Patent Document

CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Patent Application Ser. No. 62/350,284 filed Jun. 15, 2016, which is incorporated herein in its entirety by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates to an apparatus and methods for allowing isolation of a well during multiple phases of drilling and completions. 
       BACKGROUND OF THE INVENTION 
       [0003]    In the oil and gas industry, wellbores are drilled into the earth using drilling rigs, where tubulars are threaded together to form long tubular strings that are inserted into the wellbore to extract the desired fluid. Exposure of various rock types and corresponding pressures during drilling and most commonly, post fracturing and acidizing stimulation work, requires a means for isolating the formation downhole by means of closing a valve or sealing off so that wellhead pressure can be bled off for building an alternative tool string uphole of any desired length and lowering that tool string downhole without a need for snubbing under wellhead pressure for the purpose of performing wellbore operations downhole during a single trip into the wellbore or to manipulate fluid type and properties without risk of the exposed formation below the seal affecting the ability to control the well above the seal. 
         [0004]    To achieve this, valves are used that open and close to isolate and then expose the formation below and the subsequent hydrocarbon. In addition, many operators utilize existing technologies that require the use of rotation, reciprocation, nitrogen, or restrict operability in subsequent operations after closure. 
         [0005]    What is needed, therefore, is a means to provide a simple mechanical seal that integrates into any string configuration, capable of sealing from above and below with the ability for the seal to be disposed of or retrieved with existing technology. 
       SUMMARY OF THE INVENTION 
       [0006]    The invention would provide an additional barrier between reservoirs or pressured zones and the surface and allowing for isolation of pressure from below and fluid loss from above, thus meeting a multiple barrier guideline often required by operator policy and governmental regulatory requirements. In particular, but not exclusively, the invention relates to a tool for, and a method of, isolating formation pressure from exiting the well and drilling or completion fluid from entering the same zones when activated while permitting an ability to jettison the sealing element at a later time when desired. This invention is applicable to well construction operations, gravel packing and fracturing operations, or may be used as a temporary suspension barrier. 
         [0007]    It is therefore an aspect of embodiments of the invention to provide an isolating tool capable of preventing wellbore fluids from exiting the well and drilling and completion fluids from being lost to the well without the requirement of multiple runs, special tools, unique fluid systems such as nitrogen, or the like. 
         [0008]    It is one aspect of embodiments of the invention to give the ability to integrate into stimulation tools and techniques and permit implementation of a seal with washpipe or similar and disposal with mechanical force or pressure. 
         [0009]    It is another aspect of embodiments of the invention to give the ability for optional implementation prior to a decision to use and provide the ability to utilize in well construction for contingency operations such as during severe weather. 
         [0010]    It is another aspect of embodiments of the invention to provide a means of installing the seal from both, either, or the bottom or top. 
         [0011]    It is yet another aspect of embodiments of the invention to provide an apparatus that may be capable of holding pressure from above and an equivalent or higher pressure from below. 
         [0012]    It is another aspect of embodiments of the invention to provide an apparatus that may be capable of being inserted into multiple size tubulars. 
         [0013]    It is another aspect of embodiments of the invention to provide an apparatus that will provide pressure integrity above and below after installation and thus qualify as a barrier. 
         [0014]    It is another aspect of embodiments of the invention to provide an apparatus in which the seal may be jettisoned with pressure or force. 
         [0015]    It is another aspect of embodiments of the invention to provide an apparatus in which the jettisoned seal and/or the seal sub would be capable of retrieval or being milled. 
         [0016]    One particular embodiment of the present invention is a method for isolating a wellbore, comprising (i) providing a seal sub, a grapple assembly coupled to the seal sub via a shear screw, a washpipe, a ball setting tool and a seal ball, wherein the ball setting tool is coupled to one end of the washpipe, and wherein the seal ball is coupled to the ball setting tool; (ii) pulling the washpipe through the interior volume of the seal sub such that a grapple catch of the seal ball contacts a ball catch lip of the seal sub; and (iii) pulling the washpipe, after the contact between the grapple catch and the ball catch lip, through an interior volume of the seal sub with a sufficient force to shear the shear screw, which causes the grapple assembly to decouple from the seal sub. 
         [0017]    In some embodiments, the method can further comprise (iv) providing a shear screw between the seal ball and the ball setting tool; (v) pulling the washpipe through the interior volume of the seal sub such that the seal ball selectively connects to a ball seat of the seal sub; and (vi) pulling the washpipe through the interior volume of the seal sub with a sufficient force to shear the shear screw of the seal ball-ball setting tool connection, which causes the ball setting tool to decouple from the seal ball. In various embodiments, the sufficient force to shear the shear screw of the seal ball-ball setting tool connection is larger than the sufficient force to shear the shear screw of the grapple assembly-seal sub connection. In some embodiments, the method can further comprise (vii) applying an uphole pressure to dislodge the selective connection between the seal ball and the ball seat and allow the seal ball to travel downhole. 
