Abstract: This disclosure relates in general to a method and a system for directionally drilling a borehole with a rotary drilling system. More specifically, but not by way of limitation, methods and system provide for controlling motion of the rotary drilling system in the borehole when a side force is applied to the drilling system to bias or focus the motion so that the drilling system directionally drills the borehole through an earth formation. In certain aspects, side cutting of a sidewall of the borehole by a drill bit under an applied side force is controlled by a geostationary element to provide for directional side cutting and, as a result, directional drilling of the borehole through the earth formation. In other aspects, a non-concentrically coupled gauge pad assembly may rotate with the drilling system and bias or focus the applied side force.

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: The invention relates to a device for generating essentially radial displacements and/or stresses of at least one mechanical part with respect to its X-X axis common with that of at least one other mechanical part functionally connected to the first one, said device comprising: (I) a frame, a swivelling ring (11) and an internal ring producing two nested ball joint connections (a) and (b) with respective centres A and B, eccentric by a distance or value ? along said X-X axis common to the two rings in a position said to be neutral, (II) one or more actuators in a barrel arrangement about the X-X axis for driving the mechanism, each actuator acting on the swivelling ring (11) via a guided push rod (3), and (III) a guide ring (4) for guiding the push rods (3) via a bidirectional planar link (e), while the swivelling rings (11, 13) are steerable by means of push rods (3) displaced by the actuators (2) and guided by the guide ring (4), and while said swivelling rings are rotatable in their respective housings

Abstract: A system and method for drilling a wellbore along a desired well path is disclosed. The system and method employed a bearing housing which may be connected into a bottom hole assembly to facilitate drilling of deviated wellbore sections. The bearing housing has an internal bore with an axis that can be positioned to form a non-zero angle with the central or longitudinal axis of the bearing housing. The internal bore is designed to rotatably receive a drill bit shaft such that a drill bit is oriented at a desired angle with respect to the bearing housing. Alternatively, the internal bore may be positioned in a sleeve which is received in the bearing housing.

Abstract: A directional drilling system and method are provided for directional drilling a borehole by continuous rotating of the drill string in combination with an arrangement of drilling motor assemblies at the lower end of the drill string to effect drilling along a curved path and a substantially straight path. A first drilling motor assembly is coupled to a drill bit and operable to rotate the drill bit to effect drilling of the borehole. A second drilling motor assembly, positioned on the drill string above the first drilling motor assembly, is operable to rotate the first drilling motor assembly in a direction opposite the direction of rotation imparted to the drill string from the surface and to the drill bit by the first drilling motor assembly.

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 bottom-hole assembly for directional drilling incorporates a torque generator with a drive shaft connected to a drill string. The torque generator generates a torque that counters a reactive torque when a drill bit of the bottom-hole assembly is driven. When the drill string is rotated at a static drive speed, a drill tool face of the bottom-hole assembly is stabilized to drill a nonlinear bore segment. When the drill string is rotated at a rotational speed other than the static drive speed the bottom-hole assembly is rotated to drill a linear bore segment.

Abstract: A wellbore is formed by using an apparatus that may include a shaft having an end portion, a drill bit body tiltable about the end portion, and at least one actuator configured to apply a tilting force to the drill bit body.

Abstract: A method and device for installing a tube of a geothermal closed loop system in the ground. A drill rod includes a hook for removably mounting the heat exchange tube for positioning the tube in the hole bored in the ground by the drill bit. The tube may be inserted into the bored hole once the drill is removed therefrom, mounted to the tube and then reinserted into the hole. Alternatively, the tube is mounted to the drill rod as the hole is being bored.

Abstract: A drill bit is provided that includes a force application device on a body of the drill bit. The force application device includes a force application member pivotally coupled to the drill bit and configured to extend from the drill bit body to apply force on a wellbore wall when the drill bit is used to drill a wellbore, and an actuator configured to actuate the force application member to apply force on a wellbore wall during drilling of the wellbore.

Abstract: A drilling system comprising a rotatable drill pipe 12 connected to a tractor unit 10, and a steerable drilling system 18, 20, 22, connected to and movable by the tractor unit 10.

Abstract: A method for drilling a wellbore comprises extending a rotatable drill string in the wellbore, where the drill string has a bottom hole assembly coupled to a bottom end thereof. A lower section of the bottom hole assembly comprising a steering apparatus is coupled to an upper section of the bottom hole assembly with a controllably adjustable clutch. A steering apparatus toolface angle is detected. The clutch is controllably adjusted to maintain the steering apparatus toolface angle within a predetermined range about a target steering apparatus toolface angle while rotating the upper section with the drill string.

