RU2817301C2 - Rotary controlled drilling system - Google Patents

Abstract

FIELD: drilling of soil or rocks.

SUBSTANCE: invention relates to drilling technology, namely to rotary controlled drilling systems (RCS). Trajectory-controlled bottomhole assembly (BHA) comprises a drill string component including an actuator subsystem, wherein the actuator subsystem comprises an actuator with an output shaft for selective rotation of the valve disc around the axis of rotation of the BHA. Actuator subsystem further comprises a position marker on the output shaft, a position sensor near the output shaft, wherein the position sensor and the position marker interact when the position marker rotates with the output shaft to a position adjacent to the position sensor, position sensor in response transmits a signal to the actuator subsystem for use in controlling the angular orientation of the valve disc. BHA additionally comprises a deflecting subsystem passing between a drill string component and a drill bit, which receives a flow of drilling fluid under pressure through a drill string component and comprises a housing, a plurality of thrust hydraulic structures associated with the periphery of the housing, plurality of central pipes of the valve in the housing for supply of drilling mud for actuation of the corresponding one of the thrust hydraulic structures and a plurality of peripheral flow pipes in the housing for supply of drilling mud to the drilling bit. Flow tubes are located closer to periphery than central tubes of the valve. At that, according to the selected angular orientation of the valve disc relative to the valve pipes, the inlet of drilling fluid under pressure into the valve pipes is selectively provided or blocked.

EFFECT: higher efficiency of well trajectory control.

20 cl, 34 dwg

Description

Cross references to related applications

[0001] This application claims priority to U.S. Provisional Patent Application No. 62/833,792, filed April 15, 2019, and U.S. Provisional Patent Application No. 62/888,197, filed Aug. 16, 2019. The contents of each of these priority applications are incorporated herein in their entirety. as a link.

Technical field of the invention

[0002] The following relates generally to drilling technology, and more specifically to drilling rotary steerable systems (RSS).

BACKGROUND OF THE INVENTION

[0003] When drilling or coring a subterranean formation with a drill string rig, it may be desirable to obtain the ability to modify the direction of drilling to orient the wellbore in a specific desired direction to ultimately achieve the design goal. Various devices are known to provide the ability to control the trajectory of a well, which are parts of the bottom hole assembly (BHA).

[0004] For example, European patent EP0728909 in the name of Barr et al. offers drilling RUS, US patent 5,685,379 to Barr et al. proposes a method for controlling the operation of a drilling RSS, and US Patent 10,544,650 to Farley et al. offers a rotating disc valve for RUS tools.

[0005] Although various devices are known, improvements are required. For example, it may be advisable to create systems and execute in ways that are more efficient, cost effective, and better managed.

The essence of the invention

[0006] In one aspect, a well path-controlled bottom hole assembly (BHA) is provided, comprising: a drill string component including an actuator subsystem, wherein the actuator subsystem includes an actuator with an output shaft for selectively rotating a valve disk about an axis of rotation. BHA; wherein the actuator subsystem further comprises: a position marker on the output shaft; a position sensor in proximity to the output shaft, wherein the position sensor and the position marker interact, when the position marker is rotated with the output shaft to a position adjacent to the position sensor, the position sensor in response transmits a signal to the actuator subsystem for use in controlling the angular orientation of the valve disk; the BHA assembly further comprises a deflection subsystem extending between the drill string component and the drill bit, the deflection subsystem receiving a flow of pressurized drilling fluid through the drill string component and comprising: a housing; a plurality of thrust hydraulic structures associated with the periphery of the housing; a plurality of central valve tubes in the housing for moving drilling fluid to operate a corresponding one of the thrust hydraulic structures; and a plurality of peripheral flow tubes in the housing for supplying drilling fluid to the drill bit, wherein the flow tubes are located closer to the periphery than the central valve tubes, wherein, according to the selected angular orientation of the valve disc relative to the valve tubes, selectively allowing or blocking the entry of pressurized drilling fluid into the valve pipes.

[0007] In an embodiment, the deflection subsystem further comprises: a flow convergence device located downstream of the thrust structures, wherein the flow convergence device includes pipes of a convergence device for receiving and converging drilling fluid flows from the central valve tubes and peripheral flow tubes into a single outlet stream before entering the drill bit.

[0008] In an embodiment, the path-controlled BHA further comprises in the housing: a fluid manifold with an upstream surface with: a peripheral zone including flow ports, each of which is connected to a corresponding one of the peripheral flow pipes; and a central zone including valve ports, each of which is connected to a respective one of the valve central tubes, the central zone being coupled to the disk to block or subsequently allow entry of drilling fluid into the valve ports, according to the selected angular orientation of the disk relative to the upstream one. surfaces.

[0009] In an embodiment, the fluid manifold is secured to the housing.

[0010] In an embodiment, the fluid manifold includes: two flow ports; and two valve windows.

[0011] In an embodiment, each of the two peripheral flow tubes extends downstream substantially parallel to the axis of rotation of the deflection subsystem.

[0012] In an embodiment, each of the two central valve tubes extends downstream substantially parallel to the axis of rotation of the deflector subsystem.

[0013] In an embodiment, each thrust structure includes: an entrance window; at least one cylinder in fluid communication with the inlet window; a piston moving in each of the at least one cylinder in an inward and outward direction relative to the axis of rotation of the deflection subsystem; a thrust shoe mating to the piston or each piston at a periphery of the housing, wherein the thrust shoe is hinged relative to the housing and is rotatable outwardly relative to the axis of rotation as the piston or each piston is moved outwardly by hydraulic pressure to extend away from the housing.

[0014] In an embodiment, each thrust structure includes two cylinders and two corresponding pistons.

[0015] In an embodiment, the actuator subsystem is fixedly mounted and centrally mounted in the fluid pipe of the drilling component to rotate with the drilling component about the axis of rotation of the drilling component.

[0016] In an embodiment, the actuator subsystem comprises: a pipe that is dimensioned and centrally mounted in the fluid pipe to provide an annular flow zone for drilling fluid between the pipe and an internal surface of the wall of the fluid pipe, wherein the actuator is located in pipe; and an output shaft coupled to the actuator and extending axially beyond the downstream end of the pipe to mate with the disc valve component, the valve disc being part of the disc valve component.

[0017] In an embodiment, the disc valve component further includes a coupling for receiving an output shaft.

[0018] In an embodiment, the output shaft is keyed to be secured in a corresponding slot in the clutch of the disc valve component to prevent rotation relative to the clutch but allow axial sliding relative to the clutch.

[0019] In an embodiment, the actuator includes an electric motor and a gearbox.

[0020] In an embodiment, the gearbox provides a 5.8:1 reduction ratio for the electric motor.

[0021] In an embodiment, the path-controlled BHA further includes a set of axial bearings in the tube for receiving a passing output shaft to axially support the output shaft along the axis of rotation of the drilling component.

[0022] In an embodiment, the path-controlled BHA further includes a set of radial bearings in the tube for receiving a passing output shaft to radially support the output shaft along the axis of rotation of the drilling component.

[0023] In an embodiment, the actuator subsystem further comprises: a control board in a tube in communication with the actuator to control the rotation angle of the output shaft; a small-sized power supply unit for powering at least the control board and the actuator; and a sensor unit for measuring the orientation of the Earth's magnetic field and the gravity vector.

[0024] In an embodiment, the position sensor is a Hall effect sensor and the position marker is a magnet.

[0025] In an embodiment, the valve disc is generally annular and has a V-shaped groove allowing passage of drilling fluid downstream of the valve disc into a selected one of the valve central tubes.

[0026] In an embodiment, a V-shaped groove extends inward from the periphery of the valve disc to its center.

[0027] In an embodiment, the V-groove is sized to accommodate multiple valve core tubes and a valve disk to selectively orient the groove to allow drilling fluid to enter only one valve core tube at a time.

[0028] In an embodiment, the V-groove is sized to accommodate a plurality of valve core tubes and a valve disk to selectively orient the groove to prevent drilling fluid from entering any of the valve core tubes.

[0029] In an embodiment, the path-controlled BHA further includes a cylindrical nipple protruding from a downstream surface of the valve disc.

[0030] In an embodiment, the inward facing side of each thrust shoe is configured to symmetrically distribute the force transmitted to the corresponding one or more pistons along the piston stroke axis over the entire piston stroke.

[0031] In an embodiment, the inward facing side of each thrust shoe is concave.

[0032] In an embodiment, the inward facing side of each thrust shoe is configured, when the BHA 50 is centered in the well, to transmit force to a corresponding one or more pistons in alignment with the respective axes of the pistons' stroke.

[0033] In another aspect, a deflection subsystem is provided for a path-controlled bottom hole assembly (BHA), comprising: a housing having an axis of rotation; a plurality of flow pipes in the housing for supplying drilling fluid received at the upstream end of the housing to the downstream end of the housing; a plurality of thrust hydraulic structures, each extending from inside the housing to the periphery of the housing; a plurality of valve pipes in the housing, each for supplying drilling fluid to a corresponding one of the thrust hydraulic structures, wherein the flow pipes are not located between the thrust hydraulic structures and the axis of rotation.