         [0018]    In various embodiments, the method can further comprise (viii) providing at least one grapple spring on the grapple assembly, the at least one grapple spring is configured to retain the dislodged seal ball and prevent the seal ball from travelling further downhole. In some embodiments, the method can further comprise (ix) providing a catch sub positioned downhole of the seal sub, the catch sub having a primary channel extending through the catch sub, a ball catch lever movable between a first and a second position, and a receiving volume in fluid communication with the primary channel; (x) directing, by the ball catch lever in the first position, the dislodged seal ball from the primary channel to the receiving volume; (xi) moving, by the seal ball, the ball catch lever from the first position to the second position; and (xii) retaining, by the ball catch lever in the second position, the seal ball in the receiving volume. In various embodiments, the method can further comprise (xiii) providing a bypass sub uphole of the seal sub, the bypass sub having a primary channel and a bypass line, wherein the bypass line is in fluid communication with the primary channel at a first and a second location along a longitudinal length of the primary channel; and (xiv) transferring a pressure increase from the first position, through the bypass line, and to the second position located downhole of the first position. 
         [0019]    Another particular embodiment of the present invention is a system for isolating a wellbore, comprising a setting tool having an upper end, a lower end, and an outer diameter; a seal ball having an upper end, a lower end, and a gripping feature disposed around at least a portion of an outer circumference of the seal ball; a shear pin selectively connecting the lower end of the setting tool to the upper end of the seal ball, wherein the shear pin is configured to break in response to a predetermined force; a seal sub having a ball seat and a gripping feature, wherein at least a portion of the ball seat has an inner diameter that is larger than the outer diameter of the setting tool and that is smaller than an outer diameter of the gripping feature of the seal ball; and wherein as the setting tool passes through the ball seat, the seal ball contacts the ball seat of the seal sub, and the gripping feature of the seal ball selectively connects with the gripping feature of the seal sub, and wherein the predetermined force is applied to the setting tool and the shear pin to break the shear pin and leave the seal ball selectively connected to the seal sub. 
         [0020]    In various embodiments, the gripping feature of the seal ball is a plurality of ribs that continuously extend around the outer circumference of the seal ball. In some embodiments, the seal sub further comprises a seal assembly that has the ball seat; and a seal retaining nut assembly that maintains the seal assembly and the ball seat in a predetermined longitudinal position in the seal sub. In various embodiments, the seal sub further comprises a grapple assembly that has the gripping feature, which is a ball catch lip, and the grapple assembly is selectively connected to an inner surface of a body of the seal sub via a shear pin, wherein the shear pin of the grapple assembly-body connection is configured to break in response to a predetermined force that is less than the predetermined force required to break the shear pin of the setting tool-seal ball connection. 
         [0021]    In some embodiments, as the setting tool passes through the ball seat, the shear pin of the grapple assembly-body connection breaks and the grapple assembly moves from a first position to a second position where a shear ring selectively connects the grapple assembly to the body of the shear sub, and the grapple assembly maintains the seal ball against the ball seat. In various embodiments, the selective connection between the seal ball and the seal sub is configured to release in response to a pressure from an upper end of the well and a pressure from a lower end of the well, wherein the pressure from the upper end of the well is less than the pressure from the lower end of the well. In some embodiments, the grapple assembly further comprises at least one grapple spring positioned downhole of the ball seat and the gripping feature, wherein the at least one grapple spring is configured to retain the seal ball after the seal ball is dislodged from the ball seat and the gripping feature in response to a pressure from an upper end of the well. 
         [0022]    In various embodiments, the system further comprises a ball catch sub positioned downhole of the seal sub, the ball catch sub comprising a primary channel, a ball catch lever, and a receiving volume that is in fluid communication with the primary channel; wherein in a first position the ball catch lever extends into the primary channel to direct the seal ball into the receiving volume; and wherein in a second position the ball catch lever is oriented substantially parallel to a longitudinal axis of the primary channel to contain the seal ball in the receiving volume. In some embodiments, the system further comprises a bypass sub positioned uphole of the seal sub, the bypass sub having a primary channel and a bypass line in fluid communication with the primary channel, wherein the bypass line extends from a first position to a second position along a longitudinal length of the primary channel to allow a pressure increase at the first position to transfer to the second position. 
         [0023]    Yet another particular embodiment of the present invention is a system for isolating a wellbore, comprising a seal sub having an inner surface with an inner diameter and a lip forming a recess in the inner surface; a grapple assembly having an outer surface with an outer diameter and a collet extending outward from the outer surface, and the grapple assembly having an inner surface with a ball seat; a seal ball positioned adjacent the ball seat, and the seal ball selectively connected to the inner surface of the grapple assembly with at least one shear pin that is configured to break when subjected to a predetermined force; and wherein as the grapple assembly travels uphole, the inner surface of the seal sub deflects the collet inwards until the collet reaches the lip and deflects outward into the recess in the inner surface to secure the relative position of the seal sub and the grapple assembly. 
         [0024]    In some embodiments, the system further comprises a pressure port through the seal sub at a location uphole of the ball seat, wherein the pressure port is in fluid communication with a downhole pressure such that the downhole pressure drives the ball seat into the seal ball; and a piston positioned in the seal sub at a location uphole of the ball seat, and the piston is operatively connected to the ball seat, wherein an uphole pressure causes the piston to drive the ball seat into the seal ball. In various embodiments, the system further comprises a bonded seal positioned on the outer surface of the grapple assembly such that the bonded seal forms a seal between the outer surface of the grapple assembly and the inner surface of the seal sub to isolate, in conjunction with the seal ball, an uphole pressure from a downhole pressure. In some embodiments, the system further comprises a wash pipe selectively connected to an upper end of the grapple assembly. 
