary steerable devices. One aspect of the invention provides a rotary steerable device including: a cylinder configured for rotation in a wellbore, the cylinder having a slot and a gauge; and at least one cam received in the slot. The cam is configured for selective actuation between a first position, wherein the cam lies within the gauge of the cylinder, and a second position, wherein the cam is displaced out of the gauge of the cylinder.

Abstract: A bottomhole assembly (BHA) coupled to a drill string includes one or more controllers, and a hole enlargement device that selectively enlarges the diameter of the wellbore formed by the drill bit. The hole enlargement device includes an actuation unit that may move extendable cutting elements o the hole enlargement device between a radially extended position and a radially retracted position. The actuation unit may be responsive to a signal that is transmitted from a downhole and/or a surface location. The hole enlargement device may also include one or more position sensors that transmit a position signal indicative of a radial position of the cutting elements. In an illustrative operating mode, one or more operating parameters of the hole enlargement device may be adjusted based on one or more measured parameters. This adjustment may be done in a closed-loop or automated fashion and/or by human personnel.

Abstract: In one aspect of the present invention, a drill bit has a jack element that is substantially coaxial with an axis of rotation of the drill bit and the jack element has an asymmetrical distal end that extends beyond a working face of the drill bit. A turbine is located within a bore formed in the drill bit and a flow valve is actuated by the turbine. The flow valve is adapted to route a drilling fluid in the bore into a porting mechanism adapted to extend the jack element farther beyond the working surface of the drill bit. The turbine is also adapted to rotate the jack element at variable speeds.

Abstract: The present invention relates to systems and methods for controlling downhole motors. One aspect of the invention provides a valve-controlled downhole motor including: a downhole motor and a spool valve. The downhole motor includes a sealed chamber having a first port and a second port, a stator received within the sealed chamber, and a rotor received within the stator. The spool valve includes a barrel and a spool received within the barrel. The barrel includes an inlet port, an exhaust port, a first feed port, a second feed port, a first return port, and a second return port. The inlet port is located in proximity to the first feed port and second port. The exhaust port is located in proximity to the first return port and the second return port. The spool includes a first gland and a second gland.

Abstract: One embodiment includes an apparatus comprising a steerable well bore drilling tool having a main tool body. The steerable well bore drilling tool includes an inertial measurement unit to output a measurement used to determine an azimuthal deviation and inclination of the steerable well bore drilling tool during a drilling operation.

Abstract: Earth-boring tools comprise a shank comprising a distal connector including a set of threads thereon and a bit body comprising a shank connector, also comprising at least one set of threads thereon. The set of threads on the distal connector and the at least one set of threads on the shank connector are at least substantially bound together. Methods of forming such earth-boring tools are also disclosed, as well as methods of securing a bit body of an earth-boring tool to a shank.

Abstract: The drill bit shaft structure for an excavation apparatus has a thin-walled shaft portion formed on a hollow drill bit shaft. The thin-walled shaft portion has a thinner wall than that of shaft portions of the hollow drill bit shaft adjacent to both ends of the thin-walled shaft portion. A cylindrical body provided with an adjustable joining structure is disposed so as to envelop the thin-walled shaft portion. Both ends of the cylindrical body are connected to the shaft portions of the hollow drill bit shaft adjacent to the both ends of the thin-walled shaft portion. The direction of excavation is controlled by bending the thin-walled shaft portion and the cylindrical body.

Abstract: The present disclosure relates to an auger boring machine for boring through the earth. The auger boring machine includes a cutting head for engaging a working face of the earth to cut a bore. The cutting head is rotatable about a drive axis so as to cut the earth at the working face. The auger boring machine further includes an auger that is rotatable about the drive axis for transporting spoil resulting from the operation of the cutting head away from the cutting head. Additionally, the auger boring machine includes a casing housing the auger which is urged to move into the bore behind the cutting head. The cutting head and the auger are movable along the drive axis relative to the casing. Furthermore, the auger boring machine includes a steering member positioned near the cutting head for directing movement of the casing into the bore in a steered direction transverse to the drive axis.

Abstract: A system of components and a method is provided for radial and level drilling and completion with an ultra-short radius which includes a deflecting drill tool assembly and a level drill tool assembly. The deflecting drill tool has a deflecting rotary assembly, flexible drill pipe, directional follow-up tube, tail tube for deflecting drill tool, and drill pipe nipple joints. The level tool has a level rotary assembly, the flexible drill pipe, quick couplings, the directional follow-up tube, a tail tube for level drill tool, the drill pipe nipple joint, an adjusting nipple joint, a recessed left hand thread bushing, and convex left hand thread coupling. A triangle backing block is installed on outside of a casing of the deflecting rotary assembly. Splines matched with each other are provided at the level rotary assembly and the flexible drill pipe. The tail tube for level drill tool has a recessed left hand thread bushing and convex left hand thread coupling.

