Patent Publication Number: US-9422789-B2

Title: Fluid stabbing dog

Description:
BACKGROUND 
     This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the presently described embodiments. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present embodiments. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art. 
     In order to meet consumer and industrial demand for natural resources, companies often invest significant amounts of time and money in finding and extracting oil, natural gas, and other subterranean resources from the earth. Particularly, once a desired subterranean resource such as oil or natural gas is discovered, drilling and production systems are often employed to access and extract the resource. These systems may be located onshore or offshore depending on the location of a desired resource. 
     By way of example, an offshore drilling system typically includes a marine riser that connects a drilling rig to subsea wellhead equipment, such as a blowout preventer stack connected to a wellhead. A drill string can be run from the drilling rig through the marine riser into the well. Drilling mud can be routed into the well through the drill string and back up to the surface in the annulus between the drill string and the marine riser. Unexpected pressure spikes can sometimes occur in the annulus, such as from pressurized formation fluid entering the well (also referred to as a “kick”). For this reason, the marine riser can include a diverter for sealing the return path through the riser and redirecting flow away from the drill floor of the drilling rig. 
     SUMMARY 
     Certain aspects of some embodiments disclosed herein are set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of certain forms the invention might take and that these aspects are not intended to limit the scope of the invention. Indeed, the invention may encompass a variety of aspects that may not be set forth below. 
     Some embodiments of the present disclosure generally relate to locking dogs having extendable locking elements and stabs with passages for conveying fluid through the locking dogs to another device (e.g., a diverter). Such locking dogs are also referred to herein as stabbing dogs. In one embodiment, stabbing dogs are mounted on a housing for receiving a diverter. The stabbing dogs of this embodiment include locking elements with integral stabs disposed therein. The locking elements can be extended to engage a diverter and secure it within the housing. Extension of the locking elements also causes the stabs to engage the diverter and complete one or more fluid connections between the stabs and the diverter. Control fluid can then be routed into the diverter through the stabs of the stabbing dogs to control operation of the diverter. For instance, in one embodiment, control fluid may be provided through the stabbing dogs to control opening of an annular preventer in the diverter, closing of the annular preventer, and energizing of seals between the diverter and the housing. 
     Various refinements of the features noted above may exist in relation to various aspects of the present embodiments. Further features may also be incorporated in these various aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to one or more of the illustrated embodiments may be incorporated into any of the above-described aspects of the present disclosure alone or in any combination. Again, the brief summary presented above is intended only to familiarize the reader with certain aspects and contexts of some embodiments without limitation to the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and other features, aspects, and advantages of certain embodiments will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein: 
         FIG. 1  generally depicts a subsea system for accessing or extracting a resource, such as oil or natural gas, via a well in accordance with an embodiment of the present disclosure; 
         FIG. 2  is a block diagram of a diverter and other various components of riser equipment of  FIG. 1  in accordance with one embodiment; 
         FIG. 3  is an exploded view generally depicting a diverter, its housing, and locking dogs for holding the diverter within the housing in accordance with one embodiment; 
         FIG. 4  is a perspective view showing the diverter of  FIG. 3  received within its housing; 
         FIG. 5  is a block diagram generally representing fluid connections between a diverter, locking dogs, and a diverter control unit in accordance with one embodiment; 
         FIGS. 6 and 7  are perspective views of a locking dog having an extendable locking element and an integrated male fluid stab in accordance with one embodiment; 
         FIG. 8  is generally depicts alignment of the locking dog of  FIGS. 6 and 7  with a receptacle of a diverter for conveying fluid from the stab of the locking dog into the diverter in accordance with one embodiment; 
         FIGS. 9 and 10  are cross-sections of the locking dog and the receptacle of  FIG. 8  installed in the diverter and its housing, with the locking element and stab of the locking dog retracted in  FIG. 9  and extended into engagement with the receptacle in  FIG. 10 , in accordance with one embodiment; 
         FIG. 11  is a top plan view of the diverter and housing of  FIGS. 3 and 4 , and shows fluid connections from a connection plate to the locking dogs in accordance with one embodiment; 
         FIGS. 12 and 13  are section views generally depicting operation of an annular preventer of the diverter by way of control fluid routed into the diverter from locking dogs in accordance with one embodiment; and 
         FIG. 14  is a section view of a locking dog in fluid communication with a conduit of the diverter to enable control fluid pumped through the locking dog to energize flowline seals of the diverter in accordance with one embodiment. 
