Abstract:
Devices and methods are provided for identifying changes in conditions in a downhole tool string or bottom hole assembly (BHA), which may be caused directly by manipulations or actions of the tool string or BHA. These devices and methods allow improved control and decision-making by an operator of the tool string or BHA, without the need to remove the tool string or BHA from a borehole, such as a wellbore. The device may be incorporated into a standalone unit or device that can be incorporated into any existing BHA to enhance operational efficiency, or it may be built as an integral portion of the tool or BHA component.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Provisional Patent Application 62/110,823, filed 2 Feb. 2015, the entirety of which is herein incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to devices and methods for extracting objects from a well, and in particular for indicating changes in the conditions of the well and/or a drill before, during, or after extraction of the object. 
       DESCRIPTION OF RELATED ART 
       [0003]    Work-over, object retrieval, and tool manipulation in boreholes, such as wellbores, can be exceedingly costly and time-consuming. One problem commonly encountered during drilling of, for example, an oil or gas wellbore is the breaking off or dropping of a piece of drill pipe, bit, other tool, or other item which must be retrieved from the wellbore (commonly referred to as a “fish”), which then falls to or is stuck at the bottom of the wellbore. A combination of a tool string and a bottom hole assembly (BHA), as is known in the art, may be lowered into the wellbore to retrieve the fish. 
         [0004]    The BHA typically has an external or internal catch device to engage the fish. Such catch devices are well-known to those of skill in the art and their use is widespread. However, it can be difficult to determine whether the fish has been successfully retrieved prior to retrieving the entire tool string and BHA from the borehole. This difficulty may prevent system operators from making more than one attempt to engage the fish with the BHA during each insertion of the tool string into the wellbore, and often requires operators to wait until the BHA is brought out of the wellbore to the surface before making key decisions. These uncertainties, in addition to the considerable time and costs expended in repeated insertion into, and retrieval from, the borehole of the tool string and BHA, expose operators to unnecessary delays and costs. 
         [0005]    Accordingly, there is a need in the art for devices and methods that allow the operator of a tool string/BHA combination to identify whether an object has been successfully retrieved from a borehole before the tool string/BHA combination is removed from the borehole to the surface. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention provides devices and methods that inform an operator of a tool string/BHA combination that one or more conditions have been met in a borehole, particularly at the site of the BHA. Devices according to the present invention are configured to energize, release stored energy, or create identifiable changes in operating parameters of the tool string when the downhole conditions are met. By way of non-limiting example, devices according to the present invention may be configured to completely restrict, partially restrict, or cause a pattern of fluctuations in the flow of a working fluid of the tool string. Any one or more of these and other indication methods can be utilized to confirm the change in conditions in the borehole. 
         [0007]    Embodiments of the present invention may comprise an indicator device that is included in the BHA and provides a method of detecting when a catch device, whether external or internal, has engaged and secured a fish or other object in the borehole. The device may be a standalone device that is installed above a standard recovery or fishing device as known in the art, or it may be an integral part of the BHA. The BHA may be lowered to an appropriate depth for engaging the fish, and then may be partially retrieved from the borehole. If the fish is engaged with the BHA, the added weight of the fish on the end of the tool string may energize the indicator device, which may activate a flow inhibiting component that inhibits the flow of a working fluid of the tool string. This inhibition can be registered by, for example, pressure gauges and flow rate gauges at the surface, providing an immediate indication to operators that the fish is engaged with the BHA. Significantly, because the indicator device is energized by the weight of the fish, the indicator device will remain energized whenever the fish is engaged, enabling operators to make timely interventions if the fish is inadvertently disengaged during retrieval of the tool string and BHA. Moreover, an operator can make multiple attempts to engage the fish if the indicator device indicates that the fish is not successfully engaged on the first attempt. 
         [0008]    The invention provides a device for indicating a change in an operating condition of a downhole tool string or bottom hole assembly (BHA), comprising a barrel, comprising a top end, the top end adapted to interconnect to the downhole tool string or BHA; a spring, adapted to interconnect to a downhole tool component and adapted to compress when the downhole tool component supports a weight of an object; a piston and a bushing, the piston interconnected to the spring and adapted to move along the bushing when the spring compresses, the bushing sealing the device and preventing the piston from being forced out of the device when the spring compresses; and a lid, interconnected to the piston and adapted to move from a first position to a second position when the piston moves along the bushing, wherein the lid substantially allows flow of a working fluid of the downhole tool string or BHA along a predetermined flow path when the lid is in the first position, and wherein the lid substantially restricts flow of the working fluid along the predetermined flow path when the lid is in the second position. 
