TECHNICAL FIELD

The present invention generally relates to downhole wellbore devices and, more specifically but not exclusively, to downhole rotational indexing of wellbore drill string devices.

BACKGROUND

Downhole wellbore indexing tools are necessary to position other devices and tools that are configured together on a drilling or tubing string, in the course of drilling and extraction of oil, gas, water and minerals. Many of the large oilfield tool providers have some rotational devices to position their downhole tools and most are manually controlled or activated from the surface. As problems are encountered or rotation not verified, the drilling or tubing string must be withdrawn and inspected or repositioned. There are no current indexing alternatives to ensure a precise rotation to nearest one degree or programmable rotational devices that can be set or adjusted whenever required, unless the indexing tool is withdrawn and removed from the wellbore upon each successive rotation to check for accuracy.

There are other types of hydraulic and electrical motors that serve as rotational devices downhole, and the suspension string itself may be capable of rotating the downhole string and tools, however a drilling or tubing string alone is incapable of providing a precise controlled rotation and will frequently require hydraulic or electrical motors to provide a drive an additional mechanism downhole to position the tools. At high pressure, under fluid and at depth within the wellbore additional elements of uncertainty are common, affecting such tools that utilize motors and their ability to rotate at the desired rates and distances. High pressure environments downhole pushing inward on the rotating components of the tool, create frictional forces that add unique effects on the devices, again affecting the actual expected results and indexing positions of the rotating tools.

Even when the drilling or tubing string is rotated on surface there are no assurances that the desired rotation is achieved at the selected depth downhole. Adding length to the string significantly increases weight and uncertainty of rotational accuracy, as does the angle of the wellbore with current methods, proving to be a very ineffective in deviated or horizontal wells due to friction and drag.

Wellbore solid particles are also a problem for rotational devices that do not actuate within an enclosed, sealed and protected environment.

There is a need to provide improved downhole wellbore indexing devices and methods that enable wellbore string device processing to be carried out more effectively and efficiently.

SUMMARY

According to one aspect, there is provided a rotational indexing device for indexing a wellbore device downhole. The rotational indexing device can comprise a body configured for inserting downhole in a wellbore; a rotary actuator configured for rotationally indexing a wellbore device; an electronic controller for controlling the rotary actuator; wherein the electronic controller is electronically configured to cause the rotary actuator to automatically rotate according to a predetermined indexing sequence; and a power source for powering the controller; wherein the rotary actuator, the controller and the power source are operatively carried on the body for inserting downhole in the wellbore; and wherein, when the indexing device is disposed downhole and the rotary actuator is operatively coupled to the wellbore device to be rotated, the indexing device automatically rotates the wellbore device through successive rotational steps according to the predetermined indexing sequence.

By carrying an electronic controller and power source on the indexing body and configuring the controller to cause the rotary actuator to rotationally index the wellbore device according to a pre-determined indexing sequence, continuity of the wellbore device action and performance is maintained without any surface intervention. This reduces and eliminates additional withdrawals and insertions of the drilling or tubing string and devices from the wellbore that were otherwise necessary for resetting or checking on the status of various devices and tools downhole.

In one example, the electronic controller is electronically configured to cause the rotary actuator to index the wellbore device through successive rotational steps at time intervals predetermined to permit cutting, jetting or other wellbore tool functions to be performed by the wellbore device between successive rotational steps.

According to another aspect, there is provided an apparatus for causing an indexing device to index a wellbore device downhole, the apparatus comprising a memory, such as a computer readable storage medium, storing instructions which, when processed by one or more processors, cause: initiating timer; in response to an output of the timer, rotating an electrical mechanical drive carried on the indexing device downhole through successive rotational steps according to a predetermined indexing sequence.

According to yet another aspect, there is provided a method for rotational indexing a wellbore device by an indexing device, the indexing device comprising a body configured for inserting downhole in a wellbore; a rotary electromechanical drive configured for operably coupling a wellbore device to be indexed; a electronic controller for controlling the rotary actuator; and a power source for powering the controller. The method can comprise configuring the electronic controller to cause the electro-mechanical drive to automatically rotate according to a predetermined indexing sequence; operatively coupling the electro-mechanical drive to the wellbore device for rotating the wellbore device; inserting the indexing device downhole; automatically rotating the wellbore device in the wellbore downhole, utilizing the indexing device, through successive rotational steps according to the predetermined indexing sequence.