         [0025]    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 invention. Moreover, references made herein to “the invention” or aspects thereof should be understood to mean certain embodiments of the invention and should not necessarily be construed as limiting all embodiments to a particular description. The 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 invention is intended by either the inclusion or non-inclusion of elements, components, etc. in this Summary of the Invention. Additional aspects of the invention will become more readily apparent from the Detailed Description particularly when taken together with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0026]    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. 
           [0027]      FIG. 1  is a cross-sectional view of a seal sub according to one embodiment of the invention; 
           [0028]      FIG. 2  is a cross-sectional view of a seal sub sealed by a seal ball according to one embodiment of the invention; 
           [0029]      FIG. 3  is a cross-sectional view of a sealing portion of a seal sub according to one embodiment of the invention; 
           [0030]      FIG. 4A  is a side elevation view of a seal ball according to one embodiment of the invention; 
           [0031]      FIG. 4B  is a perspective view of a seal ball according to one embodiment of the invention; 
           [0032]      FIG. 4C  is a cross-sectional view of a seal ball according to one embodiment of the invention; 
           [0033]      FIG. 4D  is a top plan view of a seal ball according to one embodiment of the invention; 
           [0034]      FIG. 5A  is a side elevation view of a ball setting tool according to one embodiment of the invention; 
           [0035]      FIG. 5B  is a cross-sectional view of a ball setting tool according to one embodiment of the invention; 
           [0036]      FIG. 5C  is a perspective view of a ball setting tool according to one embodiment of the invention; 
           [0037]      FIG. 6A  is a side elevation view of a seal sub according to an alternative embodiment of the invention; 
           [0038]      FIG. 6B  is a cross-sectional view of a seal sub according to an alternative embodiment of the invention; 
           [0039]      FIG. 6C  is a perspective view of a seal sub according to an alternative embodiment of the invention; 
           [0040]      FIG. 7A  is a side elevation view of a seal retaining nut assembly according to an alternative embodiment of the invention; 
           [0041]      FIG. 7B  is a cross-sectional view of a seal retaining nut assembly according to an alternative embodiment of the invention; 
           [0042]      FIG. 7C  is a perspective view of a seal retaining nut assembly according to an alternative embodiment of the invention; 
           [0043]      FIG. 8A  is a side elevation view of a seal ball according to an alternative embodiment of the invention; 
           [0044]      FIG. 8B  is a cross-sectional view of a seal ball according to an alternative embodiment of the invention; 
           [0045]      FIG. 8C  is a perspective view of a seal ball according to an alternative embodiment of the invention; 
           [0046]      FIG. 9A  is a side elevation view of a seal assembly according to an alternative embodiment of the invention; 
           [0047]      FIG. 9B  is a cross-sectional view of a seal assembly according to an alternative embodiment of the invention; 
           [0048]      FIG. 9C  is a perspective view of a seal assembly according to an alternative embodiment of the invention; 
           [0049]      FIG. 10A  is a side elevation view of a grapple assembly according to an alternative embodiment of the invention; 
           [0050]      FIG. 10B  is a cross-sectional view of a grapple assembly according to an alternative embodiment of the invention; 
           [0051]      FIG. 10C  is a perspective view of a grapple assembly according to an alternative embodiment of the invention; 
           [0052]      FIG. 11A  is a side elevation view of a grapple stop sleeve according to an alternative embodiment of the invention; 
           [0053]      FIG. 11B  is a cross-sectional view of a grapple stop sleeve according to an alternative embodiment of the invention; 
           [0054]      FIG. 11C  is a perspective view of a grapple stop sleeve according to an alternative embodiment of the invention; 
           [0055]      FIG. 12A  is a side elevation view of a seal sub sealed by a seal ball according to an alternative embodiment of the invention; 
           [0056]      FIG. 12B  is a cross-sectional view of a seal sub sealed by a seal ball according to an alternative embodiment of the invention; 
           [0057]      FIG. 12C  is a perspective view of a seal sub sealed by a seal ball according to an alternative embodiment of the invention; 
           [0058]      FIG. 13  is a cross-sectional view of a seal sub sealed by a ball according to yet another alternative embodiment of the invention; 
           [0059]      FIG. 14A  is a cross-sectional view of a ball catch sub with a lever in a first position according to an embodiment of the invention; 
           [0060]      FIG. 14B  is a cross-sectional view of a ball catch sub with a lever in a second position according to an embodiment of the invention; and 
           [0061]      FIG. 15  is a cross-sectional view of a bypass sub according to an embodiment of the invention. 
       
    
    
       [0062]    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 have been omitted. It should be understood, of course, that the invention is not necessarily limited to the particular embodiments illustrated herein. 
       DETAILED DESCRIPTION 
       [0063]    The 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 invention, a preferred embodiment that illustrates the best mode now contemplated for putting the invention into practice 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. 
         [0064]    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. Terms such as “shear pin” and “shear screw” can be used interchangeably and generally refer to any device that breaks in response to a predetermined force. 
         [0065]    In a preferred embodiment, the Jettison Able Ball Seal (JABS) is comprised of a seal sub and a seal ball. 
