US20040194970A1

US20040194970A1 - Expandable seal member with shape memory alloy

Info

Publication number: US20040194970A1
Application number: US10/408,794
Authority: US
Inventors: William Eatwell; Zheng Xu
Original assignee: Schlumberger Technology Corp
Current assignee: Schlumberger Technology Corp
Priority date: 2003-04-07
Filing date: 2003-04-07
Publication date: 2004-10-07

Abstract

An apparatus, system, and method useful for providing a seal with a surface includes a seal assembly having a seal body constructed at least partially of elastomeric material and at least one shape memory alloy (SMA) wire. The SMA wire is capable of encouraging at least part of the seal body into engagement with the surface.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to methods, apparatus, and systems involving the use of a seal member constructed at least partially of elastomeric material and which is at least partially energized with the use of shape memory alloy.

2. Description of Related Art

Various operations involve the formation of a seal between a device and an adjacent surface. To create a temporary seal, devices are often equipped with one or more expandable/retractable seal members constructed at least partially of elastomeric material. When the sealing member is in a retracted position, the device is movable into position. After the seal member is positioned as desired, the expandable portion of the seal member is expanded to engage the adjacent surface and form the seal.

In the petroleum exploration and recovery industries, for example, it is often necessary or desirable to form a seal between various types of downhole tools, or other equipment, and a borehole wall. As used throughout this patent specification and the appended claims, the term “borehole” means and includes any hole, passageway, or area within which a device may be deployed and any items that may be located therein. An example of a borehole is a subsurface wellbore having a casing. In such operations, the tool or other device is equipped with one or more seal members that are expandable to engage the borehole wall. In some instances, the seal member is also retractable. For example, packers are often used to secure the position of tubing or other equipment in a borehole and isolate the borehole above and below the packer to allow one or more treatments to be conducted. A typical packer includes, among other components, one or more elastomeric seal members that are extendable across the space formed between the packer and borehole wall to form a seal.

Oftentimes, however, the seal member does not extend or retract sufficiently, or is unable to obtain or maintain the desired seal, causing problems in operations. For example, if the seal assembly does not extend sufficiently, the desired seal may not be achieved. For another example, if the seal member does not retract sufficiently, it can become damaged, leave undesirable debris in the borehole, or hinder the retrieval of the device from the borehole.

Thus, there remains a need for methods, apparatus, and/or systems having one or more of the following attributes, capabilities or features: sufficiently encouraging, or causing, at least part of a seal member to sealingly engage an adjacent surface; sufficiently encouraging, allowing, or causing at least part of a seal member to disengage or move away from an adjacent surface; sufficiently encouraging, allowing, or causing at least part of a seal member to expand into and contract away from sealing engagement with an adjacent surface; providing a reliable seal between a device and an adjacent wall that will function statically or dynamically to prevent the escape of fluids; providing a reliable seal system that can withstand cyclical loading, extreme pressure changes, and or large thermal movements; enabling the formation of a seal between a device and an adjacent surface without the addition of bulky or excessive components; or any combination thereof.

BRIEF SUMMARY OF THE INVENTION

The present invention includes a seal assembly having a seal member constructed at least partially of elastomeric material and associated with at least one SMA wire. As used throughout the various portions of this patent, the term “SMA wire” and variations thereof means at least one wire or other member of any suitable configuration or shape that is at least partially constructed of, or includes, one-way shape memory alloy (SMA) material, two-way shape memory alloy (TWSMA) material, or similar material which possesses or exhibits shape memory properties as is or becomes known. The principles of SMA and TWSMA technology sufficient to enable persons skilled in the art to make and use the present invention are and will become further known in the art. Some examples of currently available printed publications and patents with further explanation of shape memory technology are U.S. Patent Application Publication No. U.S. 2002/0074742 A1, U.S. Patent Application Publication No. U.S. 2002/0061692 A1, U.S. Pat. No. 5,211,371, U.S. Pat. No. 6,374,608 B1, the printed publication entitled ASME Petroleum Division Smart Materials Forum Presentation Feb. 6, 2002, Dr. Dimitris C. Lagoudas, Texas A&M Shape Memory Alloy Research Team, the article entitled_“Shape Memory and Superelastic Alloys” by Clive Barnes, the article entitled “The Magic Teaspoon with a Memory” available at http://www.grand-illusions.com/spoon.nitinol.html, and all the various additional references cited in the above references that address shape memory allow technology, each of which is hereby incorporated herein by reference in its entirety. For example, U.S. Patent Application Publication No. U.S. 2002/0074742 A1 provides some examples of materials that can be used as SMA or TWSMA material and the use of shape memory technology in a “sealing” application. However, the above references are in no way limiting upon the present invention.

