Thermally insulated container for use with well intervention tools

Abstract

A thermally insulated container for use in a well intervention tool includes an inner enclosure defining an enclosed volume. An outer enclosure in which the inner enclosure is nested defines an annular space between the inner enclosure and the outer enclosure. At least one structural stiffening member is affixed to or integrally formed with a wall of at least one of the inner enclosure or the outer enclosure. The container has means for sealing the annular space to enable evacuation thereof.

Description

THERMALLY INSULATED CONTAINER FOR USE WITH WELLINTERVENTION TOOLSBackground

[0001] This disclosure relates to the field of well intervention tools. More specifically, the disclosure relates to thermally insulated containers for use in such well intervention tools to enable the tools to operate at elevated temperatures for extended periods of time.

[0002] The term, “well intervention tools” comprises any instrument or device conveyed along the interior of a subsurface well for performing tasks related to drilling, completion and rework or remediation of the well. Conveyance may be performed by, for example, deploying the tool at the end of an armored electrical cable, at the end of a coiled tubing, or by jointed pipe such as drill pipe or completion pipe. In the case of conveyance by coiled tubing or drill pipe, the tool may be deployed during drilling the well.

[0003] Some well intervention tools comprise electronic circuitry in order to control various functions performed by the tool, and / or to make measurements about the well and the earthen formations adjacent to the well Those skilled in the art are aware that many wells, in particular very deep wells and / or wells used to recover geothermal energy expose the electronic circuits in various intervention tools to high temperatures, and in the case of while-drilling operations, may expose the circuits to high amplitude shock and vibration. Furthermore, while-drilling well intervention tools may be subjected to high temperature and shock for extended periods of time, e.g., several weeks.

[0004] It is known in the art to enclose electronic circuits in well intervention tools within a vacuum-insulated container (e.g., Dewar flask). In the case of while-drilling well intervention, using such vacuum insulated containers has proven to be impractical because the structural strength of such vacuum-insulated containers is limited.

[0005] Accordingly, there is a need for improved thermally insulating containers for use with while-drilling well intervention tools, although the scope of the present disclosure is not limited to such tools.Summary

[0006] One aspect of the present disclosure relates to a thermally insulating container that may be used with a well intervention tool. A thermally insulated container according to this aspect of the disclosure includes an inner enclosure defining an enclosed volume. An outer enclosure in which the inner enclosure is nested defines an annular space between the inner enclosure and the outer enclosure. At least one structural stiffening member is attached to a wall of at least one of the inner enclosure or the outer enclosure. The container has means for sealing the annular space to enable evacuation thereof.

[0007] In some implementations, the inner enclosure and the outer enclosure are closed at one longitudinal end and open at an opposed longitudinal end.

[0008] In some implementations, the inner enclosure and the outer enclosure are joined proximate the open longitudinal end by welding to seal the annular space.

[0009] In some implementations, the annular space is sealed at the open end of the inner enclosure and the outer enclosure by a sealing cap having at least a projection extending into the annular space.

[0010] In some implementations, the inner enclosure and the outer enclosure are open at both longitudinal ends, wherein the annular space is sealed at each longitudinal end by a respective sealing cap each having at least a projection extending into the annular space.

[0011] In some implementations, a surface of at least one of the inner enclosure or the outer enclosure comprises a radiationally reflective coating.

[0012] In some implementations, the radiationally reflective coating comprises one or more of polished surface, metal plating, metal film tape, or spray-on coating.

[0013] In some implementations, the at least one structural stiffening member is configured to resist one or more of axial strain, bending strain, torsional strain and hoop strain.

[0014] In some implementations, the at least one structural member is shaped as a helix.

[0015] In some implementations, the at least one structural stiffening member is affixed to one of an outer wall of the inner enclosure or an inner wall of the outer enclosure, and a dimension of the at least one structural member perpendicular to the outer wall or the inner wall being less than a diameter of the annular space.

[0016] Some implementations further comprise an additional structural stiffening member affixed to an opposed one of the outer wall of the inner enclosure and the inner wall of the outer enclosure to which the at least one structural stiffening member is affixed.

