Abstract:
An inverted seal including a disintegrable body, one or more inside dimension seals disposed in the body. A method for removing an inverted seal from a downhole environment including exposing the body of the inverted seal to a condition to which it is responsive, disintegrating a portion of the body. A method for deploying a conventional seal after an inverted seal in a borehole including positioning an inverted seal in a downhole location, utilizing the inverted seal for its intended purpose, removing at least a portion of a body of the inverted seal, running a conventional seal further downhole of the location of the inverted seal.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a continuation application of U.S. Ser. No. 15/074,079, which was filed on Mar. 18, 2016, which is a divisional application of U.S. Ser. No. 13/308,760, which was filed on Dec. 1, 2011, and now U.S. Pat. No. 9,334,702, issued May 10, 2016, the disclosures of which are incorporated herein in their entireties. This application is also a continuation application of U.S. Ser. No. 14/485,020 filed on Sep. 12, 2014, which is incorporated herein by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    Seals are used ubiquitously in the downhole drilling and completions industry. Commonly seals are disposed on the outer surface of a radially inwardly disposed tubular. However, so-called inverted seals have gained favor for use in gravel pack operations as they enable the use of a slick outer diameter (OD) crossover tool. These slick OD crossover tools have several advantages over prior crossover tools, which include shoulders and seal elements bonded thereon that can become stuck on other components during run-in and pull out of the tool and adjacent tools. However, the inverted seals often become damaged during gravel pack operations and are unreliable during production after the crossover tool has been removed. Accordingly, the industry always well receives advances in seal technology in general and inverted seal technology specifically. 
       BRIEF DESCRIPTION 
       [0003]    A seal assembly includes a first tubular having a sealing surface, and a seal element run with the first tubular and displaced from the surface. The seal element initially having a radial dimension that forms a radially innermost or outermost sealing dimension of the first tubular for enabling the first tubular to be sealed with a second tubular radially disposed with the first tubular. A mechanism is triggerable by axial movement for reconfiguring the radial dimension of the seal element. The sealing surface of the first tubular operatively forming the radially innermost or outermost sealing dimension of the first tubular when the radial dimension of the seal element has been reconfigured for enabling the sealing surface of the first tubular to receive a second seal element. The seal element is axially compressed and released to change the radial dimension of the seal element. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0004]    The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike: 
           [0005]      FIG. 1  is a quarter-sectional view of an assembly having a seal element engaged between two tubulars; 
           [0006]      FIG. 2  is a quarter-sectional view of the assembly of  FIG. 1  where the seal element is disabled or deactivated from sealing the tubulars; 
           [0007]      FIG. 3  is a quarter-sectional view of an assembly including a seal element engaged between two tubulars; 
           [0008]      FIG. 4  is a quarter-sectional view of the assembly of  FIG. 1  where axial movement of a sleeve has disabled or deactivated the seal element from sealing the tubulars; 
           [0009]      FIG. 5  is a quarter-sectional view of an assembly including a seal element engagable between two tubulars; 
           [0010]      FIG. 6  is a quarter-sectional view of the assembly of  FIG. 5  where axial movement of the seal element has disabled or deactivated the seal element from sealing between tubulars; 
           [0011]      FIG. 7  is a quarter-sectional view of an assembly including a seal element engagable between two tubulars; 
           [0012]      FIG. 8  is a quarter-sectional view of the assembly of  FIG. 7  where axial movement of a piston has disabled or deactivated the seal element from sealing between tubulars; 
           [0013]      FIG. 9  is a quarter-sectional view of an assembly including a seal element engagable between two tubulars; and 
           [0014]      FIG. 10  is a quarter-sectional view of the assembly of  FIG. 9  where removal of a support has disabled or deactivated the seal element from sealing between tubulars. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures. 
         [0016]    Referring now to the embodiment of  FIGS. 1 and 2 , a selectively disengagable or deactivatable seal assembly  10  is shown having a seal element  12 . The seal element  12  is disposed with a first tubular  14  in order to form a sealed engagement with a second tubular  16 . The tubular  14  is positionable radially outwardly of the tubular  16  or vice-versa. In one embodiment the seal element  12  is an inverted seal, the first tubular  14  is part of an outer tubular string, and the second tubular  16  is a crossover tool housed within the tubular  14  for performing a fracturing and/or gravel pack operation. Of course, the tubulars  14  and  16  could be other tubulars arranged differently and used for other purposes. 