Abstract: A drilling system, comprising: a non-rotating conveyance system; a tool connected to the non-rotating conveyance system and including anchors by which the tool can be anchored in position when located in a borehole; a drill bit connected to the tool; a motor for rotating the drill bit; and a directional control system interposed between the tool and the drill bit; wherein, in use, with the drilling system located in a borehole, the directional control system can be operates so as to displace the drill bit away from the axis of the borehole.

Abstract: A tilted drive sub is disclosed with a center line of the internal diameter (ID) offset at an angle from the center line of the outer diameter (OD) starting at a point near to a top end of the tilted drive sub. This results in the ID being at an angle to the OD, with the OD of the tilted drive sub remaining straight. The offset ID has the same threads of a mud motor without a tilted drive sub. The tilted drive sub replaces the outer bearing housing of a normal performance mud motor.

Abstract: In one embodiment of the invention, a downhole tool string component comprising a through bore running there through formed to accept drilling fluid. At least one mechanical actuation device is also disposed within the through bore. A guide channel is disposed within the through bore and comprises a geometry shaped to conduct the at least one mechanical actuation device. A switch is disposed within the guide channel in an original position and actuatable by the at least one mechanical actuation device to a subsequent position. A resettable mechanism is in contact with the switch wherein the resettable mechanism returns the switch to its original position. A receptacle may also be disposed within the through bore comprising a geometry shaped to accept the at least one mechanical actuation device.

Abstract: The present invention provides apparatus and methods for controlled steering. One embodiment of the invention provides a bit body comprising a trailing end, a pilot section, and a reaming section. The trailing end is adapted to be detachably secured to a drill string. The pilot section is located on a leading, opposite end of the bit body. The reaming section is located intermediate to the leading and trailing ends. The pilot section comprises at least one steering device for steering the pilot section of the bit body, thereby steering the entire bit body. Another embodiment of the invention provides a wellsite system comprising a drill string; a kelly coupled to the drill string; and a bit body as described above. Another embodiment of the invention provides a method of drilling a curved borehole in a subsurface formation.

Abstract: A rotary steerable apparatus is provided having an actuator for pushing the bit or pointing the bit that includes a shape memory alloy. An elongated form of the alloy, such as a wire or rod, is employed in a mechanism that applies force in a direction transverse to the wellbore in response to a change in length of the alloy. Temperature of the alloy is controlled to change shape and produce the desired force on pads for operating the apparatus. The apparatus may be used with downhole power generation and control electronics to steer a bit, either in response to signals from the surface or from downhole instruments.

Abstract: A method for forming a subsurface wellbore is disclosed. The method includes operating a drilling string in a first direction of rotation. A first motor located near the end of the drilling string is operated in a direction of rotation opposite that of the drilling string. A drill bit is rotated using a second motor that is coupled to the first motor.

Abstract: A drilling apparatus controls or eliminates reaction torque from drill bits thereby preventing loss of penetration due to undesired rotation of the drilling apparatus or controls drilling direction by intentionally manipulating reaction torque thereby inducing desired drill bit walk. The drilling apparatus has a concentrically divided drill bit in which an inner drill bit rotates simultaneously in the opposite direction from an outer drill bit. The inner drill bit can be moved axially forward from or back toward the outer drill bit. Forces produced by the inner and outer drill bits are controlled to eliminate or adjust reaction torque.

Abstract: In one aspect of the invention a tool string steerable system has a drill bit body with a working face. An indenter protrudes from the working face and the indenter is rotational fixed to a tool string component above the drill bit body. The indenter is rotationally isolated from the drill bit body.

Abstract: A downhole tool string component, having a first rotor secured within a bore of the component and connected to a gear assembly, the gear assembly being connected to a second rotor. The gear assembly has a gear ratio adapted to rotate the second rotor faster than the first rotor. The second rotor is in magnetic communication with a stator which has an electrically conductive coil, the electrically conductive coil being in communication with a load.

