Abstract: A device for boring a well with casing. The device is attached to a motor that has a power shaft for imparting rotational movement. The device comprises a driver operatively connected to the power shaft, with the driver containing a cylindrical body, a first bit having a first end connected to the driver so that rotational movement of the driver is imparted to the first bit, and a sleeve disposed about the power shaft, and wherein the sleeve has a radial shoulder. The device further includes casing attached to the sleeve, and wherein the casing is designed to be permanently placed within the well once the boring is completed. The device further comprises a housing disposed about the driver, a second bit attached to the housing, and a planetary gear anchored to the radial shoulder, and wherein the planetary gear is adapted for imparting rotation from the driver to the housing in a counter radial direction.

Abstract: A steering tool for use in drilling a borehole, including a tubular housing, a tool actuating device movably supported within the housing, a plurality of hydraulically actuated steering devices circumferentially spaced about the housing, and a hydraulic control system interposed between the tool actuating device and the steering devices for converting an actuating movement of the tool actuating device to independent actuation of the steering devices.

Abstract: A rotary vector gear for controlling longitudinal axis offset about a central longitudinal axis is disclosed. The device uses single rotary motion through a rotary vector gear to produce hypotrochoidic offset similar to a flower petal and is capable or ready return to zero offset. The device may be used in downhole rotary steerable oil and gas drilling tools and in computer controlled milling machines for providing controlled offset.

Abstract: An assembly for use in drilling in earth borehole using a drill string including a drill bit comprising a first downhole motor having a rotor operatively connected to said drill bit, a second downhole motor distal said first downhole motor, said second downhole motor having a rotor with a passageway therethrough and a bypass valve operatively connected to the second downhole motor, the bypass valve having a first position permitting drilling fluid to flow through said passageway and a second position wherein drilling fluid is prevented from flowing through said passageway.

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: A system for selectively orienting a bit at the end of a drillstring in a wellbore, the system, in certain aspects, having: motive apparatus for rotating a drillstring and a bit connected to an end of the drillstring; a control member manually movable to effect a change in orientation of the bit; a control system in communication with the motive apparatus and the control member for translating a signal from the control member indicative of manual movement of the control member into a command to the motive apparatus, the command commanding the motive apparatus to rotate the drillstring and the bit in correspondence to the movement of the control member.

Abstract: A downhole steering system comprises a first full gauge stabiliser 34, a bias unit 28, a universal joint 26, and a second full gauge stabiliser 22, the bias unit 28 and universal joint 26 being located between the first and second full gauge stabilisers 34, 22. Conveniently, the system further comprises a drill bit 10 and a fluid powered downhole motor 14, the motor being located, at least partially, between the drill bit 10 and the second stabiliser 22.

Abstract: A downhole steering tool is disclosed. The steering tool includes a rotatable shaft, a substantially non-rotating tool body deployed about the shaft, and a plurality of force application members deployed on the steering tool body. The steering tool further includes a bendable section deployed in the steering tool body. The bendable section is disposed to bend preferentially relative to the steering tool body under an applied bending load. The use of a steering tool body having a bendable section tends to advantageously reduce bending stresses in the steering tool body during use. Moreover, tools embodying this invention may be suitable for higher dogleg severity applications.

Abstract: A down-hole drilling assembly (12,16) and control system (120) therefor, for directional drilling including a bent housing of a bottom hole assembly (18), utilising a gearbox (102) to derive a higher speed (about 600 r.p.m.) rotational drive (104) from the drill string (10) to drive a drilling bit (20) via an electromagnetic clutch (110, 112) controlled by the control system (120) such that the clutch balances reaction torque when the orientation angle of the bent housing is correct.

Abstract: Aspects of this invention include a downhole tool having first and second members disposed to translate substantially linearly with respect to one another. A magnet is deployed on the first member and a plurality of magnetic field sensors is deployed on the second member. The magnetic field sensors are spaced in a direction substantially parallel with a direction of translation between the first and second members. The tool typically further includes a controller disposed to determine a linear position of the first and second members with respect to one another from magnetic flux measurements made at the magnetic field sensors. Exemplary position sensor embodiments of the present invention are non-contact and therefore are not typically subject to mechanical wear. Embodiments of the invention therefore tend to advantageously provide for accurate and reliable linear position measurements.

Abstract: A steerable drilling system comprises a rotary drill bit 14 secured to a housing 16, a secondary rotary drill component 22 carried by the housing and rotatable therewith, the second rotary drill component 22 having a gauge dimension greater than that of the rotary drill bit 14, and a drive arrangement operable to displace the secondary rotary drill component 22 relative to the housing 16 whilst maintaining an axis 24 of the secondary rotary drill component 22 substantially parallel to an axis 18 of the housing 16.