     
    
    
     DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
     One or more specific embodiments of the present disclosure will be described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
     When introducing elements of various embodiments, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Moreover, any use of “top,” “bottom,” “above,” “below,” other directional terms, and variations of these terms is made for convenience, but does not require any particular orientation of the components. 
     Turning now to the present figures, a system  10  is illustrated in  FIG. 1  in accordance with one embodiment. Notably, the system  10  (e.g., a drilling system or a production system) facilitates accessing or extraction of a resource, such as oil or natural gas, from a well  12 . Although the system  10  may take the form of an onshore system in other embodiments, the system  10  is depicted in  FIG. 1  as an offshore system that includes surface equipment  14 , riser equipment  16 , and stack equipment  18 , for accessing or extracting the resource from the well  12  via a wellhead  20 . In one subsea drilling application, the surface equipment  14  includes a drilling rig above the surface of the water, the stack equipment  18  (i.e., a wellhead assembly) is coupled to the wellhead  20  near the sea floor, and the riser equipment  16  connects the stack equipment  18  to the drilling rig and other surface equipment  14 . 
     As will be appreciated, the surface equipment  14  can include a variety of devices and systems, such as pumps, power supplies, cable and hose reels, a rotary table, a top drive, control units, a gimbal, a spider, and the like, in addition to the drilling rig. The stack equipment  18 , in turn, can include a number of components, such as blowout preventers, that enable control of fluid from the well  12 . Similarly, the riser equipment  16  can also include a variety of components, such as riser joints, flex joints, a telescoping joint, fill valves, a diverter, and control units, some of which are depicted in  FIG. 2  in accordance with one embodiment. 
     Particularly, in the embodiment of  FIG. 2 , the riser equipment  16  is provided in the form of a marine riser that includes a diverter  24 , an upper flex joint  26 , a telescoping joint  28 , riser joints  30 , and a lower flex joint  32 . A marine riser is generally a tube (typically including a series of riser joints  30 ) that connects an offshore drilling rig to wellhead equipment installed on the seabed. In some instances, a floating drilling rig (e.g., a semisubmersible or drilling ship) is used to drill the well  12 . Waves or other forces on the floating rig can cause the rig and other surface equipment  14  to move with respect to the stack equipment  18  at the well  12 . To accommodate such motion, the upper flex joint  26  can be connected to or near the surface equipment  14  and the lower flex joint  32  can be coupled to or near the stack equipment  18 . These flex joints  26  and  32  allow angular displacement of the riser string between these flex joints (including the telescoping joint  28  and the riser joints  30 ) and accommodate lateral motion of the floating rig on the water&#39;s surface above the stack equipment  18 . Complementing the flex joints  26  and  32 , the telescoping joint  28  compensates for heave (i.e. up-down motion) of the drilling rig generally caused by waves at the surface. 
     At various operational stages of the system  10 , fluid can be transmitted between the well  12  and the surface equipment  14  through the riser equipment  16 . For example, during drilling, a drill string is run from the surface, through a riser string of the riser equipment  16  (e.g., through the diverter  24 , the flex joints  26  and  32 , the telescoping joint  28 , and a series of connected riser joints  30 ), and into the well  12  to bore a hole in the seabed. Drilling fluid (also known as drilling mud) is circulated down into the well  12  through the drill string to remove well cuttings, and this fluid returns to the surface through the annulus between the drill string and the riser string. 
     The diverter  24  operates to protect the drilling rig and other surface equipment  14  from pressure kicks traveling up from the well  12  through the marine riser. Such pressure kicks can be caused by pressurized formation fluids entering the well  12 . As discussed in greater detail below, the diverter  24  includes an annular preventer for sealing the fluid path from the well  12  when a pressure kick is detected. The pressurized fluid during a kick can be routed away from the drilling rig through one or more ports in the diverter. In some embodiments, the diverter  24  is installed on the underside of a drill floor of a drilling rig and is connected to the upper flex joint  26  as part of a marine riser. 
