Patent Publication Number: US-10309174-B2

Title: Automated remote actuation system

Description:
BACKGROUND 
     Many tools deployed on coiled tubing for carrying out well interventions are designed to be ball activated. These tools are conveyed into a wellbore at the end of coiled tubing and are later activated while in the well. A ball of a predetermined size is placed inside the coiled tubing at a surface location and pumped down to the tool location via fluid flow. Once seated in place at the tool, circulation through the tool is interrupted. Additional pumping of fluid causes pressure above the ball to rise until sufficient force is created to activate the tool. The success of the process depends on the ability to place the ball properly downhole. However, proper placement of the ball can be compromised when cable is present inside the coiled tubing or when a large diameter pipe is used. Additionally, components above the ball-activated tool are often sized to allow free passage of the ball. Attempts have been made to release the ball from other locations, but such attempts have tended to rely on fluid flow which has limited adaptability for a variety of applications. 
     SUMMARY 
     In general, the present disclosure provides an actuation system used to actuate a tool, such as a downhole tool. The tool is actuated by an actuator element, e.g. a ball, which is selectively releasable from a remote location for interaction with the tool. A carrier is employed to hold the actuator element at the remote location until its desired release for interaction with the tool. The carrier may comprise an electro-mechanical actuator mechanism positioned to control release of the actuator element upon receipt of an appropriate control signal. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Certain embodiments will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements. It should be understood, however, that the accompanying figures illustrate only the various implementations described herein and are not meant to limit the scope of various technologies described herein, and: 
         FIG. 1  is a schematic illustration of an example of a well system comprising a tool and an actuation system for the tool, according to an embodiment of the disclosure; 
         FIG. 2  is a schematic illustration of an example of the actuation system, according to an embodiment of the disclosure; 
         FIG. 3  is a schematic illustration of another example of the actuation system, according to an alternate embodiment of the disclosure; 
         FIG. 4  is an illustration of an example of an actuatable tool combined with an actuation system, according to an embodiment of the disclosure; 
         FIG. 5  is an illustration similar to  FIG. 4  but showing another example of the tool and actuator system, according to an alternate embodiment of the disclosure; 
         FIG. 6  is an illustration of another example of the tool and actuator system, according to an alternate embodiment of the disclosure; 
         FIG. 7  is an illustration similar to  FIG. 6  but showing the system in a different state of actuation, according to an embodiment of the disclosure; and 
         FIG. 8  is an illustration similar to  FIG. 6  but showing the system in another state of actuation, according to an embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     In the following description, numerous details are set forth to provide an understanding of some illustrative embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible. 
     The disclosure herein generally relates to a system and methodology which enable remote actuation of tools. In well environments, for example, a downhole tool may be actuated by the remotely controlled release of an actuator element which drops via gravity and/or flows downstream to the tool to enable actuation of the tool. According to one embodiment, the actuator element is a ball selectively releasable from a downhole location for interaction with the tool. A carrier may be employed to hold the actuator element at the remote location until the tool is to be actuated. The carrier may comprise an electro-mechanical actuator mechanism which is operated via control signals sent from a remote, e.g. surface, location to control release of the actuator element. Once released, the actuator element moves downstream to the actuatable tool and lands in a corresponding seat. Application of pressure and the consequent creation of a pressure differential across the actuator element cause actuation of the tool. 
     The actuation system is configured such that there is no need to release a ball from the surface and to then pump it down along the wellbore to activate a tool. In some downhole applications the actuator system comprises a carrier with a single ball and in other applications the actuator system uses a plurality of balls or other actuator elements. The plurality of actuator elements may be released simultaneously or they may be individually released in a controlled manner. Release of the plurality of actuator elements is similarly controlled remotely from, for example, a surface location to enable movement of the actuator elements into engagement with corresponding downhole tools. In some applications, release of the ball or other type of actuator element is remotely controlled from the surface using a fixed signaling platform. 
     Referring generally to  FIG. 1 , an example of one type of application utilizing an actuation system combined with an actuatable tool is illustrated. The example is provided to facilitate explanation, and it should be understood that a variety of tools may utilize the actuation systems described herein. In many applications, the actuatable tools comprise downhole well tools although the actuation system may be used with other types of tools in other environments. 
