Patent Publication Number: US-2022228453-A1

Title: Modular downhole packer

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a non-provisional application which claims priority from U.S. provisional application No. 63/138,476, filed Jan. 17, 2021, which is hereby incorporated by reference in its entirety. 
    
    
     TECHNICAL FIELD/FIELD OF THE DISCLOSURE 
     The present disclosure relates generally to wellbore isolation devices, and specifically to elements for inflatable packers. 
     BACKGROUND OF THE DISCLOSURE 
     Fluid-energized, or inflatable, packers are isolation devices used in a downhole wellbore to seal against the inside of the wellbore or a downhole tubular to separate the section of wellbore or tubular on one side of the inflatable packer from that on the other side of the inflatable packer. Typical inflatable packers use elastic bladders positioned on the outside of a precision mandrel which, in response to an increased pressure within the bladder, expand until they contact the surrounding wellbore or tubular. Continued expansion causes an increase in contact area and force between the bladder and the wellbore or tubular, thereby sealing the annular space around the packer. 
     SUMMARY 
     The present disclosure provides for a modular downhole packer. The modular downhole packer may include a valve body, the valve body including a threaded coupler adapted to couple to a tubular and a valve assembly. The modular downhole packer may include a packer element assembly. The packer element assembly may include a first end coupler, the first end coupler mechanically coupled to the valve body; a packer element; and a second end coupler. The modular downhole packer may include a floating seal element, the floating seal element mechanically coupled to the second end coupler, the floating seal element including a seal extension. The modular downhole packer may include a floating end anchor. The floating end anchor may include a compression seal housing, the compression seal housing including an outer sealing surface positioned within the seal extension of the second end coupler; a compression seal positioned within a seal pocket formed in the compression seal housing; and an anchor body, the anchor body threadedly coupled to the seal pocket of the compression seal housing, the anchor body abutting the compression seal. 
     The present disclosure also provides for a method. The method may include providing a tubular, the tubular having a threaded end. The method may include mechanically coupling a valve housing to the threaded end of the tubular. The method may include mechanically coupling a packer element assembly to the valve housing. The packer element assembly may be positioned about the tubular. The method may include mechanically coupling a floating seal element to the packer element assembly; mechanically coupling a floating end anchor to the floating seal element, the floating end anchor including a compression seal; compressing the compression seal to the tubular; and anchoring the floating end anchor to the tubular. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present disclosure is best understood from the following detailed description when read with the accompanying figures. It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion. 
         FIG. 1  depicts a side elevation view of a modular downhole packer positioned on a tubular member consistent with at least one embodiment of the present disclosure. 
         FIG. 2  depicts a cross section view of the modular downhole packer of  FIG. 1 . 
         FIG. 3  depicts a partial cross section view of modular downhole packer consistent with at least one embodiment of the present disclosure. 
         FIG. 4  depicts a partial cross section view of a modular downhole packer consistent with at least one embodiment of the present disclosure. 
         FIG. 5  depicts a partial cross section view of the modular downhole packer of  FIG. 4  in an anchored position. 
         FIG. 6  depicts a partial cross section view of the modular downhole packer of  FIG. 4  in a set position. 
     
    
    