According to yet another aspect, there is provided a wellbore system for indexing a wellbore device. The system can comprise a wellbore device for inserting downhole in a wellbore: a rotational indexing device for rotational indexing the wellbore device downhole; wherein the rotational indexing device comprises: a body configured for inserting downhole in the wellbore; a rotary actuator configured for operably coupling the wellbore device to rotate the wellbore device; a electronic controller for controlling the rotary actuator; wherein the electronic controller is electronically configured to cause the rotary actuator to automatically rotate according to a predetermined indexing sequence; and a power source for powering the controller; wherein the rotary actuator, the controller and the power source are operatively carried on the body for inserting downhole in the wellbore; and wherein, when the indexing device and wellbore device are disposed downhole and the rotary actuator is operatively coupled to the wellbore device to be rotated, the indexing device automatically rotates the wellbore string device or device thereof through successive rotational steps according to the predetermined indexing sequence.

According to yet another aspect, a method is provided for jetting a wellbore with an automated jetting system, the automated jetting system comprising: a lateral jetting string system for inserting into a wellbore, the lateral jetting string system including a directional guide for enabling a jetting hose to be radially deflected towards the wellbore formation; and an indexing device comprising a body configured for inserting downhole in a wellbore, a rotary actuator for operably coupling to the directional guide of the lateral jetting system; an electronic controller for controlling the rotary actuator; and a power source for powering the controller. The method can comprise configuring the electronic controller to cause the rotary actuator to automatically rotate the directional guide according to a predetermined indexing sequence; operatively coupling the rotary actuator to the directional guide of the lateral jetting system for rotating the directional guide downhole; inserting the indexing device downhole; inserting the lateral jetting system downhole; automatically rotating the directional guide in the wellbore downhole, utilizing the indexing device, through successive rotational steps according to the predetermined indexing sequence.

According to yet another aspect, there is provided a system for jetting a wellbore with an automated jetting system. The automated jetting system can comprise: a lateral jetting string system for inserting into a wellbore, the lateral jetting string system including a directional guide for enabling a jetting hose to be radially deflected towards the wellbore formation; and an indexing device comprising a body configured for inserting downhole in a wellbore, a rotary actuator for operably coupling to the directional guide of the lateral jetting system; an electronic controller for controlling the rotary actuator; and a power source for powering the controller; wherein the electronic controller is configured to cause the rotary actuator to automatically rotate the directional guide according to a predetermined indexing sequence.

BRIEF DESCRIPTION OF DRAWINGS

Specific embodiments of the invention will be described in detail with reference to the following figures.

FIG. 1 illustrates a general electro-mechanical block diagram of an indexing device according to an embodiment;

FIG. 2 illustrates a cross-sectional view of an exemplary assembly of the indexing device components of FIG. 1 according to one embodiment;

FIG. 3 illustrates a general electrical block diagram of the electronics of the device of FIG. 2 according to one embodiment;

FIG. 4 illustrates a programmable interface according to an embodiment;

FIG. 5 illustrates an exemplary computer system capable of implementing a user interface for programming the indexing device according to one embodiment;

FIG. 6 shows an exemplary high level logic flow for an autonomous wellbore downhole rotational indexing device according to an embodiment;

FIG. 7 illustrates a high level flow chart of a method for operating the autonomous wellbore rotational indexing device to index a wellbore device according to one embodiment;

FIG. 8 illustrates a high level flow chart of a method manufacturing an indexing device according to one embodiment.

FIG. 9 illustrates a wellbore system including an indexing device according to an embodiment.

FIG. 10 illustrates an azimuth chart showing one exemplary rotational program of the indexing device of FIG. 9 for casing exit location and lateral jetting according to one embodiment.

DETAILED DESCRIPTION

In the following detailed description of embodiments of the invention, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.

The indexing devices and methods of the embodiments described herein are for rotating a wellbore device within a wellbore. The term wellbore device is defined herein to mean any type or wellbore tool, string device and/or component thereof which is to be rotated within a wellbore. Non-limiting examples of such a wellbore device are a wellbore lateral jetting tool component and a whipstock and milling assembly. The wellbore in which wellbore device is to be rotated may be orientated in vertical trajectory but may be oriented any other trajectory, such as but not limited to a horizontal trajectory.

Technical features described in this application can be used to construct various wellbore downhole indexing devices, systems and methods. In one approach, an autonomous programmable downhole rotational indexing device is provided, for substantially precisely and programmatically imparting rotational motion to a wellbore device, such as a string or internal tool device, under the mechanical control of the indexing device. It will be appreciated that the indexing device of one or more embodiments may be configured to provide less than precise or substantially precise indexing.

In another approach, a wellbore system has a wellbore device and the aforementioned indexing device. In one example, the wellbore device comprises a directional guide for radially guiding a jetting hose and/or fluid therethrough to an opening to the wellbore formation to which the directional guide is aligned. The indexing device is programmed for sequentially indexing the directional guide of the wellbore device in alignment with respective corresponding ports or openings circumferentially distributed around the wellbore so as to enable jetting of the formation to be sequentially performed through the respective openings.