Abstract: The invention is an improved rotary steerable tool. The improved rotary steerable tool comprises a control tube that slides vertical within a mandrel in response to changes in drilling fluid pressure, thereby opening and closing a channel between the mandrel and a piston chamber in a rotationally isolated sleeve. With the channel open, a piston in the piston chamber is exposed to the drilling fluid. When the drilling pressure is sufficient to cause the piston to move, the piston forces a deflection pad outward. After the deflection pad engages a borehole wall, any additional increases in pressure force the opposing side of sleeve toward the opposite wall, thereby tilting the direction of any attached drill bit. An optional guide lug and alignment sleeve orient the deflection pad with respect to other components.

Abstract: Hydrostatic bearings are used for drill string stabilization and bottom hole assembly steering. The hydrostatic bearings utilize an existing mud flow as the bearing fluid. For steering, the bearings may be used between movable kick pads and the formation to reduce friction. Alternatively, differential hydrostatic bearing pressure may be utilized to steer. Multi-modal (non-linear and linear) steering may be provided by selectively applying equal and unequal hydrostatic bearing pressures. The bearings can be made more tolerant of imperfections in the formation by utilizing multiple pressure pockets.

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: The present invention relates to a rotary steerable drilling apparatus which separates the drill string from the bottom hole assembly thereby allowing the biasing means to push the bit in a given direction without having to lift the drill string along with the bottom hole assembly.

Abstract: A steerable soil penetration system having a steerable penetration head, which compacts and does not cut away the surrounding soil and which is connected to an elongate flexible tubing such that the orientation of the penetration head can be varied relative to the tubing. The elongate tubing and/or a downhole hammer or tractor pushes the penetration head through the subsurface formation. Preferably the tubing is surrounded by a narrow annulus so that buckling of the tubing is inhibited and the tubing protects the pierced hole against caving in. Optionally the tubing is circumferentially expanded after completion of the piercing process thereby increasing the width of the pierced hole and providing a permanent hole lining.

Abstract: A rotating inner member is used to drive a downhole tool housed within the hollow outer member of a dual-member drill string. The downhole tool preferably will be adapted to receive rotational energy from the inner member. In a preferred embodiment, the downhole tool is an electric generator connected to a downhole electric device. In another preferred embodiment the downhole tool is a mechanical transmission that uses the rotational energy from the inner member to drive a non-electric tool, such as a downhole hammer. This invention will increase the consistency and efficiency of downhole energy production.

Abstract: An anchoring device that includes both rotation at the leading edge of the stake which engages the ground and longitudinal thrust of the stake into the ground is disclosed. The stake portion which is driven into the ground also includes a portion which is square. This shape has been found to promote additional stability of the anchoring device. The portion of the stake which is inserted into and engages the ground includes a sleeve portion and a rotating section. The rotating section is located at the second end of the sleeve and a rotary force device is located at the first end of the sleeve. A shaft extends through the sleeve from the rotary force device to the rotating section. The sleeve portion is supported by guides mounted on the frame of the machine to be staked down. A longitudinal force imparting device is also connected to the frame. The rotating section is made up of a cutter device, an adapter section, and a tube.

Abstract: A system and method for downhole measurement for use with drill strings to reduce the borehole gap with respect to sensors carried by the drill string. In one embodiment, the sensors are mounted on a surface of the directional drilling hinged pad that comes in contact with the borehole wall. The hinged pad is pressed against the borehole wall as contact is made with the wall, thereby keeping the sensors at a minimum gap with respect to the wall. In another embodiment, the hinged pad is not used for directional drilling. Therefore the hinged pad is extended outward to the wall with the minimum necessary amount of force. Activation of the hinged pad can be initiated, for example, by flow of mud in the annulus of the string or through a user-provided command. The sensors can include resistivity, density, neutron, electromagnetic, acoustic, seismic, and NMR measurement sensors.

Abstract: A borehole may be drilled utilizing the bottom hole assembly 10, 50 with a downhole motor 14, 110, which may offset at a selected bend angle. A bend for directional drilling may be provided by a PDM, or by a RSD. A gauge section 36 secured to the pilot bit 18 has a uniform diameter bearing surface along an axial length of at least 60% of the pilot bit diameter. The bit or reamer 16 has a bit face defining the cutting diameter of the drilled hole. The axial spacing between the bend and the bit face is controlled to less than fifteen times the bit diameter. The downhole motor, pilot bit and bit may be retrieved from the well while leaving the casing string in the well.