[0017] In some implementations, the at least one structural stiffening member and the additional structural stiffening member each has a shape to enable assembly of the inner enclosure to the outer enclosure with the respective structural stiffening members affixed thereto.

[0018] In some implementations, the at least one structural stiffening member at the additional structural stiffening member each comprises a helix.

[0019] In some implementations, the at least one structural stiffening member at the additional structural stiffening member each has a dimension perpendicular to its respective wall such that the at least one structural stiffening member at the additional structural stiffening member do not interfere with each other during assembly of the inner enclosure to the outer enclosure.

[0020] In some implementations, the container is nested inside a supplemental thermal barrier, the supplemental thermal barrier comprises a supplemental inner enclosure nested within a supplemental outer enclosure, wherein a supplemental annular space is defined between the supplemental inner enclosure and the supplemental outer enclosure. The supplemental container has means for sealing the supplemental annular space to enable evacuation thereof.

[0021] Some implementations further comprise at least one structural stiffening member attached to a wall of at least one of the inner supplemental enclosure or the outer supplemental enclosure.

[0022] Some implementations further comprise at least one structural support disposed between an interior of the inner supplemental enclosure and an exterior of the outer enclosure of the inner container.

[0023] In some implementations, the at least one structural support comprises a sphere.

[0024] In some implementations, the sphere comprises plastic.

[0025] A well intervention tool according to another aspect of the present disclosure comprises a housing adapted to traverse a well. A thermally insulated container according to the foregoing aspect of the present disclosure and its various implementations is disposed in the housing. Thermally sensitive components are disposed in the thermally insulated container.

[0026] In some implementations, a material of the inner enclosure, the at least one structural stiffening member and the outer enclosure, and dimensions of the annular space and the at least one structural stiffening member are chosen such that no interference occurs between the at least one structural member and either the inner enclosure or outer enclosure by reason of thermal expansion.

[0027] Other aspects and possible advantages will be apparent from the description and claims that follow.Brief Description of the Drawings

[0028] FIG. 1 shows a cross-sectional view of an example implementation of a vacuum insulated container transverse to a longitudinal axis thereof.

[0029] FIG. 2 shows a cross-sectional view of the example vacuum insulated container of FIG. 1 along a longitudinal axis thereof.

[0030] FIG. 3 shows a closed-end portion of the vacuum insulated container of FIGS. 1 and 2 to illustrate location of certain structural rigidity enhancing features.

[0031] FIG. 4 shows an enlarged view proximate an open longitudinal end of the vacuum insulated container shown in FIG. 2.

[0032] FIG. 5 shows an enlarged view of a part of FIG. 4 to illustrate structural rigidity enhancing features in more detail.

[0033] FIG. 6 is an enlarged view of the closed longitudinal end shown in FIG. 3.

[0034] FIG. 7 is an end view of the vacuum insulated container transverse to the view inFIG. 4.

[0035] FIG. 8 shows an end view of a sealing cap that may be used in some implementations.

[0036] FIG. 9 shows a cross section view transverse to the view in FIG. 8 to illustrate the sealing cap attached to one longitudinal end of the nested inner enclosure and outer enclosure of FIG. 2.

[0037] FIG. 10 shows an enlarged side view of the sealing cap.

[0038] FIG. 11 shows an expanded view of sealing features on the sealing cap.

[0039] FIG. 12 shows sealing barbs formed proximate the longitudinal ends of the inner enclosure and the outer enclosure.

[0040] FIG. 13 shows an example implementation of a vacuum insulated container according to the present disclosure.Detailed Description

[0041] An example implementation of a vacuum insulated container (“container” hereinafter for convenience) according to the present disclosure is shown in cross section view in FIG. 1 at 10. The container 10 may comprise an inner enclosure 13 nested within an outer enclosure 11. The inner enclosure 13 may define an enclosed volume 15 from which temperature difference between the external environment and the enclosed volume 15 are to be isolated from each other. In the present example implementation, one longitudinal end of each of the inner enclosure 13 and the outer enclosure 11 is open. In the present example implementation, the open longitudinal ends of the inner enclosure 13 and the outer enclosure 11 may be attached to each other, e.g., by thermal welding, fusion, chemical welding or any corresponding process, depending on the materials used, so as tosealingly attach corresponding longitudinal ends of the inner enclosure 13 and the outer enclosure 11 to each other. An annular space (see 17 in FIG. 5) between the inner enclosure 13 and the outer enclosure 11 may, by such sealing attachment and by the opposed ends of the enclosure 11, 13 being closed, be evacuated to reduce heat transfer between the environment outside the container 10 and the interior space 15.