     One example of a diverter  24  is illustrated in  FIGS. 3 and 4 . In this embodiment, the diverter  24  includes a body  40  sized to fit within a bore  42  of a diverter housing  38 . The diverter housing  38  can be mounted to the underside of a drilling rig floor. The diverter  24  includes multiple fluid ports  44  that allow fluid to pass out of the diverter  24 , through fluid ports  46  of the housing  38 , and into pipes (e.g., flowlines and diverter lines) connected to the housing. These pipes can include valves to control flow from the diverter  24 . Seals  50 , which may also be referred to as flowline seals, are provided about the body  40  to seal against the bore  42  of the housing  38  to inhibit fluid passing between ports  44  and  46  from leaking out of the diverter  24 . An end cap  52  houses components of the annular preventer (see  FIG. 12 ) and includes an opening to allow items (e.g., a casing string or a drill string) to pass through the diverter  24 . 
     Locking dogs  54  are mounted on the housing  38  and include locking elements (also referred to herein as “dogs”) that can be extended into recesses of the diverter  24  to secure the diverter within the housing and to keep the diverter seated within the housing during a pressure kick. In at least some embodiments, including that depicted in  FIGS. 3 and 4 , the locking dogs  54  include not only locking elements, but also stabs with fluid conduits that engage receptacles  56  within recesses of the diverter  24  to provide control fluid (e.g., hydraulic control fluid) that enables control of certain functions (e.g., hydraulic functions) of the diverter  24 . Such functions could include closing the annular preventer of the diverter  24 , opening the annular preventer, and energizing the flowline seals  50  to name several examples, although the diverter  24  could have other or additional functions implemented with control fluid provided through the locking dogs  54  in other embodiments. The term “stabbing dog” is used herein to mean a locking dog having both a locking element and a stab for conveying control fluid to the diverter  24 . Thus, the locking dogs  54  in  FIGS. 3 and 4  may also be referred to herein as stabbing dogs  54 . 
     The inclusion of the fluid stabs within the locking dogs  54  allows the fluid connections to be made with the diverter in a “hands-free” manner, in contrast to some previous systems in which a user manually connects separate, hard-to-access fluid connections to the diverter (e.g., while suspended below the drill floor over a moon pool). The integration of the fluid stabs in the locking dogs  54  also reduces the number of separate connections, which may simplify installation of a diverter and reduce alignment issues between the diverter and the housing. And while the presently disclosed stabbing dogs  54  are described herein as being used for retaining and making fluid connections with a diverter, the stabbing dogs  54  could also be used in other applications. That is, the stabbing dogs  54  could also or instead be used to engage and make fluid connections with other components (besides a diverter) in full accordance with the present techniques. 
     The receptacles  56  may be radially aligned with the stabbing dogs  54  with a keyed arrangement (such as the key on the left side of bore  42  in  FIG. 3 ) and vertically aligned by the engagement of mating shoulders of the body  40  (above the fluid ports  44  in  FIG. 3 ) and the bore  42  (below the stabbing dogs  54 ). The housing  38  may also include a connection plate  58  with various fittings for routing control fluid through hoses or pipes into the stabbing dogs  54  and the diverter  24 . 
     A block diagram generally illustrating fluid connections among the locking dogs  54 , the diverter  24 , and a diverter control unit  60  is depicted in  FIG. 5  in accordance with one embodiment. In this example, the diverter control unit  60  provides control fluid to the locking dogs  54 . The diverter control unit  60  can include any suitable components, such as a computer system (e.g., with a processor and memory having stored instructions for carrying out the control functions described herein) and a pump for outputting control fluid to the locking dogs  54 . Individual locking dogs  54  are here denoted by reference numerals  62 ,  64 ,  66 , and  68 , and the locking dogs  54  are connected to provide control fluid to the flowline seals  50  and an annular preventer  70  of the diverter  24 . 