Reference will now be made to the accompany drawings in which FIG. 1 is a system block diagram providing a general overview of a wellbore downhole rotational indexing device according to an embodiment. Indexing device 1 has a body 2 configured for inserting downhole in a wellbore. Carried on body 2 is an electronic controller 3, a rotary actuator 4 for operatively coupling to a wellbore device 6 to be rotated in the wellbore, and a power source 5 for powering the controller and rotary actuator. Controller 3 is electronically configured to cause the rotary actuator to automatically rotate according to a predetermined indexing sequence. When indexing device 1 is disposed downhole and the rotary actuator 4 is operatively coupled to the wellbore device, indexing device 1 automatically rotates the wellbore device through successive rotational steps according to the pre-determined indexing sequence.

The automated indexing sequence is predetermined by the electronic controller hardware and/or software configuration and depends on the particular wellbore application. The automated indexing sequence is predetermined such that indexing device is capable of indexing the wellbore device through successive steps at predefined time intervals that are selected to permit cutting, jetting or other wellbore tool functions to be performed by the wellbore device between successive rotational steps.

By carrying an electronic controller and power source on the indexing body and configuring the controller to cause the rotary actuator to rotational index the wellbore device according to a pre-determined indexing sequence, continuity of the wellbore device action and performance is maintained without any surface intervention. This reduces and eliminates additional withdrawals and insertions of the drilling or tubing string and devices from the wellbore that were otherwise necessary for resetting or check on the status of various devices and tools downhole.

In the example of the indexing device of FIG. 1, electronic controller 3 is a digital controller. The digital controller comprises one or more processors and memory containing instructions, which when executed by the one or more processors, cause the rotary actuator to automatically rotate in the predetermined indexing sequence. In another non-limiting example, the controller is an analog controller.

Controller 3 initiates the indexing sequence in response to an internal trigger signal, such as from an internal pre-determined timer signal. Alternatively, controller 3 initiates the indexing sequence in response to a manual trigger, such as an electro-mechanical switched activated by a user, or in response to a sensor or transducer signal, such as a signal from a transducer or sensor carried on the indexing body 2 or carried on an external device.

In one example of the indexing device of FIG. 1, the rotary actuator is an electromechanical drive comprising an electrical stepper motor or other type of electrical servo motor. However, other types of rotary actuators may be adopted such as pneumatic or hydraulic rotary actuators. Indexing device 1 of FIG. 1 may include a pressure transducer 7, temperature sensor 8 and signal conditioner 6. The pressure transducer and temperature sensors may be carried on indexing device body 2 or carried on external devices and operatively connected to controller 3.

In the example of the indexing device shown in FIG. 1, the indexing sequence is pre-programmable via a programmable user interface 10 operatively connectable to controller 3. Programmable user interface 10 is a remote user interface connectable to input port 9 for interfacing and programming the controller to perform a particular indexing sequence. In another non-limiting example, user interface 10 is a local user interface carried on the body of the index device.

User interface 10 may be a software based user interface such as a graphical user interface comprising a display 11, one or more user input devices 12 and interface software. Alternatively or additionally, user interface may be a physical based user interface comprising function specific buttons, touch sensitive keys and other physical user input devices for programming purposes.

Power source 5 is any type of battery or other portable power source carried on indexing device body 2 for powering the electronic controller, electrical mechanical drive and any other components that require electrical power so that the indexing device is capable of running in an autonomous mode downhole in the wellbore. In one example of FIG. 1, the power source 5 is one or more rechargeable batteries that may be recharged using a suitable battery charger that is connectable to the batteries via an input port 9.

Reference will now be made FIG. 2 which is a cross sectional view showing a non-limiting example of how indexing device components of FIG. 1 are assembled together according to one embodiment. In this non-limiting example, the indexing body of FIG. 1 comprises a protective sealed cylindrical housing 403 of outside diameter 423 and motor-gearbox housing 409 which carries the rotary actuator. Viewing from right to left, end cap 401 provides stability and connection to the internal component carrier and housing 403, to contain a circulation element, with pre-engineered flow ports for secondary low pressure operability within the wellbore and access to the input and output ports of the electronics. Electronics 407 includes the electronic controller and associated electrical components of FIG. 1. The power source is a battery 405 for powering servos as well as the electronics 407 in their insulated compartment.