[0034] In an embodiment, the deflection subsystem further comprises: a convergence device located downstream of the thrust structures, wherein the convergence device includes pipes of a convergence device for receiving and converging drilling fluid flows from valve pipes and flow pipes into one outlet stream before exiting the diverter subsystem.

[0035] In an embodiment, the deflection subsystem further comprises in the housing: a fluid manifold, with an upstream surface with: a peripheral zone including flow ports, each of which is associated with a corresponding one of the flow pipes; and a central zone including valve ports, each of which is connected to a respective one of the valve conduits, the central zone being sized to interface with the actuator assembly to block or subsequently allow entry of drilling fluid into the valve ports.

[0036] In an embodiment, the fluid manifold is secured to the housing.

[0037] In an embodiment, the fluid manifold includes: two flow ports and two valve ports.

[0038] In an embodiment, each of the two flow tubes extends downstream substantially parallel to the axis of rotation of the housing.

[0039] In an embodiment, each of the two valve tubes extends downstream substantially parallel to the axis of rotation of the housing.

[0040] In an embodiment, each thrust structure includes: an entrance window; at least one cylinder in fluid communication with the inlet window; a piston moving in each of the at least one cylinder in an inward and outward direction relative to the axis of rotation of the deflection subsystem; a thrust shoe mating to the piston or each piston at a periphery of the housing, the thrust shoe being hinged relative to the housing and being rotatable outwardly relative to the axis of rotation as the piston or each piston is moved outwardly by hydraulic pressure to be retractable from the housing.

[0041] In an embodiment, each thrust structure includes two cylinders and two corresponding pistons.

[0042] In an embodiment, the inward facing side of each thrust shoe is configured to symmetrically distribute the force transmitted to the corresponding one or more pistons along the piston stroke axis over the entire piston stroke.

[0043] In an embodiment, the inward facing side of each thrust shoe is concave.

[0044] In an embodiment, the inward facing side of each thrust shoe is configured, when the BHA 50 is centered in the well, to transmit force to a corresponding one or more pistons in alignment with the respective axes of the piston strokes.

[0045] In another aspect, an actuator subsystem is provided for assembling a bottom hole string (BHA), the actuator subsystem comprising: an actuator mounted to the drilling component and having an output shaft for selectively rotating a valve disk about an axis of rotation of the BHA; position marker on the output shaft; a position sensor in the vicinity of the output shaft, wherein the position sensor and the position marker interact, when the position marker is rotated with the output shaft to a position adjacent the position sensor, the position sensor in response transmits a signal to the actuator subsystem for use in controlling the angular orientation of the valve disk.

[0046] In an embodiment, the actuator subsystem is sized to be fixedly mounted and centrally mounted in the drilling component fluid pipe to rotate with the drilling component about the drilling component's axis of rotation.

[0047] In an embodiment, the actuator subsystem comprises: a pipe that is dimensioned and centrally mounted in the fluid pipe to provide an annular flow zone for drilling fluid between the pipe and an internal surface of the wall of the fluid pipe, wherein the actuator is located in pipe; and an output shaft coupled to the actuator and extending axially beyond the downstream end of the pipe to mate with the disc valve component, the valve disc being part of the disc valve component.

[0048] In an embodiment, the disc valve component further includes a coupling for receiving an output shaft.

[0049] In an embodiment, the output shaft is keyed to be secured in a corresponding slot in the clutch of the disc valve component to prevent rotation relative to the clutch but allow axial sliding relative to the clutch.

[0050] In an embodiment, the actuator includes an electric motor and a gearbox.

[0051] In an embodiment, the gearbox provides a 5.8:1 reduction ratio for the electric motor.

[0052] In an embodiment, the actuator subsystem further includes a set of axial bearings in the tube for receiving a passing output shaft to axially support the output shaft along the axis of rotation of the drilling component.

[0053] In an embodiment, the actuator subsystem further includes a set of radial bearings in the tube for receiving a passing output shaft to radially support the output shaft along the axis of rotation of the drilling component.

[0054] In an embodiment, the actuator subsystem further comprises: a control board in the conduit and in communication with the actuator to control the rotation angle of the output shaft; a small-sized power supply unit for powering at least the control board and the actuator; and a sensor unit for measuring the orientation of the Earth's magnetic field and the gravity vector.

[0055] In an embodiment, the position sensor is a Hall effect sensor and the position marker is a magnet.

[0056] In an embodiment, the valve disc is generally annular and has a V-shaped groove allowing drilling fluid to pass downstream of the valve disc into a selected one of a plurality of valve tubes in a downstream deflector subsystem with which the actuator subsystem can dock.

[0057] In an embodiment, a V-shaped groove extends inward from the periphery of the valve disk to its center.

[0058] In an embodiment, the V-groove is sized to accommodate multiple valve tubes in the downstream deflector subsystem and selective orientation of the valve disc to allow drilling fluid to enter only one valve tube of the downstream deflector subsystem at a time.

[0059] In an embodiment, the V-groove is sized to accommodate multiple valve tubes in the downstream deflector subsystem and to selectively orient the valve disk to prevent drilling fluid from entering any of the central valve tubes of the downstream deflector subsystem.

[0060] In an embodiment, the actuator subsystem further includes a cylindrical nipple protruding from a downstream surface of the valve disk.

[0061] Other aspects and embodiments will become apparent from the description below.

Brief description of drawings

[0062] Embodiments of the invention are described below with reference to the accompanying drawings, which show the following.

[0063] In FIG. 1 is a side view of a bottom hole assembly of an embodiment comprising a drill collar, a diverter subsystem, and a drill bit.

[0064] In FIG. 2 in a cross-section of the bottom hole assembly of FIG. 1, along the line N-N in Fig. 1 shows an actuator subsystem housed in a drill collar of an embodiment.

[0065] In FIG. 3 is an enlarged side view of the actuator subsystem of FIG. 2 separately.

[0066] In FIG. 4 shows a cross-section of the actuator subsystem of FIG. 3, along line B-B in FIG. 3.

[0067] In FIG. 5 is an enlarged view of a downstream portion of the actuator subsystem of FIG. 4.

[0068] In FIG. 6 is an isometric view of the actuator subsystem of FIG. 3.

[0069] In FIG. 7 is an enlarged isometric view of the downstream portion of the actuator subsystem of FIG. 6;

[0070] In FIG. 8 is a side view of the deflection subsystem of FIG. 1 separately.

[0071] In FIG. 9 shows a cross-section of the deflection subsystem of FIG. 8, along line C-C in FIG. 8.

[0072] In FIG. 10A shows a cross-section of the deflection subsystem of FIG. 8 along line D-D in FIG. 9;

[0073] In FIG. 10B shows a cross-section of a bottom hole assembly identical to that shown in FIG. 2, but centered in the borehole in the rock.

[0074] In FIG. 10C is a cross-sectional view of the deflection subsystem of the bottom hole assembly centered in the wellbore as in FIG. 10B, along line B-B in FIG. 10B.

[0075] In FIG. 11 is an upstream end view of the deflection subsystem of FIG. 8.

[0076] In FIG. 12 is an end view of the upstream fluid manifold of the deflection subsystem of FIG. 8 embodiment.

[0077] In FIG. 13 is an isometric view of the fluid manifold of FIG. 12, with the internal fluid pipes shown in dotted lines.

[0078] In FIG. 14 is an upstream end view of a fluid manifold for a deflection subsystem of an alternative embodiment.

[0079] In FIG. 15 is an isometric view of the fluid manifold of FIG. 14, with internal fluid pipes shown in dotted lines;

[0080] In FIG. 16 is a side view of the deflection subsystem having the fluid manifold of FIG. 14.

[0081] In FIG. 17 shows a cross-section of the deflection subsystem of FIG. 16, along line G-G in FIG. 16.

[0082] In FIG. 18 shows a cross-section of the deflection subsystem of FIG. 16, along line H-H in FIG. 17.

[0083] In FIG. 19 is an upstream end view of the deflection subsystem of FIG. 16.

[0084] In FIG. 20 is a cross-sectional view of the deflection subsystem of FIG. 16, along line L-L in FIG. 19.

[0085] In FIG. 21 shows another side view of the deflection subsystem with the fluid manifold of FIG. 14, with one of the thrust structures slightly extended to control the trajectory of the embodiment.

[0086] In FIG. 22 shows a cross-section of the deflection subsystem of FIG. 21, along line G-G in FIG. 21, and the deflection subsystem is shown, which also includes a device that brings the flows to one point, located downstream of the thrust structures.

[0087] In FIG. 23 shows a cross-section of the deflection subsystem of FIG. 21, along line H-H in FIG. 22.

[0088] In FIG. 24 is an upstream end view of the deflection subsystem of FIG. 21.