Abstract: Apparatus and methodology is provided for directional drilling which avoid the effects of static friction between the drill string and the borehole. The drill string is rotated continuously in one direction during rotating drilling and during steering. During steering, the rotary speed of the drill string is varied within a revolution and substantially similarly for each of a plurality of subsequent revolutions. The drill string is rotated very slowly when oriented at or near the desired orientation to achieve the desired change in direction and then rotated much faster during the balance of each revolution. This angular velocity profile results in drilling at or near a desired orientation for a high percentage of the time it takes for each revolution. Changes in an effective tool-face orientation can be effected by shifting the phase of the velocity profile.

Abstract: A method for determining wellbore trajectory includes determining survey parameters in the wellbore; measuring force parameter(s) in the wellbore; and correcting the survey parameters using the measured force parameter(s). The downhole measured force parameters may include forces associated with an operation of a steering device such as an internal reaction force, and/or a bending moment. In variants, the method may include measuring a wellbore temperature; measuring a wellbore parameter in addition to the temperature; and correcting a survey parameter using the measured parameter and the measured temperature. These methods may include correcting survey parameters using measured wellbore diameters. Also, a processor in the wellbore may be programmed to perform the correction while in the wellbore and/or control a steering device using measurements provided by a sensor for measuring internal reaction forces.

Abstract: A method for the directional control of a rock-drilling ma-chine, the drilling unit (1) of the rock-drilling machine, which is located in a borehole (2), comprising at least a pi-lot drill bit (6) or an underreamer drill bit (8), the drill bit(s) (6, 8) being driven by an electric motor (10) via a gearbox (12), and the drill bit(s) (6, 8) being moved into the rock (3) by means of a feeding rod (4) extending from a feeding machine at the outside the borehole (2), and the drill bit(s) (6, 8), gearbox (12) and motor (10) being pivoted in a controlled manner about a steering axis (18) which is approximately perpendicular to the center axis (26) of the feeding rod (4).

Abstract: In one aspect of the present invention, a drill string has a drill bit with a body intermediate a shank and a working face. The working face has at least one cutting element. A jack element is disposed within the drill bit body and has a distal end substantially protruding from the working face. The distal end has a primary deflecting surface having an angle relative to a central axis of the jack element of 15 to 75 degrees.

Abstract: The present invention relates to a portable, directional electrocrushing drilling apparatus and method.

Abstract: The invention concerns a drilling tool steering device, characterized in that it contains, consecutively from upstream to downstream, a main body (1) and a steerable housing (2), joined respectively by at least one connection of pivot, sliding pivot, ball joint or annular linear type forming a first bearing (4), and at least one pivot connection forming a second bearing (5), to a bendable or flexible transmission shaft (3) which crosses them longitudinally, while a connection of pivot, sliding pivot, annular linear or ball joint type forming a third bearing (6) between said transmission shaft and the main body (1) is arranged in proximity to the end of said main body situated in the direction of the steerable case, and while steering is carried out thanks to means acting as a deflection system (7) for the essentially radial relative displacement of the main body (1) in relation to the steerable housing (2) in proximity to their interface, the said main body being optionally equipped on its periphery with bear

Abstract: A communication system for a casing while drilling system is provided. The casing while drilling system is adapted to advance a bottom hole assembly into a subsurface formation via a casing. The communication system comprises a high frequency modulator and a transducer. The modulator is positioned in the bottom hole assembly and adapted to generate a mud pulse by selectively restrict mud flow passing therethrough. The transducer is adapted to detect the mud pulse generated by the modulator.

Abstract: A microtunnelling apparatus and system that includes an external drive system having rotational and linear thrust drive means, a drill head section having drill rotor and drill rod and connecting to intermediate drill rods allowing extension of the boring hole created by the drill head section driven by the drive system. The drill head includes a modular construction having a plurality of circular disc like elements, a bearing module, a steering module, a spacer module, and a mounting module, for axial alignment and abutment and mounting within a cylindrical steering shell. Directional steering of the drill head includes a plurality of substantially radially extending channels in steering module, each with an hydraulically movable protuberance movable by control means to redirect the outer steering casing and thereby redirect the drill head section mounted on the distal end of the drill rods.

Abstract: Drilling means for directional drilling in a bore hole comprising a drill pipe and a drilling head, including a slippable clutch device linking the drill pipe and said drilling head such that torque due to rotation of said drill pipe can be controllably applied to said drilling head through at least partial engagement of said clutch, and control means operable to sense an actual orientation angle of said drilling head and compare said actual orientation angle with a required orientation angle adjustably set in said control means and to control said slippable clutch such that when the actual orientation angle and the required orientation angle are the same, the slip torque of the slipping clutch equals the motor reaction torque, so maintaining the orientation angle of the drilling tool at said required orientation angle.