In accordance with the present invention, with the use of shape memory principles, the shape, size, or orientation of the SMA wire is altered, causing or encouraging at least part of the seal assembly to change shape, size, orientation, or position. In some embodiments, for example, the SMA wire is embedded within an elastomeric seal body. The SMA wire is “trained” to change shape, size, or orientation upon the application (or removal) of a stimulus. A change in the shape, size, or orientation of the SMA wire causes the seal body to change shape, size, or orientation. Other sample embodiments are described in the detailed description below.

Accordingly, the present invention includes features and advantages that enable it to advance seal technology. Characteristics and advantages of the present invention described above and additional features and benefits will be readily apparent to those skilled in the art upon consideration of the following detailed description of preferred embodiments and referring to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

For a detailed description of preferred embodiments of the invention, reference will now be made to the accompanying drawings wherein: [0011]
FIG. 1 is a schematic representation of a conventional downhole tool deployed in a borehole; [0012]
FIG. 2 is a partial cross-sectional view of an embodiment of a seal assembly made in accordance with the present invention showing the body of the seal assembly in a non-engaged position; [0013]
FIG. 3 is a partial cross-sectional view of the embodiment of FIG. 2 showing the body of the seal assembly in an engaged position; [0014]
FIG. 4 is an isolated view of an embodiment of an SMA wire that may be used with the seal assembly of FIG. 2 shown prior to being integrated therewith; [0015]
FIG. 5 is an isolated view of another embodiment of an SMA wire that may be used with the seal assembly of FIG. 2 and shown prior to being integrated therewith; [0016]
FIG. 6 is a partial side view of another embodiment of a seal assembly made in accordance with the present invention; [0017]
FIG. 7 is an end view of the embodiment of FIG. 6; [0018]
FIG. 8 is an isolated view of an embodiment of an SMA wire that may be used with the seal assembly of FIG. 6 and shown prior to being integrated therewith; [0019]
FIG. 9 is a partial side view of another embodiment of a seal assembly made in accordance with the present invention; [0020]
FIG. 10 is an end view of the embodiment of FIG. 9; [0021]
FIG. 11 is a sectional view of another embodiment of a seal assembly made in accordance with the present invention showing the body of the seal assembly in a non-engaged position; [0022]
FIG. 12 is a sectional view of the embodiment of FIG. 11 showing the body of the seal assembly in an engaged position; [0023]
FIG. 13 is an isolated and partially exploded view of an embodiment of an SMA wire that may be used with the seal assembly of FIG. 11 shown prior to being integrated therewith; [0024]
FIG. 14 is a partial cross-sectional view of an embodiment of the present invention including the SMA wire of FIG. 13 employed within the central bore of the seal body of FIG. 11; [0025]
FIG. 15 is a sectional view of another embodiment of a seal assembly made in accordance with the present invention showing the body of the seal assembly in a non-engaged position; [0026]
FIG. 16 is a sectional view of the embodiment of FIG. 15 showing the body of the seal assembly in an engaged position; [0027]
FIG. 17 is a partial cross-sectional view of the seal assembly of FIG. 15; [0028]
FIG. 18 is an end view of the seal assembly of FIG. 17; [0029]
FIG. 19 is a partial cross-sectional view of another embodiment of a seal assembly made in accordance with the present invention shown in a borehole in a non-engaged position; [0030]
FIG. 20 is a partial cross-sectional view of the embodiment of FIG. 19 showing the body of the seal assembly in an engaged position; [0031]
FIG. 21 is an isolated view of an embodiment of an SMA wire that may be used with the embodiment of FIG. 19 shown prior to being integrated therewith; [0032]
FIG. 22 is an isolated view of another embodiment of an SMA wire that may be used with the embodiment of FIG. 19 shown prior to being integrated therewith; [0033]
FIG. 23 is a sectional view of another embodiment of a seal assembly made in accordance with the present invention shown in a borehole in a non-engaged position; [0034]
FIG. 24 is a sectional view of the embodiment of FIG. 23 showing the body of the seal assembly in an engaged position; [0035]
FIG. 25 is an isolated view of an embodiment of an SMA wire that may be used with the seal assembly of FIG. 23 shown prior to being integrated therewith; and [0036]
FIG. 26 is an isolated view of another embodiment of an SMA wire that may be used with the seal assembly of FIG. 23 shown prior to being integrated therewith.[0037]