[0042] Either or both the inner enclosure 13 and the outer enclosure 11 may be made from metal, metal alloy or other material having strength sufficient to resist differential pressure between the enclosed volume 15 and the annular space 17, and the annular space 17 and the environment external to the outer enclosure 11. Example implementations may be made from, for example and without limitation, metal alloys sold under the trademark INCONEL. INCONEL is a registered trademark of Huntington Alloys Corporation, Huntington, WV.

[0043] Either or both the inner enclosure 13 and the outer enclosure 11 may comprise, on either or both their respective inner and outer surfaces thereof, a radiationally reflective coating to further reduce radiati onal heat transfer between the inner enclosure 13 and the outer enclosure 11. Such coatings may comprise, for example and without limitation polished surfaces, or plating such as with silver, gold or nickel. Other reflective coatings may comprise thin film (e.g., reflective metal) tapes, or spray-on coatings.

[0044] The inner enclosure 13 and the outer enclosure 11 may be formed, for example and without limitation by additive manufacturing (known as “3D printing”), hydroforming, extrusion, machining or any other convenient manufacturing process. It will be appreciated that additive manufacturing may provide certain benefits, for example and without limitation, the capability of readily forming the one or more structural stiffening members 12 when more complex shapes for the foregoing structural stiffening members may be advantageous.

[0045] Referring to FIG. 2, the opposed longitudinal ends of the inner enclosure 13 and the outer enclosure 11, shown generally at 19, may be closed as explained above. In such implementations, an annular space (shown at 17 in FIG. 5) between the inner enclosure 13 and the outer enclosure may be substantially continuous over the entire outer surface of theinner enclosure 13 and inner surface of the outer enclosure 11. As may be observed (in FIG. 5 in more detail) at least one structural stiffening member 12 may be affixed to a wall of either or both of the inner enclosure 13 and the outer enclosure 11. Such structural stiffening member 12 may be affixed to either or both walls of either or both enclosures 11, 13. In the present example implementation, to provide smooth, accessible interior and exterior surfaces for the vacuum insulated container (10 in FIG. 1), such structural stiffening member 12 may be attached to, affixed to or formed with, for the inner enclosure 13, as shown in detail in FIG. 5, on the outer wall of the inner enclosure 13, and thus disposed within the annular space 17 when the enclosures 11, 13 are assembled to each other.

[0046] Still with reference to FIG. 2, at least one structural stiffening member 12 may be, additionally or alternatively, affixed to, attached to or formed with the inner surface of the outer enclosure 11. In some implementations, the at least one structural stiffening member 12 has a thickness or height dimension (the dimension perpendicular to the respective surface of the outer enclosure 11 and / or the inner enclosure 13), which results in what may be referred to as a “gap”, smaller than the diameter or thickness of the annular space (17 in FIG. 5). In this way, the structural stiffening member(s) 12 does (do) not contact the opposed enclosure’s surface and thereby form a thermally conductive path between the inner enclosure 13 and the outer enclosure 11. Although not a limitation on the scope of the present disclosure, it is contemplated that a minimum distance between the most extensive edge of the structural stiffening member(s) 12 and the wall of the adjacent enclosure is at least 0.5 mm to limit heat transfer between the enclosures 13, 11 by radiation.

[0047] “Affixed to” in the present context as it relates to the structural stiffening member 12 may be used to mean any form in which the structural stiffening member 12 is capable of providing the required structural stiffening of the respective inner enclosure 13 and / or outer enclosure 11. Thus, the structural stiffening member 12 may be integrally formed with the inner enclosure 13 and / or the outer enclosure 11, or it may be a separate structure attached to the respective enclosure such as by, without limitation, adhesive, welding, brazing or soldering. In some implementations, the structural stiffening member 12 may,when formed integrally with the respective enclosure, be implemented simply as a change in shape of the wall of the respective enclosure, whereby the wall thickness of the respective enclosure remains substantially constant.

