Patent Abstract:
A method of expanding a tubular member by assembling an expansion system having an expansion cone and an expansion sleeve and coupling a tubular member to the expansion system so that the expansion sleeve is at least partially disposed within the tubular member. The expansion system and tubular member are then disposed in a wellbore and the expansion cone is translated relative to the expansion sleeve and tubular member so as to radially expand the tubular member into engagement with the wellbore and the expansion system is removed from the wellbore. The tubular member is expanded to an inside diameter equal to an expansion diameter of the expansion cone plus twice a thickness of the expansion sleeve.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61/988,740 filed May 5, 2014, the disclosure of which is hereby incorporated herein by reference for all purposes. 
    
    
     BACKGROUND 
     This disclosure relates generally to methods and apparatus for expanding wellbore tubular members, such as casing. More specifically, this disclosure relates to methods and apparatus for expanding a section of casing to an inside diameter that allows a second expandable tubular and expansion system to pass through the previously expanded section and then expanded to the same inside diameter. 
     In the oil and gas industry, expandable tubing is often used for casing, liners and the like. To create a casing, for example, a tubular member is installed in a wellbore and subsequently expanded by displacing an expansion cone through the tubular member. The expansion cone may be pushed or pulled using mechanical means, such as by a support tubular coupled thereto, or driven by hydraulic pressure. As the expansion cone is displaced axially within the tubular member, the expansion cone imparts radial force to the inner surface of the tubular member. In response to the radial force, the tubular member plastically deforms, thereby permanently increasing both its inner and outer diameters. In other words, the tubular member expands radially. Expandable tubulars may also be used to repair, seal, or remediate existing casing that has been perforated, parted, corroded, or otherwise damaged since installation. 
     In certain application, it may be desirable to install a series of expanded tubular sections having the same inside diameter. Many prior art expansion systems are sized so that the maximum diameter of the expansion system in a running configuration is too large to pass through a previously expanded tubular section and a smaller diameter system had to be used. 
     Thus, there is a continuing need in the art for methods and apparatus for expansion systems and methods that overcome these and other limitations of the prior art. 
     BRIEF SUMMARY OF THE DISCLOSURE 
     A method of expanding a tubular member by assembling an expansion system having an expansion cone and an expansion sleeve and coupling a tubular member to the expansion system so that the expansion sleeve is at least partially disposed within the tubular member. The expansion system and tubular member are then disposed in a wellbore and the expansion cone is translated relative to the expansion sleeve and tubular member so as to radially expand the tubular member into engagement with the wellbore and the expansion system is removed from the wellbore. The tubular member is expanded to an inside diameter equal to an expansion diameter of the expansion cone plus twice a thickness of the expansion sleeve. 
     An expansion system comprises a housing having a bore and an expansion piston disposed within the bore. An expansion cone is coupled to the expansion piston and has an expansion diameter. An expansion sleeve is coupled to the housing and has an inside diameter less than the expansion diameter of the expansion cone. A weakening feature is formed in the expansion sleeve. An expandable tubular disposed on a portion of the expansion sleeve. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more detailed description of the embodiments of the present disclosure, reference will now be made to the accompanying drawings, wherein: 
         FIG. 1  is a cross-sectional view of an expansion system in a running configuration. 
         FIG. 2  is an elevation view of an expansion system without an expandable tubular installed. 
         FIG. 3  is an elevation view of the expansion system of  FIG. 2  with an expandable tubular installed. 
         FIGS. 4-7  are partial sectional views of an expansion system installing an expandable tubular in a wellbore. 
         FIG. 8  is a partial sectional view of an expansion system being pulled from an installed expandable tubular. 