Abstract: The drill string is fitted for drilling activity in the formation expected, including a jet nozzle equipped drill head, and a near bit kick sub. The drill string is deflected to change the progressing well bore to a preferred direction. After the change in well bore direction is accomplished by jetting, the kick sub is straightened and drilling proceeds along the new well bore center line. Ideally, the kick sub responds to direction from the surface and produces a change in drilling fluid pressure at the surface to indicate which mode, straight or deflected, is being carried out down hole.

Abstract: Drill stem elements and connections are shown with advantages such as being mechanically robust. The absence of a side access window in a sonde housing is one design feature that provides robust mechanical properties. Further advantages of sonde housings include being easy to disassemble for access to the sonde unit, or for insertion of the sonde unit. In one embodiment, a cap portion is easily secured or removed using a small allen wrench, or a hammer and a punch. The cap portion is not substantially affected or tightened by rotation of the drill stem during a drilling operation. A further advantage includes the ability to remove cap portions and pull back flexible product such as polyethylene pipe from a small exit pit.

Abstract: A drill bit for drilling a borehole with a steerable drilling system, the drill bit comprising a longitudinal axis, and a cutting profile with a leading face section blended with a curved region into a tapered gauge region having a tapered gauge profile. The tapered gauge region being tapered with respect to the longitudinal axis determined by the steerable drilling system. The cutting profile and the gauge profile lie wholly within a bit profile envelope made up of a three dimensional surface of two complimentary conical sections set at the tilt angle and separated by and blended with a rounded section which forms an outermost diameter of the bit profile envelope. The rounded section has a diameter substantially equal to a maximum allowable API diameter for the drill bit, and further has a radius of curvature substantially equal to one-half the diameter.

Abstract: A method of drilling through a masonry structure 20 includes the steps of providing a drill 10 and using the drill 10 to drill a bore 18 in the masonry structure 20. The method also includes a step of providing a reaction member in the form of a lever 28 and causing engagement of the lever 28 with the masonry structure 20 and with the drill 10 within the masonry structure 20 such that the lever 28 may provide a reaction force to assist the movement of the drill 10 through the structure 20 as it drills the bore 18.

Abstract: A technique provides a drilling system and method in which a drilling assembly is delivered downhole on coiled tubing. The drilling assembly comprises a drill bit and a motor to rotate the drill bit for drilling of a borehole. A steerable system is used to steer the drill bit, thereby enabling formation of deviated boreholes.

Abstract: A drill string is fitted at the lower end with a drill string deflecting apparatus and a drill bit. The drill string deflecting apparatus is activated to deflect the drill bit from the general center line of the drill string. Drilling proceeds to enlarge a length of larger well bore. The drill bit is lifted to allow the lower end of the drill string to move, by gravity, to the low side of the enlarged well bore. The drill string deflecting apparatus is straightened and drilling bit load is applied to drill ahead along the extended center line of the lower end of the drill string.

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: A steering tool for use in drilling a borehole, including a tubular housing, a tool actuating device movably supported within the housing, a plurality of hydraulically actuated steering devices circumferentially spaced about the housing, and a hydraulic control system interposed between the tool actuating device and the steering devices for converting an actuating movement of the tool actuating device to independent actuation of the steering devices.

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: The invention relates to a steerable soil displacement hammer for horizontal ground boring, comprising a body that can be rotated by means of a longitudinal element, and a thrust head that is mounted rotationally in relation to the body. A rotation of the body in relation to the thrust head causes the thrust head to pivot out into an asymmetrical constellation or to pivot to a symmetrical constellation. The invention also comprises a retaining feature which provides a hold in the environment and which permits a relative rotation of the body and simultaneous pivoting of the thrust head. The soil displacement hammer can be driven forwards or backwards and the retaining feature is situated in the area of the pivot axis of the thrust head.

Abstract: The disclosed orienter for use in drilling a subterranean borehole enables use of the torque provided by the drilling motor to both orient the rotating drill bit for drilling an arcuate section of the borehole and rotating the orienter housing, including a fixed bend for drilling a straight section of the borehole.

Abstract: A down-hole tool guide is disclosed for deflecting various down-hole tools having a tendency to hang or bind in uncased bore holes. The down-hole tool guide or ball guide assembly, being adaptive to the down-hole tools, extends forwardly there from and includes an eccentric rotatable ball and high-pressure jets. In cases where the guide is used to guide casing, the ball guide assembly is constructed from a drillable material thereby allowing the hole bore to be extended beyond the last set casing depth without side deviation from the original bore.