[0048] While the structural stiffening members 12 shown in FIG. 2 and FIG. 5 may have an approximately square cross section, the shape of such cross section is not a limitation on the scope of the present disclosure.

[0049] In some implementations, and referring to FIG. 4, the open longitudinal ends of the inner enclosure 13 and the outer enclosure 11 may be brought together and joined, for example and without limitation by welding, soldering or brazing. In this way the annular space (17 in FIG. 5) may be evacuated. Other implementations for sealing the annular space (17 in FIG. 5) will be explained further below.

[0050] FIG. 3 illustrates that a longitudinal space 21 between the inner enclosure 13 and the outer enclosure 11 at closed longitudinal ends may provide additional locations for structural stiffening members 14, in this instance, interior ribs or related structures to provide the inner enclosure 13 and the outer enclosure 11 with additional structural rigidity. As with the structural stiffening member(s) described with reference to FIGS. 2 and 5, the ribs 14 are short enough to avoid creating a continuous thermally conductive path between the inner enclosure 13 and the outer enclosure 11. A top view of an example arrangement of the ribs 14 may be observed in FIG. 7.

[0051] The one or more structural stiffening members 12 shown in the example implementation of FIG. 2 may be in the form of helices along the longitudinal dimension of the respective enclosure. It will be appreciated by those skilled in the art that helical shape of the one or more structural stiffening members 12 may provide structural stiffening with reference to, for example and without limitation, axial strain, bending strain, torsional strain and hoop strain in combination. Other implementations may comprise different forms or shapes of structural stiffening members 12, depending on the overall configuration of the well intervention tool (not shown) in which the container 10 is to be disposed. For purposes of the scope of the present disclosure, it is only necessary to increase structural rigidity with reference to one type of strain by attaching a suitably shaped structuralstiffening member 12 to either or both the outer enclosure 11 and the inner enclosure 13. Structural stiffening members which counter more than one type of strain are within the scope of the present disclosure.

[0052] Another aspect of the structural stiffening members 12 when attached to both of the enclosures 11, 13 so as to be disposed in the annular space 17 is that the chosen shape of the structural stiffening members 12 enables assembly of the inner enclosure 13 with the outer enclosure 11 with the structural stiffening member 12 already in place. In the present example implementation, helices provide such functionality. Other shapes, such as splines, may provide the same functionality. In other implementations, the thickness of the structural stiffening members 12 and / or the diameter of the annular space 17 may be chosen to avoid interference between stiffening members attached to opposed enclosure walls.

[0053] In some implementations, the dimensions of the gap in the annular space, the materials used and the dimensions of the enclosures and any structural stiffening members may be chosen such that no interference occurs between the inner and outer enclosures or between any structural stiffening member and the opposed enclosure (to which such structural stiffening member is not attached) notwithstanding thermal expansion of the components of the vacuum insulated container (10 in FIG. 1) during use.

[0054] In some implementations, and referring to FIG. 8, sealing the annular space (17 in FIG. 5) may be obtained using a sealing cap 20 to be affixed to one longitudinal end of the container (10 in FIG. 2). The sealing cap 20 may provide thermal insulation for the enclosed volume (15 in FIG. 1) at the open longitudinal end of the container (10 in FIG. 2), and may enable pressure sealed evacuation of the annular space (17 in FIG. 5) without the need to have the inner enclosure 13 and the outer enclosure 11 come into direct contact with each other. Such arrangement avoids causing a thermally conductive path between the inner enclosure 13 and the outer enclosure 11, thereby increasing the insulating capability of the container (10 in FIG. 2). FIG. 9 shows the sealing cap 20 attached to the longitudinal end of the container 10. In general, the sealing cap 20 may be described as engaging the outer enclosure 11, the annular space 17 and the inner enclosure 13 on its longitudinal end so as to seal the enclosed volume 15 and the annular space 17.