Abstract: A well system includes a valve interconnected in a casing string and selectively configurable between first and second configurations via a line external to the casing string, the valve in the first configuration being operable to selectively permit and prevent fluid flow between the casing string exterior and interior, and in the second configuration to selectively filter and prevent fluid flow between the casing string exterior and interior. A method of selectively stimulating a formation includes: positioning a casing string in a wellbore intersecting the formation, the casing string including a valve operable via an external line to selectively permit and prevent fluid flow between the casing string interior and exterior; and stimulating an interval set of the formation by opening the valve, flowing a stimulation fluid from the casing string into the interval set, and then configuring the valve to filter formation fluid which flows into the casing string.

Abstract: In one aspect of the present invention, a drilling assembly comprises a drill bit comprising a bit body intermediate a working face and a shank. An indenting member adapted to guide the drill bit protrudes from the working face. A flexible portion is disposed above the bit body.

Abstract: A bottom hole assembly connected to coiled tubing to create an acid tunnel in a wellbore formation. High pressure acid is pumped down the coiled tubing and out a nozzle located at the end of the bottom hole assembly. The bottom hole assembly includes a first reversible knuckle joint and a second reversible knuckle joint to properly position the nozzle against the wellbore and to allow the assembly to adjust its angle as it initiates and moves through the lateral tunnel. The two reversible knuckle joints increases the radius of curvature of the bottom hole assembly while providing a sufficient attack angle for the nozzle against the wellbore. The two knuckle joints may be adjusted in response to loads applied on the assembly as the assembly moves through the lateral tunnel.

Abstract: One embodiment includes an apparatus comprising a steerable well bore drilling tool having a main tool body. The steerable well bore drilling tool includes an inertial measurement unit to output a measurement used to determine an azimuthal deviation and inclination of the steerable well bore drilling tool during a drilling operation.

Abstract: Methods and apparatus for using a quill to steer a hydraulic motor when elongating a wellbore in a direction having a horizontal component, wherein the quill and the hydraulic motor are coupled to opposing ends of a drill string, by monitoring an actual toolface orientation of a tool driven by the hydraulic motor via monitoring a drilling operation parameter indicative of a difference between the actual toolface orientation and a desired toolface orientation, and then adjusting a position of the quill by an amount that is dependent upon the monitored drilling operation parameter.

Abstract: In one aspect of the invention a drill bit assembly has a body portion intermediate a shank portion and a working portion, the working portion having at least one cutting element. A shaft is supported by the body portion and extends beyond the working portion. The shaft also has a distal end that is rotationally isolated from the body portion. In another aspect of the invention, a method for steering a downhole tool string has the following steps: providing a drill bit assembly attached to an end of the tool string disposed within a bore hole; providing a shaft extending beyond a working portion of the assembly; engaging a subterranean formation with a distal end of the shaft; and angling the drill bit assembly with the shaft along a desired drilling trajectory.

Abstract: One embodiment includes an apparatus comprising a steerable well bore drilling tool having a main tool body. The steerable well bore drilling tool includes an inertial measurement unit to output a measurement used to determine an azimuthal deviation and inclination of the steerable well bore drilling tool during a drilling operation.

Abstract: In one aspect of the invention a drill string has a rotary valve disposed within its bore. The valve has a first disc attached to a driving mechanism and a second disc axially aligned with and contacting the first disc along a flat surface. Each disc has a port adapted to align with each other periodically when the discs rotate relative to one another. The aligned ports are adapted to direct fluid to at least one nozzle disposed in a working face of a drill bit of the drill string.

Abstract: This invention relates to a steering assembly and to a steering component, suitable for use in drilling operations for oil and gas. The steering assembly comprises a downhole motor which can rotate the drill bit, and a steering component. The steering component has a shaft and a set of elements for engaging the borehole in use. The shaft has a longitudinal axis. The set of elements has a centerline and is movable relative to the shaft between a first position in which the centerline is offset from the longitudinal axis of the shaft by a first distance, and a second position in which the centerline is offset from the longitudinal axis of the shaft by a second distance. In use in drilling operations, movement of the set of elements from the first position to the second position alters the degree of curvature of the drilled hole.