Abstract: A coiled tubing directional drilling apparatus which is operated by a mud motor and is characterized by a fixed housing and a rotary steerable bent housing or sub which is selectively rotatable with respect to the fixed housing at a fixed angle bend by a shifting mechanism, typically operated by a reversible electric motor. The motor and shifting mechanism rotate with the drive shaft and employ a lead screw in a cross-nut arrangement that selectively engages and disengages a castle lock or power take-off drive system responsive to the direction of rotation of the motor, for effecting 360-degree rotation of the bent housing with respect to the fixed housing. A sun gear and pinion gear planetary gear system facilitate rotation of the bent housing with respect to the fixed housing at a slower speed than the drive train and bit box components of the device.

Abstract: A system for drilling a substantially horizontal borehole, comprises a rotating drill string extending from a surface system to a location in the horizontal borehole, the drill string having a drill bit at a bottom end. A rotary steerable system in the drill string proximate the drill bit is adapted to direct the rotating drill string toward a desired exit point. In another aspect, a method for drilling a substantially horizontal borehole from a surface location to an offshore exit location, comprises drilling a borehole using a rotary steerable system to direct the borehole along a predetermined trajectory toward the exit location. The borehole is reamed from the surface location toward the exit location while recovering a drilling fluid at the surface location.

Abstract: For use in a wellbore containing a rotary drill string and a drill bit, the combination comprising, a rotary mandrel containing a through opening to pass drilling fluid downwardly from the interior of the drill string, and toward the bit, a non-rotary housing extending about the mandrel, a plenum or plenums in the housing in communication with the interior of the mandrel through an opening to receive fluid pressure used to actuate means associated with drilling activity in the well, and a controlled fluid gap proximate the housing, to slowly leak drilling fluid to the annulus outside the string.

Abstract: A steering head that comprises a forward pivot block and a rearward pivot block. The forward pivot block is attached to a leading edge of a casing. The rearward pivot block is attached to a trailing portion of the casing, the leading edge being separated from the trailing portion by a gap in the casing. Extending between the forward and rearward pivot blocks is a central drive shaft. The central drive shaft includes a threaded portion and is rotatable to move a drive nut away from or towards the rearward pivot block. The central drive shaft, to either side of the drive nut, is covered by a cylindrical sleeve. A second internal sleeve extends between the rearward pivot block and the drive nut to protect the threads of the drive shaft from earthen debris when the casing is being advanced or reversed to steer the forward-most casing portion during operation.

Abstract: A coupling assembly to interconnect an inner member and an outer member of a dual member drill string in torque transmitting engagement is disclosed. The coupling assembly is adapted to transmit torque input from both members to a downhole tool. In one embodiment, the coupling assembly comprises a connector sub that fixedly and non-fixedly couples both members. In another embodiment, the coupling assembly comprises a clutch mechanism to interconnect both members when the rotational speed of the outer member exceeds the rotational speed of the inner member. In another embodiment, the coupling assembly comprises a mechanism to couple both members by axial downhole movement of the inner member relative to the outer member. In another embodiment, the coupling assembly comprises a planetary gear system that interconnects both members to provide high torque to the downhole tool at relatively low output speed of the dual member drill string.

Abstract: A downhole tool comprises a joint, and a resilient member 65 which extends through the joint and provides a restoring force which tends to strengthen the joint. The joint may comprise a flex coupling 61 which allows limited articulation of the joint. First and second drill string sections 63, 64 may be interconnected by the joint, the resilient member 65 being fixed to interior surfaces of the first and second drill string sections 63, 64. A downhole tool may also comprise primary and secondary sleeves 46 that are supported relative to the mandrel 10 of the drill string. Rotational drive may be transferred from one of the sleeves to the other.

Abstract: A borehole may be drilled utilizing the bottom hole assembly 10, 50 with a downhole motor 14, which may offset at a selected bend angle. A gauge section 34 is secured to the bit 16 has a uniform diameter bearing surface along an axial length of at least 60% of the bit diameter. The axial spacing between the bend and the bit face is controlled to less than fifteen times the bit diameter. After drilling a section of the well with the BHA according to the present invention, a tubular may be inserted in the well by passing the tubular through an upper tubular, then the inserted tubular expanded while downhole to a diameter substantially equal to the expanded tubular.

Abstract: A steering tool for use in a well bore is disclosed. The tool includes at least one extendable and retractable blade deployed thereon. The blade is elastically spring biased radially inwards towards the tool such that upon removal of an actuating force, the blade retracts. In exemplary embodiments, the blade includes at least one spring-like, elastically deformable member disposed to elastically spring bias the blade. The spring-like member may include first and second elongated leg portions located on opposing sides of a sprung hairpin portion. Tools embodying this invention may be advantageous for small diameter applications.