     In  FIG. 1 , an embodiment of a well system  20  is illustrated as comprising downhole equipment  22 , e.g. a bottom hole assembly, deployed in a wellbore  24  on a tool string  26 . The bottom hole assembly  22  may be deployed downhole via a conveyance  28 , e.g. coiled tubing, forming part of tool string  26 . The bottom hole assembly  22  may include a wide variety of components, depending in part on the specific application, geological characteristics, and well type. In the example illustrated, the wellbore  24  is substantially vertical and lined with a casing  30 . Various bottom hole assemblies, well completions, and other embodiments of downhole equipment  22  may be used in a well system having many types of wellbores, including deviated, e.g. horizontal, single bore, multilateral, single zone, multi-zone, cased, uncased (open bore), or other types of wellbores. 
     In the example illustrated, bottom hole assembly  22  comprises an actuatable tool  32 , such as a valve, which may be actuated between different operational positions with the aid of an actuator element  34  selectively released from an actuation system  36 . By way of example, actuator element  34  may comprise a ball and actuation system  36  may comprise a ball drop system. The release of actuator element  34  is controlled from a remote location, such as a surface location, by a control system  38 . In some applications, the control system  38  comprises a fixed signaling platform. When tool  32  is to be actuated, the actuator element  34  is released by actuation system  36  upon receipt of an appropriate control signal from control system  38  via a communication line  40 . 
     Communication line  40  may comprise a variety of control lines capable of carrying control signals. For example, communication line  40  may comprise an optical fiber and/or an electrical conductor, e.g. a wire, routed downhole along tool string  26 . In some applications, the communication line  40  is disposed within coiled tubing  28 , e.g. within an interior of the coiled tubing such as a fiber optic tether comprising an outer protective tube encasing on or more optical fibers or the like, or within a wall of the coiled tubing. In other applications, the communication line  40  may be a wireless communication line by which wireless communication signals, e.g. electromagnetic, such as via WiMax communication, or acoustic signals, such as pulse communication or the like, are transmitted downhole via control system  38 . 
     Tool  32  and actuation system  36  may be used in a variety of well and non-well related applications in which the tools are positioned and actuated along a fluid flow path. In well applications, tool  32  may be designed for use in intervention operations and other well based operations. For example, tool  32  or a plurality of tools  32  can be used as active enablers for performing well remediation operations or to provide a contingency function upon the occurrence of an unplanned event or situation. The tool or tools  32  often are conveyed downhole in a dormant or passive state, and actuation system  36  is used to selectively actuate the desired tool  32  when, for example, a target depth is reached or when a certain condition occurs. Examples of tools  32  include disconnect tools, release joints, circulation valves, perforating firing heads, and other tools which may be actuated downhole. The tool  32  may comprise a tool permanently installed in the wellbore  24 , such as, but not limited to, an intelligent completion device such as a sand control screen or the like. 
     In a variety of applications, the actuator element  34  is selectively released from a location proximate tool  32  so the actuator element  34  is easily able to move into engagement with the tool  32 . The actuator element  34  also may comprise a ball or other element having a surface designed to readily engage a corresponding seat in tool  32 . Placement of the actuator element  34  across a corresponding sealing surface bridges the internal flow area of the tool and effectively arrests fluid circulation. Additional pumping of fluid down through tool string  26  creates a pressure differential across the actuator element  34  until sufficient force is created to actuate tool  32 . The force can be used to shift a variety of activating mechanisms within tool  32  depending on the type and design of the downhole tool. 
     Referring generally to  FIG. 2 , a schematic representation of an example of actuation system  36  and actuator element  34  is illustrated. It should be noted, however, the actuation system  36  and the actuator element  34  may be constructed in a variety of forms and configurations utilizing many types of carrier components, release components, actuator components, and other components selected according to the parameters of a given operation. In the example illustrated, actuation system  36  comprises an actuator housing  42  having a carrier  44  designed to carry an actuator element  34 , such as a ball, in an internal containment structure  45 . The actuator housing  42  also comprises a primary flow passage  46  which is part of the overall flow passage in tool string  26  which allows down flow of, for example, injection fluids and/or up flow of fluids, such as production fluids. 
     In the example illustrated, carrier  44  further comprises an electro-mechanical actuator mechanism  48 . The release of actuator element  34  from carrier  44  is controlled by electro-mechanical actuator mechanism  48 . According to one embodiment, the electro-mechanical actuator mechanism  48  comprises a solenoid  50  coupled to a release gate  52  which may be selectively moved to release the actuator element  34 . Release of the actuator element  34  allows the actuator element  34  to move into flow passage  46  and to flow downstream and into engagement with the corresponding tool  32 . Movement of the release gate  52  to the release position via solenoid  50  (or other suitable electro-mechanical actuator mechanism) is controlled remotely via control system  38  and control signals provided via communication line  40 . In this example, the actuator element  34  is released directly through actuation of the electro-mechanical actuation mechanism  48  at a location proximate tool  32 . 