In FIG. 2, the rotary actuator is an electrical-mechanical drive comprising electrical motor and gearbox 411. A mechanical coupling is provided to operatively couple the motor to the wellbore device (not shown) to be indexed. The mechanical coupling includes a shaft 415 which couples the motor and gearbox 411 at one end and which has an opposite end for operative connection to the wellbore device to be indexed. Shaft coupling 417 with needle roller bearing 419 support the shaft to freely rotate with up shaft needle roller bearing, top sub 425, spring shoulder 427, wave washer 431, rotary seal retainer 433, rotary seal 435, external coupling 437, load ring 439, wave washer 441, and thrust washers 443 are assembled in a cylinder along the string axis for rotational support as well as axial thrust forces. It will be appreciated that such mechanical coupling is but one non-limiting example of mechanical coupling that may be utilized for operatively coupling rotary actuator 411 to a wellbore device. Furthermore, it will be appreciate that, in some applications, such intermediate mechanical coupling may not be part of the electromechanical drive of the indexing device. For example, the electrical motor or other rotary actuator carried on the indexing device body may be configured to directly engage with mechanical coupling that is external of the indexing device, such as the mechanical coupling of the wellbore device to be indexed.

A transducer sub assembly 421 along with transducers strategically placed provides pressure data and stall data to the electronics 407 for further processing. A temperature sensor, pressure sensor and/or flow sensor 443 are also shown supported by the housing 403. At least one power source 405 is used to power the electronics 407 and mechanical drive train to impart rotational repositioning of the drill string.

The high pressure static and rotary seals 433 and 435 are redressable, allowing for the removal and replacement of the seals 435. Pressure transducers, not shown, are included in the electronics and some may actually be placed near a cutter device, not shown. In one example, the indexing device controller retains an accurate log of all pertinent wellbore conditions and events transpiring downhole, that are relevant to the overall operation.

A general block diagram showing one example of the electronics 407 of FIG. 2 is shown FIG. 3. Electronics 407 includes the digital controller, which includes one or more processors 807, an onboard memory 803 and an I/O interface 811 communicating with the servo motor of the rotary actuator electro-mechanical drive for physically turning a shaft. The servo motor with coupled gearbox in the drive train are electronically controlled by the controller in accordance with an executing control program. Memory 803 stores computer program instructions which, when executed by the one or more processors 807, cause the electrical motor servo to automatically rotate in the predetermined indexing sequence. In one example, the digital controller and electrical motor are configured to control the motor to impart precise pre-stored azimuthal rotation angles and rotation delays to the shaft 415. Such precision may be achieved utilizing suitable stepper motors for example.

The autonomous wellbore indexing of FIG. 2 provides ways to substantially precisely index drilling or tubing string, or equipment, tools or devices in the wellbore without having to withdraw and remove the string from the wellbore upon each successive rotation to check for accuracy or resetting it. The indexing device of FIG. 2 actuates within an enclosed and protected environment to accomplish the efficient rotational indexing required to locate the casing holes or exits, and is capable of stepping through a lateral rotational sequence in a harsh environment while being able to take into account and recover from events such as stalls. The indexing device of FIG. 2 is an example of a sealed, precision actuation device that can be programmed to position downhole tools, if necessary, in exactly the right direction once at a desired depth in the wellbore, and to be automatically rotated to additional precise positions at any time required while remaining within the wellbore.

FIG. 4 shows one non-limiting example of the programmable user interface of FIG. 1 for programming the indexing device to perform a particular indexing sequence according to one embodiment. Interface 200 facilitates the autonomous character of the device through pre-programming a pre-set sequence 201 of user inputs that will control the indexer motions in the downhole position. Rotation degree angle 202 input 203 refers to the angular position of the windows. Windows correspond to passageways, holes or exits downhole in the wellbore casing and/or formation itself, or simply circumferential points in space, to which the wellbore device is to be sequentially rotated by the indexing device. The delays refer to the time intervals between successive rotations. Settings of the respective delays and windows, depend on the particular wellbore application and/or type of wellbore string device, tool or component to be rotated.

The windows may for example be evenly or unevenly circumferentially spaced apart from one another. The first window is assigned zero degrees with the remaining windows being spaced from that datum. The 1^stdelay 205 input represents the initial delay in accepted units of time, from the arming time until the device shaft begins to rotate for the first time from initialization. The 2^nddelay 207 input represents the period, in acceptable time units, between the rotations. A minimum time may optionally limit this period to allow for motion and for small errors in timing, so that rotations do not occur without system readiness. In some embodiments, the window spacing is not evenly distributed around the casing circumference. A next pre-set input represents the next rotation movement and a pre-programmed sequence can direct uneven rotation angles at other than evenly spaced windows.

