Abstract:
A well completion has an expanded tubing portion and an unexpanded tubing portion. In another embodiment, an expandable tubing is provided and a gravel pack operation is performed. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]    The following is based on and claims the priority of provisional application No. 60/337,788 filed Nov. 13, 2001. 
     
    
     
       BACKGROUND OF THE INVENTION  
         [0002]    The present invention relates to the field of well completions. More specifically, the invention relates to a system and method for completing a well with expandable sections of tubing and sand screens.  
           [0003]    Expandable tubing and sand screens are becoming a viable technology for well completion. Further development of systems and methods improving and broadening the use of the expandable technology are desired.  
         SUMMARY  
         [0004]    In general, according to one embodiment, the present invention provides an expandable system that has expanded portions and unexpanded portions. In another embodiment, the present invention comprises gravel packing a well having an expandable tubing therein. The present invention comprises other embodiments as well.  
           [0005]    Other features and embodiments will become apparent from the following description, the drawings, and the claims. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    The manner in which these objectives and other desirable characteristics can be obtained is explained in the following description and attached drawings in which:  
         [0007]    [0007]FIG. 1 illustrates an embodiment of the present invention having expanded and unexpanded sections of tubing.  
         [0008]    [0008]FIG. 2 illustrates an embodiment of the present invention having an expandable completion with zonal isolation.  
         [0009]    [0009]FIG. 3 illustrates an embodiment of the present invention having expandable sand screens connected together by an unexpanded tubing section.  
         [0010]    [0010]FIG. 4 illustrates an embodiment of a crossover of the present invention.  
         [0011]    [0011]FIG. 5 illustrates an alternative embodiment of a crossover of the present invention.  
         [0012]    [0012]FIG. 6 illustrates an embodiment of the present invention in which the rat hole is gravel packed.  
         [0013]    [0013]FIG. 7 illustrates an embodiment of the gravel packing sub and service tool of the present invention.  
         [0014]    [0014]FIG. 8 illustrates an embodiment of the present invention in which the portion of the well between the expandable tubing sections is gravel packed.  
         [0015]    [0015]FIG. 9 illustrates an embodiment of the present invention in which a portion of the well is gravel packed. 
     
    
       [0016]    It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0017]    In the following description, numerous details are set forth to provide an understanding of the present invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.  
         [0018]    As used here, the terms “up” and “down”; “upper” and “lower”; “upwardly” and downwardly”; and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly described some embodiments of the invention. However, when applied to equipment and methods for use in wells that are deviated or horizontal, such terms may refer to a left to right, right to left, or other relationship as appropriate.  
         [0019]    Also, please note that the terms “seal” and “isolation” are used with the recognition that some leakage may occur and that such leakage may be acceptable. Thus, some embodiments of the present invention may allow for leakage without departing from the scope of the invention and systems that provide for such leakage fall within the scope of the present invention.  
         [0020]    [0020]FIG. 1 illustrates an embodiment of the present invention for the expandable completion system  10  in which a plurality of expandable tubing sections  12  are separated by an unexpanded tubing section  14 .  
         [0021]    As used herein an expandable tubing section  12  comprises a length of expandable tubing. The expandable tubing may be a solid expandable tubing, a slotted expandable tubing, an expandable sand screen, or any other type of expandable conduit. Examples of expandable tubing are the expandable slotted liner type disclosed in U.S. Pat. No. 5,366,012, issued Nov. 22, 1994 to Lohbeck, the folded tubing types of U.S. Pat. No. 3,489,220, issued Jan. 13, 1970 to Kinley, U.S. Pat. No. 5,337,823, issued Aug. 16, 1994 to Nobileau, U.S. Pat. No. 3,203,451, issued Aug. 31, 1965 to Vincent, the expandable sand screens disclosed in U.S. Pat. No. 5,901,789, issued May 11, 1999 to Donnelly et al., U.S. Pat. No. 6,263,966, issued Jul. 24, 2001 to Haut et al., PCT Application No. WO 01/20125 A1, published Mar. 22, 2001, U.S. Pat. No. 6,263,972, issued Jul. 24, 2001 to Richard et al., as well as the bi-stable cell type expandable tubing disclosed in U.S. patent application Ser. No. 09/973,442, filed Oct. 9, 2001. Each length of expandable tubing may be a single joint or multiple joints.  