DETAILED DESCRIPTION OF THE INVENTION

Presently preferred embodiments of the invention are shown in the above-identified figures and described in detail below. It should be understood that the appended drawings and description herein are of preferred embodiments and are not intended to limit the invention or the appended claims. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims. In showing and describing the preferred embodiments, like or identical reference numerals are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness. [0038]
As used herein and throughout all the various portions (and headings) of this patent, the terms “invention”, “present invention”, and variations thereof are not intended to mean the claimed invention of any particular appended claim or claims, or all of the appended claims. The subject or topic of each such reference is thus not necessarily part of, or required by, any particular claim(s) merely because of such reference. [0039]
Referring initially to FIG. 1, a [0040] downhole tool 10 is shown. The illustrated tool 10 is a conventional formation interval straddle tool 11 useful for downhole treatment operations, such as formation zone fracturing. The illustrated straddle tool 11 is shown deployed within a borehole 12 in an earth formation 14. The straddle tool 11 may be conveyed into the borehole 12 on tubing, such as coiled, or jointed, tubing 16, or by any other suitable component(s) or technique. In the example shown, the straddle tool 11 is positioned adjacent to a selected formation interval 18 of the earth formation 14 accessible through numerous perforations 22 formed in a casing 20 in the borehole 12.
Once the illustrated [0041] straddle tool 11 is positioned within the borehole 12 as desired, anchor slips 24 carried on the straddle tool 11 are deployed to lock the straddle tool 11 in the casing 20. To isolate two or more zones in the borehole 12, one or more packers 26, which are also carried on the straddle tool 11, are moved into engagement with the casing 20. In the particular example shown, the straddle tool 11 has upper and lower packers 26, each including an expandable cup seal 27 extending around the circumference of the straddle tool 11. The body of the cup seal 27 is constructed of any suitable material, such as elastomeric material. As used throughout this patent, the term “elastomeric” and variations thereof means constructed at least partially of one or more elastomers or any other suitable material having sealing properties similar to elastomers.
Still referring to FIG. 1, the open ends [0042] 29 of the cup seals 27 are arranged to face each other, and a straddle zone 30 is formed in the borehole 12 between the packers 26. When pressurized fluid is pumped into the exemplary straddle tool 11, the pressure of such fluid exiting one or more ports 28 formed in the tool 11 causes the open end 29 of each cup seal 27 to expand and engage the casing 20, effectively isolating the straddle zone 30 and upper and lower zones 32, 34 of the borehole 12. Relieving the pressure in the straddle zone 30 will cause the cup seals 27 to contract and disengage from the casing 20.
It should be understood that the components, operation, and other details of the formation [0043] interval straddle tool 11 and downhole environment described above and shown in FIG. 1 are provided for illustrative purposes only and are not required for the present invention. Thus, nothing in the detailed description above or shown in FIG. 1 is limiting upon the present invention or the appended claims. Moreover, the present invention, embodiments of which will be described below, is not limited to use in a subsurface well, in connection with formation interval straddle tools, packers, or any other particular device.
Now referring to FIG. 2, an embodiment of the present invention including a [0044] seal assembly 40 having a seal body 44 and a SMA wire 48 is shown. In this example, the body 44 of the seal assembly 40 is formed as a cup seal 27 for use as a packer 26 on a downhole tool 10, such as generally described above with respect to the formation interval straddle tool 11 of FIG. 1. The tool downhole tool 10 is shown disposed within a borehole 12.
The illustrated [0045] seal body 44 is constructed of elastomeric material and extends around the circumference of the downhole tool 10. The illustrated SMA wire 48 is constructed of material suitable for use as heat, or electrically, actuated SMA wire, as is or becomes known. The SMA wire 48 is embedded, or molded, into the seal body 44 and extends around the circumference of the seal body 44. At least one end 50 of the SMA wire 48 is connected with a heat, or electric power, source 56. The heat source 56 may include any desired component(s) to allow the controlled supply and shut-off of heat, or electric current, to the SMA wire 48 as is or becomes known, such as a battery, electronics, pressure-actuated switch, or a combination thereof. In the embodiment shown, the heat source 56 is contained in a cavity 64 within the downhole tool 10. However, the heat source 56 may be located anywhere as desired, such as within the seal assembly 40 or another component, or above the earth's surface (not shown).
Still referring to the embodiment of FIG. 2, the [0046] SMA wire 48 is pre-programmed or trained based upon SMA principles, configured, and associated with the seal body 44 so that upon the application or removal of sufficient heat or electrical power to the SMA wire 48, the SMA wire 48 will move or expand radially (outwardly) relative to the downhole tool 10, energizing at least part of the seal body 44 by causing it to move or expand radially. In the embodiment shown, the heating of the SMA wire 48 will cause the seal body 44 to move to an expanded position or state sufficient to sealingly engage the adjacent surface 15 (the wall 13 of the borehole 12), as shown in FIG. 3.