         [0066]    Now referring to  FIG. 1 , a cross-sectional view of seal sub  100  of a preferred embodiment is provided. The body of seal sub  100  is cylindrical, with the exterior surface of seal sub  100  being disposed about central axis  104  and having a uniform outer diameter. Seal sub  100  is comprised of an upper portion  112  and a lower portion  108 . Upper portion  112  is comprised of an opening disposed about central axis  104  at the top end, and tapered portion  120  at the bottom end. Lower portion  108  is comprised of an opening disposed about central axis  104  at the bottom end, and tapered portion  124  at the top end. A sealing portion  116  is disposed between tapered portions  120  and  124 . In some embodiments, the internal diameter of upper portion  112  and lower portion  108  will be identical, whereas in other embodiments the internal diameter of upper end  112  and lower end  108  will be different. 
         [0067]    Now referring to  FIG. 2 , a cross-sectional view of seal sub  100  sealed by seal ball  204  of a preferred embodiment is provided. Seal ball  204  is detailed further below. 
         [0068]    Now referring to  FIG. 3 , a cross-sectional view of sealing portion  116  of a preferred embodiment is provided. Sealing portion  116  is comprised of ball receiving channel  304 , gripping feature  308 , ball seat  312 , and sealable channel  316 . Ball receiving channel  304  has an internal diameter sufficiently larger than the diameter of seal ball  204  to enable the seal ball to pass through the ball receiving channel  304 . In a preferred embodiment, gripping feature  308  may be comprised of a plurality of grooves, such as those disclosed by International Application No. PCT/US16/16368, which is incorporated herein by reference. Ball seat  312  has an internal diameter that is sufficiently smaller than the diameter of seal ball  204  to prevent passage of the seal ball through sealable channel  316 . 
         [0069]    Now referring to  FIGS. 4A-4D , several views of seal ball  204  of a preferred embodiment are provided. In the preferred embodiment, seal ball  204  is spherical, however it will be appreciated by one skilled in the art that a seal ball  204  of other shapes may be used to practice the invention disclosed herein, such as ovoidal or conical on one end. Gripping feature  404  is disposed about the equator of seal ball  204 . A bonded seal area  408  is located on the upper portion of the upper hemisphere of seal ball  204 , comprising a plurality of concentric circular bonded seals. It will be appreciated that the bonded seal area  408  may cover a different portion of seal ball  204  in different embodiments. For example, bonded seal area  408  may cover the entire upper hemisphere of seal ball  204  in some embodiments, while in other embodiments the bonded seal area may comprise a single circular ridge. Seal ball  204  is further comprised of shear pin  412 , which is threaded into an opening at the top of seal ball  204 . In other embodiments, shear pin  412  may be comprised of any material known in the art that will shear under a predetermined amount of force. In a preferred embodiment, with the exception of shear pin  412 , seal ball  204  is comprised of a single piece of material. 
         [0070]    Now referring to  FIGS. 5A-5C , several views of ball setting tool  500  of a preferred embodiment are provided. In the preferred embodiment, ball setting tool  500  is cylindrical and has an outer diameter that is less than the inner diameter of sealable channel  316 . Seal ball connection point  504  is situated on the lower end of ball setting tool  500 . Seal ball connection point  504  is comprised of a concave depression of substantially similar curvature of seal ball  204 . Seal ball connection point  504  is further comprised of a cylindrical cavity capable of receiving shear pin shear pin  412 . In some embodiments of the present invention, ball setting tool  500  may further be comprised of a plurality of debris wash ports  508  which allow for an operator to run fluid downhole to wash debris off seal ball  204  or from sealing portion  116  as desired. Washpipe connection point  512  is situated on the lower end of ball setting tool  500 . 
         [0071]    In a preferred embodiment, seal sub  100  is manufactured from a single piece of material, such that upper portion  112 , lower portion  108 , sealing portion  116 , and tapered portions  120  and  124  are integrally connected. It will also be appreciated that in other embodiments seal sub  100  may be constructed of several components that are coupled to one another. 
         [0072]    In a preferred embodiment, the JABS may be installed downhole as follows. Ball setting tool  500  is coupled to the end of a washpipe, and seal ball  204  is coupled to seal ball connection point  504  using shear pin  412 . Seal sub  100  is made up to within a gravel pack assembly. Said gravel pack assembly is made up using methods and other components well known in the art, such as packers, extensions, service tools, polished bore receptacles, port closure sleeves, screens, etc., with the outer pipe of a gravel pack service tool being made up to the outer housing of the gravel pack assembly and the inner pipe of the gravel pack service tool being made up to the washpipe to which ball setting tool  500  is coupled. The gravel pack assembly is then run downhole. Once the gravel pack assembly reaches the desired location, a packer in the gravel pack assembly is set by the gravel pack service tool, which disengages from the outer housing of the gravel pack assembly, which includes seal sub  100 , from the gravel pack service tool. 