         [0017]    The assembly  10  is arranged with a mechanism for enabling the seal element  12  to selectively disengage from its sealed engagement with one or both of the tubulars  14  and  16 . Various embodiments of mechanisms will be described below with respect to  FIGS. 3-10 , but it is now noted that mechanism is generally defined to mean any property, device, assembly, system, parameter, tool, etc., or combinations of the foregoing, which enables the seal element  12  to selectively disengage, deactivate, or disable (these terms used interchangeably herein) the sealing ability of the seal element  12 . As the mechanism can take a variety of forms, it may generally be referred to herein that the mechanism is “triggered”, although other terms such as actuated, activated, launched, deployed, initiated, etc. may interchangeably be used to designate that some action is being performed related to the mechanism for disengaging the seal. 
         [0018]      FIGS. 1 and 2  schematically illustrate the seal element  12  being disengaged. Initially, the seal element  12  extends radially from the tubular  14  a distance xl such that a radial dimension of the seal element  12  effectively defines a radially innermost or outermost dimension for the tubular  14 , referred to collectively as the “radial sealing dimension” for ease in discussion. That is, in some embodiments, the radial sealing dimension is an inner diameter or an outer diameter. As the seal element  12  forms the radial sealing dimension, e.g., the seal element  12  radially protrudes from the tubular  14 , the seal element  12  is arranged to form a sealed engagement with the tubular  16 , as shown in  FIG. 1 . As a result of the mechanism being triggered (again, various embodiments described in more detail below with respect to  FIGS. 3-10 ) the seal element  12  is changed in radial dimension, namely, moved a distance x 2  from a surface  18  of the tubular  14 . Thus, after triggering the mechanism, the surface  18  (or some other surface of the tubular  14 ) then defines the radial sealing dimension for the tubular  14 , i.e., the radially innermost (or outermost) dimension. For example, the surface  18  could be formed as a seal bore for receiving a conventional style seal element run-in on an isolation string after the tubular  16 , e.g., a crossover tool, is pulled out. For example, the distance x 2  could be greater than or equal to zero. In some embodiments, the seal element  12  or portions thereof may extend radially beyond the tubular  14  to some relatively small or insignificant degree, but nevertheless the engagement with the tubular  16  is disabled and the surface  18  is used for resealing the tubular  14 . 
         [0019]    As noted above, one potential embodiment for use of the assembly  10  and others described herein is for sealing against a crossover tool with inverted seals during a gravel pack operation. After the operations are completed at each desired zone and the crossover tool is no longer needed, the crossover tool can be pulled out of the hole and the inverted seals disengaged or deactivated as schematically described above. After deactivation or disengagement, the inverted seals no longer form the radial sealing dimension, i.e., the innermost diameter, of the outer tubular string. Thus, the inverted seals are changed in radial dimension, e.g., moved radially, so that a typical isolation assembly can be run-in with production tubing and sealed into seal bores or the like in the outer tubular string. This avoids the disadvantages of inverted seals, which are often damaged during gravel pack operations and inherently unreliable thereafter. Of course, other seal elements, including non-inverted seals could be similarly deactivated in any desired system, although multi and single zone completions are prime candidates for the currently described assemblies. 
         [0020]    One embodiment is shown in  FIGS. 3 and 4 , in which an assembly  20  is shown between an engaged and a disengaged state, respectively. The assembly  20  resembles the assembly  10  in basic concept, i.e., having a seal element  22  that is arranged for selectively disengaging from sealed engagement between a first tubular  24  and a second tubular  26 . Similar to the assembly  10 , the tubulars  24  could be positioned radially outwardly of the tubular  26  or vice-versa. The tubulars  24  and  26  could respectively be an outer tubular string and a crossover tool, etc. Multiple ones of the assembly  20  could be included along the length of the tubular string  24  in order to, for example, perform a multi-zone fracturing operation. 
         [0021]    In the assembly  20 , for example, the seal element  22  is held by a housing that comprises a set of rings  28   a  and  28   b.  Both of the rings  28   a  and  28   b  are secured or locked to the tubular  24 . For example, in the embodiment of  FIGS. 3 and 4 , a threaded connection  30  and a connector  32  are utilized for respectively securing the rings  28   a  and  28   b  to the tubular  24 , although other means of connection are appreciable by one of ordinary skill in the art. 