If desired, the [0047] SMA wire 48 may be trained or pre-programmed and embedded in the seal body 44 in a compressed, or loaded, state. Such configuration may, for example, be used to enable or encourage the expansion or radial movement of the seal body 44, and/or allow for a large radial expansion ratio of the seal body 44 and a high circumferential force by the sealing portion of the body 44 against the borehole wall 13. In the embodiment shown, the SMA wire 48 is embedded in the seal body 44 in a compressed state to cause the radial expansion of the seal body 44.
The [0048] SMA wire 48 may be shaped in any manner sufficient to achieve the desired action. For example, FIG. 4 shows the SMA wire 48 formed in a frame configuration, which may be most suitable for low pressure containment. FIG. 5 shows the SMA wire 48 in a potentially stronger slat ribbon configuration, which may be more suitable for high pressure containment.
Referring back to FIG. 2, the [0049] seal assembly 40 may, if desired, be designed, shaped, pre-programmed, and associated with the seal body 44 so that upon the opposite heat stimulus to the SMA wire 48, the SMA wire 48 will contract, causing, encouraging, or allowing the seal body 44 to contract or move away from the adjacent surface 15. In the embodiment shown, the cooling of the SMA wire 48 will cause the seal body 44 to move into a non-expanded position away from the wall 13 of the borehole 12.
Another embodiment of a [0050] seal assembly 40 in accordance with the present invention is shown in FIGS. 6 and 7. In this example, the seal body 44 of the seal assembly 40 include a tubular member 70 capable of sealing between an elongated carrier and an adjacent, or circumferentially surrounding, surface.
The [0051] tubular member 70 of this embodiment includes an expandable section 72 constructed at least partially of elastomeric material and with which the SMA wire 48 (FIG. 7) is associated. Similarly as described above with respect to FIG. 2, the SMA wire 48 is constructed of material suitable for use as a heat, or electrically, actuated SMA wire as is or becomes known. Also similarly, at least one end of the SMA wire 48 is connected with a heat or electric source, such as described above with respect to FIG. 2. The SMA wire 48 of this example extends around the entire circumference of the expandable section 72.
Still referring to the embodiment of FIG. 6, the [0052] SMA wire 48 is pre-trained programmed or trained so that the SMA wire 48 will expand radially upon the application or removal of sufficient heat, or electrical power, to the SMA wire 48, causing the expandable section 72 to move or expand radially. FIGS. 9 and 10 show the SMA wire 48 and the expandable portion 72 of the seal body 44 in an expanded state, the expandable section 72 being capable of abutting, or engaging, an adjacent surface.
If desired, the [0053] SMA wire 48 may be embedded in the seal assembly 40 in a compressed, or loaded, state, such as to encourage or cause the expansion of the expandable section 72 of the seal body 44 and its sealing engagement with an adjacent surface. For example, the SMA wire 48 of FIG. 7 is shown having wire folds 52 and is thus embedded in a radially compressed state. The expandable section 72 of the seal body 44 may, if desired, be formed having at least one compressed portion. For example, the expandable section 72 of FIGS. 6 and 7 is shown in an initial or non-expanded state having waves, or folds, 76. The illustrated expandable section 72 thus moves in a generally umbrella-like manner.
The [0054] SMA wire 48 of this embodiment may be shaped in any manner sufficient to achieve the desired action. For example, FIG. 8 shows the SMA wire 48 formed in a frame configuration. If desired, the seal assembly 40 can also be designed so that upon the opposite heat or electric stimulus, the SMA wire 48 will contract, causing the seal body 44 to retract. In the embodiment shown, the cooling of the SMA wire 48 will cause the expandable section 72 of the seal body 44 to contract and move away from an adjacent surface.
Another embodiment of a [0055] seal assembly 40 in accordance with the present invention is shown in FIG. 11. In this example, the seal body 44 includes an elongate member 74 constructed at least partially of elastomeric material and capable of sealing between carrier member 80 and a surface 82.
The [0056] SMA wire 48 of this embodiment is at least partially coil, or helically, shaped and either contained within the elongate member 74 or engageable with the inner surface 75 (see FIG. 14) of the elongate member 74. Similarly, as described above with respect to FIG. 2, the SMA wire 48 is constructed of material suitable for use as a heat or electrically actuated SMA wire and is connected at one or more ends 50 with a heat, or electric source (not shown).
Still referring to the embodiment of FIG. 11, the [0057] SMA wire 48 is pre-programmed or trained, configured, and associated with the seal body 44 so that upon the application or removal of sufficient heat or electrical power, the SMA wire 48 will move or expand outwardly, causing the elongate member 74 to move or expand outwardly. In FIG. 12, the SMA wire 48 and elongate member 74 are shown in expanded states, the elongate member 74 sealingly engaging the surface 82 around the circumference of the seal body 44.
The [0058] SMA wire 48 may, if desired, be pre-programmed and embedded in the seal assembly 40 in a compressed state or with “slack” in its length, so as to allow or encourage the expansion or movement of the elongate member 74 of the seal body 44. In FIG. 13, for example, the SMA wire 48 includes segments 54 having an “S” shape in a non-expanded, or initially embedded state. Upon sufficient stimulus, the wire segments 54 will-straighten out, causing the SMA wire 48 and thus the elongate member 74 to expand radially.