A row of button commands 211 include a Home, Reset, Diagnostics, Screen Refresh and reports. The Home button selection returns the actuator to its home, zero degree, position. The Screen refresh button refreshes the screen. The Reset button clears non-volatile memory and sets Stalls 221, Moves 223, and Maximum Temp 215 sensed and recorded 213 to zero. Sensed and measured parameters are stored and some output read-only variables 213 are displayed. These include Maximum Temperature 215, Temperature 217 in the hole, Battery voltage 219, Stalls 221, Movements 223, and pressure transducer data 225 227.

FIG. 5 illustrates a block diagram of an exemplary computer system capable of implementing the user interface and programming for the indexing device. The computer system 100 is a Central Processing Unit 103, Memory 107, network interface card 111, Display Screen 132, Mass Storage interface 108 for such devices 113 as hard drive(s) removable disk drives, I/O buses 112 and 114, Memory Buses 104, etc. For purposes of illustration, embodiments are provided by way of example in the context of a simple environment for a programmable application for controlling the downhole substantially precise rotational movement with contingency logic branches.

Computer system 100 includes at least one processor unit 103, which obtains instructions and data via a system bus 104 from a main memory 107. Illustratively, the processor is a microprocessor. The main memory 107 could be one or a combination of memory devices, including Random Access Memory 122, dynamic, nonvolatile or backup memory, (e.g., programmable or Flash memories, read-only memories, etc.) and the like. In addition, memory 107 may be considered to include memory physically located elsewhere in a computer system 100, for example, any storage capacity used as virtual memory or stored on a mass storage device 113 or on another computer coupled to the computer system 100 via system bus 104. Illustratively, the main memory 107 contains executable programs, which manage the hardware and control the software programs 105. The ROM 120, BIOS 121, and Operating System 125 are a system of programs, which manage the hardware and software resources for the use and running of application programs. The memory 107 may further contain diagnostic programs 126. In one embodiment, the application is a mechanical component initialization controller.

Program modules 126 and Program data 128 would typically also be resident in main memory 107 along with other programs 125 which can be paged or swapped in from other memory sources, local 108 or networked 117. Software components and objects are but parts of programs, which reside together in various regions of addressable memory and are executed to produce the necessary application functions. Software components and objects themselves can be broken down into data structures and programming logic which use the data structures. Generally, application program modules 126 include processes, programs, objects, components, data structures, etc. that perform particular tasks to manage sensor data, interpret and autonomously execute remedial actions in the form of pre-programmed instructions.

The computer system 100 includes a number of subsystems. Illustratively, these include a mass storage interface 108 in communication with storage device 113, which can be such devices as hard disk drives, optical disk drives, CD/DVD, portable memory, memory sticks/cards, optical storage, at least one input/output (I/O) interface 109 coupled to I/O devices 115 such as modems, wireless broadcaster devices, audio, communication via serial protocol bus 114 such as IEEE 802.xx, Firewire, USB, RS232 etc, and a network interface 111 coupled to a plurality of networked devices 117 which can be mass storage, other computers, wireless devices and other networked devices. The I/O devices 114 may include any combination of externally coupled devices such as displays, keyboards, track point devices, mouse devices, sensor and sensor data output devices and the like. In some embodiments, the I/O devices are integrated, such as in the case of a touch screen or display panel. The networked devices 117 could be displays, desktop, laptop or tablet computers, or network terminals, wireless handheld or other networked computer systems. As such, aspects of the invention can be practiced on a single computer system as well as over a network of computer devices.

A number of program modules may be stored on the mass storage device 113, ROM 120 or RAM 122, including an operating system 125, one or more application programs 126 and program data 128. A user may enter commands and information into the workstation 100 through input serial devices 115 such as a keyboard or pointing device. Other input devices (not shown) may include a microphone, joystick, game pad, satellite dish, scanner, or the like. These and other input devices are often connected to the processing unit 103 through a serial port interface 115 that is coupled to the system bus, but may be connected by other interfaces, such as a parallel port, game port or a universal serial bus (USB). A monitor 132 or other type of display device, not used in the downhole operations, can be connected to the system bus 104 via an interface, such as a video adapter 108. In addition to the monitor, computers typically include other peripheral output devices (not shown), such as speakers and printers, not used in the downhole operational state, can be used in data retrieval and post-processing. Furthermore, the I/O interface 134 is reads input data 136 from transducers, temperature sensors, flow sensors, stress gages and other sensors which allow for the logic to compensate and adjust automatically to the conditions below. The I/O interface 134 also communicates with the servo(s) 136, for commanding rotation movement of the shaft through servos 137 to very precise angles with timed intervals.