         [0022]    The unexpanded tubing section  14  may comprise a section of tubing or conduit that is of a conventional configuration and not adapted for expansion. Alternatively, the unexpanded tubing section  14  may be a length of expandable tubing that is not expanded or only partially expanded so that its diameter is less than the diameter of the expandable tubing section  12 . Although generally shown in the illustrations as a relatively short section, the unexpanded tubing section  14  may be of any length and, in some embodiments, may be hundreds of feet in length.  
         [0023]    Referring to FIG. 1, a well  16  has a casing  18  extending to an open-hole portion  20 . At the upper end of the expandable completion system  10  is a hanger  22  connecting the expandable completion system  10  to a lower end of the casing  18 . A crossover section  24  connects the first expandable tubing section  12  to the hanger  22 . Note that any other known method of connecting an expandable tubing to a casing  18  may be used or the expandable completion system  10  may remain disconnected from the casing  18 . FIG. 1 is but one illustrative embodiment. A first expandable tubing section  12  (connected to the crossover section  24 ) is connected to a second expandable tubing section  12  by an unexpanded tubing section  14 .  
         [0024]    [0024]FIG. 2 illustrates an alternative embodiment of the present invention in which a plurality of expandable tubing sections  12  are separated by unexpanded tubing sections  14 . As in the embodiment of FIG. 1, the expandable completion system  10  is connected to the casing  18  of the well  16  by a hanger  22  (which may be a packer). A first expandable tubing section  12  connected to the hanger  22  by a crossover section  24  is also connected to a second expandable tubing section  12  by a first unexpanded tubing section  14 . The second expandable tubing section  12  is in turn connected to a third expandable tubing section  12  by a second unexpanded tubing section  14 . The expandable tubing sections  12  are aligned with separate perforated zones  26  and expanded. Each of the unexpanded tubing sections  14  has an external casing packer  28  (also referred to generally herein as a “seal”) thereon that provides zonal isolation between the expandable tubing sections  12  and associated zones. Note that the external casing packer may be replaced by other seals  28  such as an inflate packer, a formation packer, and or a special elastomer or resin. A special elastomer or resin refers to an elastomer or resin that undergoes a change when exposed to the wellbore environment or some other chemical to cause the device to seal. For example, the elastomer may absorb oil to increase in size or react with some injected chemical to form a seal with the formation. The elastomer or resin may react to heat, water, or any method of chemical intervention.  
         [0025]    In one embodiment the expandable tubing sections  12  are expandable sand screens and the expandable completion system  10  provides a sand face completion with zonal isolation. The expandable tubing sections and the unexpanded tubing sections may be referred to generally as an outer conduit or outer completion. In the embodiment of FIG. 2, the zonal isolation is completed by an inner completion  30  inserted into the expandable completion system  10 . The inner completion  30  comprises a production tubing  32  extending into the expandable completion system  10 . A first packer  34  positioned above the uppermost zone isolates the zone from the remainder of the well  16 . Additional packers  36  are aligned with and set in each of the unexpanded tubing sections  14 . With each of the zones isolated by the packers  34 ,  36 , the production of each zone may be separately controlled and monitored. It should be noted that the packers  36  maybe replaced by seal bores and seal assemblies or other devices capable of creating zonal isolation between the zones (all of which are also referred to generally herein as a “seal”). The unexpanded tubing section  14  may, in some embodiments, facilitate the isolation of the zones by providing a known inner diameter (as opposed to the generally variable diameter provided by an expanded tubing). In the embodiment shown, a valve  38  in the inner completion  30  provides for control of fluid flow from the associated formation into the production tubing  32 . The valve  38  may be controlled from the surface or a downhole controller by a control line  40 . Alternatively, the valve  38  may be of the type that requires intervention for actuation from opened to closed. In use, the expandable completion system  10  of FIG. 2 provides a sand face completion that allows for independently controlled production from each zone.  