The [0059] seal assembly 40 may, if desired, be designed and configured so that, upon the opposite heat or electric stimulus to the SMA wire 48, the SMA wire 48 will contract, causing or allowing the elongate member 74 to retract and move to a non-expanded state (e.g. FIG. 11). In this example, similar to the embodiments above, heating of the SMA wire 48 causes expansion, while cooling causes contraction of the SMA wire 48.
FIGS. 15 and 16 illustrate another embodiment of a [0060] seal assembly 40 in accordance with the present invention. In this example, the seal assembly 40 includes a seal body 44 having an elastomeric tube-like member 84 capable of sealing between a carrier member 80 and a surrounding wall 83. Similarly, as described above with respect to FIG. 2, the SMA wire 48 of this embodiment is constructed of material suitable for use as a heat or electrically actuated SMA wire and connected at at least one end 50 (e.g. FIG. 17) with a heat, or electrical source (not shown).
In this embodiment, an [0061] end member 86 is associated with each end 85 of the tube-like member 84. For example, a disk-shaped end member 88 may abut each end 85 of the tube-like member 84. The SMA wire 48 is engaged with and extends between the end members 86 (see e.g. FIG. 17),
and extends through the center bore [0062] 92 (see e.g. FIGS. 17, 18) of the tube-like member 84. For example, the SMA wire 48 may be woven between the end members 86. In FIG. 18, the SMA wire 48 is shown looped around tabs 90 located on the outer edge of each end member 86.
Now referring to FIGS. 15 and 17, the [0063] SMA wire 48 of this example is designed so that upon the application or removal of sufficient heat or electric power, the SMA wire 48 will contract, drawing the end members 86 toward one another. The end members 86 will squeeze, or push, the opposing ends 85 of the elastomeric tube-like member 84 toward each other, compressing the tube-like member 84 and forcing it to expand or move radially outwardly. In FIG. 16, the tube-like member 84 is shown in an expanded state and sealingly engaged with the wall 83. Upon the opposite heat or electric stimulus, the SMA wire 48 will expand, causing, encouraging, or allowing the tube-like member 84 to contract and return to a non-sealingly engaged state.
While the above embodiments all involve SMA wire that is trained or programmed to change shape, size, or orientation based upon the application or removal of heat or electric power, the SMA wire may be trained and actuated to change shape, size, or orientation using any other methodology that is or becomes known. For example, the SMA wire may be trained based upon super-elastic or other properties. In the embodiment of FIG. 19, the [0064] seal assemblies 40 include at least one SMA wire 48 that changes shape, size, or orientation based upon its super-elastic properties. The seal assemblies 40 of this example are formed as cup seals 27 for use as packers 26 on a downhole tool 10, such as described above with respect to the formation interval straddle tool of FIG. 1.
Still referring to the embodiment of FIG. 19, the [0065] downhole tool 10 is shown disposed in a borehole 12. The seal body 44 of each seal assembly 40 is constructed of elastomeric material and extends around the circumference of the downhole tool 10. A plurality of SMA wires 48 is included in each seal assembly 40. The SMA wires 48 of each plurality are at least partially embedded or molded into the respective seal body 44 and are positioned in spaced relationship with each other around the circumference of the seal assembly 40. For example, the SMA wires 48 are shown in the frame configuration 49 in FIG. 21 and in a slat ribbon configuration in FIG. 22.
Referring back to FIG. 19, the [0066] SMA wires 48 of this embodiment are attached at one end to a base 100. The base 100 may be any suitable component. For example, each base 100 maybe a metal ring 102. The SMA wires 48 are designed so that upon the application or removal of sufficient pressure to the SMA wires 48, the SMA wires 48 will expand, or push, outwardly, encouraging or causing the seal body 44 of each seal assembly 40 to move or expand radially. In this embodiment, the application of pressure causes the expansion of the SMA wires 48. The pressure may be provided in any suitable manner. For example, fluid pressure may be provided in the straddle zone 30 between the seal assemblies 40. FIG. 20 shows the SMA wires 48 and seal bodies 44 in expanded states, the seal bodies 44 abutting, or engaging, the wall 13 of the borehole 12. If desired, the seal assemblies 40 may be designed so that upon the opposite pressure influence on the SMA wires 48, the SMA wires 48 will contract, encouraging or causing the seal body 44 of each seal assembly 40 to move away from the wall 13 of the borehole 12. This occurs in the embodiment shown upon the removal of sufficient fluid pressure in the straddle zone 30.
Referring now to FIG. 23, another embodiment of the present invention includes a [0067] seal assembly 40 having at least one SMA wire 48 that changes shape, size, or orientation based upon the application and removal of pressure as is or becomes known. In this example, the seal body 44 includes an elastomeric, expandable, tube-shaped portion 108 that is engageable with an adjacent surface 112. Two opposing sets 116 of SMA wires 48 are at least partially embedded or molded into seal body 44 of the seal assembly 40. Each set 116 of SMA wires 48 is attached at one end to a support member 100. The support members 100 may be any suitable component. For example, each support member 100 may be a metal ring 102.
