Abstract:
A tubular valving system includes, a tubular having a bore therethrough with at least one port defining fluidic communication between the bore and an outside of the tubular, and a valve stem disposed within the bore of the tubular that is longitudinally movable with respect to the tubular, the valve stem has an outer surface slidably engagable with the bore, the outer surface has features that provide variably choked fluidic communication between the bore and the at least one port, and an amount of choke varies depending upon a relative position of the valve stem with respect to the bore

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application contains subject matter related to the subject matter of co-pending applications, which are assigned to the same assignee as this application, Baker Hughes Incorporated of Houston, Tex. The below listed applications are hereby incorporated by reference in their entirety: 
         [0002]    U.S. Patent Application Attorney Docket No. 274-49265-US, entitled MODULAR VALVE BODY AND METHOD OF MAKING; and 
         [0003]    U.S. Patent Application Attorney Docket No. 274-49267-US, entitled TUBULAR VALVE SYSTEM AND METHOD. 
     
    
     BACKGROUND 
       [0004]    Tubular valves that control occlusion of ports that fluidically connect a borehole of a tubular with an outside of the tubular are commonly used in several industries including the downhole completion industry. Such valves are deployed in boreholes to control fluid flow in both directions, inside to outside of the tubular as well as outside to inside of the tubular, through the ports. Needle valves with tapered seats and tapered plungers are commonly employed in applications where variable choking of the flow is desirable. The fit of the tapered plunger into the tapered seat, however, creates very tight clearances that are subject to jamming, preventing closure of the valve, by relatively small sized particles. In environments wherein contamination is prevalent, use of such valves can result in the inability to fully close the valve possibly necessitating removal, repair, cleaning or replacement of the valve. Costs associated with removal of the valve from the wellbore to repair or replace the valve, in addition to the cost of lost production while the well is not producing, are a few of the concerns associated with use of these valves. Systems and methods that overcome the foregoing concerns would be well received in the art. 
       BRIEF DESCRIPTION 
       [0005]    Disclosed herein is a tubular valving system. The system includes, a tubular having a bore therethrough with at least one port defining fluidic communication between the bore and an outside of the tubular, and a valve stem disposed within the bore of the tubular that is longitudinally movable with respect to the tubular, the valve stem has an outer surface slidably engagable with the bore, the outer surface has features that provide variably choked fluidic communication between the bore and the at least one port, and an amount of choke varies depending upon a relative position of the valve stem with respect to the bore. 
         [0006]    Further disclosed herein is a method of choking a tubular valve. The method includes, slidably engaging a valve stem within a bore of a tubular between an open end of the tubular and at least one port fluidically connecting the bore to an outside of the tubular, and varying at least one of a flow path area or a flow path length between the bore and the at least one port by moving the valve stem relative to the tubular. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike: 
           [0008]      FIG. 1  depicts a cross sectional view of the tubular valving system disclosed herein in a fully open position; 
           [0009]      FIG. 2  depicts a cross sectional view of the tubular valving system of  FIG. 1  in a fully closed position; 
           [0010]      FIG. 3  depicts a cross sectional view of the tubular valving system of  FIG. 1  in a partially choked position; 
           [0011]      FIG. 4  depicts a perspective view of a valve stem disclosed herein; 
           [0012]      FIG. 5  depicts a perspective view of an alternate valve stem disclosed herein; 
           [0013]      FIG. 6  depicts a perspective view of an alternate valve stem disclosed herein; 
           [0014]      FIG. 7  depicts a perspective view of an alternate valve stem disclosed herein; and 
           [0015]      FIG. 8  depicts a perspective view of yet another an alternate valve stem disclosed herein. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures. 
         [0017]    Referring to  FIGS. 1-3 , a tubular valving system is illustrated generally at  10 . The valving system  10  includes, a tubular  14 , having a bore  18  therethrough and a port  22  that fluidically connects the bore  18  to an outside  26  of the tubular  14 , and a valve stem  30  slidably engaged with the bore  18 . The valving system  10  is configured such that movement of the valve stem  30  in relation to the tubular  14  controls variable choking of flow between the bore  18  and the port  22 . 
         [0018]    The bore  18  has a step  32  defining a non-tapered smaller dimension  34  and a larger dimension  38 , depicted in this embodiment as diameters, with a radial surface  42  located at the step  32 . The port  22  fluidically connects the larger dimension  38  to the outside  26  of the tubular  14 . Although the port  22  illustrated includes only a single opening, an embodiment having a port  22  with multiple openings is contemplated. The valve stem  30  includes a shoulder  46  that steps to a greater dimensioned portion  50  and a distal portion  54  with a nose cone  58  thereon. The valve stem  30  is longitudinally movable relative to the tubular  14  to a first position (illustrated in  FIG. 2 ), defined by the shoulder  46  sealingly contacting the radial surface  42  thereby fully occluding or closing fluid communication between the bore  18  and the port  22 , and a second position (illustrated in  FIG. 1 ) defined by retraction of the valve stem  30  until the distal portion  54  is beyond the port  22  thereby fully opening fluid communication between the bore  18  and the port  22 . 