In one example, the computer system 100 may operate in a networked environment using logical connections to one or more remote computers, such as a remote computer 117. The remote computer 117 may be another computer, a server, a router, a network PC, a peer device or other common network node, cell-PDA, smartphone and typically includes many or all of the elements described above relative to the computer 100. The logical connections depicted in FIG. 1 include a local area network (LAN) and a wide area network (WAN). Such networking can be extended to mobile devices executing mobile apps as well.

When used in a LAN networking environment, the computer 100 is connected to the local network 117 through a network interface or adapter 111. When used in a WAN networking environment, the computer 100 can connect via modem 115 or other means for establishing communications over the wide area network 117, such as the Internet. The modem 115, which may be internal or external, is connected to the system bus 114 via the serial port interface 109. In a networked environment, program modules depicted relative to the computer 100, or portions thereof, may be stored in the remote memory storage device. It will be appreciated that the network connections shown are exemplary and other means of establishing a communications link between the computers may be used. Computing devices with wireless communications such as cell phones, smartphones, text message devices or other handheld devices running electronic applications or apps in hardware may be used.

As indicated hereinbefore, the system, as described in relation to FIG. 5, can be split and disseminated in several parts or network clouds. All that is required, in the embodiments, is that a system can be provided capable of providing the user interface and programming functionality of the embodiments described herein. Programming can be performed either remotely in the computer system and the program downloaded to the indexing device via a suitable wired or wireless connection to the indexing device controller or can be performed by programming the controller directly via a local or direct user interface. Furthermore, it will be appreciated that in other embodiments, the computer system may be carried on the indexing body itself and may serve as the digital controller of the indexing device or supplement the digital controller for driving the indexing device to index the wellbore string device in the pre-determined indexing sequence.

FIG. 6 illustrates an exemplary high level logic flow diagram for the indexing device according to an embodiment. A person of ordinary skill would understand that the high level logic flow is not limited to the sequence of processes shown in FIG. 6. At power-up logic starts 301 and executes a hardware and software initialization 303. By way of example, if a programming cable for enabling programming, or downloading a predetermined indexing sequence program, to the indexing device is disconnected from the indexing device and the internal battery is connected 305, the timer begins and the device is rotated to its home position 306. This indicates that the device is now in running mode and is going or is soon to be in the downhole state. The pre-set sequence 307 for rotation, and movement delays are then executed in accordance with the stored pre-sets.

The sensors are continuously monitoring 307 and storing data from sensor signals such as, temperature signals, transducer signals, flow signals, pressure, stress, position, proximity, optical, acoustic, vibration, magnetic, force sensor, raising any found threshold exceptions, and raising pre-set action trigger interrupts for real-time autonomous response from the device in the downhole.

Otherwise, the logic threads to the interface program mode 309 which provides for entering a pre-set sequence of rotation and delay commands, and alternatively manages a case statement 311 which waits on user inputs for screen refresh 313, device rotation to home position 315, diagnostics 317 routines, reset of non-volatile memory 319, reporting stored data 325 post processing, and ending the program 323 loop which returns 321 the program execution or loops back to main program 309 mode.

The diagnostics 317 data will record the maximum temperature and pressure encountered, the number of attempts to move and the number of stall conditions encountered. These are stored in non-volatile memory to preserver them after power is turned off. After each sequence, the program may be re-armed by disconnecting and reconnecting power.

Reference will now be made to the method for indexing a wellbore device utilizing the wellbore downhole rotational indexing device according to one embodiment. A general outline of the method 600 for indexing a wellbore device according to an embodiment is illustrated in the flow chart of FIG. 7. Initially, the indexing device is pre-configured by programming it for automatically rotating a string device to be rotated downhole (601). To this end, a user pre-configures the indexing device utilizing the interface 200 to program a pre-determined sequence 201 of user inputs described above that will control the rotational indexing motions whilst downhole. The particular pre-configuration will vary depending on the particular application and type of string device and tool, and/or component thereof to be rotated.

Following pre-configuration process 601, the indexing device is placed in the run mode whereby the program timer begins and the device prepared to be deployed in to a downhole state (602). The autonomous rotational indexing device is operatively coupled to the wellbore device that is to be rotated downhole (603). More than wellbore device can be operatively coupled to the autonomous indexing device. In one example, this operatively coupling can be achieved by coupling the free drive shaft end of the autonomous indexing device (see FIG. 2) to a drive shaft of the string device or tool device, and/or component thereof, to be rotated (not shown). Operatively coupling of the autonomous indexing device to the string device or tool device can be performed either uphole or downhole. Furthermore, the autonomous indexing device can be operatively coupled to the wellbore device such that, in the wellbore, the autonomous indexing device is either uphole or downhole from the wellbore device.