         [0022]    The connector  32  is located in a slot  34  of a sleeve  36  for enabling the sleeve  36  to move axially with respect to the tubular  24 . The seal element  22  is radially deformed (either compressed or swaged outward, depending on the relative radial orientation of the tubulars  24  and  26 ) into place by the sleeve  36 . When radially deformed, the seal element  22  forms a sealed engagement between the tubulars  24  and  26 . Upon axial movement of the sleeve  36 , a narrowed portion  38  of the sleeve  36  is aligned with the seal element  22 , enabling the seal element  22  to at least partially return to an orientation in which it is not deformed. That is, the seal element  22  could spring radially outward or inward toward its rest or neutral configuration. As shown in  FIG. 4 , when aligned with the narrowed end  38  the seal element  22  changes in radial dimension so that it no longer forms the radial sealing dimension for the tubular  24 . Instead, the radial sealing dimension is formed by a surface of the rings  28   a  and  28   b  (or some other surface connected to the tubular  24 ). In this way, the sleeve  36  with the narrowed end  38  acts as a mechanism that can be triggered for disengagement of the seal element  22 . 
         [0023]    The sleeve  36  has, for example, a profile  40  for engaging with a complementarily profiled shifting tool in order to move the sleeve  36 , although it is to be recognized that any other method of shifting the sleeve  36  could be utilized. In embodiments in which an isolation string is run-in after deactivation of the seals, such a shifting tool could be included at the leading end of the isolation string, and one or more of the assemblies  20  deactivated by, for example, setting weight down on the sleeve  36  to engage the shifting tool with the profile  40 , pulling up on the isolation string to shift the sleeve  36 , running the isolation string to another sleeve, etc. 
         [0024]    It is to be appreciated that modifications to any of the assemblies described herein are possible. For example, in an embodiment similar to that of the assembly  20  the seal element is movable and the sleeve is stationary. That is, for example, with reference to the numbered components of the assembly  20 , the sleeve  36  could be secured, locked to, or formed with the tubular  24  and the seal element  22  slideable therein in order to align the seal element  22  with the narrowed portion  38  of the sleeve  36 . 
         [0025]    In some embodiments, such as shown in  FIGS. 3-4 , axial actuation of a component, e.g. a sleeve or the seal element itself, disables the seal element. In other embodiments, rotational movement could result in a radial change, e.g., the mechanism including or resembling a cam, four-bar linkage, camera aperture, etc. The seal element is disabled in other embodiments by removing the seal element. In some of these embodiments, the seal element is removable via physical means, such as a cutter, blade, mill, drill, etc. that is hydraulically, mechanically, gravitationally, electrically, etc. actuated for removing a portion of the seal element by cutting, shearing, etc. In some embodiments, the seal element (or a ring, c-ring, or other member or members disposed therein or secured thereto) is at least partially plastically deformable and a wedge or other component axially runnable for radially deforming or swaging the seal element. In other embodiments, the seal element is removed by spotting or delivering a fluid, such as an acid, a solvent, etc. to the seal element in order to degrade, disintegrate, dissolve, corrode, weaken, destroy, or otherwise remove the seal element or a portion thereof (collectively, “degrade”). Similarly, a change in temperature, pressure, or some other downhole condition or parameter could degrade, change the dimensions of, or otherwise trigger the mechanism for disabling the seal element. In view of these embodiments, it is clear that the term “mechanism” is used in its broadest sense, as the mechanism or components thereof may range from physical tools, e.g., a mill or blade, to the seal element itself, to a property of the seal element, e.g., dissolvability in the presence of the proper fluid. 
         [0026]    Axial movement, e.g., of a tool, device, the seal element, etc. could be used for triggering mechanisms in various other embodiments. For example, seal elements could be included on or bonded to a barrel slip assembly, with axial movement between the interlocking jaws of the barrel slips resulting in a change in the radial positioning of the seal elements. For example, a barrel slip assembly is disclosed in U.S. Pat. No. 7,367,397 (Clemens et al.), which patent is hereby incorporated in its entirety. By placing, for example, seal elements at the inner surface of the “slip body 188” of Clemens et al., the seal elements could be selectively disengaged or disabled by moving the “annular wedge assemblies 196, 198” together and apart. 