         [0073]    When sealing seal sub  100  is desired, the gravel pack service tool is picked up, causing the washpipe, ball setting tool  500 , and seal ball  204  to move uphole. As the gravel pack service tool is pulled uphole, the washpipe is pulled through seal sub  100 , moving seal ball  204  closer to seal sub  100 . As the washpipe is pulled through seal sub  100 , ball setting tool  500  and seal ball  204  enter ball receiving channel  304 . Further pulling of the washpipe causes gripping feature  404  of seal ball  204  to engage with gripping feature  308  of seal sub  100  and bonded seal area  408  of seal ball  204  to seal against ball seat  312 . The larger diameter of seal ball  204  in comparison to the internal diameter of ball seat  312  prevents seal ball  204  from passing through sealable channel  316 . To complete the setting of seal ball  204 , the washpipe is pulled with sufficient force to cause shear pin  412  to shear, resulting in seal ball  204  breaking free from ball setting tool  500 . 
         [0074]    Once seal ball  204  is set, the service tool and washpipe can be returned to the surface. The well is isolated and sealed above and below seal sub  100 . Once sealed, seal sub  100  and seal ball  204  will withstand a predetermined amount of pressure X from above the seal, and a predetermined amount of pressure Y from below the seal. In a preferred embodiment, pressure Y is greater than pressure X, however it will be appreciated by one skilled in the art that in other preferred embodiments pressure X will be greater than or equal to pressure Y. 
         [0075]    When it is no longer desirable to maintain the seal of seal sub  100 , seal ball  204  may be jettisoned from seal sub  100  by applying downhole pressure in excess of pressure X. Upon application of such amount of pressure, gripping feature  404  of seal ball  204  will shear, thereby disengaging seal ball  204  from seal sub  100  and allowing fluid to freely pass through sealable channel  316 . In some embodiments of the present invention, seal ball  204  will fall down the well. In some embodiments of the present invention, seal sub  100  may further comprise a catch device to prevent seal ball  204  from reentering ball receiving channel  304  and/or seal sub  100 . 
         [0076]    Now referring to  FIGS. 6A-6C , several views of an alternative preferred embodiment of the present invention are provided. The seal sub body  602  of seal sub  600  is cylindrical, with the exterior surface of seal sub  600  being disposed about central axis  604  and having a uniform outer diameter. In a preferred embodiment of the present invention, disposed within seal sub  600  are seal retaining nut assembly  606 , seal assembly  608 , grapple assembly  612 , and grapple stop sleeve  616 . Further, as will be described below, grapple shear screw  620  couples grapple assembly  612  to the interior wall of seal sub body  602 . The interior wall of seal sub body  602  further comprises grapple shear ring receiver  624  and grapple stop wall  628 . Sealable channel  632  is disposed between seal assembly  608  and grapple assembly  612 . Although seal ball  636  is shown in  FIGS. 6A-6C , seal ball  636  is not present in this location until after seal ball  636  has been jettisoned as described below, and is present in these figures for purposes of illustrating the use of the springs of grapple assembly  612  which are also described below. 
         [0077]    Now referring to  FIGS. 7A-7C , several views of seal retaining nut assembly  606  of an alternative preferred embodiment of the present invention are provided. Seal retaining nut assembly  606  secures seal assembly  608  in the correct location inside of seal sub body  602 . Seal retaining nut assembly  606  is comprised of retaining nut  704 , thrust washer  708 , spacing bushing  712 . In some preferred embodiments of the present invention, seal retaining nut assembly  606  is further comprised of a seal spring that is disposed about central axis  604  between thrust washer  708  and seal assembly  608  for the purpose of maintaining the integrity of the seal between seal ball  636  and ball seal  908  during the jettisoning process set forth below. 
         [0078]    Now referring to  FIGS. 8A-8C , several views of seal ball  636  of an alternative preferred embodiment of the present invention are provided. In the preferred embodiment, seal ball  636  is spherical, however it will be appreciated by one skilled in the art that a seal ball  636  of other shapes may be used to practice the invention disclosed herein, such as ovoidal or conical on one end. Seal ball  636  is comprised of seal receiving groove  804 , grapple catch  808 , and shear pin cavity  812 . 
         [0079]    Now referring to  FIGS. 9A-9C , several views of seal assembly  608  of an alternative preferred embodiment of the present invention are provided. In the preferred embodiment, seal assembly  608  is comprised of seal seat  904  and ball seal  908 . In a preferred embodiment, ball seal  908  is comprised of an elastic material capable of deforming into seal receiving groove  804 . 
         [0080]    Now referring to  FIG. 10A-10C , several views of grapple assembly  612  of an alternative preferred embodiment of the present invention are provided. In the preferred embodiment, grapple assembly  612  is comprised of grapple body  1000 , ball catch lip  1004 , collet fingers  1008 , grapple stop  1012 , shear ring groove  1016 , shear pin groove  1020 , and grapple springs  1024 . Collet fingers  1008  are disposed on the upper end of grapple body  1000  and grapple springs  1024  are disposed on the lower end of grapple body  1000 . In a preferred embodiment of the present invention, grapple body  1000  has an inner diameter that is greater than seal ball  636  to allow seal ball  636  to pass though. However, collet fingers  1008  are disposed about central axis  604  with a circumference that is smaller than the circumference of seal  636 , thereby requiring seal ball  636  to be pulled or pushed into collet fingers  1008  using force. Ball catch lip  1004  is disposed about the interior circumference of the top of collet fingers  1008 . Grapple body  1000  is further comprised of grapple stop  1012 , which is disposed about the lower of end of grapple body  1000 . Shear ring groove  1016  is disposed about grapple body  1000  and accommodates placement of shear ring  640 . Shear ring  640  further comprises protruding tabs disposed about the shear ring that are rated to shear value in accordance with the application in which the JABS is being applied. In some preferred embodiments, four grapple springs  1024  are disposed about the lower end of grapple body  1000 . In other preferred embodiments, more or less than four grapple springs  1024  may be present. Grapple springs  1024  are sufficiently flexible to allow seal ball  636  to pass through with the force provided by the pulling of washpipe, but sufficiently rigid to prevent seal ball  636  from passing through with the force provided by production fluids being extracted from a well. For example, grapple springs  1024  allow seal ball  636  to be pulled through by a washpipe, but do not allow seal ball  636  to reenter grapple assembly  612  when oil or other fluids are being produced from the well. In some embodiments, grapple springs  1024  are designed to break off in the event an intervention operation is desired. 