         [0009]    In embodiments, the devices further comprises a lid housing, wherein at least a portion of the predetermined flow path runs through the lid housing, and wherein the lid seals against the lid housing when the lid is in the second position. 
         [0010]    In embodiments, the device further comprises a rupture disc, adapted to rupture and permit free flow of the working fluid when a pressure of the working fluid exceeds a predetermined limit. 
         [0011]    In embodiments, the lid is a drop door. 
         [0012]    In embodiments, the downhole tool component is an external catch device. 
         [0013]    In embodiments, the downhole tool component is an internal catch device. 
         [0014]    In embodiments, the lid is a flapper, a dual flapper, or a set of gates. 
         [0015]    The invention also provides a method for detecting whether a target object is secured to a downhole tool component of a work string, some embodiments of the method comprising a) providing an indicator device, comprising a barrel, comprising a top end, the top end interconnected to the work string; a spring, interconnected to a downhole tool component and adapted to compress when the downhole tool component supports a weight of the target object; a piston and a bushing, the piston interconnected to the spring and adapted to move along the bushing when the spring compresses, the bushing sealing the device and preventing the piston from being forced out of the device when the spring compresses; and a lid, interconnected to the piston and adapted to move from a first position to a second position when the piston moves along the bushing, wherein the lid substantially allows flow of a working fluid of the work string along a predetermined flow path through the lid housing when the lid is in the first position, and wherein the lid substantially restricts flow of the working fluid along the predetermined flow path when the lid is in the second position; b) lowering the downhole tool component into a borehole; c) positioning the downhole tool component into an engaging position relative to the target object; d) placing the work string in tension, whereby the downhole tool component supports the weight of the target object; e) initiating flow of the working fluid along the flow path; and f) measuring a pressure of the working fluid. 
         [0016]    In embodiments, the indication device further comprises a lid housing, wherein at least a portion of the predetermined flow path runs through the lid housing, and wherein the lid seals against the lid housing when the lid is in the second position. 
         [0017]    In embodiments, the indication device further comprises a rupture disc, adapted to rupture and permit free flow of the working fluid when a pressure of the working fluid exceeds a predetermined limit. 
         [0018]    In embodiments, the lid of the indication device is a drop door. 
         [0019]    In embodiments, the downhole tool component is an external catch device. 
         [0020]    In embodiments, the downhole tool component is an internal catch device. 
         [0021]    In embodiments, the method further comprises, between steps c) and d), pulling or jarring loose the target object. 
         [0022]    The invention further provides a system for detecting a change in an operating condition of a downhole tool string or bottom hole assembly (BHA), comprising an indication device, comprising a barrel, comprising a top end, the top end adapted to interconnect to the downhole tool string or BHA; a spring, interconnected to a downhole tool component and adapted to compress when the downhole tool component supports a weight of an object; a piston and a bushing, the piston interconnected to the spring and adapted to move along the bushing when the spring compresses, the bushing sealing the device and preventing the piston from being forced out of the device when the spring compresses; and a lid, interconnected to the piston and adapted to move from a first position to a second position when the piston moves along the bushing, wherein the lid substantially allows flow of a working fluid of the downhole tool string or BHA along a predetermined flow path when the lid is in the first position, and wherein the lid substantially restricts flow of the working fluid along the predetermined flow path when the lid is in the second position; a pump, pumping the working fluid along the flow path; and a pressure gauge, measuring a pressure of the working fluid at the flow restriction point. 
         [0023]    In embodiments, the system further comprises a lid housing, wherein at least a portion of the predetermined flow path runs through the lid housing, and wherein the lid seals against the lid housing when the lid is in the second position. 
         [0024]    In embodiments, the system further comprises a rupture disc, adapted to rupture and permit free flow of the working fluid when a pressure of the working fluid exceeds a predetermined limit. 
         [0025]    In embodiments, the lid is a drop door. 