     
    
    
     DETAILED DESCRIPTION 
     It is to be understood that the following disclosure describes several exemplary embodiments for implementing different features, structures, or functions of the invention. Exemplary embodiments of components, arrangements, and configurations are described below to simplify the present disclosure; however, these exemplary embodiments are provided merely as examples and are not intended to limit the scope of the invention. Additionally, the present disclosure may repeat reference numerals and/or letters in the various exemplary embodiments and across the Figures provided herein. This repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various exemplary embodiments and/or configurations discussed in the various figures. Moreover, the formation of a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed interposing the first and second features, such that the first and second features may not be in direct contact. Finally, the exemplary embodiments presented below may be combined in any combination of ways, i.e., any element from one exemplary embodiment may be used in any other exemplary embodiment, without departing from the scope of the disclosure. 
     Additionally, certain terms are used throughout the following description and claims to refer to particular components. As one skilled in the art will appreciate, various entities may refer to the same component by different names, and as such, the naming convention for the elements described herein is not intended to limit the scope of the invention, unless otherwise specifically defined herein. Further, the naming convention used herein is not intended to distinguish between components that differ in name but not function. Additionally, in the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to.” All numerical values in this disclosure may be exact or approximate values unless otherwise specifically stated. Accordingly, various embodiments of the disclosure may deviate from the numbers, values, and ranges disclosed herein without departing from the intended scope. Furthermore, as it is used in the claims or specification, the term “or” is intended to encompass both exclusive and inclusive cases, i.e., “A or B” is intended to be synonymous with “at least one of A and B,” unless otherwise expressly specified herein. 
     Referring initially to  FIG. 1 , an expansion system  10  includes a housing  12 , an expansion piston  14 , a mandrel  16 , and an expansion sleeve  18 . Configured in a running position, as shown in  FIGS. 1 and 3 , an expandable tubular  20  is disposed over a portion of the expansion sleeve  18 . The exterior of the expandable tubular  20  may be fitted with sealing members  22  that form a seal between the expandable tubular  20  and the surrounding wellbore when the expandable tubular  20  is expanded. The expansion system  10  has a gauge diameter  24  that is defined by the largest outside diameter of system which may be maximum outside diameter of (i) the housing  12 , (ii) the sealing members  22 , (iii) the expandable tubular  20  if not equipped with sealing members  22 , or (iv) the expansion sleeve  18 . 
     The housing  12  includes a housing wall  26  having an upper end  28  and a lower end  30 . The upper end  28  is configured to be coupled to a drill string (not shown) or to some other support member, such as tubing or wireline, as well as provide fluid communication with a supply of hydraulic fluid through housing inlet  32 . The housing wall  26  includes fluid ports  34  that provide fluid communication across the housing wall  26 . 
     The expansion piston  14  is disposed within the housing  12  and includes an elongate body  36  having a bore  38 , a piston end  40 , and an expansion cone  42 . The piston end  40  may include a ball seat  41  and one or more sealing members  44  that sealingly engage the housing wall  26 . The expansion cone  42  includes a profiled surface  46  having an initial diameter  48  and an expansion diameter  50 . The mandrel  16  is partially disposed within the bore  38  of the housing  12 . The mandrel  16  includes a flowbore  52 , outlet port  54 , retainer flange  56 , and an upper shoulder  58 . 
     The expansion sleeve  18  is a tubular member having a wall thickness  60 . The expansion sleeve  18  is sized and configured to have a minimum resistance to radial expansion, or minimum hoop strength. As the wall thickness  60  of the expansion sleeve  18  is determined by the geometrical limitations of the expansion system  10 , the hoop strength of the expansion sleeve  18  can be reduced by forming one or more weakening features  62  in the wall of the expansion sleeve. In the embodiment illustrated in  FIGS. 2 and 3 , the weakening features  62  include a plurality of longitudinal slots  64  that extend along a substantial length of the expansion sleeve  18 . In other embodiments, the weakening features may include perforations, grooves, holes, cut outs, or other slot configurations. 