Abstract: Apparatus and methodology is provided for directional drilling which avoid the effects of static friction between the drill string and the borehole. The drill string is rotated continuously in one direction during rotating drilling and during steering. During steering, the rotary speed of the drill string is varied within a revolution and substantially similarly for each of a plurality of subsequent revolutions. The drill string is be rotated very slowly when oriented at or near the desired orientation to achieve the desired change in direction and then rotated much faster during the balance of each revolution. This angular velocity profile results in drilling at or near a desired orientation for a high percentage of the time it takes for each revolution. Changes in an effective tool-face orientation can be effected by shifting the phase of the velocity profile.

Abstract: A system for steering the direction of a borehole advanced by cutting action of a rotary drill bit by periodically varying the rotation speed of the drill bit. The steering system comprises a motor disposed in a bent housing subsection and operationally connected to a drill string and to the drill bit. The rotation speed of the drill bit is periodically varied by periodic varying the rotation speed of the motor or by periodic varying the rotation speed of the drill string. Periodic bit speed rotation results in preferential cutting of material from a predetermined arc of the borehole wall which, in turn, resulting in borehole deviation. Both the drill string and the drill motor are rotated simultaneously during straight and deviated borehole drilling.

Abstract: In one aspect of the present invention a downhole tool string has a rotor secured within a bore and connected to a jack element that is substantially coaxial with the rotor. A portion of the jack element extends out of an opening formed in a working face of a drill bit located at the bottom of the drill string. The jack element is adapted to rotate independent of the drill bit when the rotor and drill bit are in operation.

Abstract: This disclosure relates in general to a method and system for controlling a drilling system for drilling a borehole in an earth formation. More specifically, but not by way of limitation, embodiments of the present invention provide systems and methods for controlling dynamic interactions between the drilling system for drilling the borehole and an inner surface of the borehole being drilled to steer the drilling system to directionally drill the borehole. In another embodiment of the present invention, data regarding the functioning of the drilling system as it drills the borehole may be sensed and interactions between the drilling system for drilling the borehole and an inner surface of the borehole may be controlled in response to the sensed data to control the drilling system as the borehole is being drilled.

Abstract: A drill bit has a body intermediate a shank and a working face and has an axis of rotation. The working face has at least one cutting element and the body has at least a portion of a jack assembly. The jack assembly has at least a portion of a shaft disposed within a cavity formed in the body of the drill bit, the shaft having a distal end extending from an opening of the cavity formed in the working face. The jack assembly also has an electric motor and/or generator.

Abstract: A drilling system, comprising: a drilling machine (10), —a drill string (26) connected at one end to the drilling machine so as to be driveable in an axial direction; and a guide (30) connected to the drilling machine such that when the drill string is driven axially by the drilling machine, it interacts with the guide so as to be directed in a predetermined radial direction; wherein the drill string is permanently engaged so as to be slideable in the guide. A method of drilling a lateral borehole from a main borehole, comprises: positioning a drilling system as claimed in any preceding claim in the main borehole; anchoring the guide in the borehole adjacent the location at which the lateral borehole is to be drilled; operating the drilling machine to drive the drill string in an axial direction; and deflecting the drill string, by means of the guide, in a radial direction into the wall of the main borehole to drill the lateral borehole.

Abstract: An orienting apparatus including at least one housing element configured to couple with a drill string; an actuator disposed inside the at least one housing element; a nozzle coupled to the actuator; a torque generator coupled to the actuator and extending axially downward through the at least one housing, wherein the torque generator is configured to rotate in a first direction as it moves downward; a mandrel coupled to the torque generator; and a stroke adjuster at least partially disposed in an upper end of the mandrel, wherein rotation in the first direction is caused by an increase in differential pressure is disclosed.

Abstract: In one aspect, a downhole assembly has a downhole tool string component with a bore adapted to accommodate drilling mud. A fluid barrier is disposed within the bore and has a cylindrical portion substantially aligned with the bore. A drive shaft is sealed within and substantially coaxial with the cylindrical portion and has a first magnet disposed on its outer surface. A turbine assembly is disposed around the cylindrical portion of the fluid barrier and has an inner diameter and outer surface. The outer surface of the turbine assembly has a plurality of turbine blades. The inner diameter of the turbine assembly has a second magnet disposed within a region defined by the turbine blades and is in magnetic communication with the first magnet of the drive shaft, wherein when the drilling mud engages the turbine blades the first and second magnets rotate the drive shaft with the turbine assembly.

Abstract: A system and method is provided for drilling a wellbore including a rotary drill bit with a bit body having a plurality of mechanical cutters to cut away formation material as the wellbore is formed; and a directed energy mechanism to direct energy into the formation such that energy from the directed energy mechanism causes fracturing of surrounding material to facilitate drilling in the direction of the directed energy.