Abstract: Apparatus and methods for forming an underground passageway and simultaneously laying therein a conduit or other elongate components comprises a rotary drill member coupled to a rotary and axially movable drill stem. The coupling is one which virtually automatically enables the drill stem to be coupled to and uncoupled from the drill member and comprises as one embodiment interlocking driving lugs carried by the drill stem and the drill member. The driving lugs are sandwiched between telescoped portions of the drill member and the drill stem and thereby are reinforced by such portions of the drill stem and the drill member in such manner as to preclude movement of the driving lugs in both radially inward and radially outward directions. Other couplings can be used.

Abstract: A technique facilitates control over the orientation of a bottom hole assembly. The bottom hole assembly comprises an orienting tool having a dual-spline drive which, in turn, comprises a first lead screw portion and a second lead screw portion having threads of a first pitch and a second pitch, respectively. A motor is connected to the dual-spline drive to impart rotational motion with respect to the first threads having the first pitch. A difference in pitch between the first pitch and the second pitch enables the rotational motion imparted by the motor to be converted to a slower, higher torque, output via the second lead screw portion. As a result, the orienting tool is able to provide a selective, high torque, low-speed adjustment to the drilling orientation of the bottom hole assembly.

Abstract: In one aspect of the present invention, a drill bit has an axis of rotation and drill bit body intermediate a threaded end and a working face. The drill bit body houses a jack element protruding from the drill bit body and the jack element has a plurality of inserts disposed on the indenting end.

Abstract: In certain embodiments, a steerable drilling tool is provided including a rotatable shaft extending through a housing where the shaft and the housing are separated by at least one bearing or two sets of bearings, the shaft having a first portion terminating at a first end of the shaft and a second portion terminating at a second end of the shaft. The steerable drilling tool may further include a drill bit structure operatively coupled to the first portion and a steering subsystem comprising a pair of bearings operatively coupled to the first portion. The steering subsystem may be configured to angulate the shaft by exerting force substantially through the pair of bearings. In certain embodiments, the first portion is between the first end and about one-third of the length of the shaft from the first end towards the second end.

Abstract: A method of surveying drill holes, typically for use in underground mining situations where the holes are bored using a top hammer drill rig (10), utilizes a survey tool located adjacent the drill bit (1) which is used to log position readings as the drill string is withdrawn from the hole after the drilling operation. In this manner, it is possible to log the actual hole bored by the drill string (3) in real time as the drilling operation proceeds, and show deviation from intended hole positions (5) or (6). The survey tool typically includes an inertial survey package, a power source, and a data logger with the survey package selected from the group comprising commercially known inertial known survey packages, for superior characteristics of resistance to vibration and impact. The survey tool is maintained in a sleeping mode while drilling is undertaken, and activated to provide position data as the drill string is progressively withdrawn from the actual hole path (3).

Abstract: A steerable drilling system includes a drill string carrying a bent housing, the bent housing containing or having associated therewith a drive motor arranged to drive a drive shaft angled to an axis of part of the drill string adjacent the bent housing, and an orientating motor permitting relative rotation between the drill string and the bent housing, the orientating motor driving the output shaft in a reverse direction relative to a direction of rotation of the drill string to form a curve in a borehole being formed.

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: Deep drillholes of 2 or more meters diameter down to 14-20 km and more, are with current technology extremely expensive and often not possible. Such wells are needed to run almost anywhere old nuclear/coal powerstations cheaply by geothermal steam: Water/cool steam down and hot steam up. As by-product energy is CO2-free. Steel and rock can be cut by heat of any type: conductive, radiative and heat-transmission by contact. This principle is used in the steel industry by (translated from German) “burning-cutting machines”. In addition rock can be cut by heat-induced evaporation. A ring with radii and segments that carry one to hundreds heat-generating elements moves through the rock. This way, with fairly low energy-consumption, coring is done at a high speed at almost (any) diameter. Stafette-type core- and equipment transport ensures the speed of the drilling system.

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: The present disclosure relates to a drill head having a drill head main body including a front end portion and a back end portion. The back end portion is configured to be connected to a drill rod. A steering shell is mounted over the front end portion. A drive shaft extends through the back end portion and the front end portion of the drill head main body. The drive shaft has a front end adapted for connection to a cutting unit and the drive shaft is rotatably supported within a bearing at the front end portion of the drill head main body. A steering shell driving arrangement is incorporated into the front end portion of the drill head main body for generating relative radial movement between the steering shell and the drill head main body.

