Patent Application
20130299197
None
This disclosure relates generally to methods and apparatus for expanding a tubular member in a wellbore. More specifically, this disclosure relates to expanding a tubular member using an adjustable expansion cone.
Wellbore tubular members, such as casings or liners, can be expanded in the wellbore using a variety of known processes. These processes often utilize expansion cones that are shaped to radially expand the tubular as the cone moved axially through the tubular. Many conventional expansion cones have a fixed outer diameter that is larger than the outer diameter of tubular member before expansion. The size of the fixed diameter expansion cone necessitates that, before expansion begins, the cone is contained within an enlarged section of the tubular, known as a launcher, or disposed outside of the tubular being expanded.
The launcher, or the expansion cone itself, is thus the component of the tool string having the largest outer diameter and is therefore a major factor in determining the operating envelope of the system. For example, if an expandable tubular is needed at a location in the wellbore below a restriction, the size of the launcher or cone will limit the systems that can be used. Fixed diameter cones are also susceptible to getting stuck in the unexpanded tubular should the expansion process fail or an unexpected restriction be encountered.
Adjustable expansion cones have been used to overcome some of the limitations of fixed diameter cones by providing a mechanism for varying the outer diameter of the cone. Adjustable expansion cones generally include a plurality of segments that are “assembled” downhole into a cone capable of expanding a tubular member. Adjustable cones are available in a variety of styles and configurations but, like conventional fixed diameter cones, suffer from certain performance limitations.
One issue that has limited the use of adjustable cones is the force needed to assemble the cone. If the cone is assembled in the tubular, the force needed to assemble the cone while simultaneously expanding the tubular can be significant. Previous systems have addressed this issue by including specialized force generators to provide the needed force and/or assembling the cone within a thin-walled section of the tubular in order to reduce the forces required. Certain systems include mechanisms to extend the adjustable cone out of the lower end of the tubular so as to assemble the cone in the open wellbore and avoid the problems caused by assembling the cone and expanding the tubular simultaneously. Each of these solutions adds complexity and costs to the expansion system.
Thus, there is a continuing need in the art for methods and apparatus for adjustable expansion cones that overcome these and other limitations of the prior art.
One embodiment of the disclosure provides an expansion system comprising a mandrel slidably coupled to plurality of primary cone segments that are interleaved with a plurality of secondary cone segments. The expansion system has a the first position wherein the primary cone segments and secondary cone segments are in a retracted position, a second position wherein the primary cone segments are in an expanded position and the secondary cone segments are in a retracted position, and a third position wherein the primary cone segments and the secondary cone segments are in an expanded position. When the expansion assembly is disposed within a tubular member and in the second position, the primary cone segments expand the tubular member into a tri-lobe cross-sectional shape.
Another embodiment of the disclosure provides a method for expanding a tubular by assembling an expansion system that includes a mandrel that is slidably coupled to plurality of primary cone segments that are interleaved with a plurality of secondary cone segments. The expansion system is assembled in a first position and disposed into a tubular member having an unexpanded inner diameter. The expansion system is transitioned to a second position where the primary cone segments radially expand the tubular member into a tri-lobe cross-sectional shape. The expansion system is then transitioned to a third position where the primary and secondary cone segments radially expand the tubular member into a circular cross-sectional shape and axially translated through the tubular member.
Another embodiment of the disclosure provides a method for expanding a tubular by disposing a plurality of primary cone segments interleaved with a plurality of secondary cone segments into a tubular member. The primary cone segments are slid along a mandrel in a first direction so as to move the primary cone segments outward and expand the tubular member into a tri-lobe cross-sectional shape. The secondary cone segments are then also slid along the mandrel in a first direction so as to move the secondary cone segments outward and expand the tubular member into a circular cross-sectional shape. The primary and secondary cone segments are then translated through a portion of the tubular member.
For a more detailed description of the embodiments of the present disclosure, reference will now be made to the accompanying drawings.
