Abstract:
A method and apparatus for completing a well that includes a subsurface barrier valve utilizes an injection valve which includes a variable orifice insert. The injection valve includes a mechanism for sensing pressure cycles that are employed during various well completion operations including pressure testing. The mechanism includes an indexing sleeve which will disable pressure functionality. Once this occurs, pressure cycling to open the barrier valve can proceed. Once the barrier valve opens, flow alone controls the injection valve during normal operations.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to provisional U.S. patent application Ser. No. 62/321,557 filed Apr. 12, 2016, the entire contents of which is hereby expressly incorporated by reference thereto. 
     
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
       [0002]    This invention relates to a dual barrier pressure cycle actuated injection valve (DBPCAIV) that is used as a substitute for gas charged, deep set surface controlled subsurface safety valves currently in use for providing a safety valve in conjunction with a barrier valve in subsea oil/gas wells. 
         [0003]    The DBPCAIV is positioned adjacent a stab at the end of a tubular string for providing a flow passage in the subsea well. The DBPCAIV is designed to accommodate a plurality of pressure cycles to facilitate testing at a pressure downhole gage (PDG). 
       BRIEF SUMMARY OF THE INVENTION 
       [0004]    The DBPCAIV of the present invention includes an injection valve having a flapper closure valve at its downhole end and also includes a variable orifice insert. 
         [0005]    The DBPCAIV together with a traditional barrier valve provide a dual barrier during installation. 
         [0006]    Tubing pressure cycles close the valve and enable pressure testing at a pressure downhole gage. One or more additional pressure cycles reopen the injection valve and lock out its internal hydraulic piston. With pressure functionality disabled within the injection valve, pressure cycling that is required to open the barrier valve can proceed. When the barrier valve is opened, flow alone operates the safety valve during normal operation. 
         [0007]    The injection valve includes an upper indexing sleeve that includes a plurality of groove segments on its outer surface. A pin fixed in the injection valve housing will cause the indexing sleeve to rotate in response to pressure cycles. 
         [0008]    After a given number of pressure cycles the pin will constrain the axial movement of the indexing sleeve which in turn will lock out movement of a piston which is adapted to move a flow tube. 
         [0009]    The injection valve also includes a lower indexing sleeve which also includes a plurality of groove segments that interact with a stationary pin to rotate the lower indexing sleeve through a plurality of pressure cycles. Once the barrier valve is open, the lower indexing sleeve is axially movable to an amount sufficient to open and close the flapper valve element during flow cycles of the injection fluid. 
       BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
       [0010]    For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which: 
         [0011]      FIG. 1  is a schematic view of an injection valve according to an embodiment of the invention positioned adjacent to the polished bore receptacle of the well. 
         [0012]      FIG. 2  is a schematic of the injection valve and tubing positioned within the polished bore receptacle. 
         [0013]      FIG. 3  is schematic of the injection valve with the flapper element in a closed position with the stab sealed in the polished bore receptacle. 
         [0014]      FIG. 4  is a schematic view of the injection valve in an open position with the stab sealed in the polished bore receptacle. 
         [0015]      FIG. 5  is a schematic view of the injection valve in the open position and the barrier valve in an open position after the final barrier valve pressure cycle. 
         [0016]      FIG. 6  is a schematic view of the injection valve and barrier valve in the open position during injection fluid flow. 
         [0017]      FIG. 7  is schematic view of the injection valve in a closed position when injection fluid flow is terminated. 
         [0018]      FIG. 8  is a cross-sectional view of the injection valve according to an embodiment of the invention. 
         [0019]      FIG. 9  is a perception view of the upper indexing sleeve. 
         [0020]      FIG. 10  is a schematic depiction of the grooves located on the surface of the upper indexing sleeve. 
         [0021]      FIG. 11  is a perspective view of the lower indexing sleeve. 
         [0022]      FIG. 12  is a depiction of the grooves located on the outer surface of the lower indexing sleeve. 
         [0023]      FIG. 13  is a cross-sectional view of the injection valve as it is positioned above the polished bore receptacle as shown in  FIG. 1 . 
         [0024]      FIG. 14  is a depiction of the position of the pin within the grooves on the surface of the upper indexing sleeve in the position of the injection valve shown in  FIG. 1 . 
         [0025]      FIG. 15  is a showing of the position of the pin within the grooves of the lower indexing sleeve when the injection valve is in the position shown in  FIG. 1 . 
         [0026]      FIG. 16  is a showing of the injection valve in the position shown in  FIG. 2  with the stab sealing into the polished bore receptacle. 
