Abstract:
Disclosed herein is a downhole sealing device. The device includes a swellable member, and a passageway having a perimetrically continuous wall. The swellable member is configured to cause sealing between a downhole structure and a plurality of tubulars when in a swelled condition, the plurality of tubulars are routed through a plurality of voids extending longitudinally through the swellable member, each of the plurality of voids has perimetrically continuous walls surrounding each of the plurality of tubulars.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a divisional application of U.S. patent application Ser. No. 12/402,667, filed Mar. 12, 2009, the entire contents of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    It is common in the hydrocarbon recovery industry to have a need to plug an annular space defined by a tubular and a downhole wellbore structure, such as, a liner, casing or open hole, for example, within which the tubular is positioned. One sealing method includes positioning a swellable member perimetrically about the tubular prior to positioning the tubular within the downhole structure. The swellable member swells in response to exposure to downhole fluids such as oil or water for example. The swelling of the swellable member causes the swellable member to fill the annular space and to sealingly engage with walls of both the tubular and the downhole structure. 
         [0003]    Establishing and maintaining a well secured communication from one side of the swellable seal to the other can be useful in well operations. Unsecured communication lines can have a far greater operational cost, which may result in having to exit from the borehole in order to make further securing repairs. Excessive vibration caused by one tool traveling down the borehole may adversely affect the performance of other tools obtaining valuable downhole data. That vibration creation along with unsecure communication lines may only amplify false results. Such amplification from those unsecure lines would be in comparison to a tuning fork when strike. In most gamma ray equipped downhole tools, the smooth transition of multiple or single photo multiplier tubes are important in order to provide the necessary pulse of light via the tubes. Any sharp bends or vibration may only destroy this very important light communication. Another example is on a telemetry downhole tool, mud pulses are registered by these types of tools via an electrical sensor. Any additional impacts from unsecured communication lines will only amplify noises or even provide false readings that are important to this data gathering. Systems and methods, therefore, that permit sealing and maintaining a solid lock down in an annular space while maintaining a communication passageway across the seal are desirable in the art. 
       BRIEF DESCRIPTION 
       [0004]    Disclosed herein is a downhole sealing device. The device includes, a swellable member, and a passageway having a perimetrically continuous wall. The swellable member is configured to cause sealing between a downhole structure and a plurality of tubulars when in a swelled condition, the plurality of tubulars are routed through a plurality of voids extending longitudinally through the swellable member, each of the plurality of voids has perimetrically continuous walls surrounding each of the plurality of tubulars. 
         [0005]    Further disclosed herein is a downhole swellable sealing system with passageway. The system includes, at least one substantially nonswellable member, and a swellable member in operable communication with the at least one substantially nonswellable member. The swellable member is configured to cause sealing between a downhole structure and a plurality of tubulars when in a swelled condition, the plurality of tubulars are routed through a plurality of voids that extend longitudinally through at least one of the swellable member and the at least one substantially nonswellable member, and each of the plurality of voids has perimetrically continuous walls surrounding each of the plurality of tubulars. 
         [0006]    Further disclosed herein is a method of making a downhole swellable seal with a passageway therethrough. The method includes, perimetrically surrounding a first tubular with a first substantially nonswellable material, perimetrically surrounding at least one second tubular with a second substantially nonswellable material, positioning the at least one second tubular adjacent the first tubular, perimetrically surrounding the first tubular and the at least one second tubular with a swellable material, curing the first substantially nonswellable material, curing the second substantially nonswellable material, and curing the swellable material. 
     
    
     
       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 perspective view of a downhole swellable sealing system with passageway as disclosed herein; 
           [0009]      FIG. 2  depicts a magnified side view of a portion of the downhole swellable sealing system of  FIG. 1 ; 
           [0010]      FIG. 3  depicts a cross sectional side view of an embodiment of the swellable sealing system of  FIG. 2 ; 
           [0011]      FIG. 4  depicts a perspective view of the swellable sealing system of  FIG. 1  during a forming operation of perimetrically continuous voids; and 
           [0012]      FIG. 5  depicts a cross sectional side view of an alternate embodiment of the swellable sealing system of  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    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. 