[0055] An enlarged side view of the sealing cap 20 is shown in FIG. 10. The sealing cap 20 may comprise an inner seal section 20B having a nominal diameter equal to the inner diameter of the inner enclosure 13 so as to seal it against fluid pressure. An intermediate seal section 20A may be formed and sized to be insertable into the annular space 17 at its longitudinal end so as to seal the annular space against fluid pressure. Beyond the diameter of the intermediate seal section 20A, the sealing cap 20 may engage the longitudinal end of the outer enclosure 11 as explained above. FIG. 11 shows an enlarged view of the foregoing components of the sealing cap 20 and their engagement with the inner enclosure 13, annular space 17 and the outer enclosure 11.

[0056] FIG. 12 shows that the inner enclosure 13 and the outer enclosure 11 may be formed with or may have affixed thereto on either or both their outer and inner surfaces, one or more respective sealing barbs 13A, 12A, which may engage the material from which the sealing cap 20 is formed, so as to retain the sealing cap 20 in place and to improve sealing of both the enclosed volume (15 in FIG. 1) and the annular space 17. Other implementations may use different structures to seal the annular space 17, for example and without limitation, o-rings.

[0057] The above described sealing cap 20 makes possible connecting a plurality of containers 10 end to end. In such implementations, opposed longitudinal ends of both the inner enclosure 13 and the outer enclosure may be shaped the same or similarly, so as to expose the longitudinal end of the annular space (17 in FIG. 5) on both ends of the container. In such implementations, the sealing cap 20 may be “double ended”, that is, the sealing cap 20 may comprise inner and outer seal sections, as explained with reference to FIGS. 8 through 12, extending in longitudinally in opposed directions. In this way, such sealing cap 20 may enable joining two adjacent vacuum insulated containers end to end. In some implementations, all the containers may be “double ended” and a sealing cap as explained with reference to FIGS. 8 through 12 may be used (the single ended implementation) on the longitudinal endmost vacuum insulated containers. In some implementations, the longitudinal endmost vacuum insulated containers may have one closed end, substantially as explained with reference to FIG. 2. In such implementations using double ended flasks (inner 13 and outer 11 enclosures) and double ended sealingcaps 20, it becomes possible to use the annular space (17 in FIG. 1) as a channel or passageway for electrical wiring and / or optical fibers. In such implementations, it becomes possible for the outer diameter of the container (10 in FIG. 1) to occupy substantially all the internal cross-section of a well intervention tool. Such arrangement may provide as large as possible a thermally insulated cross-sectional area within the well intervention tool to dispose heat sensitive devices, e.g., electronic circuits.

[0058] In some implementations, the sealing cap 20 may be made from materials capable of withstanding expected differential pressure when the annular space (17 in FIG. 5) is evacuated, and the expected temperature to which the container (10 in FIG. 1) is to be exposed for extended periods of time (e.g., several weeks). Examples of such materials comprise, without limitation, thermoplastics, fabric or fiber reinforced plastics (FRPs), KEVLAR brand plastic, and elastomers such as silicone rubber. Preferably the chosen materials have very low thermal conductivity and are structurally and compositionally stable at the highest and / or lowest operating temperatures expected.

[0059] Some implementations may comprise nested thermally insulated containers to further reduce heat transfer between the external environment and the enclosed volume 15. Referring to FIG. 13, an example implementation comprising two nested containers is shown. An inner container 10A may be structurally similar to the container described with reference to FIGS. 1 through 7, and in some implementations may comprise a sealing cap as explained with reference to FIGS. 8 through 12. In the present example implementation, the inner container 10A may comprise an inner enclosure 13 nested within an outer enclosure 11 substantially as explained with reference to FIG. 2 so as to define an enclosed volume 15. Inner container 10A may be nested within an outer container 10B. For purposes of identification in the claims that follow, the outer container 10B may be referred to as a “supplemental thermal barrier.”