         [0026]    In embodiments, the downhole tool component is an external catch device. 
         [0027]    In embodiments, the downhole tool component is an internal catch device. 
         [0028]    For purposes of further written description and enablement of the various embodiments of the present invention, the following are herein incorporated by reference in their entireties: 
         [0029]    U.S. Pat. No. 6,619,388, entitled “Fail safe surface controlled subsurface safety valve for use in a well,” issued 16 Sep. 2003 to Dietz et al. 
         [0030]    U.S. Pat. No. 7,246,663, entitled “Positive engagement indicator for wireline fishing operations,” issued 24 Jul. 2007 to Rose. 
         [0031]    U.S. Pat. No. 7,591,314, entitled “Measurement-while-fishing tool devices and methods,” issued 22 Sep. 2009 to Sonnier et al. 
         [0032]    U.S. Patent Application Publication 2011/0155381, entitled “Surface controlled subsurface safety valve assembly with primary and secondary valves,” published 30 Jun. 2011 to Reaux. 
         [0033]    U.S. Pat. No. 8,353,353, entitled “Surface controlled subsurface safety valve assembly with primary and secondary valves,” issued 15 Jan. 2013 to Reaux. 
         [0034]    U.S. Pat. No. 8,733,438, entitled “System and method for obtaining load measurements in a wellbore,” issued 27 May 2014 to Kenison et al. 
         [0035]    While this description is directed primarily toward the solution of problems inherent to hydrocarbon wells, those of ordinary skill in the art will understand that the solutions of the present invention are equally applicable to gas or water injections, water wells, and any other borehole operation or pipeline activity, and that the scope of the present invention encompasses such applications. 
         [0036]    These and other advantages will be apparent from the disclosure of the invention(s) contained herein. The above-described embodiments, objectives, and configurations are neither complete nor exhaustive. The Summary of the Invention is neither intended nor should it be construed as being representative of the full extent and scope of the present invention. Moreover, references made herein to “the present invention” or aspects thereof should be understood to mean certain embodiments of the present invention and should not necessarily be construed as limiting all embodiments to a particular description. The present invention is set forth in various levels of detail in the Summary of the Invention as well as in the attached drawings and Detailed Description and no limitation as to the scope of the present invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the present invention will become more readily apparent from the Detailed Description particularly when taken together with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0037]    The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the disclosure and together with the general description of the disclosure given above and the detailed description of the drawings given below, serve to explain the principles of the disclosures. 
           [0038]      FIG. 1  is an exploded front view of an indicator device, according to embodiments of the present invention; 
           [0039]      FIG. 2  is a cross-sectional view of an indicator device, according to embodiments of the present invention; 
           [0040]      FIG. 3  is a cross-sectional view of a burst disc of an indicator device, according to embodiments of the present invention; 
           [0041]      FIG. 4  is a cross-sectional view of an indicator device with a drop door in a first state, according to embodiments of the present invention; 
           [0042]      FIG. 5  is a cross-sectional view of an indicator device with a drop door in a second state, according to embodiments of the present invention; 
           [0043]      FIG. 6  is a cross-sectional view of an indicator device with a drop door in a second state, according to embodiments of the present invention; 
           [0044]      FIG. 7  is a cross-sectional view of an indicator device with a drop door in a second state, according to embodiments of the present invention; 
           [0045]      FIG. 8  is a cross-sectional view of an indicator device with a drop door in a second state, according to embodiments of the present invention; 
           [0046]      FIG. 9  is a perspective view of an indicator device, according to embodiments of the present invention; 
           [0047]      FIG. 10  is a perspective view of an indicator device, according to embodiments of the present invention; 
           [0048]      FIG. 11  is a perspective view of an indicator device, according to embodiments of the present invention; 
           [0049]      FIG. 12  is a perspective view of an indicator device, according to embodiments of the present invention; 
           [0050]      FIG. 13  is a cross-sectional view of an indicator device with a drop door in a first state, according to embodiments of the present invention; and 
           [0051]      FIG. 14  is an illustration of a method for detecting changes in a downhole tool string or bottom hole assembly, according to embodiments of the present invention. 