The wellbore device to be rotated is then sequentially rotated automatically by the indexing device through respective predefined and programmed rotational angles at respective predefined time intervals. In the example of the indexing device of FIG. 2, this is achieved by the controller causing the servo motor to rotate the wellbore device through the predefined rotation angles and at the predefined time intervals. Wellbore and/or tool data, such as performance data, is monitored and collected by the autonomous indexing device (605). For example, the pressure, temperature and operational parameters inside the wellbore can be monitored by the autonomous indexing device using the sensors making up part of the autonomous indexing device.

A person of ordinary skill would understand that method 600 is not limited to the sequence of process shown in FIG. 7. For example, the process of running the autonomous indexing device (602) can be performed after operatively coupling the indexing device the wellbore device to be rotated (603). The process of monitoring and collecting tool and/or wellbore data can be performed either before, concurrently and/or after automatically rotating the string device or tool device, or component thereof, with the autonomous indexing device. Furthermore, in one example of the method 600, the autonomous indexing device can already be provided in a pre-configured and programmed condition and is not changed nor modified so that the process 601 of pre-configuring the indexing device is redundant.

In one example, the autonomous rotational indexing device imparts substantially precise torque to an attached wellbore downhole device and is delivers vital wellbore and tool performance data from its sensors. If the transducers signal a stall, no movement to a set threshold shaft torque, the control program will stop and retry in several strategies of wait and retract. In one embodiment, indexing device can send alerts to upground. All performance and sensor data will be stored and logged, for retrieval later.

A method for manufacturing an autonomous wellbore downhole rotational indexing device according to one embodiment will now be described with reference to the accompanying drawings. FIG. 8 shows a high level flow chart outline of a method for an autonomous wellbore downhole rotational indexing. A person of ordinary skill would understand that method 500 is not limited to the sequence of processes shown in FIG. 7. The method steps include designing, making and installing a motor driven shaft inside of a cylindrical housing 503; supporting the shaft in the housing with bearings, washers, lubrication and seals 505; constructing the housing capable of withstanding wellbore downhole environmental conditions 507; assembling the motor driven shaft operatively connected to a servo and gears, to rotate the shaft 509; powering the servo with an independent battery source within the housing 511; electronically coupling the servo to a controller for imparting rotational movement to the shaft upon command 513; securing sensors within the housing to monitor conditions inside and outside the housing 515; electronically coupling the controller to memory, sensors and battery 519; electrically coupling sensors to controller I/O 521; operatively coupling shaft to at least one string device in the downhole to be rotated 523; creating, receiving and storing programming logic into the memory, logic comprising servo commands for rotating shaft with timed rotation angles and set time delays between rotation angle moves 525; programming logic responsive to sensor readings, for autonomous response to stalls and pre-set environmental conditions 527, and for controller executing programming logic for imparting substantially precise pre-defined azimuthal rotation angles and at predefined time intervals to the string device 529.

Reference will now be made to a wellbore system for indexing a directional tool according to an embodiment. The wellbore system has a wellbore string device, comprising or including a rotatable directional guide, and a rotational indexing device for rotational indexing the directional guide downhole in the wellbore. FIG. 9 illustrates one example of such a wellbore system 900. In this particular example, the string device is a lateral jetting system 902 for laterally jetting the formation. The lateral jetting system has a body 903 comprising directional guide 906 which is slidably rotatable inside a casing 905 of the lateral jetting system 902. Rotational indexing device 950 is operably coupled to the lateral jetting system for rotating directional guide 906 inside the casing 905.

In another example, the directional guide may be fixed in the jetting system 902 and the entire lateral jetting system 902 may be rotatable within the wellbore.

Rotational indexing device 950 has electro-mechanical components and assembly thereof according to any one of the examples of the indexing device embodiments described hereinbefore but has a housing/casing and coupling adapted for engagement with the lateral jetting system.

Indexing device 950 is fixedly supported within the wellbore in a manner that enables the indexing device to rotateably index the lateral jetting system directional guide in response to instructions from the indexing device controller. In the particular example of FIG. 9, indexing device 950 is a unitary assembly that is disposed and supported from the lateral jetting system and functions autonomously. In the example of FIG. 9, the coupling end of the indexing device 950 is fixed and supported from the corresponding coupling end of the lateral jetting system 902. Indexing casing end 954 is fixed to complimentary profiled end of lateral jetting system casing 905 such that the indexing device is supported by the lateral jetting system casing.

In other embodiments, the indexing device may be supported in other ways independent from the lateral jetting system but with the indexing device rotary actuator operatively coupled thereto. For example, the indexing device may be arranged in an operating position coupled to the lateral system but supported by a wellbore sidewall structure separate from the lateral jetting system, or supported by a another wellbore string device that is either interposing the lateral jet system and indexing device or disposed on a side of the indexing device opposite the side on which the lateral jetting system is disposed.