[0060] The supplemental thermal barrier 10B may comprise an inner enclosure 23 nested within an outer enclosure 21 so as to define an annular space 27. The inner enclosure 23 and outer enclosure 21 of the supplemental thermal barrier 10B may be structurally similar to any of the implementations described with reference to FIGS. 1 through 7, wherein thesizes of the components of the supplemental thermal barrier 10B are chosen to enable the inner container 10A to be nested within the supplemental thermal barrier 10B. Further, the dimensions of the components of the supplemental thermal barrier 10B may be chosen such that an annular space 25 may exist between the outer enclosure 11 of the inner container 10A and the inner enclosure 23 of the supplemental thermal barrier 10B. Such annular space 25 may have disposed therein one or more structural reinforcements 28 such as may be made from high strength, thermally resistant plastic such as KEVLAR brand plastic KEVLAR is a registered trademark of DuPont Construction & Safety, Inc., Wilmington, DE. In some implementations, the structural reinforcements may be in the form of spheres. Such shape may be preferable to minimize the contact area, and thereby limit heat transfer by conduction between the nested containers 10A. 10B. In some implementations, the annular space 25 may be evacuated.

[0061] A well intervention tool according to the present disclosure may comprise a housing adapted to traverse a well. The housing may contain therein thermally sensitive devices, such as electronic circuits. The thermally sensitive devices may be disposed in a thermally insulated container according to the above-described aspects of the present disclosure related to thermally insulated containers.

[0062] A thermally insulated container according to the present disclosure may provide thermal protection for heat sensitive components used in well intervention tools which are subjected to extended time at elevated temperatures and large shock and vibration forces. A well intervention tool having heat sensitive components disposed in a thermally insulated container according to the present disclosure may have greater reliability and longer service time in wells than using thermally insulated containers known in the art prior to the present disclosure.

[0063] In light of the principles and example implementations described and illustrated herein, it will be recognized that the example implementations can be modified in arrangement and detail without departing from such principles. The foregoing discussion has focused on specific implementations, but other configurations are also contemplated. In particular, even though expressions such as in “an implementation," or the like are usedherein, these phrases are meant to generally reference implementation possibilities, and are not intended to limit the disclosure to particular implementation configurations. As used herein, these terms may reference the same or different implementations that are combinable into other implementations. As a rule, any implementation referenced herein is freely combinable with any one or more of the other implementations referenced herein, and any number of features of different implementations are combinable with one another, unless indicated otherwise. Although only a few examples have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible within the scope of the described examples. Accordingly, all such modifications are intended to be included within the scope of this disclosure as defined in the following claims.

Claims

ClaimsWhat is claimed is:

1. A thermally insulated container for use in a well intervention tool, comprising an inner enclosure defining an enclosed volume; an outer enclosure in which the inner enclosure is nested, wherein an annular space is defined between the inner enclosure and the outer enclosure; at least one structural stiffening member affixed to or formed integrally with a wall of at least one of the inner enclosure or the outer enclosure; and means for sealing the annular space to enable evacuation thereof.

2. The container of claim 1 wherein the inner enclosure and the outer enclosure are closed at one longitudinal end and open at an opposed longitudinal end.

3. The container of claim 2 wherein the inner enclosure and the outer enclosure are joined proximate the open longitudinal end by welding to seal the annular space.

4. The container of claim 2 wherein the annular space is sealed at the open end of the inner enclosure and the outer enclosure by a sealing cap having at least a projection extending into the annular space.

5. The container of claim 1 wherein the inner enclosure and the outer enclosure are open at both longitudinal ends, wherein the annular space is sealed at each longitudinal end by a respective sealing cap each having at least a projection extending into the annular space.

6. The container of claim 1 wherein a surface of at least one of the inner enclosure or the outer enclosure comprises a radiationally reflective coating.

7. The container of claim 6 wherein the radiationally reflective coating comprises one or more of polished surface, metal plating, metal film tape, or spray-on coating.

8. The container of claim 1 wherein the at least one structural stiffening member is configured to resist one or more of axial strain, bending strain, torsional strain and hoop strain.

9. The container of claim 8 wherein the at least one structural member is shaped as a helix.

10. The container of claim 1 wherein the at least one structural stiffening member is affixed to one of an outer wall of the inner enclosure or an inner wall of the outer enclosure, a dimension of the at least one structural member perpendicular to the outer wall or the inner wall being less than a gap of the annular space.

11. The container of claim 10 further comprising an additional structural stiffening member affixed to an opposed one of the outer wall of the inner enclosure and the inner wall of the outer enclosure to which the at least one structural stiffening member is affixed.

12. The container of claim 11 wherein the at least one structural stiffening member and the additional structural stiffening member each has a shape to enable assembly of the inner enclosure to the outer enclosure with the respective structural stiffening members affixed thereto.