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
The expandable cone assembly 100 can be shifted from the retracted position shown in
Referring now to
As the primary cone segments 106 are moved outward by the interaction with mandrel 104, they expand the tubular member 114 into a tri-lobe cross-sectional shape, as is shown in
Once the primary cone segments 106 have expanded the tubular 114 into the tri-lobe cross-sectional shape of
During and after the transition of the assembly 100 from the retracted position to the expanded position, each of the cone segments 102 is fully supported on the mandrel. Each primary segment 106 has an inner surface 120 that is in contact with the mandrel 104 and adjacent secondary segments 108. Each secondary segment 108 has an inner surface 122 that is also in contact with the mandrel 104. These contact surfaces allow the cone segments 102 to be fully supported by the mandrel 104, which helps distribute the stresses created during the transition process and during expansion of the tubular 114. Because the cone segments 102 are fully supported by the mandrel 104 slots 110 and tabs 112 serve only to maintain alignment and limit axial offset of the segments and do not bear significant radial loading. In certain embodiments, slots 110 and tabs 112 may be rectangular slots and tabs (as shown in
Referring now to
The expandable cone assembly 200 has a retracted position that is shown in
As transition of the expandable cone assembly 200 is initiated, the cone segments 202 are held in a substantially stationary axial position by engagement of the secondary cone segments 208 with the housing (not shown) and the contact between the primary cone segments 206 and the inner diameter of the tubular member 214. The relative axial translation of the mandrel 204 causes the primary cone segments 206 to move radially outward and expand the tubular member 214. The tubular member 214 is initially expanded into a tri-lobe cross-sectional shape, as is shown in
As discussed above, the force needed to transition the assembly 200 from the retracted position to the expanded position is reduced as compared to conventional adjustable cone systems. Therefore, systems utilizing the expandable cone assembly 200 do not need specialized actuators or specialized tubular sections for the transition of the assembly from the retracted to the expanded position.
Referring now to
The expansion assembly 300 and expandable tubular 310 are disposed in a wellbore (not shown). The expansion assembly 300 may be configured to allow fluid circulation from the drill pipe 318 and through the float shoe 316 into the wellbore to support circulation during running and cementing operations. To begin the expansion process, a valve located in the float shoe 316 is closed, such as by dropping a ball or dart, isolating the interior of the expandable tubular 314 from the wellbore.
Pressurized fluid is pumped through the drill pipe 318 and into the expandable tubular 314 at a location between the cup seals 304 and the float shoe 316. The cup seals 304 sealingly engage the expandable tubular 314 so that pressurized fluid is contained within the expandable tubular between the cup seals 304 and the float shoe 316. As the pressure in the expandable tubular 314 increases, the casing lock 306 releases and the expansion assembly 300 can move relative to the expandable tubular 314. The cone lock 302 remains engaged with the expandable tubular 314 and acts to hold then housing 320 and the cone segments 202 in place as mandrel 204 is moved upward by the pressure acting on the cup seals 304.
As previously described, movement of the mandrel 204 upward relative to the cone segments 202 transitions the cone segments from a retracted position to an expanded position. Once the expandable cone assembly 200 is fully expanded, the cone lock 302 disengages from the tubular 314 and pressurized fluid within the tubular will move the expansion assembly 300 through the tubular. The expandable cone assembly 200 radially expands the tubular 314 as the expansion assembly 300 moves through the tubular.
Once expansion of the expandable tubular 314 is complete, the expandable cone assembly 200 can be transitioned back to a retracted position. The expandable cone assembly 200 is retracted by reengaging the tubular 314 with the cone lock 302 and then moving the mandrel 204 downward so that the cone segments 202 can retract. The casing cutter 312 can be used to detach any unexpanded portions of the tubular 314 from the expanded portions and the expansion assembly 300 can be retrieved from the wellbore.
The foregoing has outlined features of several embodiments so that those skilled in the art may better understand the present disclosure. Those skilled in the art should appreciate that they may readily use the present disclosure as a basis for designing or modifying other processes and structures for carrying out the same purposes and/or achieving the same advantages of the embodiments introduced herein. Those skilled in the art should also realize that such equivalent constructions do not depart from the spirit and scope of the present disclosure, and that they may make various changes, substitutions and alterations herein without departing from the spirit and scope of the present disclosure.