         [0027]      FIG. 17  is a showing of the position of the pin within the grooves of the upper indexing sleeve when the injection valve is in the condition shown in  FIG. 16 . 
         [0028]      FIG. 18  is a showing of the position of the pin in the grooves of the lower indexing sleeve when the injection valve is in the condition shown in  FIG. 16 . 
         [0029]      FIG. 19  is a cross-sectional view of the injection valve in the position of  FIG. 3  once the tubing pressure has been bled to close the flapper valve. 
         [0030]      FIG. 20  is a showing of the position of the pin in the grooves of the upper indexing sleeve when the injection valve is in the condition shown in  FIG. 19 . 
         [0031]      FIG. 21  is a showing of the position of the pin in the grooves of the lower indexing sleeve when the injection valve is in the condition shown in  FIG. 19 . 
         [0032]      FIG. 22  is a cross-sectional view of the injection valve in the position shown in  FIG. 3  with the pressure increased. 
         [0033]      FIG. 23  is a showing of the position of the pin in the grooves of the upper indexing sleeve when the injection valve is in the condition shown in  FIG. 22 . 
         [0034]      FIG. 24  is a showing of the position of the pin in the grooves of the lower indexing sleeve when the injection valve is in the condition shown in  FIG. 22 . 
         [0035]      FIG. 25  is a cross-sectional view of the injection valve after the tubing pressure is bleed to test for pressure leak rate between the injection valve and the barrier valve. 
         [0036]      FIG. 26  is a showing of the pin in the grooves of the upper indexing sleeve when the injection valve is in the condition shown in  FIG. 25 . 
         [0037]      FIG. 27  is a showing of the pin in the groove of the lower indexing sleeve when the injection valve is in the condition shown in  FIG. 25 . 
         [0038]      FIG. 28  is a cross-sectional view of the injection valve after pressure testing and with the flapper element in an open position. 
         [0039]      FIG. 29  is a showing of the position of the pin in the grooves of the upper indexing sleeve when the injection valve is in the condition of  FIG. 28 . 
         [0040]      FIG. 30  is a showing of the position of the pin in the grooves of the lower indexing sleeve when the valve is in the condition of  FIG. 28 . 
         [0041]      FIG. 31  is a cross-sectional view of the injection valve after the flapper valve has been opened and the tubing pressure bled. 
         [0042]      FIG. 32  is a showing of the position of the pin in the grooves of the upper indexing sleeve when the valve is in the condition shown in  FIG. 31 . 
         [0043]      FIG. 33  is a showing of the position of the pin in the grooves of the lower indexing tube when the injection valve is in the condition shown in  FIG. 31 . 
         [0044]      FIG. 34  is a cross-sectional view of the injection valve during the application of pressure cycles as needed to open the barrier valve. 
         [0045]      FIG. 35  is a showing of the position of the pin in the grooves of the upper indexing sleeve when the injection valve is in the condition shown in  FIG. 34 . 
         [0046]      FIG. 36  is a showing of the position of the pin in the grooves of the lower indexing sleeve when the injection valve is in the condition shown in  FIG. 34 . 
         [0047]      FIG. 37  is a cross-sectional view of the injection valve with the flapper element in an open position. 
         [0048]      FIG. 38  is a showing of the position of the pin in the grooves of the upper indexing sleeve when the injection valve is in the condition shown in  FIG. 37 . 
         [0049]      FIG. 39  is a showing of the position of the pin the grooves of the lower indexing sleeve when the injection valve is in the condition shown in  FIG. 37 . 
         [0050]      FIG. 40  is a cross-sectional view of the injection valve when the barrier valve is in the open position and there is full flow through the variable orifice insert. 
         [0051]      FIG. 41  is a showing of the position of the pin in the grooves of the upper indexing sleeve when the injection valve is in the condition shown in  FIG. 40 . 
         [0052]      FIG. 42  is a showing of the position of the pin in the grooves of the lower indexing sleeve when the injection valve is in the condition shown in  FIG. 40 . 
         [0053]      FIG. 43  is a cross-sectional view of the injection valve with injection flow terminated. 
         [0054]      FIG. 44  is a showing of the position of the pin in the grooves of the upper indexing sleeve when the injection fluid is in the condition shown in  FIG. 43 . 
         [0055]      FIG. 45  is a showing of the position of the pin in the lower indexing sleeve when the injection vale is in the condition shown in  FIG. 43 . 
     
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0056]      FIG. 1-5  illustrates the various steps that can be taken prior to opening the barrier valve of a subsea well according to an embodiment of the invention. 