Abstract: A technique is used to control the direction of a drill bit or bottom hole assembly via hydraulic steering utilizing a plurality of steering pads. A portion of hydraulic fluid, e.g. drilling fluid, is directed under pressure to a pad interface region proximate each pad. The hydraulic fluid provides additional force against a surrounding wall and/or reduces or eliminates contact between the pads and the surrounding wall.

Abstract: Embodiments described herein comprise a system and method for controlling directional drilling. The system includes a conveyance for conveying a bottom hole assembly BHA into a wellbore. The BHA may include a bent housing, a drilling tool and a motor for rotating the bent housing in the wellbore. The system further includes a conveyance rotation device for rotating the conveyance in the opposite direction of the bent housing. The direction of the bent housing may be controlled by controlling the rotational speed of the bent housing and the conveyance while drilling.

Abstract: The drill bit system may include a chassis, a head, and a first plurality of gauge pads. The chassis may be configured to be operably coupled with a first rotational motion source. The head may include a first plurality of cutters coupled with an end of the head, and the head may be rotatably coupled with chassis. The head may be configured to be operably coupled with a second rotational motion source. The first plurality of gauge pads may include a second plurality of cutters, and the first plurality of gauge pads may be fixedly coupled with the chassis.

Abstract: A method of steering a drill bit while drilling a wellbore can include periodically increasing a rotational speed of the drill bit while drilling the wellbore, with the rotational speed being increased when an axis of the drill bit is oriented in a desired azimuthal direction relative to a drill string axis. A directional drilling system can include a drill string having a bend interconnected therein, a drill bit, and a controller which selectively increases a rotational speed of the drill bit when an axis of the drill bit is oriented in a desired azimuthal direction relative to an axis of the drill string above the bend. Another method of steering a drill bit while drilling a wellbore can include interconnecting a brake in a drill string, and periodically decreasing a braking force of the brake as the drill bit is rotated.

Abstract: A drill bit is provided that in one embodiment includes a force application device on a body of a drill bit, the force application device including a floating member and a force application member configured to extend from the floating member to apply a force on a wellbore wall when the drill bit is used to drill a wellbore.

Abstract: A direction adjustment tool for a downhole drilling apparatus is disclosed. The tool has a tubular housing adapted to be incorporated into a downhole drilling apparatus, and steering blades mounted to the housing. A drive shaft transmits drive to a drill bit of a drilling apparatus, wherein the shaft defines a passage for transmitting drilling fluid to the drill bit. A first pressure chamber is defined between the housing and the shaft and communicates with the passage, wherein the steering blades are moved from retracted positions to extended positions thereof as a result of increase of fluid pressure the first pressure chamber. A pendulum member is pivotably mounted to extend in a vertical orientation when the shaft is not rotating relative to the housing, and pistons prevent movement of at least one steering blade to the extended position thereof as a result of the angle between a longitudinal axis of the shaft and the longitudinal axis of the pendulum member exceeding a predetermined amount.

Abstract: A steering tool configured for making azimuthal and non-azimuthal formation evaluation measurements is disclosed. In one embodiment a rotary steerable tool includes at least one formation evaluation sensor deployed in the steering tool housing. The steering tool may include, for example, first and second circumferentially opposed formation evaluation sensors or first, second, and third formation evaluation sensors, each of which is radially offset and circumferentially aligned with a corresponding one of the steering tool blades. The invention further includes methods for geosteering in which a rotation rate of the steering tool housing in the borehole (and therefore the rotation rate of the formation evaluation sensors) is controlled. Steering decisions may be made utilizing the formation evaluation measurements and/or derived borehole images.

Abstract: An apparatus for use in a wellbore is provided, which in one embodiment includes a drilling motor and a steering unit placed about a shaft between a lower section of a stator in the motor and a drill bit. The steering unit includes a substantially non-rotating member and a force application member on the non-rotating member configured to radially extend the force application member from the non-rotating member. In another embodiment, the steering unit may include, rotating member configured to rotate a drill bit, a steering member configured to orient the drill bit along a selected direction, a first steering device configured to orient the steering member in the wellbore, and a second steering device configured to maintain orientation of the steering member when drilling the wellbore.

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 while maintaining an axis 24 of the secondary rotary drill component 22 substantially parallel to an axis 18 of the housing 16.