         [0026]    Each isolated zone may further have monitoring and other devices therein as desired. For example, the inner completion  30  may have gauges, sensors, valves, sampling devices, a device used in intelligent or smart well completion, temperature sensors, pressure sensors, flow-control devices, flow rate measurement devices, oil/water/gas ratio measurement devices, scale detectors, actuators, locks, release mechanisms, equipment sensors (e.g., vibration sensors), pH meters, multiphase flow meters, acoustic sand detectors, solid detectors, sand detection sensors, water detection sensors, data recorders, viscosity sensors, density sensors, bubble point sensors, composition sensors, resistivity array devices and sensors, acoustic devices and sensors, other telemetry devices, near infrared sensors, gamma ray detectors, H 2 S detectors, CO 2  detectors, downhole memory units, downhole controllers, RF tags, locators, and other downhole devices in each isolated zone (referred to generally herein as “intelligent completion devices”).  
         [0027]    [0027]FIG. 3 shows an unexpanded embodiment of the present invention illustrating a crossover section  24  with an adjacent packer section  42 . The expandable completion system  10  shown in FIG. 3 also shows a pair of expandable tubing sections  12  connected by an unexpanded tubing section  14 . The expandable tubing sections  12  each comprise an expandable sand screen  44 . The expandable sand screen  44  has a filter layer  46  interposed between an outer expandable shroud  48  and an inner expandable tubing  50 . The expandable completion system  10  also has a pair of expandable seal elements  52  (also referred to generally herein as a “seal”) on either side of the unexpanded tubing section  14  that isolate the expandable tubing sections  12  from one another.  
         [0028]    [0028]FIGS. 4 and 5 illustrate components that may be used in the embodiment of FIG. 3. The crossover  54  of FIG. 4 has an expandable portion  56  and an unexpanded portion  58 . A seal element  52  is provided on the outer surface of the crossover  54 . The expanding end  60  of the crossover  54  is adapted for connection to an expandable tubing section  12 . Depending upon the type of expandable tubing used the connection may take many forms. Examples of the types of possible connections are those shown in U.S. Pat. No. 6,273,634 that issued Aug. 14, 2001 to Lohbeck, U.S. Pat. No. 5,984,568 which issued Nov. 16, 1999 to Lohbeck, and U.S. Pat. No. 5,924,745 that issued Jul. 20, 1999 to Campbell as well as U.S. Provisional Patent Application No. 60/263,934 which was filed Jan. 24, 2001.  
         [0029]    Likewise, the unexpanded end  62  is adapted for connection to an unexpanded tubing section  14  or another crossover (such as that shown in FIG. 5). The connection of the unexpanded end  62  is made using conventional connections (e.g., threaded connections).  
         [0030]    Whereas the crossover  54  of FIG. 4 shows a female crossover  54 , the crossover  64  of FIG. 5 is illustrative of an embodiment of a male crossover  64 . Like the female crossover  54 , the male crossover  64  has an expandable portion  56 , an unexpanded portion  58 , and a seal element  52  on the outer surface of the crossover  64 . As illustrated in the figures, the seal element  52  may be placed on the expandable portion  56  or the unexpanded portion  58 . In either case, the seal element  52  is adapted for expansion once properly positioned within the well  16 .  
         [0031]    [0031]FIG. 6 shows an alternative embodiment of the present invention in which an expandable tubing section  12 , which may be an expandable sand screen, is placed in the well  16  and expanded. A bottom end of the expandable tubing section  12  is connected to a crossover  66  connecting the expandable tubing section  12  to an unexpanded gravel packing sub  68 . In the embodiment shown, a bull plug  70  is connected to the bottom end of the gravel packing sub  68 .  
         [0032]    In use, the expandable tubing section  12  is expanded in the well  16 . A service string  72  (FIG. 7) is run into the well  16  through the expanded expandable tubing section  12  and into operative engagement with the gravel packing sub  68  and the rat hole  73  of the well  16  is gravel packed. The gravel may be delivered through the gravel packing sub  68  and the return may flow through the expandable tubing section  12  (e.g., expandable sand screen). In an alternative embodiment, the return flows through an unexpanded sand screen provided in the unexpanded tubing section  14 . Accordingly, one aspect of the present invention comprises the method of expanding an expandable sand screen in a well  16  and gravel packing the rat hole  73 , the area of the well  16  below the expandable sand screen.  