[0089] In FIG. 25 is a cross-sectional view of the deflection subsystem of FIG. 21 along the line R-R in FIG. 24.

[0090] In FIG. 26 is a view from the upstream end that brings the flows to one point of the device of FIG. 22 individual embodiments.

[0091] In FIG. Fig. 27 shows a cross-section of the device of Fig. that brings flows to one point. 22 along line P-P in FIG. 26.

[0092] In FIG. 28 shows an isometric view from the upstream side of the device of FIG. 22.

[0093] In FIG. 29 shows an isometric view from the upstream side of the device of FIG. 22 with the internal fluid pipes shown in dotted lines.

[0094] In FIG. 30 is a cross-sectional view of a bottom hole assembly showing the actuator subsystem of an alternative embodiment housed in a drill collar.

[0095] In FIG. 31 is an enlarged view of a downstream portion of the actuator subsystem of FIG. thirty.

[0096] In FIG. 32 is an enlarged isometric view of portions of the downstream portion of the actuator subsystem of FIG. thirty.

Detailed description

[0097] In FIG. 1 shows a side view of the bottom hole assembly (BHA) 50 for a drilling RSS embodiment. In this embodiment, the BHA 50 includes a drill collar 100, a deflector subsystem 200, and a drill bit 300 connected in series from the upstream end to the downstream end of the BHA 50 (from left to right in FIG. 1). The drill collar 100 may in turn be coupled at its upstream end to an upstream component (not shown) of the drill string to connect the BHA 50 to the rest of the drilling system.

[0097] During operation of the drilling system, the BHA 50 rotates generally about a central longitudinal axis in the well being drilled, along with the rest of the drill string to which it is connected. In addition, the BHA 50 receives at its upstream end a flow of pressurized drilling or mud fluid pumped through the drill string. As described below, the BHA 50 is fed with drilling fluid downstream before exiting the BHA 50 through the drill bit 300. This drilling fluid enters the well under pressure to assist in removing cuttings from the well.

[0099] In this embodiment, described below, the deflector subsystem 200 can be controlled to selectively direct some of the flow of drilling fluid under pressure by the deflector subsystem 200 to control the path of movement. This directional flow can be used to actuate multiple thrust structures positioned around the periphery of the deflector subsystem 200. Actuating the thrust structure at a particular rotation angle of the drill string causes the thrust structure to be pushed outward and against the borehole wall at such an angle of rotation as to direct the trajectory. movement of the BHA 50 in the opposite direction.

[00100] In FIG. 2 shows a cross-section of the BHA 50, along the line N-N in FIG. 1. As shown, drill collar 100 includes a body 102 having a first threaded portion 104 at its upstream end. The first threaded portion 104 is sized (ie, sized and shaped) to screw the drill collar 100 to an upstream drill string component (not shown). Housing 102 also has a second threaded portion 106 at its downstream end. The second threaded portion 106 is sized to screw the drill collar 100 to the first threaded portion 204 of the deflector subsystem 200.

[00101] The fluid pipe 108 extends centrally through the body 102 of the drill collar 100 from the upstream end through to the downstream end. Fluid pipe 108 supplies drilling fluid to diverter subsystem 200 and drill bit 300. In this embodiment, actuator subsystem 150 is mounted fixedly at the center of fluid pipe 108 to rotate with drill collar 100 about its central axis during drilling operation. columns. The actuator subsystem 150 extends partially beyond the downstream end of the drill collar 100 to interface with components of the diverter subsystem 200 and to control the trajectory as described below.

[00102] The actuator subsystem 150 is sized and mounted in the fluid pipe 108, leaving a substantial annular flow zone 110 between the periphery of the subsystem and the inner wall surface of the fluid pipe 108. The annular flow zone 110 allows drilling fluid to continue through from the upstream end of the drill collar 100 and exit out of the downstream end.

[00103] In FIG. 3 is an enlarged side view of the actuator subsystem 150 in isolation, and FIG. 4 shows a cross-section of actuator subsystem 150 along line B-B in FIG. 3. In this embodiment, the actuator subsystem 150 operates as a rotary valve system. In addition, the actuator subsystem 150 is based on a “probe shape”. For example, its components (small power supply such as batteries, actuator, control board, sensors, as described below) are housed in a probe-like tube 152 with standard measurement-while-drilling (MWD) unit dimensions. In this embodiment, pipe 152 is cylindrical and has an outer diameter of 1 7/8 (one and seven eighths) inches (47 mm). Protruding from the downstream end of pipe 152 is a rotating output shaft 154 that is keyed to be secured in a corresponding slot in the clutch of disc valve component 156. This ensures that the disc valve component 156 rotates when the output shaft 154 rotates without slipping. However, the output shaft 154 and the disc valve component 156 are axially separated to provide a small amount of axial slip relative to each other. This axial “game” is only minor. Axial play is useful for accommodating potential tolerance overlap in either the “too short” direction or the “too long” direction. It is beneficial to have the disc valve component 156 seated on the upstream surface 222 without necessarily pressing into it, which may otherwise happen if tolerances during component machining cause a sequence of small components to extend too far, or not far enough in comparison. with a value useful for reliable long-term operation. That is, it is preferable, from the standpoint of both wear and power consumption, that the disc valve component 156 can rotate relative to the upstream surface 222 of the output shaft 154 with as little friction as possible between the upstream surface 222 and the disc valve component 156, and also worked to effectively lock and unlock the valve windows as described.

[00104] As described below, the actuator 164 (in this embodiment, the motor and gear assembly) in the pipe 152 can rotate the output shaft 154 relative to the pipe 152. The shaft, in turn, rotates the disc valve component 156 relative to the pipe 152. Thus, the component The disc valve component 156 can be rotated relative to the components of the deflector subsystem 200 to which the disc valve component 156 is to be mated.

[00105] As shown in FIG. 4, a small power supply unit, in this embodiment, battery pack unit 155, provides electrical power to motor/gearbox 164, as well as sensor unit 160 and control board 162. In this embodiment, the battery pack unit 155 has one battery pack including eight (8) lithium primary current sources, DD, connected in series. Since each current source has a voltage of 3.6 V, the nominal voltage of the set is 28.8 V. In embodiments, the battery pack unit 155 contains two sets of batteries providing approximately 100 hours of continuous downhole operation. The battery pack unit 155 may have more battery packs as required at the site within the dimensions of the actuator subsystem 150.

[00106] The sensor unit 160 includes, in this embodiment, three (3) orthogonal magnetometers for measuring the orientation of the Earth's magnetic field relative to the sensor unit 160 and three (3) orthogonal accelerometers for measuring the gravity vector relative to the sensor unit 160. The control board 162 supports and provides power to an information processing structure, such as a microprocessor, to receive data signals from said sensor assembly components. The information processing framework processes the data signals and performs predictive filtering to smooth the incoming signals. The information processing structure is also configured to accommodate the lag time that occurs when receiving signals and the processing time required when the tool is rotated at several hundred revolutions per minute (rpm). In general, the information processing structure is configured to obtain a lateral inclination angle vector representing the direction from the measured orientation of the BHA 50 to the orientation of the BHA 50 toward the design target. When the side tilt angle vector is determined, the control board 162 may activate the motor/gearbox 164, respectively, to rotate the disc valve component 156. The rotation of the disc valve component 156 is controlled such that its rotational speed brings it to a position relative to the deflector subsystem 200 corresponding to the side tilt angle to the design target minus the measured side tilt angle. It will be understood that the information processing structure on the control board 162 is configured to take into account the lag time between the reception of measurements at the sensor unit 160 and the response actuation of the motor/gearbox 164.

[00107] In FIG. 5 is an enlarged view of a downstream portion of the actuator subsystem 150. In this embodiment, motor/gearbox 164 is a single unit that includes a motor with a gearbox providing a reduction ratio of 5.8:1. The output shaft 166 of the motor/gearbox 164 is connected by a coupling 168 to the output shaft 154. The output shaft 154 extends from the coupling 168 all the way to the disc valve component 156. In this embodiment, the output shaft 154 passes through both a set 172 of axial load-bearing thrust bearings resisting axial movement of the output shaft 154 and a set 174 of radial bearings resisting radial movement of the output shaft 154. A seal 175 is mounted on the downstream end of the pipe 152. , preventing the entry of drilling fluid or other material.

[00108] The position sensor 176 is fixed in the pipe 152 near the coupling 168, and the corresponding position indicator 178 is fixed at a point of the coupling 168 corresponding to the axial location of the position sensor 176. The position sensor 176 and the position indicator 178 interact to provide the position sensor 176 with information about the rotation of the position indicator 178 to a position near the position sensor 176, so that the position indicator 178 can transmit a signal to the control board 162 whenever the position indicator 178 is located near the position sensor 176. In this embodiment, the position sensor 176 is a Hall sensor, and the position indicator 178 is a magnet. When the output shaft 154 is rotated such that the position indicator 178 rotates to become adjacent to the position sensor 176, the position sensor 176 quickly transmits an electrical signal to the control board 162. The control board 162 then receives the angular position and speed of the output shaft 154 relative to the drill collar 100 as the output shaft 154 rotates. The control board 162 can therefore, in turn, receive angular position data of the disc valve component 156 relative to the deflector subsystem 200. Given the angular position data of the disc valve component 156 relative to the deflector subsystem 200, the control board 162 adapts or maintains the angular position. The control board 162 does this by instructing the motor/gearbox 164 to accelerate, decelerate, or stop the rotation of the output shaft 166 to control the path of the BHA 50.

