Abstract:
A large bore hot stab connection is configured to minimize hydraulic fluid loss and to simply connect two fluid conduits by a substantially straight push, locking the connection into place with a relatively simple turn. In general, installation of a large bore hot stab connection is performed by inserting a hot stab into a receptacle and, if present, rotating a handle to lock the hot stab into the receptacle. As both the receptacle and hot stab comprise bodies comprising an in-line check valve cartridge valve, when inserted and coupled with the receptacle the hot stab completes a low leak hydraulic subsea connection.

Description:
FIELD OF THE INVENTION 
       [0001]    Hot stab connections may be used to minimize hydraulic fluid loss and/or to simply connect two fluid conduits, such as subsea. 
       BACKGROUND 
       [0002]    A large bore hot stab with low leakage may be used to connect fluid conduits such as subsea and minimize environmental discharge of hydraulic fluid. These may be used in the offshore oil and gas market such as use as connectors for making hydraulic connections to subsea equipment, overriding existing subsea systems, and/or hydraulically operating subsea tools. 
     
    
     
       FIGURES 
         [0003]    Various figures are included herein which illustrate aspects of embodiments of the disclosed inventions. 
           [0004]      FIG. 1  is a schematic view in partial perspective of an exemplary embodiment of a large bore hot stab connection system; 
           [0005]      FIGS. 2-3  are schematic views of exemplary large bore hot stab connection receptacles; 
           [0006]      FIG. 4  is an exploded view in partial perspective of an exemplary large bore hot stab connection receptacle; 
           [0007]      FIGS. 5-6  are schematic views of exemplary large bore hot stab connection hot stabs; and 
           [0008]      FIG. 7  is an exploded view in partial perspective of an exemplary large bore hot stab connection hot stab. 
       