         [0027]    In other embodiments, axial movement enables an axially pre-compressed or axially pre-stretched or tensioned seal element to return to its rest position. For example, similar to a compression-set packer, the seal element could be compressed between two components, e.g., by a hydraulic pressure, set down weight, etc. In another such embodiment, shown in  FIGS. 5 and 6 , an assembly  42  includes a deformable body  44  having seal elements  46  thereon. By axially compressing and/or tensioning the body  44  between two components and/or enabling the ring  44  to return to its rest or neutral position after ceasing the compression/tension, the radial dimension of the seal elements  46  can be set. 
         [0028]    Another such embodiment utilizing compression/tension of the seal element is shown in  FIGS. 7 and 8 , namely, an assembly  48 . The assembly  48  includes a seal element  50 . According to the embodiment of  FIG. 7 , the seal element  50  is initially axially compressed between a portion or component of a tubular  52  and a piston  54  for forcing the seal element  50  to compress axially and bulge radially. The piston  54  could take the form, e.g., of a ring. The piston  54  is initially held in place by a release member, shown in the form of a shear screw or pin  56 , but which could take other forms, such as collet fingers, a shear ring, etc. The piston  54  is disposed between a pair of chambers  58  and  60 . In one embodiment, the chamber  60  is at atmospheric or some relatively low pressure. Thus, upon pressurizing the chamber  58  to a predetermined amount, the release member will release the piston  54 , e.g., the screws  56  will shear, moving the piston  54  axially and enabling the previous compressed seal element  50  to return to its rest position. In a related embodiment, the shear screws could be removed and the seal element  50  compressed by maintaining a high pressure in the chamber  60  and the seal element released by bleeding off the pressure in the chamber  60 . Of course, other mechanisms could be employed that compress or tension seal elements in other ways. 
         [0029]    An assembly  62  is another embodiment shown in  FIGS. 9 and 10 . In the embodiment of the assembly  62 , a seal element  64  is included with a tubular  66  as being radially compressible or expandable and/or having a resilient member  68 . For example, the member  68  could be a c-ring or other resilient or spring-like member that naturally springs, snaps, or otherwise returns back to its neutral position after being radially deformed. The seal element  64  in this embodiment is initially supported by a support member  70 . In some embodiments, a secondary seal element  72  is included to seal the support member  70  to the tubular  66 . The support member  70  could be removed in any desired manner in order to enable the seal element  64  and/or the member  68  to radially reposition the seal element  64  for disabling or disengaging the seal member  64 . 
         [0030]    In one embodiment the support member  70  is a frangible or breakable material, e.g., tempered glass, that is hit, punched, rammed, or otherwise struck or met by a force in order to shatter or break the support member. For example, a piston, pin, rod, finger, spike, etc. could be driven into the support member  68  using means such as hydraulics, pneumatics, string weight, etc. Similarly, a large compressive force could be increasingly applied over a relatively large surface area to crack or shatter the member  68 . 
         [0031]    In another embodiment, the support member  70  is made from controlled electrolytic metallic materials or some other material that can be degraded, dissolved, disintegrated, corroded, weakened, etc. (collectively, “degraded”) by exposure to a predetermined fluid. Examples of suitable materials and their methods of manufacture are given in United States Patent Publication No. 2011/0135953 (Xu, et al.), which Patent Publication is hereby incorporated by reference in its entirety. Suitable materials are also available from Baker Hughes Incorporated under the name IN-TALLIC®. Other materials include magnesium, aluminum, etc. that are removable by exposure to acid, etc. The support member  70  could be at least partially hollow, perforated, weakened, etc. to aid in its removal. 
         [0032]    Of course, any combination of elements from the above described embodiments, or substitutes, equivalents, analogs, etc. thereof or therefore are also within the scope of the current invention. In this way, triggering of some mechanism can be used to reconfigure the radial dimension of the seal element for selectively disabling or deactivating its seal sealing capability. Further, the tubular including the seal element can include a seal bore or other surface, e.g., the surface  18  in  FIG. 1 , for receiving a new seal element from another tubular such that additional operations requiring isolation, e.g., production, can be performed. 
         [0033]    While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.