Each [0068] individual SMA wire 48 is positioned in spaced relationship with the other SMA wires 48 of the same set 116 around the circumference of the seal assembly 40. For example, the SMA wires 48 of either set may be positioned as shown in the frame configuration of FIG. 25 or the slat ribbon configuration 49 of FIG. 26.
Referring back to FIG. 23, the [0069] SMA wires 48 are pre-programmed and configured so that upon a desired change in pressure on the SMA wires 48, the SMA wires 48 expand or push radially outwardly, causing the tube-shaped portion 108 of the seal body 44 to expand or move radially. FIG. 24 shows the SMA wires 48 and tube-shaped portion 108 of the seal body 44 in expanded positions, the tube-shaped portion 108 abutting the surface 112. The pressure for actuating the SMA wires 48 may be provided in any suitable manner. For example, fluid pressure may be provided in the central bore 110 of the tube-shaped portion 108.
If desired, the [0070] SMA wires 48 may also be capable of contracting upon the opposite pressure influence, causing the tube-shaped portion 108 of the seal body 44 to contract and move away from the surface 112. In the embodiment shown, the SMA wires 48 contract upon the removal of sufficient pressure in the central bore 110 of the tube-shaped portion 108.
With regard to all of the above embodiments, while the [0071] SMA wire 48 is described as being embedded or molded into the seal body 44 of the respective seal assembly 40, the SMA wire 48 may instead be contained in, or otherwise associated with, the body 44 in any suitable manner. For example, depending upon the embodiment, the SMA wire 48 may be contained in a pocket, or cavity, formed in the seal assembly 40. For another example, the SMA wire 48 may be located below, or adjacent to, the part of the seal assembly 40 the it will energize. Thus, the present invention is not limited to having the SMA wire 48 embedded, or molded, within the seal assembly 40.
In another aspect, the [0072] SMA wire 48 of the present invention is not limited to any particular type or method of shape memory actuation or stimulation, or by the type of material used to form the SMA wire. It should also be understood that in some embodiments, the SMA wire 48 is alone capable of sufficiently causing the shape, size, or position of all, or part, of a seal assembly 40 to change. In other embodiments, the SMA wire 48 is used in combination with another one or more mechanism or technique for affecting the shape, size, or position of all, or part, of the seal assembly 40. For example, a seal assembly 40 having SMA wire 48 in accordance with the present invention may be used to supplement the seal energizing mechanism shown in FIG. 1.
Also with respect to the above and any other embodiments of the present invention, the [0073] seal assembly 40 and seal body 44 may be only partially constructed of elastomeric material and formed in any suitable shape. Further, the SMA wire 48 may be associated with only part of the length or circumference of the seal assembly 40 or seal body 44. For example, it may be desirable to cause only a portion of the seal body 44 to engage a surrounding wall along only part of the circumference of the seal assembly 40.
While many of the above embodiments are described in the general context of use on downhole devices, the present invention is applicable to elastomeric seals for dynamic, or static, uses in general. A few examples of other uses for the present invention include shafts, pipes, couplings, joints, flanges, pistons, and bores. [0074]
The present invention does not require each of the techniques or acts described above, and is in no way limited to the above-described methods of operation. Further, the methods described above and any other methods which may fall within the scope of any of the appended claims may be performed in any desired suitable order and are not necessarily limited to the sequence described herein or as may be listed in any of the appended claims. Yet further, the methods of the present invention do not require use of the particular embodiments shown and described in the present specification, but are equally applicable with any other suitable structure, form and configuration of components. [0075]
The present invention includes additional features, capabilities, functions, methods, uses and applications that have not been specifically addressed herein but are, or will become, apparent from the description herein, and the appended drawings and claims. Preferred embodiments of the present invention thus offer advantages over the prior art and are well adapted to carry out one or more of the objects of the invention. [0076]
The present invention does not require all of the above features and aspects. Any one or more of the above features or aspects may be employed in any suitable configuration without inclusion of other such features or aspects. Further, while preferred embodiments of this invention have been shown and described, many variations, modifications, and/or changes of the apparatus and methods of the present invention, such as in the components, details of construction and operation, arrangement of parts, and/or methods of use, are possible, contemplated by the patentee, within the scope of the appended claims, and may be made and used by one of ordinary skill in the art without departing from the spirit or teachings of the invention and scope of appended claims. All matter herein set forth or shown in the accompanying drawings should thus be interpreted as illustrative and not limiting. Accordingly, the scope of the invention and the appended claims is not limited to the embodiments described and shown herein. [0077]