         [0081]    Now referring to  FIGS. 11A-11C , several views of grapple stop sleeve  616  of an alternative preferred embodiment of the present invention are provided. In the preferred embodiment, grapple stop sleeve  616  coupled to the interior of seal sub body  602  using screws  1104 . 
         [0082]    Now referring to  FIGS. 12A-12C , several views of an alternative preferred embodiment of the present invention once seal ball  636  has engaged with ball seal  908  and ball catch lip  1004 , but before shear pin  1204  has sheared, are provided. 
         [0083]    In a preferred embodiment, the alternative embodiment of the JABS shown in  FIGS. 6A through 12C  may be installed downhole as follows. Ball setting tool  500  is coupled to the end of a washpipe, and seal ball  636  is coupled to ball setting tool  500  by threading shear pin  1204  to seal ball connection point  504  and shear pin cavity  812 . Seal sub  100  is made up to a gravel pack assembly. Said gravel pack assembly is made up using methods and other components well known in the art, such as packers, extensions, service tools, polished bore receptacles, port closure sleeves, screens, etc., with the outer pipe of a gravel pack service tool being made up to the outer housing of the gravel pack assembly and the inner pipe of the gravel pack service tool being made up to the washpipe to which ball setting tool  500  is coupled. The gravel pack assembly is then run downhole. Once the gravel pack assembly reaches the desired location, a packer in the gravel pack assembly is set by the gravel pack service tool, which disengages the outer housing of the gravel pack assembly, which includes seal sub  100 , from the gravel pack service tool. 
         [0084]    When sealing seal sub  600  is desired, the gravel pack service tool is picked up, causing the washpipe, ball setting tool  500 , and seal ball  636  to move uphole. As the gravel pack service tool is pulled uphole, the washpipe is pulled through seal sub  600 , moving seal ball  636  closer to seal sub  600 . Once seal ball  636  reaches seal sub  600 , and as the washpipe continues to be pulled through seal sub  600 , seal ball  636  is pulled through grapple springs  1024 , grapple stop sleeve  616 , and grapple body  1000 . Continuing to pull the washpipe brings grapple catch  808  of seal ball  636  in contact with ball catch lip  1004 . Once grapple catch  808  engages with ball catch lip  1004 , further pulling of the washpipe results in the shearing of grapple shear screw  620 , resulting in grapple assembly  612  becoming disengaged from the interior of seal sub body  602 . 
         [0085]    Further pulling of the washpipe pulls ball setting tool  500 , seal ball  636 , and grapple assembly  612  uphole until grapple stop wall  628  meets grapple stop  1012 . At this position, grapple shear ring receiver  624  aligns with shear ring groove  1016  and shear ring  640  expands, with the protruding tabs of shear ring  640  engaging with grapple shear ring receiver  624 . Further, seal ball  636  engages with ball seal  908  with sufficient pressure that the elastic material of ball seal  908  deforms into seal receiving groove  804 . The seal between seal ball  636  and ball seal  908  is now engaged as shown in  FIGS. 12A-12C  and the well is isolated and sealed above and below seal sub  600 . Further pulling the washpipe using a predetermined amount of pressure greater than that for which shear pin  1204  is rated results in shear pin  1204  shearing from seal ball  636 . The service tool and washpipe can now be returned to the surface. Once sealed, seal sub  600  and seal ball  636  will withstand a predetermined amount of pressure X from above the seal, and a predetermined amount of pressure Y from below the seal. In a preferred embodiment, pressure Y is greater than pressure X, however it will be appreciated by one skilled in the art that in other preferred embodiments pressure X will be greater than or equal to pressure Y. 
         [0086]    When it is no longer desirable to maintain the seal of seal sub  600 , seal ball  636  may be jettisoned from seal sub  600  by applying downhole pressure in excess of pressure X. Upon application of such amount of pressure, the protruding tabs of shear ring  640  will shear, thereby disengaging grapple assembly  612  the interior of seal sub body  602 . Continuing to apply downward pressure on seal ball  636  results in ball seal  908 , seal ball  636 , and grapple assembly  612  being forced downward until grapple assembly  612  reaches grapple stop sleeve  616 . In some embodiments of the present invention, a secondary shear ring or other catch device will be used to reengage grapple assembly  612  in its original position shown in  FIGS. 6A-6C . In some preferred embodiments, ball seal  908  maintains its engagement with seal ball  636  in part due to the spring of retaining nut assembly  606  applying downward force on ball seal  908  as seal ball  636  is forced downwards. Once grapple assembly  612  reaches grapple stop sleeve  616 , further pressure results in seal ball  636  being jettisoned out of collet fingers  1008  and through grapple springs  1024 , allowing fluid to freely pass through sealable channel  632 . In some embodiments of the present invention, seal ball  636  will fall down the well. In some embodiments of the present invention, grapple springs  1024  prevent seal ball  636  from reentering sealable channel  632 . 