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
       [0009]    Referring to  FIG. 1 , in an embodiment large bore hot stab connection  100  comprises receptacle  1  and hot stab  2 . 
         [0010]    Referring additionally to  FIGS. 2-3 , receptacle  1  comprises first body  10  and first in-line cartridge check valve  30  disposed within body  10 . 
         [0011]    First body  10  comprises first large bore fluid conduit  12  therethrough, where first body  10  further comprises first mating end  15  as well as first fluid inlet  13  and first fluid outlet  11  located at opposing ends of first large bore fluid conduit  12 . First fluid inlet  13  is typically disposed proximate first mating end  15 . 
         [0012]    In currently contemplated embodiments, receptacle  1  may further comprise one or more seal areas  17  disposed within or about body  10 . These seal areas  17  are generally placed inside first large bore fluid conduit  12  or near first fluid inlet  13  where they can protect against mechanical damage. 
         [0013]    First in-line cartridge check valve  30  is adapted to be removably insertable into body  10 , is in fluid communication with first large bore fluid conduit  12 , and is configured to allow unidirectional fluid flow within first large bore fluid conduit  12 . 
         [0014]    Referring now to  FIG. 4 , in certain embodiments, receptacle  1  further comprises flange  102 , which may comprise a manifold, disposed proximate an end of first body  10  where first fluid outlet  11  is located. Flange  102  may be welded to first body  10  or, alternatively, fastened to first body  10  such as by using one or more fasteners  101  which are dimensioned to be securely received into corresponding fastener bores  105   a  in first body  10 . One or more seals  103 , e.g. O-rings or the like, may be present and disposed intermediate flange  102  and first body  10 . 
         [0015]    First body  10  may further comprise latch receiver  104  which, in currently contemplated embodiments, comprises two or more latch receivers  104 , which may be a J-lock, dimensioned to allow hot stab  2  ( FIG. 1 ) to be selectively, removably secured to first body  10 . Each such latch receiver  104  may be a separate piece removably secured to first body  10  such as by latch fasteners  105  which are dimensioned to be securely received into first body  10 , e.g. into latch fastener bores  105   a . In these embodiments, each latch receiver  104  which is secured to first body  10  comprises latch fastener bore  104   a  through which latch fasteners  105  are received. In addition, spring ball nose  106  may be used to help handle  24  stay latching in the lock position in latch receiver  104 . 
         [0016]    Referring now generally to  FIGS. 5-6 , hot stab  2  comprises second body  20 ; handle  24  disposed about outer surface  26  of second body  20 ; and second inline cartridge check valve  32  oriented in the same flow direction as first in-line cartridge check valve  30 . 
         [0017]    Second body  20  comprises mating end  23  adapted to be cooperatively receive first mating end  15 ; second fluid conduit  22 , comprising second fluid inlet  23 , disposed proximate mating end  23 , and first fluid outlet  21  disposed opposite second fluid inlet  23 . 
         [0018]    Second in-line cartridge check valve  32  is typically dimensioned to be removably insertable into second body  20 , e.g. within second large bore fluid conduit  22 , and allow unidirectional fluid flow within first large bore fluid conduit  22 . 
         [0019]    A hot stab locking mechanism may be present and used to allow and/or prevent disengagement during operations. In certain embodiments, a hot stab handle such as handle  24  is adapted to be compatible with a remotely operated vehicle (ROV), e.g. ROV  50  ( FIG. 1 ), e.g. using ROV manipulator  52 . Handle  24  may comprise one or more latches  28 , one or more of such latches  28  being dimensioned to be selectively received into a corresponding latch receiver  104  ( FIG. 1 ). In alternative embodiments, one or more latches  28  may be part of second body  20 . 
         [0020]    Further, in certain embodiments handle  24  is dimensioned to snugly fit about an outer surface of second body  20 . In other embodiments, handle  24  comprises two or more handles  24  which may be snugly fit about an outer surface of second body  20  and which may be secured to each other or to second body  20  using one or more handle fasteners  29   a.    
         [0021]    Referring additionally to  FIG. 7 , end cap  26  may be present to selectively secure second in-line cartridge check valve  32  within second body  20  such as by using one or more end cap fasteners  26   a  dimensioned to be received through bores  26   b  in end cap  26  and secured into corresponding end cap fastener bores  26   b  in second body  20 . End cap seal  27  may be disposed intermediate end cap  26  and second in-line cartridge check valve  32 . 
         [0022]    In certain embodiments, one or more of in-line cartridge check valve  30  and/or second inline cartridge check valve  32  may be a dual acting check valve. 
         [0023]    In the operation of exemplary embodiments, referring generally back to  FIG. 1 , large bore hot stab connection  100  is usable for subsea connection of, e.g., hydraulic lines  110 , 120 , carrying various hydraulic fluids or similar viscosity fluids and limits the amount of fluid spillage upon disconnection. Referring generally to  FIG. 1 , two fluid conduits  110 , 120  may be connected, e.g. subsea, by installing first in-line cartridge check valve  30  into receptacle  1 , where receptacle  1  is as described above and first fluid conduit  110  is connected to receptacle  1 . Second in-line cartridge check valve  32  is installed into hot stab  2 , where hot stab  2  is as described above. Either or both of first in-line cartridge check valve  30  and second in-line cartridge check valve  32  may be installed into their respective bodies  10 , 20  prior to deployment. Generally, as will be apparent to those of ordinary skill in connection arts, first in-line cartridge check valve  30  and second in-line cartridge check valve  32  are typically urged into a closed position such as by a spring until sufficient fluid pressure exists to urge the valves into their open position, thereby allowing fluid flow. In alternative embodiments, dual acting check valves  30 , 32  may be used that can open/check in both directions. 
         [0024]    Second fluid conduit  120  is connected to hot stab  2  and hot stab  2  inserted into receptacle  1 . Handle  24  may then be rotated in a first predetermined direction to lock hot stab  2  into receptacle  1  such as by securing one or more latches  28  into corresponding latch receivers  104 . After hot stab  2  is locked into receptacle  1 , fluid pressure in the upstream fluid conduit can be allowed to achieve a pressure level sufficient to open both first in-line cartridge check valve  30  and second in-line cartridge check valve  32 . 
         [0025]    The two cartridge check valves,  30  and  32 , may be replaced as needed, e.g. if damaged, malfunctioning, or different cracking pressures are required. When and if needed, hot stab  2  may be rotated in a direction until hot stab  2  is disengaged from receptacle  1  and hot stab  2  then removed from receptacle  1 . Before or after hot stab  2  is removed from receptacle  1 , fluid pressure in the conduits can be to fall below the level sufficient to open both first in-line cartridge check valve  30  and second in-line cartridge check valve  32 , allowing one or both of first in-line cartridge check valve  30  and second in-line cartridge check valve  32  to close. In addition, the flow direction of check valves  30 , 32  can be switched to allow flow in an opposite direction. Typically, however, both check valves  30 , 32  will need to be switched and allowing fluid flow in the same direction. 
         [0026]    Once hot stab  2  is removed from receptacle  1 , either or both of first in-line cartridge check valve  30  and second in-line cartridge check valve  32  may be replaced in their respective bodies  10 , 20 . Once the desired check valves  30 , 32  are replaced, hot stab  2  is reinserted into receptacle  1 , after which hot stab  2  may be rotated until hot stab  2  is secured into receptacle  1  such as by securing one or more latches  28  into corresponding latch receivers  104 . After hot stab  2  is locked into receptacle  1 , fluid pressure in the upstream fluid conduit can again be allowed to achieve a pressure level sufficient to open both first in-line cartridge check valve  30  and second in-line cartridge check valve  32 . 
         [0027]    Where handle  24  is adapted to be manipulated by ROV  50 , ROV  50  may be used to position hot stab  2  proximate receptacle  1 , insert hot stab  2  into receptacle  1 , and rotate hot stab  2  until hot stab  2  is secured into receptacle  1  such as by securing one or more latches  28  into corresponding latch receivers  104 . 
         [0028]    The foregoing disclosure and description of the inventions are illustrative and explanatory. Various changes in the size, shape, and materials, as well as in the details of the illustrative construction and/or an illustrative method may be made without departing from the spirit of the invention.