[00109] In this embodiment, position sensor 176 includes circuitry for filtering (such as Kalman filtering) to obtain reliable shaft position data even under downhole vibration conditions.

[00110] In an embodiment, the control board 162 is configured to selectively operate using a duty cycle to implement the kick frequency of the deflection subsystem 200. For example, the duty cycle may be set to control the deflection subsystem 200 to create a path deviation within one minute, and then no trajectory deviation for one minute, and then trajectory deviation for one minute. More specifically, 50% duty cycle. The control board 162 may be configured to control the operation of the deflection subsystem 200 over various other operating cycles.

[00111] In an embodiment, the control board 162 may receive commands from the surface well equipment and execute them to change the operation of the BHA 50. Since wired communication to the surface through the BHA 50 may not be practical, other means of communication may be employed. For example, mud pumps can be controlled to modulate the flow of drilling fluid, or the speed of rotation of the drill string can be modulated to provide a signal downhole. The actuator subsystem 150 may be provided with components to detect changes in vibration levels or rotational speeds to detect signal transmission and accordingly respond with control signals to the motor 164. Data rates for such downhole communication configurations are typically less than 0.3 bps . Other techniques can be used to transmit signals to the bottom.

[00112] In an embodiment, signals can be transmitted from the actuator subsystem 150 to the surface during operation using a drilling fluid column pressure pulse generator component or using electromagnetic (EM) telemetry (where electrical signals are transmitted through the rock environment of the formation itself). Such a system may employ a mud pulse transmitter or EM transmitter directly on the BHA 50. Alternatively, a system with a short distance transmission channel may be employed.

[00113] In FIG. 6 is an isometric view of actuator subsystem 150, and FIG. 7 is an enlarged isometric view of a downstream portion of the actuator subsystem 150. As shown in FIG. 7, disc valve component 156 includes a disc 157. The disc 157, in this embodiment, is generally annular and has a V-shaped groove 159 extending inwardly from one portion of its periphery part way to its center. The V-groove 159 in this embodiment is sized (ie, the groove has an arc angle and an inward extension) to ensure that the V-groove 159 aligns with only one underlying valve port at a time. That is, to unlock only one valve window while blocking the other valve window(s). This allows drilling fluid to pass downstream through V-groove 159 and only into the valve port aligned with V-groove 159. With this orientation of disk 157, the remainder of disk 157 essentially blocks any other underlying valve ports from receiving drilling fluid. .

[00114] Additionally, in this embodiment, the V-groove 159 is sized to ensure that the V-groove 159 is not selectively aligned with any of the underlying valve ports. That is, such an orientation that the rest of the disk 157 blocks all of the valve windows. In this way, it is possible to prevent drilling fluid from entering any of the thrust structures by controlling the orientation of the disk 157 and, in particular, the V-groove 159. This “neutral” position may be desired when trajectory control is not required (known colloquially as as “neutral position”). It may be noted that a neutral position of some kind can be achieved another way by continuing to drive all thrust structures in a pseudo-random mode or other automatic counteraction as the drill string rotates, causing no effective path control. However, when the thrust structures continue to be driven in this manner even when trajectory control is not required, energy consumption continues, as well as wear and tear on the thrust structures and other components; the thrust shoes continue to press against the borehole wall. However, by making the valve structure described herein configured such that it can be oriented to unlock only one valve port at a time and, additionally, can alternatively be oriented to block all valve ports for a period of time such that none of the thrust structures are not actuated, wear and tear on at least the components of the thrust structure, as well as power consumption, can be reduced compared to other approaches to obtain a neutral position.

[00115] It will be appreciated that the angle/size of the V-groove 159 in the disk 157 can be selected depending on the number of valve ports, their sizes, and the spacing between the valve ports.

[00116] A V-shaped groove extends inwardly in disk 157 from the periphery, in contrast (for example), an aperture (such as an annular hole) passing through disk 157 spaced from the periphery provides disk 157 with a circumference extending only to points where valve ports reach from the center of the upstream surface 222. It is clear that little interference with the flow ports of the disk 157 is desirable so that the flow ports are not obstructed as much as possible by the disc 157. Although an alternative disc with a through hole spaced inward from its periphery for alignment with the underlying valve port may be functional, such an alternate disk must have a radius greater than the distance that the valve port extends from the center of the upstream surface 222. That is, such an alternative disk to accommodate a complete through hole that is aligned with the underlying valve window must have a radius greater than that necessary to simply close the valve windows. Since such an alternative disk must have a radius larger than necessary, the flow windows must be located further from the axis of rotation of the deflection subsystem 200, in which case they cannot be even partially blocked by the alternative disk. Thus, by providing a V-shaped groove 159 extending inward from the periphery of disk 157 as described herein, a sufficiently large opening can be created to allow passage of drilling fluid into selected valve ports without requiring a larger than necessary radius of disk 157 and the distance from the flow windows to the axis of rotation of the subsystem.

[00117] In this embodiment, a short cylindrical nipple 158 extends from the center of the downstream surface of the disc 157 and must contact a corresponding component of the deflector subsystem 200 to allow the disc valve component 156 to rotate relative to the deflector subsystem 200 with very little added friction. This reliably enables the disc valve component 156 to be rotated by the battery-powered electric motor 164 with a small amount of battery-powered drive power.

[00118] In FIG. 8 shows a side view of the deflection subsystem 200 in isolation, and FIG. 9 shows a cross-section of the deflection subsystem 200 along line C-C in FIG. 8. In this embodiment, the deflection subsystem 200 includes a housing 202 including a fluid manifold 220 located immediately downstream of the first threaded portion 204. The fluid manifold 220 has an upstream surface 222 facing the flow of drilling fluid, exiting the drill collar 100.

[00119] In FIG. 12 is an upstream end view of the fluid manifold 220 of an embodiment, and FIG. 13 is an isometric view of the fluid manifold of FIG. 12 with the internal fluid pipes shown in dotted lines.

[00120] The upstream surface 222 has a central zone 224 (shown as a line of dots in FIG. 12) and a peripheral zone 225 extending from the central zone to the periphery of the upstream surface 222. In this embodiment, three (3) valve windows 226A, 226B and 226C. The valve windows 226A, 226B and 226C are flush with and open to the upstream surface 222. Each of the valve ports 226A, 226B and 226C is in fluid communication with a corresponding valve pipe 240A, 240B and 240C extending downstream from the upstream surface 222 of the fluid manifold 220.

[00121] As described below, when drill collar 100 is screwed onto deflector subsystem 200, disk 157 extending from actuator subsystem 150 protrudes toward and ultimately contacts upstream surface 222. Disc 157 is therefore centered relative to central region 224 of upstream surface 222 and valve ports 226A, 226B and 226C. A cylindrical pin 158 extending from the downstream surface of the disk 157 contacts a portion of the central region 224 of the upstream surface 222 between the valve portions 226A, 226B, and 226C. In embodiments, a short cylindrical cup (not shown) having walls parallel to the axis of rotation of the BHA 50 extends immediately slightly downstream of the upstream surface 222. This is provided to receive a short cylindrical nipple 158 to assist in maintaining the disk 157 in a central position. facing the central region 224. In such embodiments, the short cylindrical cup is preferably sized to interfere slightly with the rotation of the short cylindrical nipple 158. For example, the cup preferably has a depth only slightly less than the corresponding length of the nipple 158 such that the downstream surface disk 157 does not actually contact the upstream surface 222 when rotated relative to it, but is very slightly offset from it so as to maintain little friction between the two components. In this embodiment, nipple 158 has a diameter of between 1/16 and 1/8 inch (1.6 and 3.2 mm) with a length of about 1/32 inch (0.8 mm), and the short cylindrical cup, in turn, has a diameter about 10/1,000 inch (0.3 mm) larger than nipple 158 with a depth about 10/1,000 inch (0.3 mm) less than the length of nipple 158. Alternatives are possible.

[00122] By controlling the angular position of disk 157 relative to center zone 224, disk 157 does or does not block valve windows 226A, 226B, or 226C. This, in turn, allows the actuator subsystem 150 to control whether pressurized drilling fluid received in the drill collar 100 can enter any of the valve ports 226A, 226B, or 226C.