         [0087]    Now referring to  FIG. 13 , a cross-sectional view of yet another alternative preferred embodiment of the present invention is provided. The preferred embodiment disclosed in  FIG. 13  helps to eliminate the risk of debris jeopardizing the integrity of the seal between the seal ball and the seal by assembling the seal ball, seal, and grapple before running the assembly downhole. In such an embodiment, the integrity of the seal between the seal ball and the seal can be verified at surface rather than setting the seal downhole by mechanical means. In a preferred embodiment, seal sub  1304  is comprised of a cylindrical body, with the exterior surface of seal sub  1304  being disposed about a central axis and having a uniform outer diameter. The interior surface of seal sub  1304  is further comprised of collet lip  1328 , grapple stop wall  1316 , and pressure port  1332 . 
         [0088]    In a preferred embodiment, grapple assembly  1300  is comprised of grapple  1308  and a ball and seal assembly. Grapple  1308  is further comprised of bonded seals  1312 , collet teeth  1324 , and grapple stop  1320 . Bonded seals  1312  may be bonded directly to the exterior wall of grapple  1308  in some embodiments of the present invention. In other embodiments, bonded seals  1312  may be coupled to grapple  1308  through other methods known in the art, such as bonding bonded seals  1312  to metal rings that may then be coupled to grapple  1308  with or without the use of an o-ring. The ball and seal assembly of grapple assembly  1300  is comprised of seal ball  1348 , shear pins  1352 , seal piston  1340 , spring  1336 , and ball seat  1344 . 
         [0089]    In a preferred embodiment, the alternative embodiment of the JABS shown in  FIG. 13 . may be installed downhole as follows. The components of the ball and seal assembly are pre-assembled before grapple assembly  1300  is placed downhole. Seal ball  1348  is secured to grapple  1308  using shear pins  1352 . In the preferred embodiment, seal ball  1348  is spherical, however it will be appreciated by one skilled in the art that a seal ball  1348  of other shapes may be used to practice the invention disclosed herein, such as ovoidal or conical on one end. Shear pins  1352  are rated for the specific application so that shearing can occur at the predetermined amount of pressure X from above. Seal ball  1348  is secured against ball seat  1344  to form a seal. In some embodiments, ball seat  1344  may be constructed in a similar manner and of similar material as ball seal  908 . Once assembled, grapple assembly  1300  is made up to the end of a washpipe. 
         [0090]    Seal sub  100  is made up to a gravel pack assembly. Said gravel pack assembly is made up using methods and other components well known in the art, such as packers, extensions, service tools, polished bore receptacles, port closure sleeves, screens, etc., with the outer pipe of a gravel pack service tool being made up to the outer housing of the gravel pack assembly and the inner pipe of the gravel pack service tool being made up to the washpipe to which grapple assembly  1300  is coupled. The gravel pack assembly is then run downhole. Once the gravel pack assembly reaches the desired location, a packer in the gravel pack assembly is set by the gravel pack service tool, which disengages the outer housing of the gravel pack assembly, which includes seal sub  1304 , from the gravel pack service tool. 
         [0091]    When sealing seal sub  1304  is desired, the gravel pack service tool is picked up, causing the washpipe and grapple assembly  1300  to move uphole. As the gravel pack service tool is pulled uphole, the washpipe is pulled through seal sub  1304 , moving grapple assembly  1300  closer to seal sub  1304 . Once grapple assembly  1300  reaches seal sub  1304 , and as the washpipe continues to be pulled through seal sub  1304 , grapple assembly  1300  enters seal sub  1304 . As grapple assembly  1300  moves through seal sub  1304 , bonded seals  1312  interface with the interior wall of seal sub  1304  at the point where seal sub  1304  is at its narrowest internal diameter. The first of several bonded seals  1312  wipes any debris from the interior wall of seal sub  1304  as grapple assembly  1300  is pulled uphole. Simultaneously, collet teeth  1324  are forced to flex inwards until grapple assembly  1300  moves far enough uphole that collet teeth  1324  lock into collet lip  1328 . Once grapple stop  1320  reaches grapple stop wall  1316 , further pulling of the washpipe will not be possible until the washpipe is disengaged from grapple assembly  1300 . The washpipe may be disengaged through various means known in the art such as shearing of shear pins or mechanical rotation. 
         [0092]    Once grapple assembly has been locked into place, the well is isolated and sealed above and below seal sub  1304 . The channel passing through the internal diameter of grapple  1308  is sealed by seal ball  1348  and ball seat  1344 . The channel running between the outer diameter of grapple  1308  and the inner diameter of seal sub  1304  is sealed by bonded seals  1312 . Pressure from below seal sub  1304  assists in maintaining the integrity of the seal between seal ball  1348  and ball seat  1344  by energizing ball seat  1344  through pressure port  1332 . Pressure from above seal sub  1304  assists in maintaining the integrity of the seal between seal ball  1348  and ball seat  1344  by energizing ball seat  1344  through applying downward pressure on spring  1336  and seal piston  1340 . 