Abstract: A method of steering a fluid drilling head in an underground borehole drilling situation is provided by rotating the flexible hose through which high pressure is provided to the drilling head and providing a biasing force on the drilling head. The hose can be rotated from a remote surface mounted situation by rotating the entire surface rig (13) in a horizontal plane about a turntable (24) causing the vertically orientated portion of the hose (11) to rotate about its longitudinal axis. The biasing force can be provided in a number of different ways but typically results from the use of an asymmetrical gauging ring on the fluid drilling head.

Abstract: A horizontal directional drilling system is used to drive operation of a guidable reamer assembly connected to a drill string. The guidable reamer assembly preferably has a cutting member with a central longitudinal axis and a support member also having a central longitudinal axis. The longitudinal axes of the cutting member and the support member are collinear when the reamer assembly is in the non-steering position and laterally displaced when in the steering position. The assembly and method of this invention provide for increased control of reaming operations and product pipe placement.

Abstract: A steering assembly includes upper and lower tubular housings connected by a universal joint. An angle cam is disposed on the end of the lower housing and projects into the upper housing. A plurality of wedge members extend axially from the upper housing and into engagement with the angle cam. Drive trains are connected to the wedge members to move the wedge members toward and away from the angle cam so as to pivot the lower housing at the universal joint and change the angle and azimuth of the lower housing with respect to the upper housing. The lower housing is connected to a bearing pack supporting a drill bit such that upon changing the angle and azimuth of the lower housing, the direction of the drilling of the drill bit is also changed. The steering assembly being connected to composite tubing having conductors in the wall thereof for conducting data and commands between the steering assembly and a processor at the surface and for providing power to the steering assembly.

Abstract: A directional borehole drilling system employs a controllable drill bit, which includes one or more conical drilling surfaces. Instrumentation located near the bit measures present position when the bit is static, and dynamic toolface when the bit is rotating. This data is processed to determine the error between the present position and a desired trajectory, and the position of one or more of the bit's leg assemblies is automatically changed as needed to make the bit bore in the direction necessary to reduce the error. The controllable drill bit preferably comprises three leg assemblies mounted about the bit's central axis, each leg having a “toed-out” axle. In response to a command signal, a lower leg translates along the bit axis to cause it to bear more of the bit weight, thus excavating more deeply over the commanded toolface sector and causing the bit to bore in a preferred direction.

Abstract: The present invention provides a method and apparatus for casing while drilling without the use of an underreamer. In one aspect, the invention provides a flexible drill collar that enables drilling of a large enough borehole for passage of the casing string therethrough.

Abstract: The drilling system includes a work string supporting a bottom hole assembly. The work string including lengths of pipe having a non-metallic portion. The work string preferably includes a composite coiled tubing having a fluid impermeable liner, multiple load carrying layers, and a wear layer. Multiple electrical conductors and data transmission conductors may be embedded in the load carrying layers for carrying current or transmitting data between the bottom hole assembly and the surface. The bottom hole assembly includes a bit, a gamma ray and inclinometer instrument package, a steerable assembly, an electronics section, a transmission, and a power section for rotating the bit. It may or may not include a propulsion system. The drilling system may be a gravity based drilling system that does include a propulsion system. Various motive means may be provided, such as gravity, to apply weight on the bit.

Abstract: A method and control system for directional drilling are described. A drill string motor is commanded to rotate at a constant speed in a forward direction and the constant speed in a reverse direction for a first duration and a second duration, respectively, for at least one oscillation cycle. The difference between an averaged absolute angle of the drill string and a target rotation angle for the drill string is maintained near zero by adjusting the length of the durations as necessary. The target rotation angle can be changed based on measurement while drilling data obtained during drilling operations. Advantageously, friction between the drill string and bore hole is reduced, leading to an increase in the drilling penetration rate.

Abstract: A data sonde for use in horizontal drilling is provided, the data sonde comprising an antenna for emitting a first modulated signal from the data sonde, the first signal comprising zero and non-zero emission components in different periods, and a receiver for receiving an intermittent second data signal during first signal zero emission periods. A method of operation of the same is also provided.

Abstract: A method of and system for directional drilling alternate between rotary drilling and sliding drilling with the bit remaining in continuous contact with the bottom of the bore hole.

Abstract: The present invention provides a hydraulically actuated downhole adjustable bent housing for use in directional drilling of bore holes and wells that allows adjustment of the housing from aligned to a bent configuration without raising or lowering the drillstring. The present invention also provides a method of directionally drilling a bore hole or a well using an downhole adjustable bent housing that can be operated without raising or lowering the drillstring.