     More specifically, as presently depicted, the locking dogs  62 ,  64 , and  66  are connected to the diverter control unit  60  by fluid lines  72 ,  74 , and  76 . In at least some embodiments, the locking dogs  54  are hydraulically actuated. That is, hydraulic control fluid is pumped into the locking dogs  54  to extend and retract their locking elements. Accordingly, each set of fluid lines  72 ,  74 , and  76  in  FIG. 5  includes two lines for that purpose. The third line of each set represents a fluid line for routing control fluid through the locking dogs and into the diverter  24  (via fluid connections  78 ,  80 , and  82 ) to control operating functions of the diverter. For instance, fluid may be pumped through the locking dog  62  and the fluid connection  78  to open the annular preventer  70 , through the locking dog  64  and the fluid connection  80  to close the annular preventer  70 , and through the locking dog  66  and the fluid connection  82  to energize the flowline seals  50 . Fluid lines  84  connect the diverter control unit  60  to the locking dog  68  and include two lines to hydraulically control the extension and retraction of its locking element, as described above for the other locking dogs. In the embodiment of  FIG. 5 , the locking dog  68  does not provide control fluid to the diverter  24 . But in other embodiments, the locking dog  68  could enable control of a diverter function by providing such control fluid through an integrated stab. 
     A locking dog  54  is depicted in  FIGS. 6 and 7  in accordance with one embodiment. The locking dog  54  in this example includes a locking element or dog  90  installed in a housing  92 . The dog  90  can be extended from the housing  92  to engage a recess in the diverter  24  to retain the diverter  24  within the diverter housing  38  (e.g., during a pressure kick). The locking dog housing  92  includes mounting holes  94  to allow the locking dog  54  to be fastened to the diverter housing  38 . The locking dog  54  of this example also includes a male fluid stab  96  provided within the dog  90  for conveying fluid to the diverter  24 ; accordingly, this locking dog  54  may also be considered to be a stabbing dog  54 . A back plate  98  is provided to retain the dog  90  in the housing  92  and can be fastened to the housing  92  via mounting holes  100 . A cylinder cap  102  is similarly provided to retain the stab  96  (as well as other components described below) within the dog  90 . The cylinder cap  102  can be threaded into the end of the dog  90  or attached in any other suitable manner. In the present embodiment, the dog  90  is a linear actuator (e.g., a hydraulic cylinder) that extends and retracts in response to pressure applied via fluid port  104  (to extend) and fluid port  106  (to retract). The housing also includes ports  108  and  110  to enable fluid for controlling the extension and retraction of the dog  90  to be routed through the locking dog  54  to another locking dog  54  (e.g., to facilitate synchronous operation of multiple locking dogs  54 ). 
     An example of a female receptacle  56  for engaging the locking dog  54  is depicted in  FIG. 8  as being removed from the diverter  24  for the sake of explanation. The receptacle  56  includes a mounting plate  116  with holes  118  to allow the receptacle to be fastened into a recess of the diverter, as generally depicted in  FIGS. 3 and 4 . The receptacle  56  includes a plug portion  120  with seal grooves  122  for holding seals (not shown in this figure) to engage the recess into which the receptacle  56  is installed. The receptacle  56  is also depicted as including a cylindrical receiving portion  124 . When the dog  90  is extended from the housing  92  toward the receptacle  56 , the dog  90  is received about the outside of the cylindrical receiving portion  124  while the stab  96  is received within the portion  124 . Fluid from the stab  96  may then be routed the receptacle  56  via ports  126  and then directed elsewhere within the diverter  24 . 