Abstract: A steerable system comprises a first rotatable housing (22), a second rotatable housing (24) connected to the first rotatable housing (22) by an adjustable joint (26), a cam member (42) held against rotation, in use, and cam follower means cooperable with the cam member (42) and moveable to drive the second rotatable housing (24) for movement relative to the first rotatable housing (22) about the adjustable joint (26).

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 mechanism for adjusting the relative angular orientation of two coaxial components includes a mandrel having a cylindrical central section between upper and lower splined sections, a sleeve rotatably and slidably disposed around the mandrel's central section, and generally cylindrical upper and lower ratchet members positioned, respectively, about the mandrel's upper and lower splined sections. The ratchet members have internal grooves which receive the mandrel splines for torsional load transfer while permitting limited rotation relative to the mandrel, but their axial positions relative to the mandrel are fixed. The upper and lower ends of the sleeve have circumferentially-arrayed ratchet teeth engageable, respectively, with corresponding teeth on the upper and lower ratchet members. The central sleeve has torque-transferring external splines slidable within matching grooves on the inner surface of a cylindrical tool housing enclosing the mechanism.

Abstract: A bottom hole assembly to directionally drill a subterranean formation includes a drill bit, a stabilizer assembly located proximate to and behind the drill bit, a drilling assembly comprising a drive mechanism and a directional mechanism, and a flex housing integral with the drilling assembly.

Abstract: A housing including longitudinally extending tubular members interconnected to allow controlled relative bending thereof, during a drilling operation, a rotary drive transmitting torsion bar extending generally longitudinally within the housing to controllably bend in response to relative bending of said members, a rotary drill bit operatively connected to said torsion bar to be rotated as the bar rotates, a rotary drive operatively connected to the torsion bar to rotate the bar, means for controlling relative bending of the said members during torsion bar rotation and as a function of such rotation.

Abstract: A drilling assembly comprises a bent housing terminating in a drill bit (18), and a top section coupled to the bent section. The top section is suspended upon coiled tubing (10). The drilling assembly includes an orienter means (2-6) capable of rotating the bent housing with respect to the top section, wherein the orienter means includes an electric motor (34) situated in the bent section. The bent housing includes sensor means (30) for monitoring downhole physical variables, the sensor means being situated in the bent section. The orienter means may be an electro-mechanical motor.

Abstract: A steerable drilling system comprising a bottom hole assembly (18) including an upper section (22) and a steering section (24), a swivel (26) permitting adjustment of the orientation of an axis of the steering section (24) relative to that of the upper section (22), a downhole motor operative to drive the steering section (24) for rotation relative to the upper section (22), and a plurality of actuators (34) operable to control the orientation of the axis of the steering section (24) relative to that of the upper section (22), the (actuators 34) being mounted upon one of the steering section (24) and the upper section (22,) a high speed sliding contact being formed between the actuators (34) and the other of the steering section (24) and the upper section (22).

Abstract: A horizontal direction drilling system comprises a power pack coupled to a source of compressed air and a water reservoir and forms a mixture of compressed air, water, and oil. The horizontal direction drilling system further comprises a steerable horizontal drill. The steerable horizontal drill includes an air powered reciprocating hammer, and a drill head. The steerable horizontal drill receives the mixture to power the reciprocating hammer. The drill head includes a drill face and the mixture exits the steerable horizontal drill through the drill face.

Abstract: A directional drilling system comprises a main drill bit 24 rotatable about a main bit axis 26, a pilot drill bit 34 rotatable about a pilot bit axis 36 substantially parallel to the main bit axis 26, and adjustment means 28 for adjusting the position of the pilot bit axis 36 relative to the main bit axis 26.

Abstract: A steerable ground piercing tool includes an elongated outer housing having a lengthwise extending bore and an inner assembly at least in part disposed within the outer housing. The inner assembly includes a rotatable chisel having a longitudinally extending shaft at least in part disposed within the housing bore. The chisel has a first end defining an asymmetric tip and a second end defining a first impact surface for receiving a reciprocating action impact to drive the tool through the ground. The inner assembly further includes a conversion mechanism to selectively convert upon activation thereof at least a first portion of the reciprocating action imparted to the first impact surface into combined reciprocation and rotation of the tool.