Claims

1. An apparatus for providing a seal between a device and an adjacent surface, the apparatus disposed upon the device, the apparatus comprising:

at least one elastomeric seal member; and

at least one shape memory alloy (SMA) wire associated with said at least one elastomeric seal member and capable of encouraging said at least one elastomeric seal member into engagement with the adjacent surface.

2. The apparatus of claim 1, wherein the device is a downhole tool and the adjacent surface is a borehole wall.

3. The apparatus of claim 2, wherein the downhole tool is a retrievable packer.

4. The apparatus of claim 3, wherein said at least one elastomeric seal member is a cup seal.

5. The apparatus of claim 1, wherein said at least one SMA wire is disposed within said at least one elastomeric seal member.

6. The apparatus of claim 5, wherein said at least one SMA wire is embedded within said at least one elastomeric seal member.

7. The apparatus of claim 1, wherein said at least one elastomeric seal member has a tubular cross-section.

8. The apparatus of claim 7, wherein said at least one elastomeric seal member has a central bore, and wherein said at least one SMA wire is located within said central bore.

9. The apparatus of claim 8, wherein said at least one elastomeric seal member has first and second ends, further including first and second end members engageable with said first and second ends of said at least one elastomeric seal member, respectively, wherein said at least one SMA wire is engaged between said first and second end members, whereby upon at least one among the application and removal of a stimulus to said at least one SMA wire, said at least one SMA wire contracts, causing said first and second end members to compress said at least one elastomeric seal member and urge said at least one elastomeric seal member into engagement with the adjacent surface.

10. The apparatus of claim 7, further including a plurality of SMA wires associated with said at least one elastomeric seal member.

11. The apparatus of claim 10, further including first and second adjacent sets of SMA wires.

12. The apparatus of claim 1, wherein a change in at least one among the shape, size, and orientation of said at least one SMA wire encourages said at least one elastomeric seal member into engagement with the adjacent surface.

13. The apparatus of claim 12, wherein the change in at least one among the shape, size, and orientation of said at least one SMA wire is caused by at least one among the heating and cooling of said at least one SMA wire.

14. The apparatus of claim 12, wherein the change in at least one among the shape, size, and orientation of said at least one SMA wire is caused by at least one among the application and removal of pressure to said at least one SMA wire.

15. The apparatus of claim 1, wherein said at least one SMA wire is capable of encouraging said at least one elastomeric seal-member out of engagement with the adjacent surface.

16. The apparatus of claim 15, wherein a change in at least one among the shape, size, and orientation of said at least one SMA wire encourages said at least one elastomeric seal member out of engagement with the adjacent surface.

17. The apparatus of claim 15, wherein said at least one SMA wire is capable of causing said at least one elastomeric seal member to move into and out of engagement with the adjacent surface.

18. A seal assembly for providing a seal between a downhole tool and a subsurface borehole wall, the seal assembly disposed upon the downhole tool, the seal assembly comprising:

a seal member constructed at least partially of elastomeric material; and

at least one shape memory alloy (SMA) wire associated with said seal member and capable of encouraging at least part of said seal member into and out of sealing engagement with the borehole wall.

19. The seal assembly of claim 18, wherein said at least one SMA wire is formed in a frame configuration.

20. The seal assembly of claim 19, wherein said at least one SMA wire is constructed of one-way shape memory alloy.

21. The seal assembly of claim 18, wherein said at least one SMA wire is formed in a slat ribbon configuration.

22. The seal assembly of claim 18, wherein said at least one SMA wire has a coil shape.

23. The seal assembly of claim 18, wherein said at least one SMA wire is disposed within said seal member in a compressed state.

