The multiple interventionless actuated downhole valve includes a valve movable between an open and a closed position to control communication between an annular region surrounding the valve and an internal bore and more specifically controlling communication between above and below the valve, and at least two remotely operated interventionless actuators in operational connection with the valve, wherein each of the interventionless actuators may be operated independently by absolute tubing pressure, absolute annulus pressure, differential pressure from the tubing to the annulus, differential pressure between the annulus and the tubing, tubing or annulus multiple pressure cycles, pressure pulses, acoustic telemetry, electromagnetic telemetry or other types of wireless telemetry to change the position of the valve and allowing the valve to be continually operated by mechanical apparatus.

RELATED APPLICATIONS  
       [0001]    This application claims the benefit of priority under 35 U.S.C. §119 of U.S. Provisional Application Serial No. 60/399,987, filed Jul. 31, 2002 and entitled ACTUATOR AND METHOD, which is incorporated by reference herein. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates in general to actuation of valves and isolation of sections of a borehole and more specifically to an apparatus and method for actuating a downhole valve more than once without physical intervention.  
         BACKGROUND  
         [0003]    In drilling operations it is common practice to include one or more valves connected within a pipe string to separate and control the flow of fluid between various sections of the wellbore. These valves are commonly referred to as formation isolation valves (FIV). The formation isolation valve can be constructed in numerous manners including, but not limited to, ball valves, discs, flappers and sleeves. These valves are primarily operated between an open and closed position through physical intervention, i.e. running a tool through the valve to open. To close the valve the tool string and a shifting tool are withdrawn through the formation isolation valve. The shifting tool engages a valve operator that is coupled to the valve moving the valve between the open and closed position.  
           [0004]    It is often desired to open the FIV without physical intervention after the valve has been closed by physical intervention, such as by running a shifting tool through the FIV via a wireline, slickline, coil tubing or other tool string. Therefore, it has been shown to provide an interventionless apparatus and method for opening the FIV a single time remotely from the surface. Interventionless is defined to include apparatus and methods of actuating a downhole valve without the running of physical equipment through and/or to the operational valve. Apparatus and methods of interventionlessly operating a downhole valve a single time are described and claimed by the commonly owned United States Patents to Dinesh Patel. These patents include, U.S. Pat. Nos. 6,550,541; 6,516,886; 6,352,119; 6,041,864; 6,085,845, 6,230,807, 5,950,733; and 5,810,087, each of which is incorporated herein by reference.  
           [0005]    Some well operations require multiple interventionless openings of the FIV. For example, opening the FIV after setting a packer, pressure testing of the tubing, perforating, flowing of a well for cleaning, and shutting in a well for a period of time.  
           [0006]    Heretofore, there has only been the ability to actuate a FIV remotely and interventionlessly once. Therefore, the interventionless actuator can only be utilized after one operation. Further, if the single interventionless actuator fails it is required to go into the wellbore with a physical intervention to open the FIV. This inflexibility to remotely and interventionlessly open the FIV more than once or upon a failure can be catastrophic. In particular in high pressure, high temperature wells, deep water sites, remote sites and rigless completions wherein intervention with a wireline, slickline, or coiled tubing is cost prohibitive.  
           [0007]    It is therefore a desire to provide a multiple, interventionless actuated downhole valve. It is a further desire to provide a multiple, interventionless actuated downhole valve wherein each actuating mechanism operates independently from other included interventionless actuating mechanisms.  
         SUMMARY OF THE INVENTION  
         [0008]    In view of the foregoing and other considerations, the present invention relates to remote interventionless actuating of a downhole valve.  
           [0009]    It is a benefit of the present invention to provide a method and apparatus that provides multiple mechanisms for opening a downhole valve without the need for a trip downhole to operate the valve.  
           [0010]    It is a further benefit of the present invention to provide redundant mechanisms for interventionlessly opening a downhole valve if initial attempts to interventionlessly open the valve fail.  
           [0011]    Accordingly, a interventionless actuated downhole valve and method is provided that permits multiple openings of a downhole valve without the need for a trip downhole to open the valve. The multiple interventionless actuated downhole valve includes a valve movable between an open and a closed position to control communication between an annular region surrounding the valve and an internal bore and more specifically controlling communication between above and below the valve, and at least two remotely operated interventionless actuators in operational connection with the valve, wherein each of the interventionless actuators may be operated independently by absolute tubing pressure, absolute annulus pressure, differential pressure from the tubing to the annulus, differential pressure between the annulus and the tubing, tubing or annulus multiple pressure cycles, pressure pulses, acoustic telemetry, electromagnetic telemetry or other types of wireless telemetry to change the position of the valve and allowing the valve to be continually operated by mechanical apparatus.  