Abstract: A downhole tool including a purely mechanical stabilizer is disclosed. The stabilizer includes a plurality of fixed blades, each of which includes at least one automatically extendable and retractable piston. In use, a balance of forces determines the radial position of each piston; a hydraulic force urging the piston outward, a spring force urging the piston inward, and external forces acting on the tool (e.g., the force of the borehole wall urging the pistons inward). The stabilizer is further configured such that a balance of forces between the pistons causes the tool to be advantageously automatically and continuously centered during rotation of the tool in the borehole. As such, the invention is suitable for use in boreholes that rapidly change size and shape.

Abstract: A downhole tool includes a slip ring assembly deployed radially between a shaft and a housing. The slip ring assembly may be configured as a stand-alone assembly and is further configured to provide a plurality of distinct electrical communication channels between the shaft and housing. These communication channels are suitable for transmitting electrical power and/or electronic data. Electrical connection is made between the housing and the slip ring assembly via a connector block that is fastened to a plurality of stator rings in the slip ring assembly. The connector block extends radially outward from the stator rings and physically engages an opening in the housing thereby rotationally coupling the stator rings to the housing.

Abstract: An exemplary device carried on a rotating drill string includes an actuator that moves force application members and an associated controller. The force application members are actuated by an eccentricity between a force application members housing and the actuator. The controller synchronizes the extension of the force application members with the rotation of the drill string such that a steering force applied by the force application members is applied in the same azimuthal direction. The controller may also control magnitude of the steering force by adjusting the eccentricity. Another exemplary device maintains a wellbore device, such as a sensor, in a substantially non-rotating condition relative to a reference frame. The device includes a sensor conveyed by a rotating wellbore tubular, a drive configured to rotate the sensor; and a processor that controls the drive to maintain the sensor in a substantially non-rotating condition relative to the reference frame.

Abstract: The present invention recites a drill bit comprising a main body having an axis about which it is rotated in use, a cutting face, a connecting means for attaching the bit to a source of rotary motion, a gauge region intermediate said cutting face and the connecting means. Additionally the gauge region comprises at least one member movable between a first position in which the gauge region is bounded by an imaginary tubular surface of constant cross-section co-axial to the axis of rotation and a second position in which a portion of the member is located radially inwards, with respect to the axis of rotation, of its position when said member is in said first position. In accordance with the present invention, the gauge region whilst said member is in said second position being bound by an imaginary three dimensional conical sectional surface; and at least one actuator.

Abstract: The invention relates to a system for the overground operation of underground sewer tools, especially of expander and pulling heads comprising a rod assembly that is rigid when pushed and a supporting device absorbing shear or tractive forces.

Abstract: A method of drilling a wellbore (1) into an earth formation is disclosed. The method comprises arranging a drill string (6) and an expandable tubular element (8) coaxially in the wellbore, the drill string having an axially extending fluid passage (30), the tubular element surrounding the drill string and having a lower end bent (12) radially outward and in axially reverse direction so as to form an expanded tubular section (10) extending around a remaining tubular section of the tubular element, said lower end defining a bending zone of the tubular element, wherein an annular space is formed between the drill string and the remaining tubular section.

Abstract: Apparatus and methods for drilling with casing. In an embodiment, methods and apparatus for deflecting casing using a diverter apparatus are disclosed. In another embodiment, the apparatus comprises a motor operating system disposed in a motor system housing, a shaft operatively connected to the motor operating system, the shaft having a passageway, and a divert assembly disposed to direct fluid flow selectively to the motor operating system and the passageway in the shaft. In another aspect, methods and apparatus for directionally drilling a casing into the formation are disclosed. Methods and apparatus for measuring the trajectory of a wellbore while directionally drilling a casing into the formation are also described.

Abstract: An apparatus for steering a drill string that includes at least one blade fixedly disposed on an exterior surface of the drill string, such that the at least one blade is rotatable about the drill string in response to fluid flow through a fluid passage in association with said at least one blade, and the at least one blade rotates independent of the drill string for imparting an asymmetrical moment to the drill string in a selected direction for orienting a drill bit attached to the drill string, thereby steering the drill string.

Abstract: Methods and apparatuses to direct a drill bit of a directional drilling assembly are disclosed. The methods and apparatuses employ the use of bi-directional actuators that are capable of displacing a hybrid steering sleeve in positive and negative directions. The bi-directional actuators are capable of greater control and precision in their actuations than traditional “engaged-disengaged” unidirectional actuators, thereby allowing for more precise directional drilling operations. The bi-directional actuators are preferably driven by drilling fluids and may optionally be shielded to lessen the erosive effects thereof.