         [0057]    As shown in  FIG. 1 , a typical subsea well includes casing  1 , a tubular string  2 , a stab  3  with an annular seal  4 , a polished bore receptacle  8 , tubing hangers  5  and a barrier valve  6 . In accordance with the invention an injection valve  10  with a variable orifice insert  12  is attached to a lower end of the tubular string  2 . Injection valve  10  includes a flapper closure element  11 . The flapper element  11  is in an open position and variable orifice insert  12  is in a bypass mode to allow the injection valve to be run into the well adjacent to the polished bore receptacle as shown in  FIG. 1 . 
         [0058]      FIG. 2  illustrates the position of the injection valve with stab  3  positioned within the polished bore receptacle. Flapper element  11  is in the open position and the variable orifice insert  12  is in the bypass mode. 
         [0059]    Applying pressure to the barrier valve with the injection valve in the position and the relieving the tubing pressure will cause flapper element  11  to close as illustrated in  FIG. 3  as discussed below. In order to pressure test the injection valve and barrier valve pressure now can be increase between the two valves via the pressure testing gauge and inlet  7 , and pressure within tubing  2  is relieved. Once the dual barrier integrity is confirmed, the blowout preventer assembly can now be removed from the well head. At this point two pressure cycles have been completed. 
         [0060]    At this point by increasing tubing pressure the flapper element with open to the position shown in  FIG. 4  and when tubing pressure is relieved, the flapper element will remain open as explained below. The variable orifice insert remains open in a bypass position. Now the barrier valve can be pressure cycled as needed with the injection valve and the variable orifice valve remaining open. 
         [0061]      FIG. 5  illustrates the barrier valve in an open position after the final barrier valve pressure cycle. With the barrier valve open initial injection flow resets the variable orifice insert as explained below and flow occurs through the barrier valve as shown in  FIG. 6 . When injection fluid flow stops, flapper element  11  will move to a closed position shown in  FIG. 7 . The variable orifice insert and the injection valve will open without flapper damage and close for protection when injection stops thereby forming a dual barrier injection valve. 
         [0062]      FIG. 8  illustrates the details of an injector valve including a variable orifice insert according to an embodiment of the invention. 
         [0063]    Injector valve  15  includes a main valve housing which includes an uphole connector portion  20 , a piston housing  21  having a vent  17 , a middle portion  22  and a downhole flapper element housing  23 . Flapper element  63  is pivotably mounted by a pivot mount  62  to housing  23  in a known manner. 
         [0064]    An hydraulic piston  26  is positioned within a wall section of piston housing  21 . The uphole portion of piston  26  is exposed to pressure within connector portion  20 . The downhole portion of piston  26  abuts against a shoulder  19  on an upper indexing sleeve  24 . An upper flow tube  36  has an uphole portion  25  positioned within upper indexing sleeve  24 , and a lower portion  40  which extends within middle hosing portion  22 . Upper flow tube  36  also includes an enlarged portion  125 . Upper indexing sleeve  24  shown in  FIG. 9  is mounted for axial and rotational movement within the injection valve housing and includes a plurality of grooves section  70 - 83  as depicted in  FIG. 10 . A pin  28  fixed in housing  21  is adapted to guide axial and rotational movement of the upper indexing sleeve  24  via groove sections  70 - 83 . An annular bearing  112  is positioned between shoulder  19  and upper flow tube  36 . 
         [0065]    A variable orifice insert  112  is inserted into the injection vale housing and includes a connector portion  29 , a locking collet  38  with a plurality of radially spaced fingers  39  and an upper flow section  47  which is connected to a lower flow tube  46 . At least one magnet  44  is attached to lower flow tube  46  and at least one magnet  45  of opposite polarity is freely mounted on the lower flow tube. Magnet  45  is adapted to move with a lower flow sleeve  43  which moves axially over lower flow tube  46 . A spring  51  is positioned between magnet  45  and a stop  102  provided on lower flow tube  46  so that axial movement of lower flow sleeve  43  will compress spring  51 . Seals  111  are positioned between upper flow tube  36  and the variable orifice insert  112 . 
         [0066]    Lower flow sleeve  43  carries at its downhole end a valve body  53  supported by a plurality of struts  54 . A valve seat  55  is provided on the downhole end of lower flow tube  46  to create a variable annular orifice  115  shown in  FIG. 40 . 