         [0033]    [0033]FIG. 7 shows one possible alternative embodiment of a gravel packing sub  68  and service string  72 . The gravel packing sub  68  comprises a housing  74  with a port  76  therethrough that communicates the interior passageway  78  of the gravel packing sub  68  with the exterior of the gravel packing sub  68 . In an alternative embodiment, shown in the figure, the port  76  may communicate with gravel pack shunt tubes  80  that extend axially along the well  16 . The shunt tubes  80  have spaced exit ports that distribute the gravel along the length of the well  16 . Within the housing  74  is a locating nipple  84  and a pair of sealing surface  86 , one on each side of the port  76 . The housing  74  further has end connections  88  that allow it to be connected to the completion.  
         [0034]    [0034]FIG. 7 also shows an exemplary service tool  90  in mating engagement with the housing  74 . The service string  72  is in fluid communication with a work string  92  that extends to the surface. A profile  94  in the service tool  90  ensures proper alignment between an exit port  96  in the service tool  90  and the port  76  of the housing  74 . Seals  98  on the service tool  90  on either side of the exit port  96  mate with the sealing surfaces  86  of the housing  74  to provide a sealed flowpath from the interior passageway  78  of the service tool  90 , through the exit ports  96  of the service tool  90  and the ports  76  of the housing  74  to the exterior of the housing  74  (which in an alternative embodiment of the invention communicates with shunt tubes  80  as previously described). Thus, gravel delivered through the workstring flows through the service tool  90  and gravel packing sub  68  and is delivered to the desired portion of the well  16 .  
         [0035]    [0035]FIG. 8 shows an alternative embodiment of the present invention in which the space  100  in the well  16  around an unexpanded tubing section  14  and between expandable tubing sections  12  is gravel packed. In one embodiment, the unexpanded tubing section  14  is positioned in a portion of the well  16  extending through a shale formation  102 . The expandable tubing sections  12  are provided, for example in sandstone formations  104  on either side of the shale formation  102 .  
         [0036]    As shown in the figure, two expandable tubing sections  12  (e.g., expandable sand screens) are separated by an unexpanded tubing section  14 . Note that the expandable tubing sections  12  may be referred to as expandable portions of a sand screen completion and the unexpanded tubing sections  14  may be referred to as intermediate unexpanded portions in that the unexpanded portions are intermediate expandable sand screen portions of the sand screen completion.  
         [0037]    The unexpanded tubing section  14  has a crossover  106  on each end connecting the unexpanded tubing section  14  to each of the expandable tubing section  12 . A gravel packing sub  68  is provided in the unexpanded tubing section  14 . Using a procedure similar to that described in connection with FIG. 7, the portion of the well  16  surrounding the unexpanded tubing section  14  and between the expandable tubing section  12  is gravel packed. A service string  72  is run into the well  16  into operative engagement with the gravel packing sub  68  and the gravel pack operation is performed. Accordingly, the present invention comprises the method of expanding a plurality of expandable sand screens in a well  16 , the expandable sand screens connected to one another by an unexpanded tubing section  14 , and gravel packing the portion of the well  16  around the unexpanded tubing portion and between the expandable sand screen.  
         [0038]    Note that the gravel pack may also flow to at least a portion of the area surrounding the expandable tubing section  12  if, for example, the expandable tubing section  12  is not fully expanded, if an annulus is formed around the expandable tubing section  12 , or if other flow paths exist through which the gravel pack may flow. Therefore, the present invention provides a method for gravel packing around an expandable tubing section  12  (e.g., an expandable sand screen).  
         [0039]    [0039]FIG. 9 illustrates another alternative embodiment in which the gravel packing sub  68  is provided above the expandable tubing section  12  to gravel pack the area  108  above the expandable tubing section  12 . The embodiment of FIG. 9, like those of FIGS.  6 - 8  may be used to provide a gravel pack around an expandable tubing section  12 , such as an expandable sand screen. A packer  110  at the upper end of the completion may be used as shown. The gravel packing sub  68  may have a closable sleeve therein.  
         [0040]    Although only a few exemplary embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the following claims. In the claims, means-plus-function clauses are intended to cover the structures described herein as performing the recited function and not only structural equivalents, but also equivalent structures. Thus, although a nail and a screw may not be structural equivalents in that a nail employs a cylindrical surface to secure wooden parts together, whereas a screw employs a helical surface, in the environment of fastening wooden parts, a nail and a screw may be equivalent structures. It is the express intention of the applicant not to invoke 35 U.S.C. §112, paragraph 6 for any limitations of any of the claims herein, except for those in which the claim expressly uses the words ‘means for’ together with an associated function.