         [0093]    Once sealed, seal sub  1304  and seal ball  1348  will withstand a predetermined amount of pressure X from above the seal, and a predetermined amount of pressure Y from below the seal. In a preferred embodiment, pressure Y is greater than pressure X, however it will be appreciated by one skilled in the art that in other preferred embodiments pressure X will be greater than or equal to pressure Y. 
         [0094]    When it is no longer desirable to maintain the seal of seal sub  1304 , seal ball  1348  may be jettisoned from seal sub  1304  by applying downhole pressure in excess of pressure X. Upon application of such amount of pressure, shear pins  1352  will shear, thereby disengaging seal ball  1348  from the interior of grapple  1308 . 
         [0095]    In some embodiments of the present invention, seal ball  1348  will fall down the well. In some other embodiments of the present invention, grapple springs, such as grapple springs  1024 , may be included to prevent seal ball  1348  from reentering the sealable channel. 
         [0096]    Now referring to  FIGS. 14A and 14B , cross-sectional views of a ball catch sub  1400  is provided. In a preferred embodiment, the ball catch sub  1400  is positioned downhole of a seal sub  1416  with a seal ball  1420 . However, it will be appreciated that the ball catch sub  1400  could be positioned uphole. In the preferred embodiment, seal ball  1420  is spherical, however it will be appreciated by one skilled in the art that a seal ball  1420  of other shapes may be used to practice the invention disclosed herein, such as ovoidal or conical on one end. As described above, in some embodiments, a fluid pressure from an upper end of the well can be applied to the seal sub  1416  to dislodge the seal ball  1420  and to reverse the isolation of the well provided by the seal sub  1416 . The seal ball  1420  can simply fall downhole, or be retained by a feature of the seal sub  1416  such as grapple arms. The ball catch sub  1400  provides a further ability to store the seal ball  1420  once the seal ball  1420  has been dislodged and provides the free flow of fluid through the seal sub  1416  and the ball catch sub  1400 . 
         [0097]    The ball catch sub  1400  generally comprises a primary channel  1404 , a receiving volume  1408 , and a ball catch lever  1412 . The primary channel  1404  extends along a longitudinal length of the ball catch sub  1400  from a first end to a second end of the ball catch sub  1400 . The receiving volume is positioned adjacent the primary channel  1404  or at least in fluid communication with the primary channel  1404 . Lastly, the ball catch lever  1412  is positionable between a first position and a second position. In the first position, the ball catch lever  1412  extends partially into the primary channel  1404 . The ball catch lever  1412  may have ports or a shape that allows fluid to pass through or around the ball catch lever  1412 . When a seal ball  1420  is dislodged and travels downhole, the ball catch lever  1412  in the first position directs the seal ball  1420  into the receiving volume  1408 . 
         [0098]    To facilitate the change between the first and second positions of the ball catch lever  1412 , the ball catch lever  1412  may be hingedly connected to the ball catch sub  1400  at a point between the ends of the ball catch lever  1412 . Therefore, as the seal ball  1420  is directed into the receiving volume  1408 , the seal ball  1420  contacts a proximal end of the ball catch lever  1412  to rotate the ball catch lever  1412  from the first position to the second position. In the second position, the ball catch lever  1412  is oriented substantially parallel to the longitudinal dimension or axis of the primary channel  1404  and the overall ball catch sub  1400 . The ball catch lever  1412  in the second position at least partially defines the receiving volume  1408  and retains the seal ball  1420  in the receiving volume  1408 . Additional non-return features can be included to hold the ball catch lever  1412  in the second position. Thus, fluid is allowed to freely flow through the subs and the seal ball  1420  is secured. 
         [0099]    Now referring to  FIG. 15 , a cross-sectional view of a bypass sub  1500  is provided. The bypass sub  1500  is positioned uphole of a seal sub  1516 , but it will be appreciated that the bypass sub  1500  could be positioned downhole. The fluid communication between the seal sub  1516  and a pressure source at a surface location or uphole location transfers pressure to the seal sub  1516  to effect functions such as dislodging a seal ball. However, debris can accumulate in the well to prevent fluid communication from the surface and the seal sub  1516 , and debris can even prevent mechanical means from descending downhole to, for instance, dislodge the seal ball. Therefore, the bypass sub  1500  provides an additional path to transfer fluid pressure. In the depicted embodiment, the bypass sub  1500  has a bypass line  1504  that is connected to the bypass sub  1500 , and a primary channel therein, at a first point  1508  and a second point  1512 . Therefore, a fluid pressure can extend through the debris-free bypass line  1504  to the seal sub  1516 . While the bypass line  1504  is depicted as extending out of the primary channel, it will be appreciated that the bypass line  1504  could be a control line, an inner pipe annulus, etc. 
         [0100]    The 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. 
         [0101]    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. 
         [0102]    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.” 
         [0103]    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. 
         [0104]    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. 
         [0105]    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. 
         [0106]    The foregoing description of the 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. 
         [0107]    Consequently, variations and modifications commensurate with the above teachings and skill and knowledge of the relevant art are within the scope of the 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 invention. Thus, it is intended that the claims be construed to include alternative embodiments to the extent permitted by the prior art.

Technology Category: 0