[00123] In the peripheral zone 225 of the upstream surface 222, three (3) flow ports 228A, 228B and 228C are located. Flow ports 228A, 228B, and 228C are flush with and open to the upstream surface 222. In this embodiment, each of the flow ports 228A, 228B and 228C is in fluid communication with a corresponding flow pipe 229A, 229B and 229C extending downstream of the upstream surface 222 of the fluid manifold 220. The disk 157 is sized to interface only with the central zone 224 of the upstream surface 222 and not substantially with the peripheral zone 225 of the upstream surface 222. The flow ports 228A, 228B and 228C remain substantially not blocked by any valve structure. As a result, the main flow of drilling fluid can continue downstream to the drill bit 300 without being significantly affected as it would otherwise be by valve operation.

[00124] In this embodiment, as the valve conduits 240A 240B and 240C extend downstream from the upstream surface 222 to their respective thrust structures, each also extends somewhat outward toward the periphery of the fluid manifold 220 and away from the central axis of the manifold 220 fluid. In addition, as the flow tubes 229A, 229B and 229C pass downstream of the upstream surface 222, they converge. Specifically, flow pipes 229A, 229B, and 229C extend somewhat inward toward the central axis of the fluid manifold 220 to converge into a single, central outlet port 230. In this way, three main mud flows are formed when the incoming drilling mud reaches the upstream surfaces 222 of the fluid manifold 220 are reconnected downstream from the upstream surface 222 before entering the drill bit 300.

[00125] Returning to FIG. 9, valve pipe 240A delivers pressurized drilling fluid to the corresponding thrust structure when the valve window 226A is not blocked by disk 157. Valve pipe 240A extends past the downstream surface of the fluid manifold 220 a short distance for insertion into the corresponding inlet pipe 242A of the corresponding thrust structure. to provide a connection between pipes 240A, 242A. The throttling stage 208 immediately downstream of the fluid manifold 220 creates a central back pressure, which is useful in providing the drilling fluid with sufficient hydraulic pressure to flow along the valve pipe 240A.

[00126] Although embodiments of the thrust structure are described herein with, respectively, two cylinders and pistons each, actual embodiments of the thrust structure may have three or more cylinders/pistons per thrust structure. It should be noted that although two cylinders/pistons are shown in the present embodiments for better understanding, a thrust design with fewer or more cylinders/pistons may operate generally the same as described herein.

[00127] In this embodiment, the thrust structure corresponding to the valve pipe 240A includes an inlet pipe 242A and two cylinders 250AA and 250AB in fluid communication with the valve pipe 240A through the inlet pipe 242A. The thrust structure also includes pistons 255AA and 255AB sliding in a respective one of two cylinders 250AA and 250AB. In turn, pistons 255AA and 255AB mate with the underside of one thrust shoe 260A. The thrust shoe 260A is pivotally attached to the outer portion of the housing 202 of the deflection subsystem 200 at its periphery and is rotatable outwardly about the axis of rotation as the piston or each piston 255AA and 255AB moves outwardly under hydraulic pressure. Thus, the thrust shoe 260A extends from the periphery of the housing 202 under this condition.

[00128] When drilling fluid is allowed to enter valve window 226A by disk 157, inlet pipe 242A supplies drilling fluid under pressure to cylinders 250AA and 250AB. The outlet pipe 252A extends downstream of the thrust structure and includes a throttle. The choke, in this embodiment made of carbide, reduces the outlet pipe 252A to a diameter smaller than that of the inlet pipe 242A to provide the outlet pipe 252A with an effective opening with a cross-sectional area that is approximately 60% of the cross-sectional area of the inlet pipe 242A. This constriction increases back pressure so that the drilling fluid is pushed into the thrust structure rather than simply bypassing it. The drilling fluid entering the cylinders 250AA and 250AB in turn causes the pistons 255AA and 255AB to slide outward (upward, as seen in FIG. 9) while together pushing the thrust shoe 260A outward and against the borehole wall. The thrust shoe 260A thus contacts the borehole wall while pushing the BHA 50 in the opposite direction. When the valve window 226A is then locked, the fluid pressure in the respective cylinders 250AA, 250AB drops and the thrust shoe 260A moves back to its neutral position against the body 202. This is simple because the force acting on the outside of the thrust shoe 260A, which transmitted by the wall at a given point, there is not enough counteracting force acting on the underside of the thrust shoe 260A through the pistons 255AA, 255AB. The drilling fluid passes further downstream from the thrust structure through the outlet pipe 252A and its choke. The drilling fluid passing downstream of the thrust structure, outlet pipe 252A, then converges with the main pressurized fluid stream near the outlet at the downstream end of the deflector subsystem 200.

[00129] A second threaded portion 206 at the downstream end of the deflector subsystem 200 may be screwed to a corresponding threaded portion of the drill bit 300 to deliver pressurized fluid exiting the deflector subsystem 200 into the drill bit 300.

[00130] In FIG. 10A shows a cross-section of the deflection subsystem 200 along line D-D in FIG. 9. In FIG. 9 shows only one outlet pipe 252A (including the orifice) and associated thrust structure. At the same time, in the cross-sectional view of the end of Fig. 10A shows the relationship between the other two (2) thrust structures along with the corresponding outlet pipes 252B and 252C and their respective flow restrictors.

[00130] Specifically, in FIG. 10A shows a portion of the thrust structure comprising an outlet pipe 252B (with associated throttle), a cylinder 250BB and a piston 255BB, structurally the same as the cylinder 250AB and piston 255AB, driving the thrust shoe 260B. Likewise, another thrust structure includes an outlet pipe 252C (with associated throttle), a cylinder 250CB and a piston 255CB, structurally the same as the cylinder 250AB and piston 255AB, driving the thrust shoe 260C. It will be understood that, although not shown in the figures, cylinders and pistons that are structurally the same as the cylinder 250AA and piston 255AA of the thrust structure comprising the inlet pipe 242A should also be part of the thrust structures, which respectively contain the inlet pipes 242B and 242C.

[00132] It is understood that since the actuator subsystem 150 controls the angular position of one centrally mounted disk 157 (and, in particular, the V-groove 159) relative to the fluid manifold 220, the actuator subsystem controls which of the thrust shoes 260A, 260B and 260C (or neither), which is pushed outward by the action of pressurized drilling fluid.

[00133] In this embodiment, the inward-facing side of each thrust shoe that mates with the corresponding outward-facing ends of the pistons is configured to distribute the force transmitted to the pistons along the piston stroke axis in a generally symmetrical manner over the entire piston stroke. It is understood that since each thrust shoe rotates about a hinge axis generally parallel to the axis of rotation of the deflector subsystem 200, and each piston slides in and out along its stroke axis when mated to the underside of the corresponding thrust shoe, there is the potential for the thrust shoe to transmit greater force with the passage of time on the pistons in one non-axial direction than in the opposite non-axial direction. To compensate for this, the inward facing side of each thrust shoe is inclined so that when the thrust shoes move in and out, the sum of the force vectors transmitted between the thrust shoes and the pistons over their range of stroke is normal to the cylindrical axis of the pistons. Alternatively, the inward facing side of each thrust shoe is not planar, but instead is curved and concave such that when the respective pistons move in both directions, outward and inward, the inward facing side of the thrust shoe contacting the outward facing ends of the pistons is “tilted sideways.” near the outward-facing ends of the pistons in order to in some way “swing on a swing” the entire full stroke relative to the axes of the pistons. In general, this “seesaw” transfers force more symmetrically along the stroke axes of the pistons, resulting in more uniform wear than if the inward side of the thrust shoe is planar. In addition, the inward facing side of each thrust shoe, at the point where it mates with the corresponding pistons, when the BHA 50 is centered in the well, runs perpendicular to the piston stroke axis. This, accordingly, transmits the force received by each thrust shoe to the well wall along the axis of the piston stroke when the BHA 50 is centered.

[00134] In FIG. 10B shows a cross-section identical to that shown in FIG. 2 of the bottom hole assembly 50, but with the bottom hole assembly centered in the wellbore BH in formation G. FIG. 10C shows a cross-sectional view of the deflection subsystem 200, the same as FIG. 10A but shows the bottom hole assembly 200 centered in the wellbore BH as in FIG. 10B, along line B-B in FIG. 10B. In fig. 10C, it can be seen that the undersides of all thrust shoes are normal to their respective piston axes when the bottom hole assembly 50, and in particular the diverter subsystem 200, is centered in the wellbore BH.

[00135] An upstream end view of deflector subsystem 200 is shown in FIG. eleven.

[00136] In FIG. 14 is an upstream end view of a fluid manifold 420 for an alternative embodiment diverter subsystem 400, and FIG. 15 is an isometric view of the fluid manifold 420 with the internal fluid pipes shown in dotted lines. The fluid manifold 420 has an upstream surface 422 facing the flow of drilling fluid exiting the drill collar 100.