     The expansion sleeve  18  has an upper end  66  that is coupled to the lower end  30  of the housing  12 . The upper end  66  of the expansion sleeve  18  is formed with an inside diameter that accommodates the expansion diameter  50  of the expansion cone  42 . The upper end  66  of the expansion sleeve  18  has an outside diameter that may be equal to or slightly smaller than the gauge diameter  24  of the expansion system  10 . The expansion sleeve  18  has a weakened portion that includes the weakening features  62  and fits inside the expandable tubular  20  and has an inside diameter sized to engage the initial diameter  48  of the expansion cone  42 . 
     As will be described in detail to follow, as the expansion system  10  operates, the expandable tubular member  20  is expanded to an inside diameter, or drift diameter, that is substantially equal to the expansion diameter  50  of the expansion cone  42  plus two times the wall thickness  60  of the expansion sleeve  18 . The expansion diameter  50  and the wall thickness  60  may be selected so that the expanded inside diameter, or drift diameter, of the expandable tubular member  20  is greater than the gauge diameter  24  of the expansion system  10 . With this configuration, an expansion system  10  can pass through, and be expanded below, an expandable tubular member  20  that has previously been installed in a wellbore. 
     Referring now to  FIG. 4 , once the expansion system  10  is assembled, as shown in  FIG. 3 , it can be run into a wellbore  80  on drill pipe (not shown). In certain installations, the wellbore  80  may already include a casing section  82  that the expansion system  10  can pass through. Once the expansion system  10  is located at a desired location within wellbore  80 , a ball  84  is dropped from the surface and sealingly engages the ball seat  41  of the expansion piston  14 . The engagement of the ball  84  and ball seat  41  prevents fluid flow through the bore  38 . 
     Once the ball  84  is engaged with the ball seat  41 , continued supply of pressurized fluid to the expansion system  10  will create a pressure differential across piston end  40  of the expansion piston  14 . This pressure differential generates an axial force on the expansion piston  14 , which will move the expansion cone  42  axially through the expansion sleeve  18  and expandable tubular member  20 . 
     As shown in  FIG. 5 , as the expansion cone  42  passes axially through the expansion sleeve  18  and the expandable tubular member  20 , the expandable tubular member  20  is expanded to an inside diameter  86 . The inside diameter  86  is equal to the expansion diameter  50  of the expansion cone  42  plus twice the thickness  60  of the expansion sleeve  18 . As the expandable tubular member  20  is expanded, the sealing members  22  are compressed between the expandable tubular member  20  and the surrounding wellbore  80 . 
     The expansion piston  14  will continue to move through the housing  12  until the expansion cone  42  passes fully through the expansion sleeve  18 . At this point, fluid ports  34  will allow fluid to exit the bore  38  and equalize the differential pressure acting on the expansion piston  14 . Once the expansion piston  14  has reached this position, the expansion cone  42  has passed fully through the expansion sleeve  18  and the expandable tubular member  20  is coupled to the surrounding wellbore  80  by the compression of the sealing members  22  between the tubular member  20  and the surrounding wellbore  80 . 
     Referring now to  FIGS. 7 and 9 , once the tubular member  20  has been fully expanded, the expansion system  10  can then be pulled upward. As the expansion system  10  is pulled upward, the expansion sleeve  18  will deflect inward as necessary, thus allowing the expansion system  10  to be removed from the tubular member  20  and pass through a previously expanded casing section  82  if necessary. Another expansion system  10  with an unexpanded expansion sleeve  18  and tubular member  20  can then be run into the wellbore  80  and installed at a lower location in the wellbore. 
     Although the figures show expansion system  10  being operated as a top-down system, in certain embodiments the system can be operated as a bottom-up system. In these embodiments, the expansion cone will initially be positioned at the lower end of the expansion sleeve and expandable tubular member. Similar to the illustrated embodiment, internal pressure will push the expansion cone upward through the expansion sleeve and expandable tubular member and then the cone and sleeve can be retrieved from the wellbore. 
     While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and description. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the disclosure to the particular form disclosed, but on the contrary, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present disclosure.

Technology Classification (CPC): 4