     Operation of the locking dog  54  to hold the diverter  24  within the housing  38  and to complete a fluid connection between the stab  96  and the diverter  24  may be better understood with reference to  FIGS. 9 and 10 . Particularly,  FIG. 9  depicts the receptacle  56  aligned with the locking dog  54  (having a retracted dog  90 ) when the diverter  24  is installed in the housing  38 , while  FIG. 10  depicts extension of the dog  90  and the stab  96  to engage the receptacle  56 . In the illustrated embodiment, the locking dog  54  includes a spacer  130  disposed between the dog  90  and the stab  96 , as well as a spacer sleeve  132  disposed about a shoulder  134  of the stab  96 . The spacer  130  has an inner diameter that is larger than the outer diameter of the stab  96  such that the spacer  130  is spaced apart from the stab  96 . This gives the stab  96  radial freedom of movement within the spacer  130 . And in conjunction with the spacer sleeve  132 , this also allows the stab  96  enough space to “float” within the dog  90  to self-align with the receptacle  56  during extension of the dog  90 . Such floating of the stab  96  may also account for tolerance stack-ups while keeping a sealed connection. A rear wiper ring  136  is provided inside the cylinder cap  102  to provide a wiper function for the stab  96  and the spacer  130 . It is also noted that the back plate  98  can provide bearing support, sealing, and wiper functions for the extendable dog  90 . 
     Fluid may be pumped into the locking dog  54  (e.g., via port  104 ) to extend the dog  90  into a recess  142  in which the receptacle  56  is installed. As generally noted above, the plug portion  120  of the receptacle can include seals that seal against a surface  144  of the recess  142  to inhibit fluid passing through the stab  96  (via ports  150 ) and the fluid ports  126  from leaking out of the recess. As the dog  90  is extended from the position shown in  FIG. 9  to that shown in  FIG. 10 , an angled lead-in ring  152  facilitates alignment of the stab  96  with the receptacle  56 . Seals  154  and a spacer cage  156  are provided within the receptacle  56  and are retained by the lead-in ring  152 . The seals  154  (e.g., elastomeric seals) receive and seal against the stab  96 , and the ports  150  of the stab  96  are positioned between the seals  154  opposite the spacer cage  156 . This allows control fluid to be routed through the stab  96  (e.g., from a hose connected to fitting  160  on one end of the stab), out the ports  150 , through openings  158  in the spacer cage  156  to fluid conduits  126 , and from these fluid conduits  126  to a fluid conduit (e.g., fluid conduit  162 ) leading from the recess  142  to another portion of the diverter  24 . 
     Although fluid connections to the locking dogs  54  could be made in any suitable way, in some embodiments fluid lines to the locking dogs  54  are generally provided on the connection plate  58 . One example of such an arrangement is shown in  FIG. 11 . In this embodiment, and as previously depicted in  FIG. 5 , the locking dogs  54  include individual locking dogs  62 ,  64 ,  66 , and  68 . A hose  170  connects the stab  96  of the locking dog  62  to a fitting  172  on the connection plate  58  to allow control fluid to be routed from the fitting  172 , through the hose  170  and the stab  96  of the locking dog  62 , and into the diverter  24  to control an operational aspect of the diverter (e.g., opening the annular preventer  70 ). Hoses  174  and  178  are similarly connected (that is, between respective stabs  96  of the locking dogs  64  and  66  and fittings  176  and  180  of the connection plate  58 ) to provide control fluid into the diverter  24  to control operational aspects (e.g., closing the annular preventer  70  and energizing flowline seals  50 ). 
     The locking elements of the locking dogs  62 ,  64 ,  66 , and  68  may be extended and retracted in the manner generally described above, and piping  184  and  186  is connected to various ports (e.g., via fittings on ports  104 ,  106 ,  108 , and  110  of  FIGS. 6 and 7 ) of the locking dogs to enable actuation of their locking elements. Particularly, in the present embodiment, hydraulic control fluid can be routed from a fitting  188  on the connection plate  58  to the locking dogs through piping  184  to extend the locking elements and engage the diverter  24 . Conversely, hydraulic control fluid can be routed from a fitting  190  on the connection plate  58  to retract the locking elements and release the diverter  24 . In at least one embodiment, the diverter control unit  60  ( FIG. 5 ) is connected in fluid communication with the various fittings on the connection plate  58  to enable the diverter control unit  60  to pump control fluid through the hoses and piping discussed above via the fittings. For example, the fittings  172 ,  176 ,  180 ,  188 , and  190  can be connected to ports through the connection plate  58  and hoses or pipes from the diverter control unit  60  can be connected to the ports on the underside of the connection plate  58  to enable fluid from the diverter control unit to be pumped into the diverter  24  via the stabbing dogs  54 . 