[00137] The upstream surface 422 has a central zone 424 (shown as a dotted line in FIG. 14) and a peripheral zone 425 extending from the central zone to the periphery of the upstream surface 422. In this embodiment, the central zone 424 includes two (2) valve windows 426A and 426B. The valve ports 426A and 426B are flush with and open to the upstream surface 422. Each of the valve ports 426A and 426B is in fluid communication with a corresponding valve pipe 440A, 440B extending downstream of the upstream surface 422 of the fluid manifold 420. As described below, when the drill collar 100 is screwed onto the diverter subsystem 400, a disk 157 protruding from the actuator subsystem 150 is advanced toward the upstream surface 422. The disk 157 is thus centered relative to the central region 424 of the upstream surface. 422. Disc 157 is thus associated with valve ports 426A and 426B when deflector subsystem 400 is coupled to drill collar 100. A cylindrical nipple 158 extending from the downstream surface of disc 157 contacts a portion of central zone 424 between portions 426A and 426B valve. In embodiments, a short cylindrical cup (not shown) with walls parallel to the axis of rotation of the BHA 50 extends slightly downstream of the upstream surface 422. This is provided to receive a short cylindrical nipple 158 to assist in maintaining the disk 157 in a central position facing central zone 424. In such embodiments, the short cylindrical cup must be sized to interfere very little with the rotation of the short cylindrical nipple 158.

[00138] By controlling the angular position of the disk 157 relative to the central zone 424, the disk 157 locks or unlocks the valve windows 426A and 426B. This allows the actuator subsystem 150 to control the pumping of pressurized drilling fluid through the drill string and into the diverter subsystem 400 as it enters any of the valve ports 426A and 426B.

[00139] In a peripheral region 425 located upstream of surface 422, two (2) flow ports 428A and 428B are located flush with and open to the upstream surface 422. In this embodiment, each of the flow ports 428A and 428B is in fluid communication with a corresponding flow pipe 429A and 429B. Flow tubes 429A and 429B extend downstream from the upstream surface 422 of the fluid manifold 420. The disk 157 is sized only to interface with the central zone 424 of the upstream surface 422 and not substantially with the peripheral zone 425 of the upstream surface 422. The flow ports 428A and 428B remain substantially unobstructed by any or valves. Thus, the main flow of drilling fluid can pass downstream to the drill bit 300 without being otherwise affected by valve operation.

[00140] In this embodiment, as valve conduits 440A and 440B extend downstream from upstream surface 422 to a respective abutment structure, each extends generally linearly along the central axis of fluid manifold 420. In addition, as flow tubes 429A and 429B extend downstream from upstream surface 422, each extends generally linearly along the central axis of fluid manifold 420. Thus, two main flows of drilling fluid are formed when the incoming drilling fluid reaching the upstream surface 422 of the fluid manifold 420 continues to flow through the fluid manifold 420 out of the respective outlet ports 430A, 430B to pass into the drill bit 300. A second threaded portion 406 at the downstream end of the deflector subsystem 400 may be screwed to a corresponding threaded portion of the drill bit 300 to allow pressurized fluid exiting the deflector subsystem 400 to move into the drill bit 300. It can be seen that flow pipes 429A and 429B extends in the housing along the axis of rotation of the deflection system, but is closer to the periphery than the smaller valve pipes 440A, 440B, which extends in the housing closer to the deflection subsystem 400 and along its axis of rotation. In this configuration, especially in the area of the thrust structure, the cylinder depths and piston lengths can be closer to the axis of rotation. This is compared to how close the cylinder depths and pistons lengths would allow to extend if larger flow tubes 429A, 429B (or a single flow tube) passed through the center of the housing 402 and thus between the thrust structure and the axis of rotation.

[00141] In FIG. 16 is a side view of a deflection subsystem 400 having a housing 402 including a fluid manifold 420, and FIG. 17 shows a cross-section of the deflection subsystem 400 along line G-G in FIG. 16. The deflector subsystem 400 is the same as the deflector subsystem 200, comprising a first threaded portion 404 at the upstream end and a second threaded portion 406 at the downstream end.

[00142] Valve pipe 440A, when valve window 426 is not blocked by disk 157, supplies pressurized drilling fluid to a corresponding thrust structure. The valve pipe 440A extends past the downstream surface of the fluid manifold 420 a short distance to be inserted into a corresponding inlet pipe 442A of a suitable thrust structure to provide a connection between the pipes 440A, 442A. In this embodiment, the thrust structure corresponding to the valve pipe 440A includes an inlet pipe 442A and two cylinders 450AA and 450AB in fluid communication with the valve pipe 440A through the inlet pipe 442A. The thrust structure also includes pistons 455AA and 455AB sliding in the respective of two cylinders 450AA and 450AB. In turn, pistons 455AA and 455AB mate with the underside of one thrust shoe 460A. The thrust shoe 460A is pivotally attached to the outer portion of the housing 402 of the deflection subsystem 400 at its periphery and is rotatable outwardly about the axis of rotation as the piston or each piston 455AA and 455AB moves outwardly under hydraulic pressure. Thus, the thrust shoe 460A extends from the periphery of the housing 402 under this condition.

[00143] When disk 157 allows drilling fluid to enter valve port 426, inlet pipe 442A supplies pressurized drilling fluid to cylinders 450AA and 450AB. Using the back pressure from the throttle in the outlet pipe 252A, this in turn causes the pistons 455AA and 455AB to be pushed outward (upward, in FIG. 17) while together pushing the thrust shoe 460A outward and against the borehole wall. The thrust shoe 460A contacts the borehole wall and pushes the BHA 50 in the opposite direction. When the valve window 426 is then blocked, the fluid pressure in the respective cylinders 450AA, 450AB drops and the thrust shoe 460A moves to its neutral position on the housing 402. This occurs simply because the force acting on the outside of the thrust shoe 460A, transmitted by the wall, in this point is not counteracted by sufficient force on the underside of the thrust shoe 460A through the pistons 455AA, 455AB. The drilling fluid passes further downstream of the thrust structure through the outlet pipe 452A to then meet and connect with the main pressurized fluid stream before exiting the diverter subsystem 400.

[00144] Likewise, valve pipe 440B, when valve port 426B is not blocked by disk 157, delivers drilling fluid under pressure to a corresponding thrust structure. In this embodiment, the thrust structure corresponding to the valve pipe 440B includes an inlet pipe 442B and two cylinders 450BA and 450BB in fluid communication with the valve pipe 440B through the inlet pipe 442B. This thrust structure contains pistons 455BA and 455BB sliding in the respective of two cylinders 450BA and 450BB. In turn, the 455BA and 455BB pistons mate with the underside of a single 460B thrust shoe. The thrust shoe 460B is also pivotally coupled to the outer portion of the housing 402 of the deflector subsystem 400 and can be rotated outwardly about the axis of rotation as the piston or each piston 455BA and 455BB moves outwardly under hydraulic pressure. Thus, the thrust shoe 460B extends from the periphery of the housing 402 under this condition.

[00145] When disk 157 allows drilling fluid to enter valve port 426B, inlet pipe 442B supplies pressurized drilling fluid to cylinders 450BA and 450BB. This, in turn, causes the pistons 455BA and 455BB to be pushed outward (downward in FIG. 17), while together pushing the thrust shoe 460B outward and against the borehole wall. The thrust shoe 460B, in contact with the borehole wall, pushes the BHA 50 in the opposite direction. When the valve window 426B is then blocked, the fluid pressure in the respective cylinders 450BA, 450BB drops and the thrust shoe 460B moves to its neutral position on the body 402. This occurs simply because the force acting on the outer side of the thrust shoe 460B, transmitted by the wall, in this point is not counteracted by sufficient force acting on the underside of the thrust shoe 460B through the pistons 455BA, 455BB. The drilling fluid travels further downstream to then meet and connect with the main pressurized fluid stream before exiting the diverter subsystem 400.

[00146] In this embodiment, the inward facing side of each thrust shoe mating with the respective outward facing ends of the pistons is shaped to generally symmetrically distribute the force it imparts to the pistons along the piston stroke axis, across the piston stroke length. It is understood that since each thrust shoe rotates about a pivot axis generally parallel to the axis of rotation of the deflector subsystem 400, and each piston slides in and out along the axis of its stroke as it mates with the underside of the corresponding thrust shoe, there is the potential for the thrust shoe to transmit more force over time on the pistons in one non-axial direction than in the opposite non-axial direction. To compensate for this, the inward facing side of each thrust shoe is inclined so that when the thrust shoes move in and out, the sum of the force vectors transmitted between the thrust shoes and the pistons over their range of stroke is normal to the cylindrical axis of the pistons. Alternatively, the inward-facing side of each thrust shoe is not planar, but is instead curved convexly so that when the respective pistons move in both directions, outward and inward, the inward-facing side of the thrust shoe contacting the outward-facing ends of the pistons “leans sideways” near the facing ones. outwards of the ends of the pistons in order to in some way “swing on a swing” the entire full stroke relative to the axes of the pistons. In general, this “seesaw” transfers force more symmetrically along the piston strokes, resulting in more uniform wear than with an inward-facing planar side of the thrust shoe. In addition, the inward facing side of each thrust shoe at the point where it mates with the corresponding pistons when the BHA 50 is centered in the well is perpendicular to the piston stroke axis. This, accordingly, transmits the force received on each thrust shoe by the well wall along the axis of the piston stroke when the BHA 50 is centered.