     Electrical power may be provided to electromechanical actuator mechanism  48  via a suitable power source. For example, a downhole battery  54  may be used to supply power from a downhole location. In some applications, the battery  54  is a rechargeable battery which may be recharged by energy provided through communication line  40 . In other applications, a remote power source  56  may be used alone or in combination with battery  54  to supply power to the electro-mechanical actuator mechanism  48 . By way of example, the remote power source  56  may be located at the surface. 
     Referring generally to  FIG. 3 , another example of actuation system  36  is illustrated. In this embodiment, electro-mechanical actuation mechanism  48  is used to release a locking mechanism  58  which then enables release of the actuator element  34  via a secondary input. For example, electro-mechanical actuator mechanism  48  may again comprise a solenoid  50  coupled to locking mechanism  58  to enable removal/release of locking mechanism  58  upon receipt of an appropriate control signal via communication line  40 . The secondary input may be applied to a primary actuator  60  which is coupled to an actuator element release mechanism  62 , e.g. a ball release mechanism. 
     By way of example, primary actuator  60  may be actuated via fluid flow along flow passage  46 . Thus, once solenoid  50  is actuated to release locking mechanism  58 , a predetermined fluid flow may be pumped down through flow passage  46  to shift primary actuator  60 , thus removing release mechanism  62  from its position blocking release of actuator element  34 . In a specific example, fluid flow may be used to create a differential pressure across an orifice area to trigger release of the actuator element/ball  34 . The locking mechanism  58  prevents release of the ball  34  despite the presence of the differential pressure until the locking mechanism  58  is disabled or otherwise actuated by mechanism  48  to permit release of the ball  34 . In this manner, the inadvertent release of ball  34  due to fluid flow and/or differential pressure sensitivity is avoided. However, the use of fluid flow as the secondary input is provided only as an example. The primary actuator  60  may be designed for actuation upon other types of secondary inputs, e.g. input via a hydraulic control line, input via an electrical control line, input via a pressure signature, or inputs via other sources and techniques. 
     In well applications, the tool  32  and actuation system  36  are designed for deployment along wellbore  24  and are often tubular in form. In  FIG. 4 , an example of an arrangement of actuation system  36  and tool  32  is illustrated for use in a wellbore environment. In this example, the system components are generally tubular and comprise carrier  44  in the form of a ball carrier for carrying at least one ball  34 . Carrier  44  includes carrier structure  45  positioned between electro-mechanical actuation mechanism  48  and a receiver/controller  64 . The receiver/controller  64  is coupled to communication line  40  and is designed to receive and process control signals to instigate actuation of electro-mechanical actuator mechanism  48  upon receipt of the appropriate control signal. Upon actuation of mechanism  48 , ball  34  is either directly released or ready for release after the actuation system  36  receives an appropriate secondary input. When the ball  34  is released, the ball travels downstream to downhole tool  32  and engages a seat  66  of a shiftable component  68  within tool  32 . Fluid may then be pumped down through flow passage  46  to create a pressure differential across the ball  34  until shiftable component  68  is moved and tool  32  is transitioned to a different operational configuration. It should be noted that a variety of other compatible well string components may be connected above and below the actuation system  36 . 
     Referring generally to  FIG. 5 , a similar embodiment is illustrated. In this latter embodiment, however, the ball seat  66  is at a lower section of the tool string  26  and is not located immediately below the electro-mechanical actuator mechanism  48 , e.g. ball release mechanism. One or more additional tools or other components  70  may be positioned in the tool string between the ball release mechanism  45 ,  48  and the actuatable tool  32 . In this example, the internal diameters of each of the components  70  below carrier  44  and above the ball seat  66  are dimensioned to enable free passage of the ball or other type of actuator element  34 . 
     The embodiments illustrated in  FIGS. 4 and 5  are designed so that actuation system  36  can be made up to bottom hole assembly  22  above the tool  32 . In this example, the actuator element  34  remains in the retained position within carrier  44  during conveyance into wellbore  24 . When release of the actuator element  34  is desired, a control signal is sent downhole from the surface via communication line  40  which may be in the form of a wire or an optic fiber line inside the coiled tubing  28 . The actual release of actuator element  34  is achieved using solenoid  50  or another form of the electro-mechanical actuator  48 . As discussed above, the electro-mechanical actuator mechanism  48  can be powered from the surface and/or from a downhole battery. 