         [0067]    A lower cylindrical indexing sleeve  103  shown in perspective in  FIG. 11  includes an uphole portion  105  and a downhole portion  61 . Lower indexing sleeve  103  also include a plurality of grooves  89 - 101  on its outer surface as depicted in  FIG. 12 . Lower indexing sleeve is adapted for rotational and axial movement within the injection valve housing. An annular power spring  41  surrounds the lower portion  40  of the upper flow tube  36  and the uphole portion  105  of the lower indexing sleeve as shown in  FIG. 8 . Power spring  41  is captured between upper flow tube  36  and a shoulder  104  in the interior of middle housing  22  so that as upper flow tube is moved in a downhole direction via piston  26  by pressure within the tubular string, power spring  41  is compressed. Downhole movement of section  61  of the lower indexing sleeve is constrained by a shoulder  64  pivoted in the interior surface of injection valve housing  22 . A fixed pin  110  guides movement of lower indexing sleeve  103  via grooves  91 - 101 . 
         [0068]    A plurality of locking dogs  35  cooperate with a groove  37  on the interior surface of upper flow tube  36  to lock the variable orifice insert within the injection valve. In the position shown in  FIG. 8 , lower portion  61  of the lower indexing sleeve holds flapper element  63  in an open position. A locking collet  42  is located at the lower end of lower portion  40  of the upper flow tube and is adapted to capture the lower indexing sleeve at groove  49 . 
         [0069]    The operation of the variable orifice insert including the run in position is more fully described in U.S. Patent Application Publication number 2015/0361763A1 published Dec. 17, 2015, the entire contents of which is hereby expressly incorporated herein by reference thereto. 
         [0070]      FIG. 13  illustrates the condition of the injection valve at its location in the well shown in  FIG. 1 . In this position flapper element  63  is in an open position, the variable orifice insert is in the bypass position, pin  28  of the upper indexing sleeve is within the downhole end of slot  70  as shown in  FIG. 14  and pin  110  of the lower indexing sleeve is at the top of groove  91  as shown in  FIG. 15 . 
         [0071]      FIG. 16  illustrates the condition of the injection valve shown in the position of  FIG. 2  after the tubing pressure against the barrier valve been increased. Pressure acting on piston  26  moves the piston in a downhole direction which in turn axially moves upper indexing sleeve  24 , upper flow tube  36  and variable orifice insert  13  downwardly, thereby compressing power spring  41 . Pin  28  is now located at the top of groove  72  of upper indexing sleeve as depicted in  FIG. 17  and pin  110  is positioned at the top of groove  91  of the lower indexing sleeve as shown in  FIG. 18 . The variable orifice insert is still in the bypass mode allowing limited fluid flow through annular orifice  105 . Lower portion  40  of the upper flow tube engages and captures upper portion  105  of the lower indexing sleeve at  49 . 
         [0072]      FIG. 19  illustrates the condition of the injection valve as shown in  FIG. 3  after the tubing pressure is relieved. Power spring  41  shifts upper flow tube  36 , lower flow tube  40  and the lower indexing sleeve and variable orifice insert to an uphole portion. This causes flapper element  63  to close. Pin  28  is now positioned at the bottom of groove  74  of the upper indexing sleeve and pin  110  is positioned at  89  of the lower indexing sleeve as shown in  FIGS. 20 and 21 . 
         [0073]    As pressure within the tubing is increased to do pressure testing, the piston  26 , upper flow tube  36 , upper and lower indexing sleeves well be moved downwardly a short distance as shown in  FIG. 22  and as illustrated by the pin  28  being positioned at  76  in the upper indexing sleeve as shown in  FIG. 23 . Pin  28  thus restricts further downward movement of upper indexing sleeve  24 . Pin  110  is located at position  89  shown in  FIG. 24 . Power spring  41  has been compressed a limited amount. Flapper valve  63  remains closed. 
         [0074]    At this point pressure within the tubing is relieved so that the injection valve is now in the position shown in  FIG. 25 . Pressure can be applied between the injection valve and the barrier valve through pressure downhole gauge  7  for testing purposes. Any leak rate is monitored. In this position flapper element  63  is closed as is barrier valve  6 . Pin  28  is positioned at  77  of the upper indexing sleeve as shown in  FIG. 26  and pin  110  is located at position  89  of the lower indexing sleeve as shown in  FIG. 27 . Power spring  41  has moved the piston, upper and lower indexing sleeves, the upper flow tube and the variable orifice insert to the position shown in  FIG. 25 . If the pressure testing is successful, the blowout preventer at the well head may now be removed. 