[00147] In FIG. 18 shows a cross-section of the deflection subsystem 400 along line H-H in FIG. 17. In FIG. 19 is an upstream end view of the deflection subsystem of FIG. 16.

[00148] In FIG. 20 is a cross-sectional view of the deflection subsystem of FIG. 16, along line L-L in FIG. 19. The throttling stage 408A in the flow pipe 410A of the fluid manifold 420 creates a back pressure, causing the drilling fluid to operate at sufficient hydraulic pressure to move through the valve pipe 240A. A similar, not shown, throttling stage in flow pipe 410B of fluid manifold 420 also contributes to the back pressure.

[00149] With fluid manifold 420, valve pipes 440A and 440B extend generally centrally in deflector subsystem 400, and flow pipes 410A and 410B extend generally peripherally. This configuration leaves room for the valve tubes 440A and 440B to be positioned closer to the axis of the deflector subsystem 400 than, for example, the valve tubes for the deflector subsystem 200. In each configuration of the deflector subsystem 200 or 400, effective coupling with a centrally mounted actuator subsystem is possible. one disk, such as the actuator subsystem 150, due to their equally centrally mounted valve ports. This provides the useful ability to control multiple thrust structures using a single disc. However, in addition, since the valve pipes 440A and 440B of the deflector subsystem 400 are mounted centrally, and the flow pipes 410A and 410B are mounted somewhat peripherally, the valve pipes 440A and 440B can be coupled to a downstream thrust structure having deeper cylinders 450AA , 450AB, 450BA and 450BB. Since the 450AA, 450BA, 450BA and 450BB cylinders can be deeper, the cross -sectional area of the corresponding pistons 455AA, 455AB, 455BA and 455BB can be performed by a wider, which does not cause an appropriate distortion or seal of the piston 455AA, 455BA and 455BB in cylinders 450AA, 450AA , 450BA and 450BB, due to increased adhesion. Because the thrust force transmitted to the thrust shoes 460A and 460B is linearly correlated with the cross-sectional area of the piston, the deflector assembly 400 can transmit a thrust force to the borehole wall that is greater, all other factors being equal.

[00150] The deflector subsystem 400 is an example of a configuration in which the proximal components of the thrust structure (i.e., the intake pipes and associated cylinder bottoms) extend inwardly very close to the axis of rotation of the deflector subsystem 400. These components are capable of passing very close to the axis of rotation of the deflector subsystem 400, since the flow pipes, which must be large enough to provide sufficient flow of drilling fluid through the deflector subsystem 400, are installed in the deflector subsystem 400 so as not to lie between ("in between") these closest components to the axis thrust structure and the axis of rotation of the deflection subsystem 400. As can be seen in FIG. 18, flow tubes 410A and 410B are decoupled from the axis of rotation of the deflector subsystem 400 (on page FIG. 18) in a direction different from that in which the components of the thrust structure are decoupled from the axis of rotation. For example, roughly speaking, with the orientation of FIG. 18, thrust structures containing cylinders 450AB and 450BB are disconnected from the rotation axis in the north-south direction, and flow pipes 410A, 410B are disconnected from the rotation axis in the east-west direction and are additionally radially spaced at a sufficient distance from the rotation axis to ensure that the sections of the cylinders closest to the axis are closer to the axis of rotation. Allowing the proximal components of the thrust structure to pass close to the axis of rotation of the deflector subsystem provides a longer stroke for the pistons 455AB, 455BB in the corresponding cylinders 450AB, 450BB. As described herein, the long stroke, in turn, provides a larger piston diameter, resulting in greater thrust force than shorter stroke systems due to the reduced risk of misalignment/seizing. It is understood that other configurations are contemplated, including positioning the flow tubes in the deflection subsystem so as not generally to be positioned between the proximal components of the thrust structure and the axis of rotation, using similar principles of spacing and decoupling.

[00151] In FIG. 21 shows another side view of the deflector subsystem 400, with one of the thrust structures extended slightly to control the path, according to an embodiment. In fig. 22 shows a cross-section of the deflection subsystem 400 along line G-G in FIG. 21. In FIG. 22, a convergence device 470 is included in a housing 402 downstream of the thrust structures to converge drilling fluid supplied downstream from the thrust structures and out through outlet pipes 452A, 452B, where the drilling fluid is supplied through flow pipes 410A, 410B prior to the entry of the pooled drilling fluid into the drill bit 300.

[00152] In FIG. 23 shows a cross-section of the deflection subsystem 400, including the flow convergence device 470, along the line H-H in FIG. 22. In FIG. 24 is another end view of the upstream deflector subsystem 400, and FIG. 25 shows a cross-sectional view of the deflection subsystem 400, including the flow convergence device 470, along the line R-R in FIG. 24.

[00153] The flow convergence device 470 functions to reintegrate multiple flows of drilling fluid generated upstream of the thrust structure by the fluid manifold 420 at a point downstream of the thrust structures. The converging device 470 provides one combined and integrated flow of drilling fluid to the drill bit 300 rather than multiple separate flows. Thus, the mud velocity and pressure represented at the drill bit 300 by the diverter subsystem 400 including the flow convergence device 470 can be generally uniform.

[00154] In FIG. 26 is an end view of the upstream convergence device 470, and FIG. 27 shows a cross-section of the flow convergence device 470 along the line P-P in FIG. 26.

[00155] The converging device 470 is mounted downstream of the thrust structures and has an upstream surface 472 facing the flow of drilling fluid through flow pipes 410A, 410B and outlet pipes 452A, 452B. The upstream surface 472 has a central zone with a planar surface including two (2) smaller flow convergence pipes 476A, 476B aligned with the outlet pipes 452A, 452B. The peripheral zone of the upstream surface 472 is tapered downstream of the planar surface of the central zone. Two pipes 478A, 478B of larger diameter bringing the flows to one point of the device are made with a through passage through the central and peripheral zones. The smaller diameter one-point convergence tubes 476A, 476B are short and terminate at the upstream end of the chamber 480. The larger diameter one-point convergent tubes 478A, 478B are inclined toward the chamber 480 to receive drilling fluid near the periphery of the upstream flow of the surface 472 and feed it inward to the axis of rotation of the deflector subsystem 400. The drilling fluid flows entering the chamber 480 through the pipes 476A, 476B, 478A and 478B are reconverged and mixed to suppress eddies and turbulence to produce an overall uniform single output stream drilling fluid in chamber 480, which can then exit chamber 480 through flow diverter opening 482 into drill bit 300.

[00156] In FIG. 28 shows an upstream isometric view of the flow convergence device 470, and FIG. 29 shows an upstream isometric view of the flow convergence device 470, with the internal fluid pipes shown in dotted lines.

[00157] In FIG. 30 is a cross-sectional view of a bottom hole assembly (BHA) actuator subsystem 350 of an alternative embodiment 500 housed in a drill collar 100. The BHA 500 in this embodiment is connected to the bottom hole string in a manner similar to BHA 50.

[00158] In FIG. 31 is an enlarged view of a downstream portion of actuator subsystem 350, and FIG. 32 shows an isometric enlargement of portions of the downstream portion of the actuator subsystem 350. Similar to the actuator subsystem 150, the actuator subsystem 350 is housed in the tube 152 and includes an actuator 164, that is, in this embodiment, a motor/gearbox assembly 164. In this embodiment, the output shaft of the motor/gearbox assembly 164 is axially coupled through a coupling 168 to the shaft of the bevel gear 370. The bevel gear 370 rotates when driven through the coupling by the motor/gearbox 164 about an axis of rotation corresponding to the axis of rotation of the BHA 500. The bevel gear 370, in turn, mates with bevel gear 372. Bevel gear 372 can rotate with a shaft running normal to the axis of rotation of BHA 500. At the opposite end of this shaft is a standard gear whose teeth mesh with a corresponding gear in crankshaft assembly 374. The crankshaft assembly 374 rotates about the normal axis of rotation of the BHA 500 in response to the transmission of power from the engine/gearbox 164 through the coupling 168 and the bevel gears 370, 372. As the crankshaft assembly 374 rotates in this manner, the coupling rods 376A, 376B of the assembly 374 the crankshaft moves the corresponding poppet valve shafts 378A, 378B up and down in the upstream and downstream directions. This, in turn, moves the corresponding poppet valves 380A, 380B in and out of the engagement with the corresponding valve ports 426A, 426B of the fluid manifold 420. Thus, the actuator assembly 350 can lock or unlock the valve ports 426A, 426B to control the flow of pressurized drilling fluid to the corresponding thrust structure. In this embodiment, the valve windows 426A, 426B may have slightly beveled openings to receive the slightly beveled ends of the poppet valves 380A, 380B to provide some direction for centering the poppet valves 380A, 380B in the valve windows 426A, 426B to effectively seal them upon contact.