     Certain examples showing the locking dogs  54  as placed in fluid communication with conduits in the diverter  24  to control operational aspects of the diverter are provided in  FIGS. 12-14 . More specifically, the example depicted in  FIGS. 12 and 13  generally shows that the annular preventer  70  of the diverter  24  can be closed and opened with fluid from the locking dogs  62  and  64 , and the example depicted in  FIG. 14  shows that the flowline seals  50  can be energized with fluid from the locking dog  66 , as generally described above with respect to  FIG. 5 . But while these specific examples are provided for explanatory purposes, it will be appreciated that other operational aspects could also or instead be controlled via fluid routed through one or more locking dogs  54 . 
     In  FIGS. 12 and 13 , the locking dog  62  (through extension of its locking element  90 ) engages a mating receptacle  56  to place the stab  96  of the locking dog  62  in fluid communication with the conduit  162  in the diverter  24 . In a similar manner, the locking dog  64  engages a mating receptacle  56  to place its stab  96  in fluid communication with a conduit  196  in the diverter  24 . As here depicted, the conduits  162  and  196  generally lead to the annular preventer  70 , allowing control fluid (e.g., hydraulic fluid) to be routed to the annular preventer  70  to control opening and closing of the annular preventer  70  to selectively inhibit fluid from passing to the drilling rig through the diverter  24 . The annular preventer  70  can seal about a member  202  (e.g., a drill string) extending through a bore  204  of the diverter  24 . Or, in some instances, the annular preventer  70  could also or instead be adapted to seal an open bore  204  without such a member  202 . 
     The annular preventer  70  includes a piston  208  configured to move along a spacer  210 . To close the annular preventer  70 , control fluid is pumped into the stab  96  of the locking dog  64  (e.g., from hose  174  of  FIG. 11 ) and this control fluid is routed through the receptacle  56  and the fluid conduit  196  to drive the piston  208  upward from the position depicted in  FIG. 12  to that depicted in  FIG. 13 . As the piston  208  is driven upward, a plunger  212  connected to the piston  208  is driven into and compresses an element  214 . This, in turn, causes the compressed element  214  to move radially inward, which also pushes a packer  216  (or other sealing element) into sealing engagement within the diverter  24  (e.g., about the drill string or other member  202 ) to inhibit fluid flow through the diverter  24  to the drilling rig. The annular preventer  70  also includes a retaining ring  218  to retain the packer  216  within the end cap  52 . The annular preventer  70  can be opened by pumping control fluid into the stab  96  of the locking dog  62  (e.g., from hose  170  of  FIG. 11 ). The fluid pumped into the locking dog  62  can be routed through conduit  162  and through fluid ports  222  in the piston  208  to drive the piston  208  downward (i.e., from the position in  FIG. 13  to that in  FIG. 12 ). This allows the element  214  and the packer  216  to retract outward into the space vacated by the piston  208  and the plunger  212 , thereby opening the bore  204 . 
     Turning finally to  FIG. 14 , the locking dog  66  is shown as having engaged a receptacle  56 . That is, the dog  90  of the locking dog  66  has been extended toward the receptacle  56  to hold the diverter  24  within the housing  38  and to place the stab  96  within the dog  90  in fluid communication with a conduit  226  in the diverter  24 . In operation, control fluid can be pumped into the stab  96  of the locking dog  66  (e.g., from hose  178  of  FIG. 11 ). This fluid may be conveyed through the stab  96  and the receptacle  56  to the conduit  226 , and the increased pressure within the conduit  226  applies a radially outward force against the flowline seals  50 , causing these flowline seals  50  to energize and seal against the bore  42  of the diverter housing  38 . Fluid in the conduit  226  may be pumped out through the receptacle  56  and the stab  96  to release the seals (e.g., to facilitate removal of the diverter  24  from the housing  38 ). 
     While the aspects of the present disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. But it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.