           [0012]    The present invention includes at least two interventionless actuators but may include more. Each of the interventionless actuators may be actuated in the same manner or in differing manners. It is desired to ensure that only one interventionless actuator is operated at a time.  
           [0013]    In a preferred embodiment increasing pressure within the internal bore above a threshold pressure operates at least one of the interventionless actuators. In another preferred embodiment an interventionless actuator is operated by a differential pressure between the internal bore and the annular region.  
           [0014]    It should be recognized that varying types of interventionless actuators may be utilized. Some of the possible interventionless actuators are described in U.S. Pat. Nos. 6,550,541; 6,516,886; 6,352,119; 6,041,864; 6,085,845, 6,230,807, 5,950,733; and 5,810,087, all to Patel, each of which is incorporated herein by reference.  
           [0015]    The downhole valve has been described as a ball valve, however, other types of valves may be used, such as but not limited to flappers, sleeves, and discs, holding pressure in one direction or both directions. An example of a flapper valve is disclosed in U.S. Pat. No. 6,328,109 to Patel, and is incorporated herein by reference.  
           [0016]    The foregoing has outlined the features and technical advantages of the present invention in order that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    The foregoing and other features and aspects of the present invention will be best understood with reference to the following detailed description of a specific embodiment of the invention, when read in conjunction with the accompanying drawings, wherein:  
         [0018]    [0018]FIG. 1 is an illustration of a wellbore including a downhole valve having multiple, interventionless actuators of the present invention;  
         [0019]    [0019]FIGS. 2 a ,  2   b ,  2   c , and  2   d  show a preferred embodiment of the multiple interventionless actuator downhole valve of the present invention; and  
         [0020]    [0020]FIG. 3 is an illustration of a rupture disc assembly of the present invention.  
     
    
     DETAILED DESCRIPTION  
       [0021]    Refer now to the drawings wherein depicted elements are not necessarily shown to scale and wherein like or similar elements are designated by the same reference numeral through the several views.  
         [0022]    [0022]FIG. 1 is an illustration of a wellbore including a downhole valve having multiple interventionless actuators. In FIG. 1 a wellbore  10  having a vertical section and a deviated section is shown. Casing  12  is cemented within at least a portion of wellbore  10 . A production string  14  carrying a downhole valve  16 , shown as a formation isolation valve (FIV), is positioned within wellbore  10 . In one embodiment, FIV  16  includes a ball valve  16   a . Production string  14  and FIV  16  include an internal bore  18 . An annulus  20  is formed outside of FIV  16  that is subject to a pressure outside of the bore  18 .  
         [0023]    A tool  22 , such as a perforating gun, may be run on a tool string  24 , such as coiled tubing, through bore  18  of string  14  and FIV  16 . As and example a shifting tool  26  is connected to a bottom end of tool string  24 . Shifting tool  26  may be utilized singular or in combination with other tools  22 , such as in a sand control application the FIV may be run in the lower completion below or above a screen hanger packer. Shifting tool  26  may be used repeatedly to open and close valve  16   a  by running shifting tool  26  through FIV  16 . This is a physical, or intervention actuation of valve  16   a.    
         [0024]    FIV  16  may be actuated from the closed position to an open position by more than one interventionless actuator  28 . Interventionless actuators  28  allow an operator to open valve  16   a  without running into wellbore  10  with a shifting tool  26 , thus saving a trip downhole and great expense. As shown in FIG. 1, FIV includes two interventionless actuators  28   a  and  28   b . Each interventionless actuator  28  is independent of the other interventionless actuator  28 . Therefore, it is possible to open FIV  16  more than once without physical intervention. Additionally, multiple interventionless actuators  28  provide redundancy in case an interventionless actuator  28  fails.  
         [0025]    Referring to FIGS. 2 a ,  2   b ,  2   c , and  2   d , a preferred embodiment of the multiple interventionless actuator downhole valve of the present invention is shown. FIGS. 2 a  and  2   b  illustrate a first interventionless actuator  28   a . FIGS. 2 b  and  2   c  illustrate a second interventionless actuator  28   b . FIGS. 2 c  and  2   d  illustrate a downhole valve  16 .  
         [0026]    With reference to FIGS. 2 c  and  2   d  downhole formation isolation valve  16  is shown. In a preferred embodiment valve  16  includes a ball valve  16   a  that is movable between an open and closed position. Valve  16  includes an operating mandrel  30  functionally connected to ball valve  16   a  for moving ball valve  16   a  between the open and closed positions. Operating mandrel  30  includes a shoulder  32 .  
         [0027]    Referring to FIGS. 2 a  and  2   b  a first interventionless actuator  28   a  is shown. Interventionless actuator  28   a  is an absolute pressure actuator having a housing  34  and first actuator power mandrel  36 . Actuator  28   a  includes a first atmospheric pressure chamber  38  and a second atmospheric pressure chamber  40  separated by a seal  42 . A rupture disc assembly  44  is in communication with bore  18  and first atmospheric pressure chamber  38  via a conduit  46 .  