[00159] It is understood that, due to the design of the crankshaft assembly 374, unlike the actuator assembly 150, the actuator assembly 350 cannot be controlled to lock both valve ports 426A, 426B simultaneously. Therefore, with actuator assembly 350, a neutral position can be achieved by continuing to actuate all thrust structures in a pseudo-random or some other automatic counter mode as the drill string rotates.

[00160] Although the valve design using poppet valves 380A, 380B is more complex than the valve design using disc 157, it may have some advantages. For example, due to valve acceptance into windows 426A, 426B to some extent, poppet valves 380A, 380B may provide more reliable window locking than disk 157. Additionally, the poppet valve design may be able to better withstand interference from certain absorption control materials ( LCM), such as sawdust, which can be pumped downhole along with the drilling fluid than the disc design described above. Also additionally, the poppet valve design may be less prone to galling from the accumulation of solids under the disk, such as disk 157.

[00161] Although embodiments have been described with reference to the drawings, those skilled in the art will appreciate that variations and modifications may be made without departing from the spirit, scope and purpose of the invention as defined by the appended claims.

[00162] For example, although in the embodiments described herein, the actuator subsystem is included in a drill collar located immediately upstream of the diverter subsystem, alternatives are possible. For example, the actuator subsystem may alternatively be included in another drill string component immediately upstream of the diverter subsystem, such as a drill pipe, measurement while drilling (MWD) or logging while drilling (LWD) component.

[00163] Additionally, although in the embodiments described herein each of the thrust structures includes two cylinders with corresponding pistons, alternatives are contemplated in which each of the thrust structures has only one cylinder with a corresponding piston or more than two cylinders with corresponding pistons . Alternatives are also contemplated where there are more than three thrust structures in the deflection subsystem. It is clear that, in order to realize a larger number of thrust structures, the number of valve ports extending from the fluid manifold must be correspondingly greater. This, accordingly, requires dimensional adjustments in the disk, fluid manifold and other structures.

[00164] In addition, different disc configurations for the disc valve component are required where the valve ports are not equally spaced on center in the area of the upstream surface of the fluid manifold, or where additional valve ports are subject to blocking at any given time.

[00165] Additionally, although in embodiments a nipple extends from a downstream surface of a valve disc portion to mate with a corresponding cup in an upstream surface of a fluid manifold, alternatives are possible. For example, embodiments are contemplated in which there is no such nipple/cup pair, as well as embodiments in which such a nipple is provided without a cup mate, or with a cup mate that extends slightly upstream of the surface, and not downstream from it. Variations are possible.

[00166] In addition, although the described embodiments include a fluid manifold as a separate component in the deflection subsystems, alternatives are possible in which fluid flows are routed between valve ports and flow ports by a structure integral with the deflection subsystem. For example, fluid flows may be routed by structures integral to the deflector subsystem housing such that the upstream surface described herein for manifolds or a functionally equivalent structure is itself an alternative integral part of the housing rather than part of a separate manifold component. In addition, alternative designs for diluting fluid flows may be proposed for specific embodiments described herein.

[00167] In addition, although the described embodiments include a convergence device as a separate component, with deflection subsystems downstream of the thrust structures, the convergence device may alternatively be a structure formed within the housing itself.

[00168] Additionally, although in the described embodiments the output shaft 154 of the actuator subsystem 150 passes through both the axial load thrust bearing set 172 and the radial bearing set 174, alternatives are possible in which the output shaft 154 is otherwise held in line axially and/or radially or without any of the sets 172, 174, or without one or the other of them.

Claims (43)

1. Path-controlled bottom hole assembly (BHA), containing: a drill string component including an actuator subsystem, the actuator subsystem comprising an actuator with an output shaft for selectively rotating the valve disk about an axis of rotation of the BHA; wherein the actuator subsystem further comprises: position marker on the output shaft; a position sensor in proximity to the output shaft, wherein the position sensor and the position marker cooperate, when the position marker is rotated with the output shaft to a position adjacent the position sensor, the position sensor responsively transmits a signal to the actuator subsystem for use in controlling the angular orientation of the valve disk; wherein the BHA further comprises a deflector subsystem extending between the drill string component and the drill bit, the deflector subsystem receiving a flow of pressurized drilling fluid through the drill string component and comprising: frame; a plurality of thrust hydraulic structures associated with the periphery of the housing; a plurality of central valve tubes in the housing for supplying drilling fluid for actuating a corresponding one of the thrust hydraulic structures; And a plurality of peripheral flow pipes in the housing for supplying drilling fluid to the drill bit, the flow pipes being located closer to the periphery than the central pipes of the valve, in this case, according to the selected angular orientation of the valve disk relative to the valve pipes, the entry of pressurized drilling fluid into the valve pipes is selectively ensured or blocked. 2. Path-controlled BHA according to claim 1, in which the deflection subsystem additionally contains: a flow convergence device located downstream of the thrust structures, wherein the flow convergence device includes pipes of a single point flow convergence device for receiving and converging drilling fluid flows from the central valve pipes and peripheral flow pipes into one outlet flow up to the entrance to the drill bit. 3. BHA controlled along the trajectory according to claim 1, additionally containing in the housing: a fluid manifold with an upstream surface having: a peripheral zone including flow windows, each of which is connected to a corresponding one of the peripheral flow pipes; and a central zone including valve ports, each of which is connected to a respective one of the valve central tubes, the central zone mating to the disk to block or subsequently allow entry of drilling fluid into the valve ports according to a selected angular orientation of the disk relative to the upstream surface. . 4. The trajectory-controlled BHA according to claim 3, in which the fluid manifold is fixed in the housing. 5. Path-controlled BHA according to claim 3, in which the fluid manifold includes: two flow windows; And two valve windows. 6. The path-controlled BHA of claim 5, in which each of the two peripheral flow pipes runs downstream parallel to the axis of rotation of the deflection subsystem. 7. Path-controlled BHA according to claim 1, in which each thrust structure contains: entrance window; at least one cylinder in fluid communication with the inlet window; a piston moving in each of the at least one cylinder in an inward and outward direction relative to the axis of rotation of the deflection subsystem; a thrust shoe mating to the piston or each piston at a periphery of the housing, wherein the thrust shoe is hinged relative to the housing and is rotatable outwardly relative to the axis of rotation as the piston or each piston is moved outwardly by hydraulic pressure to thereby extend from the housing. 8. The path-controlled BHA of claim 1, wherein the actuator subsystem is fixedly mounted and centrally mounted in the fluid pipe of the drill string component to rotate with the drill string component about the axis of rotation of the drill string. 9. Path-controlled BHA according to claim 8, in which the actuator subsystem contains: a pipe sized and centrally mounted in the fluid pipe to leave an annular flow zone for drilling fluid between the pipe and an internal wall surface of the fluid pipe, the actuator being housed in the pipe; wherein the output shaft extends axially beyond the downstream end of the pipe to mate with the disc valve component, the valve disc being part of the disc valve component. 10. The path-controlled BHA of claim 9, wherein the disc valve component further comprises a coupling for receiving the output shaft. 11. The path-controlled BHA of claim 10, wherein the output shaft is keyed to be secured in a corresponding slot in the coupling of the disc valve component to prevent rotation relative to the coupling, but to allow axial sliding relative to the coupling. 12. Path-controlled BHA according to claim 1, in which the actuator contains an electric motor and a gearbox. 13. The path-controlled BHA of claim 1, further comprising a set of axial bearings in the tube to receive a passing output shaft to axially support the output shaft along the axis of rotation of the drill string component. 14. The trajectory-controlled BHA according to claim 9, in which the actuator subsystem additionally contains: a control board in the pipe in communication with the actuator to control the rotation angle of the output shaft; a power supply for powering at least the control board and the actuator; And a sensor unit for measuring the orientation of the Earth's magnetic field and the gravity vector. 15. The trajectory-controlled BHA according to claim 1, in which the position sensor is a Hall sensor and the position marker is a magnet. 16. The path-controlled BHA according to claim 1, in which the valve disc is annular and has a V-shaped groove that allows the passage of drilling fluid downstream of the valve disc into the selected one of the central pipes of the valve. 17. The path-controlled BHA of claim 16, wherein the V-groove is sized to accommodate multiple valve center tubes and a valve disc to selectively orient the groove to allow drilling fluid to enter only one valve center tube at a time. 18. The path-controlled BHA of claim 17, wherein the V-groove is sized to accommodate multiple valve center tubes and a valve disk to selectively orient the groove to prevent drilling fluid from entering any of the valve center tubes. 19. The trajectory-controlled BHA according to claim 7, in which the inward-facing side of each thrust shoe is configured to symmetrically distribute the force transmitted to the corresponding one or more pistons along the axis of the piston stroke, over the entire length of the piston stroke. 20. The path-controlled BHA of claim 19, wherein the inward facing side of each thrust shoe is configured, when the BHA is centered in the well, to transmit force to a corresponding one or more pistons in alignment with the corresponding axes of the piston stroke.