           [0052]    It should be understood that the drawings are not necessarily to scale, and various dimensions may be altered. In certain instances, details that are not necessary for an understanding of the invention or that render other details difficult to perceive may be omitted. It should be understood that the invention is not necessarily limited to the particular embodiments illustrated herein. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0053]    The present invention has significant benefits across a broad spectrum of endeavors. It is the Applicant&#39;s intent that this specification and the claims appended hereto be accorded a breadth in keeping with the scope and spirit of the invention being disclosed despite what might appear to be limiting language imposed by the requirements of referring to the specific examples disclosed. To acquaint persons skilled in the pertinent arts most closely related to the present invention, a preferred embodiment is described herein by, and with reference to, the annexed drawings that form a part of the specification. The exemplary embodiment is described in detail without attempting to describe all of the various forms and modifications in which the invention might be embodied. As such, the embodiments described herein are illustrative, and as will become apparent to those skilled in the arts, and may be modified in numerous ways within the scope and spirit of the invention. 
         [0054]    Although the following text sets forth a detailed description of numerous different embodiments, it should be understood that the detailed description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims. To the extent that any term recited in the claims at the end of this patent is referred to in this patent in a manner consistent with a single meaning, that is done for sake of clarity only so as to not confuse the reader, and it is not intended that such claim term by limited, by implication or otherwise, to that single meaning. 
         [0055]    Various embodiments of the present invention are described herein and as depicted in the drawings. It is expressly understood that although the figures depict bottom hole assemblies, indicator subs, drop doors, and burst discs, the present invention is not limited to these embodiments. 
         [0056]    Referring now to  FIG. 1 , an indication device  100  according to embodiments of the present invention comprises a piston assembly  110 , a barrel  120 , a bushing  130 , and a lid  140 . The particular device illustrated in  FIG. 1  further comprises a lid housing  150 . The piston assembly comprises a piston component  111  and a spring component  112 . The barrel  120  comprises a top end  121  that is adapted to interconnect to a downhole tool string or BHA. The spring component  112  is adapted to interconnect to a downhole tool component and compress when the downhole tool component supports a weight of an object. The piston component  111  is interconnected to the spring component  112  and is adapted to move along the bushing  130  when the spring component  112  compresses. The bushing  130  seals the device  100  and prevents the piston component  111  from being forced out of the device  100  when the spring component  112  compresses. The lid  140  is interconnected to the piston component  111  and is adapted to move from a first position to a second position as the piston component  111  moves along the bushing  130 . When the lid  140  is in the first position, the lid  140  substantially allows flow of a working fluid of the downhole tool string or BHA along a predetermined flow path; when the lid  140  is in the second position, the lid  140  substantially restricts flow of the working fluid along the predetermined flow path. The lid may, but need not, be adjacent a lid housing  150  when the lid  140  is in the second position. In such embodiments, at least part of the predetermined flow path may flow through the lid housing  150 , such that flow of the working fluid through the lid housing  150  is prevented when the lid  140  is in the second position.  FIGS. 9 and 10  provide further illustrations of a device  100  in an assembled state, and  FIGS. 11 and 12  provide further illustrations of a device  100  in an exploded state. 
         [0057]    The device  100  illustrated in  FIG. 1  may be used as part of a novel method for detecting whether a target object is secured to the downhole tool component. By way of non-limiting example, the tool component, after interconnection to the device  100 , may be lowered into a borehole and then positioned in an engaging position relative to the target object. An operator may then place the work string in tension such that the downhole tool component supports the weight of the target object, initiate flow of the working fluid along the flow path, and measure a pressure of the working fluid. The position of the lid  140 , and thus the pressure of the working fluid along the predetermined flow path, will be determined by whether the target object is engaged with the downhole tool component. 