         [0075]    At this point in the well completion process, tubing pressure can be increase and flapper element  63  will be opened as shown in  FIG. 28  by virtue of piston  26  moving downhole thereby axially moving upper indexing sleeve  24 , flow tube  36  and lower indexing sleeve  103 . Lower portion  61  of the lower indexing sleeve  13  will pivot flapper element  63  to an open position. 
         [0076]    In this state of operation, pin  28  will be at location  80  of the upper indexing sleeve as shown in  FIG. 29  and pin  110  will be at location  95  of the lower indexing sleeve as shown in  FIG. 30 . 
         [0077]    At this point pressure within the tubing can be relieved and the injection valve will revert back to the condition of  FIG. 31 . Power spring acts on upper flow tube  36 , upper indexing sleeve  24  and piston  26  to move them to the position shown in  FIG. 31 . Pin  28  is positioned at location  82  of the upper indexing sleeve as shown in  FIG. 32  and pin  110  of the lower indexing sleeve is at position  97  as shown in  FIG. 33 . 
         [0078]    As pressure cycles are applied to the injection valve, in the condition of  FIG. 31  as required to open the barrier valve, upper indexing sleeve&#39;s axial movement is limited by end points  81  and  82  as shown in  FIG. 35  which limits the movement of piston  26 . Consequently flapper element  63  remains in an open position as shown in  FIG. 34 . Pin  110  is located at position  97  of the lower indexing sleeve as shown in  FIG. 36 . 
         [0079]    When the barrier valves is opened and flow occurs, piston  28 , upper indexing sleeve  24  and upper flow tube  36  will be returned to position shown in  FIG. 37 . Pin  28  is at position  82  of the upper indexing sleeve as shown in  FIG. 38  and pin  110  remains at position  97  of the lower indexing sleeve as shown in  FIG. 39 . 
         [0080]    Full flow is now possible through the injection valve and the barrier as shown in  FIG. 40 . Flapper element  63  has been moved to a fully open position by lower portion  61  of the lower indexing sleeve and valve body  53  has been axially displaced from valve seat  55  by the full flow thereby creating annular orifice  105 . Spring  51  is compressed by axially movement of lower flow sleeve  43 . The force of the full flow through the injection valve is sufficient to overcome the attractive force between magnets  44  and  45  and the force necessary to compress spring  51 . Power spring  41  is also compressed by the force of injection fluid acting on upper flow tube at  36 . Downhole movement of upper indexing sleeve  24  is prohibited by pin  28  engaging the top portion  81  of the groove in the outer surface of upper indexing sleeve  24  as shown in  FIG. 41 . Lower indexing sleeve has moved in a downhole direction to a point where further movement is blocked by pin  110  engaging the groove on the outer surface of the lower indexing sleeve at  100 , as shown in  FIG. 42 . 
         [0081]    Stopping the flow of injection fluid will result in the injection valve moving to the condition shown in  FIG. 43 . Power spring  41  shifts upper flow tube  36  in an uphole direction and upper flow tube  36  through locking collet  42  in groove  49  of the lower indexing sleeve carriers with it lower portion  61  of the lower indexing sleeve  103  to the position shown in  FIG. 43 . Flapper  63  is resiliently biased to a closed position as is well known in the art and thus will pivot to engage valve seat  111  thus preventing uphole fluid flow. 
         [0082]    Spring  51  and magnets  44 ,  45  will move lower flow sleeve  43  and valve body  53  in an uphole direction to engage valve seat  55  thereby forming a second valve which prevents uphole fluid flow. Thus a dual barrier safety valve is formed. 
         [0083]    Pin  28  is located at position  82  of the upper indexing sleeve as shown in  FIG. 44  and pin  110  is positioned at point  101  in the lower indexing sleeve as shown in  FIG. 45 . 
         [0084]    If injection fluid flow is restarted, the injection valve will assume the full flow condition shown in  FIG. 40  with the travel of the upper indexing sleeve limited by the distance between points  81  and  82  as shown in  FIG. 41  and lower flow tube can move axially between point  100  and  101  as shown in  FIG. 45 . In this manner, injection fluid flow may be started and stopped an unlimited number of times. Once the drilling blow out preventer is removed, a production tree is installed on the well. The barrier valve can now be cycled permanently open thereby activating the injection valve. When this occurs, dual barriers are maintained by the injection valve and the production tree. 
         [0085]    The spring constants for springs  41  and  51  are chosen such that upper flow tube  36  will move to open the flapper valve at a first pressure level and an increased flow pressure will open the variable annular orifice  115 . 
         [0086]    Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the spirit and scope of the invention as defined by the appended claims.