     DETAILED DESCRIPTION 
     It is to be understood that the following disclosure provides many different embodiments, or examples, for implementing different features of various embodiments. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed. 
       FIGS. 1, 2  depict modular downhole packer system  100 . Modular downhole packer system  100  may include valve body  101 . Valve body  101  may, in some embodiments, be generally tubular and may include first threaded coupler  103  and second threaded coupler  105 . First and second threaded couplers  103 ,  105  may be positioned to allow valve body  101  to be threadedly coupled to a tubular string such as a casing string for use in a wellbore. In some embodiments, first threaded coupler  103  may be used to couple to tubular members of the casing string above or below modular downhole packer system  100  and second threaded coupler  105  may couple to tubular  107 , which may be used as a mandrel of modular downhole packer system  100  as further described below. Tubular  107  may be a piece of casing or other tubular used within a wellbore. Unlike a traditional mandrel for an inflatable packer, tubular  107  does not need a precision-finished outer surface and may be provided from, for example and without limitation, normal, unmodified casing or drill pipe used during a casing operation of a wellbore as found on a wellsite. Thus, specialized mandrels are not required to use modular downhole packer system  100  and thus do not need to be manufactured, stocked, or shipped to the wellsite. Additionally, tubular  107  may be mechanically coupled to valve body  101  by threading tubular  107  to second threaded coupler  105  of valve body  101  using an existing threaded end of tubular  107 , rather than relying on a welded connection between mandrel and valve body as would be required in a traditional inflatable packer. 
     In some embodiments, valve body  101  may include valve assembly  109  positioned to allow for the actuation of modular downhole packer system  100  using fluid pressure from within valve body  101  as provided through the tubular string within which modular downhole packer system  100  is included as further described below. 
     In some embodiments, modular downhole packer system  100  may include packer element assembly  121 . Packer element assembly  121  may be tubular in shape and may be positioned about and extend along tubular  107 . In some embodiments, packer element assembly  121  may include first end coupler  123 , packer element  125 , and second end coupler  127 . First end coupler  123  and second end coupler  127  may be mechanically coupled to packer element  125  such that packer element  125  is positioned about tubular  107 . The annular space between packer element  125  and tubular  107  may be defined as interior cavity  129  of modular downhole packer system  100  and may be sealed to tubular  107  as further described below such that when fluid pressure within interior cavity  129  increases, packer element  125  inflates and moves radially outward from tubular  107 . 
     In some embodiments, first end coupler  123  may, as shown in  FIG. 3 , threadedly couple to valve body  101  at element coupler  111  of valve body  101 . In other embodiments, first end coupler  123  may be mechanically coupled to valve body  101  using one or more of set screws, snap rings, or a press fit. In some embodiments, element coupler  111  may be formed on the outer diameter of valve body  101  while second threaded coupler  105  is formed on the inner diameter of valve body  101  within element coupler  111 . In some embodiments, valve body  101  may fluidly seal against both tubular  107  and first end coupler  123 , thereby defining one end of interior cavity  129 . In some embodiments, valve assembly  109  may be fluidly coupled to interior cavity  129  to allow for inflation of packer element  125 . 
     In some embodiments, second end coupler  127  may be threadedly coupled to floating seal element  131  at element coupler  133 . In other embodiments, second end coupler  127  may be mechanically coupled to floating seal element  131  by, for example and without limitation, one or more of set screws, snap rings, or a press fit. As shown in  FIG. 2 , floating seal element  131  may be generally tubular and may be positioned about tubular  107 . In some embodiments, floating seal element  131  may include seal extension  135 . Seal extension  135  may be formed at the end of floating seal element  131  opposite element coupler  133 . Seal extension  135  may include inner sealing surface  137 . 
     In some embodiments, modular downhole packer system  100  may include floating end anchor  151 . Floating end anchor  151  may mechanically couple to tubular  107  and may, as discussed below, provide for a surface against which seal extension  135  of second end coupler  127  may fluidly seal, thus defining the other end of interior cavity  129  of packer element assembly  121 . 
     In some embodiments, as shown in  FIG. 4 , floating end anchor  151  may include compression seal housing  153 . Compression seal housing  153  may be positioned about tubular  107 . Compression seal housing  153  may include outer sealing surface  155 . Outer sealing surface  155  may be generally cylindrical and may extend along tubular  107  in the direction of valve body  101 . In some embodiments, outer sealing surface  155  may receive seal extension  135  of floating seal element  131 . Compression seal housing  153  may be mechanically fixed to tubular  107  while floating seal element  131  is able to move relative to tubular  107  and compression seal housing  153  during actuation of modular downhole packer system  100  as further described below. 
     In some embodiments, one or more seals  141  may be positioned between inner sealing surface  137  and outer sealing surface  155 . For example and without limitation, as shown in  FIG. 4 , seals  141  may be positioned in seal grooves  143  formed in inner sealing surface  137 . In other embodiments, seals  141  may be positioned in seal grooves formed in outer sealing surface  155  or may be positioned in both inner sealing surface  137  and outer sealing surface  155 . In some embodiments, one or both of inner sealing surface  137  and outer sealing surface  155  may be formed at a sufficient tolerance such that seals  141  maintain a fluid seal against the respective surface throughout the full range of motion of floating seal element  131  during actuation of modular downhole packer system  100 . Unlike a typical inflatable packer, for example and without being bound to theory, the surface quality and dimensional accuracy of tubular  107  does not affect the ability of modular downhole packer system  100  to maintain a fluid seal during actuation thereof. Tubular  107  may therefore be formed from an ordinary tubular element rather than a precision-formed mandrel as in a typical inflatable packer. 