         [0028]    Rupture disc assembly  44  is described with reference to FIG. 3. Rupture disc assembly  44  includes a tangential port  48  in communication with inside bore  18  and conduit  46 . A rupture disc  50  is positioned between bore  18  and conduit  46 . Therefore, when the inside pressure in bore  18  exceeds a predetermined threshold, rupture disc  50  ruptures, permitting fluid communication between bore  18  and conduit  46 .  
         [0029]    Referring again to FIGS. 2 a ,  2   b ,  2   c ,  2   d , and  3  operation of first interventionless actuator  28   a  is described. When it is desired to utilize interventionless actuator  28   a  to open valve  16   a  of FIV  16  the pressure is increased in bore  18  overcoming the threshold of rupture disc  50 . Rupture disc  50  ruptures increasing the pressure within atmospheric pressure chamber  38  above that of second atmospheric pressure chamber  40  moving first power mandrel  36  downward. First power mandrel  36  contacts shoulder  32  of operating mandrel  30 , moving operating mandrel  30  down opening valve  16   a . The pressure in first and second pressure chambers  38  and  40  equalize and the chambers remain in constant fluid communication allowing valve  16   a  to be opened through mechanical intervention. A method and apparatus of achieving constant fluid communication between first atmospheric chamber  38  and second atmospheric chamber  40  is described in U.S. Pat. No. 6,516,886 to Patel, which is incorporated herein by reference.  
         [0030]    Referring to FIGS. 2 b ,  2   c  and  2   d  a second interventionless actuator  28   b  is shown. Interventionless actuator  28   b  is also a pressure operated actuator. Interventionless actuator  28   b  operates based on differential pressure between the inside pressure in bore  18  and an outside pressure in annular region  20 , that may be formation pressure. Interventionless actuator  28   b  includes a housing  52 , a second actuator power mandrel  54 , a port  56  formed through housing  50  in communication with the annulus  20 , a spring  58  urges power mandrel  54  downward, and a tension bar  60  holding power mandrel  54  in a set position. Tension bar  60  may be a shear ring or shear screws and our included in the broad definition of a tension bar for the purposes of this description for application as is known in the art.  
         [0031]    Interventionless actuator  28   a  is activated by creating a pressure differential between the inside pressure in bore  18  and the outside pressure in annular region  20 . One method of operation is to pressure up in bore  18  thus pushing second actuator power mandrel  54  upward until a predetermined pressure is achieved breaking tension bar  60 . The inside pressure may then be reduced and spring  58  urges power mandrel  54  downward into functional contact with shoulder  32  of operator mandrel  30  opening valve  16   a . The differential pressure between the outside and the inside of bore  18  created by bleeding off the inside pressure in bore  18  assists spring  58  to urge second power mandrel  54  down. Once valve  16   a  is cracked open the outside pressure and inside pressure will equalize. Spring  58  continues to urge power mandrel  54  downward. Valve  16   a  may be reclosed utilizing a physical intervention.  
         [0032]    Another method of operation includes bleeding inside pressure down in bore  18  creating a lower inside pressure than the outside pressure. Fluid passes through port  56  overcoming the inside pressure and forcing power mandrel  54  downward. When the downward force on power mandrel  54  overcomes the threshold of tension bar  60 , tension bar  60  parts allowing power mandrel  54  to move downward, contacting and urging power mandrel  30  downward opening valve  16   a.    
         [0033]    Embodiments of the invention may have one or more of the following advantages. By using multiple interventionless actuators pressure can be utilized to open the valve more than once while avoiding the need for a trip downhole to operate the valve. Multiple interventionless actuators further provide a redundancy whereby, if one interventionless actuator fails another independent interventionless actuator may be utilized. Even after successfully operating an interventionless actuator the valve can be subsequently opened and closed mechanically by a shifting tool.  
         [0034]    From the foregoing detailed description of specific embodiments of the invention, it should be apparent that a multiple interventionless actuated downhole valve that is novel has been disclosed. Although specific embodiments of the invention have been disclosed herein in some detail, this has been done solely for the purposes of describing various features and aspects of the invention, and is not intended to be limiting with respect to the scope of the invention. It is contemplated that various substitutions, alterations, and/or modifications, including but not limited to those implementation variations which may have been suggested herein, may be made to the disclosed embodiments without departing from the spirit and scope of the invention as defined by the appended claims which follow. For example, various materials of construction may be used, variations in the manner of activating each interventionless actuator, the number of interventionless actuators employed, and the type of interventionless actuators utilized. For example, it may desired to utilize an absolute pressure actuator for each of the interventionless actuators or utilized differing types of interventionless actuators.