24. The seal assembly of claim 23, wherein said at least one SMA wire is constructed of two-way shape memory alloy.

25. The seal assembly of claim 18, wherein a change in at least one among the shape, size, and orientation of said at least one SMA wire causes said seal member to move into engagement with the borehole wall.

26. The seal assembly of claim 25, wherein the change in at least one among the shape, size, and orientation of said at least one SMA wire is caused by at least one among the heating and cooling of said at least one SMA wire.

27. The seal assembly of claim 18, wherein said at least one SMA wire is capable of causing said seal member to move away from the borehole wall.

28. The seal assembly of claim 27, wherein said at least one SMA wire is embedded within said seal member.

29. The seal assembly of claim 28, wherein said seal member moves into and out of engagement with the borehole wall in an umbrella-like manner.

30. A seal assembly comprising:

a seal body, at least a portion of which is constructed of elastomeric material; and

at least one shape memory alloy (SMA) wire associated with said seal body, whereby the modification of at least one among the shape, size, and orientation of said at least one SMA wire based upon shape memory principles encourages a change in at least one among the shape, size, and orientation of at least part of said seal body.

31. The seal assembly of claim 30, wherein said seal body is capable of sealingly engaging an adjacent surface, wherein the modification of at least one among the shape, size, and orientation of said at least one SMA wire based upon shape memory principles causes at least part of said seal body to engage the adjacent surface.

32. The seal assembly of claim 31, wherein the seal assembly is disposed upon a downhole tool and the adjacent surface is a borehole wall.

33. The seal assembly of claim 32, wherein said at least one SMA wire is capable of encouraging at least part of said seal body to disengage the adjacent surface.

34. The seal assembly of claim 33, wherein said at least one SMA wire is at least partially embedded within said seal body.

35. A seal assembly useful for creating a temporary seal between a device and a borehole wall, the seal assembly carried upon the device, the seal assembly comprising:

a seal body constructed at least partially of elastomeric material; and

at least one shape memory alloy (SMA) wire associated with said seal body, wherein a change in at least one among the shape, size, and orientation of said at least one SMA wire caused by the application of a stimulus to said at least one SMA wire causes at least part of said seal body to sealingly engage the borehole wall.

36. The seal assembly of claim 35, wherein said stimulus is heat.

37. The seal assembly of claim 35, wherein said stimulus is pressure.

38. The seal assembly of claim 35, whereby the application of the stimulus to said at least one SMA wire causes said at least one SMA wire to expand radially, causing at least part of said seal body to expand radially.

39. The seal assembly of claim 38, whereby the removal of the stimulus from said at least one SMA wire causes said at least one SMA wire to contract radially, encouraging at least part of said seal body to move away from the borehole wall.

40. The seal assembly of claim 39, wherein said at least one SMA wire is embedded within said seal body.

41. The seal assembly of claim 40, wherein the device is a retrievable packer.

42. A method for providing a seal between a device and an adjacent surface with the use of a seal assembly disposed upon the device, the seal assembly including at least one seal member constructed at least partially of elastomeric material and at least one SMA wire, the method comprising:

training the at least one SMA wire to change at least one among its shape, size, and orientation upon at least one among the application and removal of a stimulus to the at least one SMA wire based upon shape memory principles;

associating the at least one SMA wire with the at least one seal member;

providing a stimulus to the at least one SMA wire to cause a change in at least one among the shape, size, and orientation of the SMA wire; and

the SMA wire, by changing at least one among its shape, size, and orientation, encouraging at least part of the seal member to change at least one among its shape, size, and orientation.

43. The method of claim 42, wherein the device is a downhole tool and the adjacent surface is a borehole wall, and further comprising embedding the at least one SMA wire within the at least one seal member.

44. The method of claim 43, wherein providing the stimulus to the at least one SMA wire causes the at least one SMA wire to expand radially, the at least one SMA wire causing at least part of the seal member to expand radially and engage the borehole wall.

45. The method of claim 44, further including providing a stimulus to the at least one SMA wire to cause the at least one SMA wire to contract radially, the at least one SMA wire causing at least part of the seal member to contract radially and move away from the borehole wall.

46. The method of claim 45, wherein the stimulus provided to the at least one SMA wire to cause the at least one SMA wire to contract radially includes the removal of heat.

47. The method of claim 45, wherein the stimulus provided to the at least one SMA wire to cause the at least one SMA wire to contract radially includes the removal of pressure.

48. The method of claim 45, wherein the seal member has a tubular cross-section.