CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Application No. 13/314646, filed on December 8, 2011, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] Tubular systems, such as those used in the completion and carbon dioxide sequestration industries often employ anchors to positionally fix one tubular to another tubular. Although existing anchoring systems serve the function for which they are intended, the industry is always receptive to new systems and methods for anchoring tubulars.

BRIEF DESCRIPTION

[0003] Disclosed herein is a treatment plug. The treatment plug includes, a metal tubular expandable into sealing and anchoring engagement with a surrounding structure, the metal tubular having a shoulder at an inner radial surface thereof, and a composite plug sealable with the metal tubular and anchorable to the shoulder.

[0004] Further disclosed herein is a method of anchoring a treatment plug and then removing a portion thereof. The method includes, positioning the treatment plug having a metal tubular with a shoulder engaged with a composite plug within a structure, swaging the metal tubular into sealing and anchoring engagement with the structure, plugging the composite plug, performing a treating operation, and drilling out the composite plug.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:

[0006] FIG. 1 depicts a cross sectional view of a treatment plug disclosed herein within a borehole in an earth formation; and

[0007] FIG. 2 depicts a cross sectional view of a portion of the treatment plug of FIG.

1. DETAILED DESCRIPTION

[0008] 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.

[0009] Referring to Figure 1, an embodiment of a treatment plug disclosed herein is illustrated at 10. The treatment plug 10 includes, a metal tubular 14 with a shoulder 18 at an inner radial surface 22 thereof, and a composite plug 26 sealable with the metal tubular 14 and anchorable to the shoulder 18. The metal tubular is sealingly and anchorably attachable to a structure 30, shown herein as a borehole in an earth formation 34 in response to the metal tubular 14 being radially expanded. The treatment plug 10 can include a seal 38, such as polymeric sleeve, for example to aid in sealing the metal tubular 14 to the structure 30.

Additionally, one or more slips 42 can be positioned radially outwardly of the metal tubular 14 to facilitate anchoring engagement of the treatment plug 10 to the structure 30.

[0010] The composite plug 26 of the embodiment illustrated herein has a composite lower ring 46 and composite bottom 66 that abut opposing sides of the shoulder 18 to anchor the composite plug 26 to the metal tubular 14. A seal 50, made of a polymer such as rubber, for example, is compressible between the composite lower ring 46 and a composite upper ring 54. Compression of the seal 50 causes radial expansion thereof and subsequent sealing engagement to both the inner radial surface 22 of the metal tubular 14 and a surface 58 of a composite mandrel 62. The mandrel 62 is attached to the composite bottom 66 and a sleeve 64 while the lower ring 46, the seal 50, and the upper ring 54 are able to move relative to the mandrel 62. The attachment of the mandrel 62 to these components is sufficiently strong to prevent detachment while pulling on the mandrel 62 relative to the metal tubular 14 during swaging of the metal tubular 14 and during pushing on the mandrel 62 relative to the metal tubular 14 during treating operations such as fracing of the earth formation 34, for example.

[0011] A setting tool 74 is operationally attachable to the composite plug 26, for example, through releasable engagement of a collet (not shown) on a sleeve 78 of the setting tool 74 to the composite mandrel 62. This attachment allows a swage 82 of the setting tool 74 to move relative to the sleeve 78 and the metal tubular 14 connected thereto. Movement of the swage 82 causes radial expansion of the metal tubular 14 thereby radially expanding the seal 38 into sealing engagement with the structure 30 and radially expanding the slips 42 into anchoring engagement with the structure 30. Subsequent the radial expansion of the metal tubular 14 the setting tool 74 is retrievable, perhaps to surface, after detaching from the composite plug 26. [0012] Referring additionally to Figure 2, once the setting tool 74 has been removed, the treatment plug 10 is set to receive a plug 86, illustrated herein as a ball, seatable against a seat 90 on the composite mandrel 62. The plug 86 can also be made of composite material to facilitate later removal by drilling or milling with the rest of the components that make up the composite plug 26. The composite plug 26 is attached to the metal tubular 14 with sufficient strength, and the metal tubular 14 is anchored to the structure 30 with sufficient strength to prevent relative movement between these parts during pressuring up against the composite plug 26 while plugged with the plug 86 during a treating operation such as a fracing operation or a pressure actuating event, for example.

[0013] After any desired treatments are completed the composite plug 26 and the plug 86 are removable by machining them via a drilling or milling operation. The treatment plug 10 is configured such that once the composite plug 26 portion has been removed a relatively large through bore 94 of the metal tubular 14, is the only restriction that remains within the structure 30. The through bore 94 can be configured so that a radial dimension 98 thereof is greater than 80 percent of a greatest radial dimension 102 of the treatment plug 10 after it has been set. This large radial dimension 98 allows flow through the through bore 94 for production of hydrocarbons, for example, with little restriction. A plurality of the treatment plugs 10 can be employed within a single one of the structures 30 and all of the treatment plugs 10 can subsequently be drilled out thereby leaving little restriction to flow

therethrough.

[0014] 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.