         [0019]    Referring to  FIG. 3 , the valve stem  30  is illustrated in a choke position between the fully open and the fully closed positions. In the choke position the valve stem  30  chokes fluid communication between the bore  18  and the port  22 . This choking is due to a reduction in flow area defined between the valve stem  30  and the non-tapered smaller dimension  34  of the bore  18 . The slidably engagable fit of a non-tapered outer dimension  60  of the distal portion  54  of the valve stem  30  within the non-tapered smaller dimension  34  of the bore  18  substantially forms a seal therebetween. A plurality of grooves  62  formed in the non-tapered outer dimension  66  of the valve stem  30  defines the flow area. The larger dimension portion  38  provides fluid communication between each of the grooves  62  open thereto and the port  22 . 
         [0020]    Referring to  FIG. 4 , the valve stem  30  is illustrated in a magnified perspective view. The grooves  62  include circumferential grooves  62 A that are fluidically connected to longitudinal grooves  62 B. At least one of the longitudinal grooves  62 B extends beyond the non-tapered outer dimension  60  of the distal portion  54  and into the nose cone  58  thereby establishing a flow area between the non-tapered smaller dimension  34  and the non-tapered outer dimension  60  when the non-tapered dimension outer dimension  60  is slidably engaged with the non-tapered smaller dimension  34 . This flow area is maintained through the grooves  62 A and  62 B to the larger dimension  38  and into the port  22 . The further the non-tapered outer dimension  60  is engaged with the non-tapered smaller dimension  34  the longer the flow path is defined by the grooves  62 A and  62 B and the greater the resistance to fluid flow therethrough and the greater the choking of the flow. The dimensions and number of the grooves  62 A and  62 B can be selected to establish desired choke characteristics. For example, by increasing the number of circumferential grooves  62 B in comparison to the number of longitudinal grooves  62 A an operator can increase a length through which fluid must flow and increase the number of sharp turns the fluid must navigate during traverse from between the bore  18  and the port  22 . 
         [0021]    Referring to  FIG. 5 , an alternate embodiment of a valve stem  122  is illustrated with like elements from earlier figures numbered alike. The valve stem  122  includes longitudinal grooves  62 A that extend from the nose cone  58  to near the shoulder  46 . This embodiment presents a less tortuous flow path between the bore  18  and the port  22 , than the valve stem  122 . 
         [0022]    Referring to  FIG. 6 , an alternate embodiment of a valve stem  222  is illustrated with like elements from earlier figures numbered alike. The valve stem  222  has a hollow distal portion  254  that has an inner bore  256  that extends all the way to a nose cone  258 . A plurality of slots  262  fluidically connects the non-tapered outer dimension  60  to the inner bore  256 . Since the slots  262  do not extend beyond the non-tapered outer dimension  60  area they do not fluidically connect directly with the non-tapered smaller dimension  34  of the bore  18  but only fluidically connect thereto through the inner bore  256 . As such, all flow between the bore  18  and the port  22  needs to pass through the inner bore  256  and through at least one of the slots  262 . 
         [0023]    Referring to  FIG. 7 , an alternate embodiment of a valve stem  322  is illustrated with like elements from earlier figures numbered alike. The valve stem  322  has a hollow distal portion  354  that has a bore  356  that extends all the way to a nose cone  358 . A plurality of ports  362  fluidically connects the non-tapered outer dimension  60  to the bore  356 . As such, all flow between the bore  18  and the port  22  needs to pass through the bore  356  and through at least one of the ports  362 . 
         [0024]    Referring to  FIG. 8 , an alternate embodiment of a valve stem  422  is illustrated with like elements from earlier figures numbered alike. The valve stem  422  is similar to the valve stem  322  with the primary difference being that in the valve stem  422  a cross sectional area of a plurality of ports  462  varies in size. This size variation allows an operator greater control over the relationship between an amount of choke provided by the valving system  10  in relation to a positioning of the valve stem  422  within the non-tapered smaller dimension  34  of the bore  18 . For example, by making the ports  462  nearer to the shoulder  46  smaller than the ports  462  further from the shoulder  46  (as is illustrated in this embodiment) for each additional incremental movement of the valve stem  422  in a more choking direction the amount of choking increases a greater amount than when the valve stem  422  previously moved the same incremental movement. 
         [0025]    While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.