         [0014]    Referring to  FIGS. 1 and 2 , an embodiment of the swellable sealing system  10  with passageway disclosed herein is illustrated. The swellable sealing system  10  includes, a substantially nonswellable member  18 , a swellable member  22 , and at least one void  28  with a perimetrically continuous wall extending longitudinally through at least one of the substantially nonswellable member  18  and the swellable member  22 . The substantially nonswellable member  18  perimetrically surrounds a first tubular  14  and at least one second tubular  26  is positioned within the void  28 . The second tubular  26  is preferably constructed of a rigid material such as stainless steel, for example, and has an inner cavity defining a passageway  30  (as best illustrated in the cross sectioned views in  FIGS. 3 and 5 ). The swellable sealing system  10  is configured to seal an annular space  34  defined in this embodiment by the first tubular  14  and a downhole structure  38  that the system  10  is positioned substantially concentric with, such as, a liner, casing or open hole, for example, while providing the passageway  30  therethrough, via the second tubular  26 . It should be noted that alternate embodiments could be configured to seal an annular space that is defined radially inwardly of the first tubular  14  and radially outwardly of a downhole structure positionable within at least a portion of the first tubular. The passageway fluidically connects a portion of the annular space  34 A beyond one longitudinal end of the nonswellable member  18  to a portion of the annular space  34 B beyond an opposite longitudinal end of the nonswellable member  18 . The passageway  30  can be used as a control line directly with hydraulic fluid being ported therethrough, for example, or as a conduit for running a separate control line (not shown), such as, electric line or fiber optic cable, for example. 
         [0015]    The swellable member  22  may be constructed of any swellable material known in the industry such as polymers that swell when exposed to conditions commonly encountered downhole such as oil or water, for example. In contrast, the nonswellable member  18  may be constructed of known materials that tend to be substantially nonswellable when exposed to the same downhole conditions mentioned above. 
         [0016]    Referring to  FIG. 3 , the perimetrically continuous void  28  extends longitudinally through the nonswellable member  18 . Since walls  42  of the void  28  are continuous they have no perimetrical interruptions, such as a longitudinal slit through the nonswellable member  18 , for example, and are therefore easily sealed to an outer radial surface  46  of the second tubular  26 . Optionally, a mechanical device  48  can be sealably attached to both the second tubular  26  and the nonswellable member  18  at both ends where the second tubular  26  exits from the nonswellable member  18  thereby preventing any movement between the second tubular  26  and the nonswellable member  18 . Additionally, by making the mechanical device  48  metal the seal between the second tubular  26  and the mechanical device can be a metal-to-metal seal. Embodiments of processes to make the swellable sealing system  10  and particularly the perimetrically continuous void  28  will be described below. 
         [0017]    Referring to  FIG. 4 , an embodiment of a process to make the swellable sealing system  10  is illustrated generally at  50 . A first nonswellable material  54  is wrapped perimetrically around the first tubular  14 . At least one second tubular  26  is positioned substantially parallel to the first tubular  14  and a second nonswellable material  58  is wrapped around both the first tubular  14  and the second tubular  26 . Wrapping additional layers of a third nonswellable material  60  around both the first tubular  14  and the second tubular  26  forms a first dam  62 A and a second dam  62 B. Nylon (not shown) or other material capable of holding the nonswellable materials  54 ,  58  and  60  in position while being heated to curing temperatures is wrapped around all of the nonswellable materials  54 ,  58  and  60 . The full assembly is heated to cure the nonswellable materials  54 ,  58  and  60 . After curing, the nylon is removed and a swellable material  66  is wrapped perimetrically around the nonswellable materials  54 ,  58  between the dams  62 A and  62 B. Nylon or other material is then wrapped around the swellable material  66  and the full assembly is again heated, this time to cure the swellable material  66 . The nylon is removed after curing. 
         [0018]    Optionally, the step of wrapping the second tubular  26  with the nonswellable material  58 , could be replaced with wrapping a rod  70  (or other reusable manufacturing tubular). This may be desirable to avoid oxidation and possible contamination of the passageway  30  of the second tubular  26  that could occur during manufacture or during the high temperature curing processes. If the rod  70  were used it would be employed to form the perimetrically uninterrupted longitudinal void  28  in the nonswellable material  58 . Doing so, however, would require withdrawal of the rod  70  upon completion of the last curing cycle. Application of a release agent, such as, mold release, for example, to the rod  70  prior to it being wrapped in the nonswellable material  58  could facilitate its withdrawal upon completion of the curing process. A step of inserting the second tubular  26  into the void  28  could be done in conjunction with the withdrawal of the rod  70 , by attaching and end of the second tubular  26  to an end of the rod  70 . The action of withdrawing the rod  70  would then also insert the second tubular  26  into the void  28 . 
         [0019]    Referring to  FIG. 5 , optionally, the nonswellable materials  54 ,  58 ,  60  could be wrapped only at the dams  62 A and  62 B. In such case, the swellable material  66  would be wrapped directly over the first tubular  14  and the second tubular  26  (or rods  70 ) between the dams  62 A and  62 B as desired by a well operator. 
         [0020]    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. 
         [0021]    While one or more embodiments have been shown and described, modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustrations and not limitation.