     Once released, the actuator element  34  may fall by gravity and land on seat  66  immediately below (or a short distance from) the carrier  44  and actuation system  36 . Fluid circulation through the bottom hole assembly  22  also may be used alone or in combination with gravity to cause the actuator element  34  to position correctly on seat  66 . Fluid flow can be helpful when wellbore  24  is drilled as a deviated, e.g. lateral, wellbore. Once the actuator element  34  is properly positioned, fluid circulation is stopped and differential pressure builds until the desired force is created to actuate tool  32 . The volume of fluid used to move actuator element  34  into position on seat  66  and to actuate tool  32  is relatively small because the distance over which the actuator element  34  is moved from its release point to tool  32  is relatively short. 
     Referring generally to  FIGS. 6-8 , another embodiment of the actuation system  36  and tool  32  is illustrated. In this embodiment, the actuation system  36  and its carrier  44  are sized to hold a plurality of actuator elements  34 , e.g. balls, as illustrated in  FIG. 6 . In some embodiments, the balls or other types of actuator elements  34  may be of the same size and may be released at the same time to activate a multi-ball activated tool  32 . In other applications, the actuator elements  34  may have progressively larger diameters and may be sequentially stacked in carrier  44  according to the progressively larger diameters to enable activation of a plurality of sequentially positioned tools  32  in the bottom hole assembly  22 . The actuator elements  34  are released by electro-mechanical actuator mechanism  48  individually, as illustrated in  FIG. 7 . 
     Each tool  32  of the plurality of sequentially positioned tools  32  comprises a shiftable component with a uniquely sized seat  66 . In some applications, the lowermost tool  32  uses the smallest diameter seat and the uppermost tool  32  uses the largest diameter seat to enable sequential actuation of the plurality of tools  32 . The initial actuator element  34  released from actuation system  36  may have a diameter selected to allow the actuator element to pass through the upper tools  32  (see  FIG. 8 ) and to sealingly engage the lowermost seat  66 . This enables actuation of the first tool  32  without affecting the other actuatable tools  32  positioned along the bottom hole assembly  22 . 
     When it is desired to actuate the next sequential tool, an appropriate control signal is again sent to electro-mechanical actuator mechanism  48  to again open the release gate  52  so as to release the next sequential actuator element  34 . This actuator element  34  then travels to the next sequential tool  32  and engages the corresponding seat  66 . Once the actuator element  34  is sealed against the corresponding seat  66 , the next sequential tool  32  may be actuated as described above. This process may be repeated for each of the actuator elements  34  and for each of the corresponding sequential tools  32 . 
     The specific configuration of tool or tools  32  may vary depending on the design of the overall tool string and on the parameters of a given application. Additionally, the actuation system  36  may have a variety of components arranged in several different types of configurations. The actuator element may comprise a ball element or another suitable actuator element, such as a dart. The electro-mechanical actuator mechanism also may have a variety of configurations, including various types of solenoids. However, the electro-mechanical actuator mechanism may comprise ball screws, linear motors, and other types of electro-mechanical actuators. Similarly, the electro-mechanical actuator mechanism may utilize many alternate types of release gates which may include platforms, cages, rods, ratchet mechanisms, pivot mechanisms, sliding mechanisms, and other types of mechanisms designed to accommodate release of actuator elements of various styles and sizes. 
     The actuation system and corresponding tool(s) may be used in many well related applications, such as well interventions. However, the remotely released actuator element also may be employed to release desired actuator elements in a variety of other well related applications. Similarly, the actuation system may be employed to selectively and remotely actuate tools in non-well applications, e.g. in surface pipeline applications or other applications in which tools are located downstream along a pipeline or conduit and actuated from a remote location. 
     The actuation system and corresponding tool(s) may comprise and/or provide two-way feedback communication (such as along the communication line  40 ) from various sensors on bottomhole assembly  22  and/or the downhole tool  32  including, but not limited to, pressure, temperature, vibration, sensors or the like, for providing real-time indication of downhole conditions to an operator of the well system  20 , as will be appreciated by those skilled in the art. 
     Although only a few embodiments of the system and methodology have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.