     In some embodiments, floating end anchor  151  may include compression seal  157 . Compression seal  157  may be positioned about tubular  107  within seal pocket  159  formed in compression seal housing  153 . In some embodiments, floating end anchor  151  may further include compression seal backup rings  161  positioned about tubular  107  abutting each end of compression seal  157 . Seal backup rings  161  may, in some embodiments, engage compression seal  157  and may, without being bound to theory, reduce extrusion of compression seal  157  during actuation of compression seal  157  as further described below. 
     In some embodiments, floating end anchor  151  may include anchor body  163 . Anchor body  163  may be tubular or annular and may be positioned about tubular  107 . In some embodiments, anchor body  163  may include external compression threads  165  positioned to engage with inner compression threads  167  formed in seal pocket of compression seal housing  153 . Anchor body  163  may thereby be threadedly coupled to compression seal housing  153 . 
     In some embodiments, as anchor body  163  is threadedly tightened to compression seal housing  153 , anchor body  163  may engage compression seal  157  (via, in some embodiments, seal backup rings  161 ) and may longitudinally compress compression seal  157  as shown in  FIG. 5 . Such compression may, in some embodiments, cause compression seal  157  to deform into contact with tubular  107  and compression seal housing  153  such that compression seal  157  creates a fluid seal therebetween. In some embodiments, as compression seal  157  is deformed against the outer surface of tubular  107 , compression seal  157  may conform to the outer profile of tubular  107 , thereby compensating for any surface defects or tolerance offsets in the outer surface of tubular  107  caused by the use of ordinary, non-precision tubular members. Compression seal  157  may therefore provide a seal against tubular  107  for the other sealed end of interior cavity  129 . 
     In some embodiments, anchor body  163  may include one or more threaded holes  169  formed radially through anchor body  163  adapted to receive set screws  171 . Once compression seal  157  is sufficiently compressed due to threaded engagement between anchor body  163  and compression seal housing  153 , set screws  171  may be further threadedly engaged to anchor body  163  until set screws  171  engage against tubular  107 , Such engagement may, for example and without limitation, retain anchor body  163  and compression seal housing  153  in position relative to tubular  107  and may reduce or prevent relative rotation between anchor body  163  and compression seal housing  153 , thereby maintaining the engagement of compression seal  157  and tubular  107 . 
     In some embodiments, components of modular downhole packer system  100  may be supplied to a wellsite in a disassembled condition excluding tubular  107 , which may be sourced from casing already found at the wellsite. In order to assemble modular downhole packer system  100 , valve body  101  may be threadedly coupled to tubular  107  at second threaded coupler  105  of valve body  101  using an existing threaded end of tubular  107 . 
     Packer element assembly  121 , second end coupler  127 , and floating end anchor  151  may also be positioned about tubular  107 . Packer element assembly  121  may be threadedly coupled to valve body  101 , and floating seal element  131  may be threadedly coupled to packer element assembly  121 . Floating end anchor  151  may be positioned such that compression seal housing  153  is positioned within seal extension  135  of floating seal element  131 , defined as an unset position as shown in  FIG. 4 . 
     Anchor body  163  may then be rotated relative to compression seal housing  153  until compression seal  157  is compressed into engagement with tubular  107  and compression seal housing  153 . Set screws  171  may then be rotated into engagement with tubular  107 , defining an anchored position as shown in  FIG. 5  such that floating end anchor  151  is fixedly coupled to tubular  107 . Such a configuration may also be referred to as an assembled or run-in configuration of modular downhole packer system  100 . 
     Modular downhole packer system  100  may then be made up into a tubular string such as a casing string using first threaded coupler  103  of valve body  101  and, in some embodiments, the other existing threaded end of tubular  107 . Modular downhole packer system  100  may be positioned at a desired position within a wellbore at which time modular downhole packer system  100  may be actuated. In such an actuation operation, fluid pressure from within valve body  101  may be selectively transferred to interior cavity  129  via valve assembly  109  of valve body  101 , thereby causing packer element  125  to inflate radially into engagement with a wellbore or surrounding tubular. In some embodiments, as packer element  125  extends radially, second end coupler  127  may move longitudinally along tubular  107 . In other embodiments, second end coupler  127  may remain fixed in position along tubular  107 . 
     In some embodiments, as shown in  FIG. 6 , because second end coupler  127  is mechanically coupled to floating seal element  131 , floating seal element  131  also moves longitudinally along tubular  107  such that seal extension  135  moves relative to compression seal housing  153 , which is anchored in place along tubular  107  by set screws  171  as discussed above. During such movement, seals  141  maintain the fluid seal between floating seal element  131  and compression seal housing  153 , thereby containing fluid pressure within interior cavity  129 . Such movement continues until packer element  125  is fully engaged to the surrounding wellbore or tubular, defining a set position of modular downhole packer system  100 . Valve assembly  109  may, in some embodiments, retain modular downhole packer system  100  in the set position. In other embodiments, floating seal element  131  may remain in position along tubular  107 . 
     The foregoing outlines features of several embodiments so that a person of ordinary skill in the art may better understand the aspects of the present disclosure. Such features may be replaced by any one of numerous equivalent alternatives, only some of which are disclosed herein. One of ordinary skill in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. One of ordinary skill in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure and that they may make various changes, substitutions, and alterations herein without departing from the spirit and scope of the present disclosure.