Coupling 955 includes a rotational spline 953 operatively connected to the rotary actuator which in this example comprises a stepper motor (not shown in FIG. 9) of the indexing device. Spline 953 is adapted to mate with a corresponding element 956 carried on or operatively coupled to the directional guide 906 such that rotational movement of the rotary actuator rotates guide 906 within casing 905 about the central axis of the casing.

Lateral jetting system casing 905 has a plurality of access ports or jetting orifices 907 distributed circumferentially about the casing. In the example of FIG. 9, the directional guide 906 comprises a jetting trough rotateably mounted within the casing 905 for enabling a jetting hose seated in the trough to be radially deflected towards or into a formation via the ports 907. However, the directional guide can be of any shaped passageway that is capable of serving as a guide for guiding fluid and/or a hose or nozzle from the lateral jetting system outwardly radially into the formation through a port or other jetting orifice with which the directional guide is aligned by the indexing device.

FIG. 9 is an example of the lateral jetting system directional guide 906 aligned with a corresponding hole in the casing 907. Whilst in the example, casing 905 has 4 circumferentially spaced apart holes 907, casing 905 may have any number of holes such as 1, 6, 8 and so on.

The indexing device indexing sequence is programmed via the user interface by setting the index windows to correspond to angular positions of the respective circumferentially spaced casing hole or ports 907 with which the directional guide 906 is to be aligned by indexing device 950 and through which a jetting hose and nozzle (not shown) of the lateral jetting tool will access the formation for the purpose of lateral jetting and extended reach stimulation. The delays are set to so that there is sufficient time between rotations for lateral jetting to be performed by the lateral jetting system. When indexing device 950 and lateral jetting system 902 are disposed downhole with the indexing device operatively coupled to the directional guide 906 to be rotated, indexing device 950 automatically rotates the lateral jetting system directional guide through successive rotational steps according to the predetermined indexing sequence.

A method for jetting a wellbore with an automated jetting system will now be described with reference to the system of FIG. 9. Initially, the electronic controller of the indexing device 950 is pre-configured to cause the electro-mechanical drive to automatically rotate according to a predetermined indexing sequence that is desired for operation of the lateral jetting system 902. In one example, the indexing device is programmed uphole via the remote or local user interface to sequentially rotate the jetting directional guide 906 in alignment with respective circumferentially spaced ports 907 of the lateral jetting system casing through which lateral jetting is desired. Time intervals and lateral degree intervals between the rotations are programmed so that adequate time is provided between each incremental sequenced rotation of the directional guide by the indexing device to permit: 1) lateral insertion of a jetting hose, nozzle and assembly through the directional guide 906 and into the particular casing hole or opening 907 to which the directional guide has been aligned by the indexing device, 2) perform the required lateral jetting and extended reach stimulation operation, and 3) retract the lateral jetting hose, nozzle and assembly from the particular casing hole or opening 907 prior to the next index rotation of the lateral jetting system directional guide 906. Examples of such time and indexing angle intervals are illustrated in FIG. 10.

Once pre-programmed, the indexing device 950 is attached to the lateral jetting system for rotating the wellbore device. Indexing device 950 alternatively be attached to the lateral jetting system 902 prior to pre-programming. The indexing device program sequence is initiated and the lateral jetting system with the indexing device attached thereto inserted in the wellbore to an operating position downhole. An example of the indexing and jetting operations is as follows. The indexing device rotary actuator rotates the directional guide to a first jetting position in which the directional guide 906 is aligned with a first one of the lateral jetting holes/orifices 907. A jetting hose, nozzle and assembly is laterally inserted through the directional guide 906 and into the wellbore formation via the particular casing hole or opening 907 to which the directional guide has been aligned by the indexing device. Lateral jetting and extended reach stimulation operation, is then performed. The lateral jetting hose, nozzle and assembly are retracted from the particular casing hole or opening 907 prior to the next index rotation of the lateral jetting system directional guide 906 to a second jetting position in which the directional guide is aligned with a second one of the jetting orifices. Jetting is then performed via the second jetting orifice or opening. The indexing and jetting continues as necessary.

As illustrated by the aforementioned embodiments, the indexing device of one or more embodiments provides a more precise and smarter rotational function, accounting for such external downhole parameters such as rotation device stall, device stall recovery sequences and wellbore recovery of pressures and temperatures, before, during and after the operation.

Therefore, while the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this invention, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Other aspects of the invention will be apparent from the following description and the appended claims.