         [0058]    Referring now to  FIGS. 2 and 3 , a device  100  according to embodiments of the present invention may further comprise a rupture disc  160 . In the embodiment illustrated in  FIGS. 2 and 3 , the lid  140  takes the form of a drop door. The rupture disc  160  is a non-reclosing pressure relief device that protects the other components of the device  100  from damage in case the pressure of the working fluid rises too quickly. The lid  140  may protect the rupture disc  160  prior to engagement between the target object and the downhole tool component, then expose the rupture disc  160  to the pressure of the working fluid after engagement. The lid  140  in  FIG. 3  is in a first state, wherein the drop door is oriented longitudinally relative to the device  100 . Once the target object is secured and the work string is placed in tension, as in  FIG. 2 , the movement of the piston component  111  due to the weight of the target object urges the lid  140  into a second state, wherein the drop door is generally oriented laterally relative to the device  100  and prevents fluid flow through the device  100 . An operator at the surface may therefore pump the working fluid along the predetermined flow path and, by measuring the pressure of the working fluid, determine whether fluid flow is permitted (first state,  FIG. 2 ) or prevented (second state,  FIG. 3 ), and thus whether the target object has been secured.  FIG. 4  provides another illustration of a device  100  with a lid  140  in the form of a drop door in the first state, and  FIGS. 5-8 and 13  provide further illustrations of a device  100  with a lid  140  in the form of a drop door in the second state. 
         [0059]    Referring now to  FIG. 14 , some embodiments of the method  1400  for detecting whether a target object is secured to a downhole tool component of a work string comprise a lowering step  1410 , a positioning step  1420 , a placing step  1440 , an initiating step  1450 , and a measuring step  1460 . In the lowering step  1410 , A downhole tool component is lowered into a borehole. In the positioning step  1420 , the downhole tool component is positioned into an engaging position relative to a target object. In placing step  1440 , the work string is placed in tension such that the downhole tool component supports the weight of the target object if the target object is secured to the downhole tool component. In initiating step  1450 , flow of a working fluid along a predetermined flow path is initiated. In measuring step  1460 , a pressure of the working fluid is measured. In some embodiments, the method may further comprise a pulling or jarring step  1430 , in which the target object is stuck and is pulled or jarred loose. The method of the present invention is not limited to either the order of steps set forth in  FIG. 14  or the steps set forth in  FIG. 14 , and persons skilled in the art will appreciate that the method of the present invention may be performed using different steps or the steps set forth herein in different orders. 
         [0060]    The present invention has significant benefits across a broad spectrum of endeavors. It is the Applicant&#39;s intent that this specification and the claims appended hereto be accorded a breadth in keeping with the scope and spirit of the invention being disclosed despite what might appear to be limiting language imposed by the requirements of referring to the specific examples disclosed. 
         [0061]    The phrases “at least one”, “one or more”, and “and/or”, as used herein, are open-ended expressions that are both conjunctive and disjunctive in operation. For example, each of the expressions “at least one of A, B, and C”, “at least one of A, B, or C”, “one or more of A, B, and C”, “one or more of A, B, or C,” and “A, B, and/or C” means A alone, B alone, C alone, A and B together, A and C together, B and C together, or A, B, and C together. 
         [0062]    Unless otherwise indicated, all numbers expressing quantities, dimensions, conditions, and so forth used in the specification, drawings, and claims are to be understood as being modified in all instances by the term “about.” 
         [0063]    The term “a” or “an” entity, as used herein, refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. 
         [0064]    The use of “including,” “comprising,” or “having,” and variations thereof, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Accordingly, the terms “including,” “comprising,” or “having” and variations thereof can be used interchangeably herein. 
         [0065]    It shall be understood that the term “means” as used herein shall be given its broadest possible interpretation in accordance with 35 U.S.C., Section 112(f). Accordingly, a claim incorporating the term “means” shall cover all structures, materials, or acts set forth herein, and all of the equivalents thereof. Further, the structures, materials, or acts, and the equivalents thereof, shall include all those described in the summary of the invention, brief description of the drawings, detailed description, abstract, and claims themselves. 
         [0066]    The foregoing description of the present invention has been presented for illustration and description purposes. However, the description is not intended to limit the invention to only the forms disclosed herein. In the foregoing Detailed Description for example, various features of the invention are grouped together in one or more embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description, with each claim standing on its own as a separate preferred embodiment of the invention. 
         [0067]    Consequently, variations and modifications commensurate with the above teachings and skill and knowledge of the relevant art are within the scope of the present invention. The embodiments described herein above are further intended to explain best modes of practicing the invention and to enable others skilled in the art to utilize the invention in such a manner, or include other embodiments with various modifications as required by the particular application(s) or use(s) of the present invention. Thus, it is intended that the claims be construed to include alternative embodiments to the extent permitted by the prior art.