13. The container of claim 12 wherein the at least one structural stiffening member at the additional structural stiffening member each comprises a helix.

14. The container of claim 12 wherein the at least one structural stiffening member at the additional structural stiffening member each has a dimension perpendicular to its respective wall such that the at least one structural stiffening member at the additional structural stiffening member do not interfere with each other during assembly of the inner enclosure to the outer enclosure.

15. The container of claim 1 wherein the container is nested inside a supplemental thermal barrier, the supplemental thermal barrier comprising: a supplemental inner enclosure nested within a supplemental outer enclosure, wherein a supplemental annular space is defined between the supplemental inner enclosure and the supplemental outer enclosure; and means for sealing the supplemental annular space to enable evacuation thereof.

16. The container of claim 15 further comprising:at least one structural stiffening member attached to a wall of at least one of the inner supplemental enclosure or the outer supplemental enclosure.

17. The container of claim 15 further comprising at least one structural support disposed between an interior of the inner supplemental enclosure and an exterior of the outer enclosure of the inner container.

18. The container of claim 17 wherein the at least one structural support comprises a sphere.

19. The container of claim 18 wherein the sphere comprises plastic.

20. The container of claim 1 wherein a material of the inner enclosure, the at least one structural stiffening member and the outer enclosure, and dimensions of the annular space and the at least one structural stiffening member are chosen such that no interference occurs between the at least one structural member and either the inner enclosure or outer enclosure by reason of thermal expansion.

21. A well intervention tool comprising: a housing adapted to traverse a well; a thermally insulated container disposed in the housing, the thermally insulated container, comprising an inner enclosure defining an enclosed volume, an outer enclosure in which the inner enclosure is nested, wherein an annular space is defined between the inner enclosure and the outer enclosure, at least one structural stiffening member affixed to or formed integrally with a wall of at least one of the inner enclosure or the outer enclosure, and means for sealing the annular space to enable evacuation thereof; and thermally sensitive components disposed in the thermally insulated container.

22. The well intervention tool of claim 21 wherein the inner enclosure and the outer enclosure are closed at one longitudinal end and open at an opposed longitudinal end.

23. The well intervention tool of claim 22 wherein the inner enclosure and the outer enclosure are joined proximate the open longitudinal end by welding to seal the annular space.

24. The well intervention tool of claim 22 wherein the annular space is sealed at the open end of the inner enclosure and the outer enclosure by a sealing cap having at least a projection extending into the annular space.

25. The well intervention tool of claim 21 wherein the inner enclosure and the outer enclosure are open at both longitudinal ends, wherein the annular space is sealed at each longitudinal end by a respective sealing cap each having at least a projection extending into the annular space.

26. The well intervention tool of claim 21 wherein a surface of at least one of the inner enclosure or the outer enclosure comprises a radiationally reflective coating.

27. The well intervention tool of claim 26 wherein the radiationally reflective coating comprises one or more of polished surface, metal plating, metal film tape, or spray-on coating.

28. The well intervention tool of claim 21 wherein the at least one structural stiffening member is configured to resist one or more of axial strain, bending strain, torsional strain and hoop strain.

29. The well intervention tool of claim 28 wherein the at least one structural member is shaped as a helix.

30. The well intervention tool of claim 21 wherein the at least one structural stiffening member is affixed to one of an outer wall of the inner enclosure or an inner wall of the outer enclosure, a dimension of the at least one structural member perpendicular to the outer wall or the inner wall being less than a diameter of the annular space.

31. The well intervention tool of claim 30 further comprising an additional structural stiffening member affixed to an opposed one of the outer wall of the inner enclosure and the inner wall of the outer enclosure to which the at least one structural stiffening member is affixed.

32. The well intervention tool of claim 31 wherein the at least one structural stiffening member and the additional structural stiffening member each has a shape to enable assembly of theinner enclosure to the outer enclosure with the respective structural stiffening members affixed thereto.

33. The well intervention tool of claim 32 wherein the at least one structural stiffening member at the additional structural stiffening member each comprises a helix.

34. The well intervention tool of claim 32 wherein the at least one structural stiffening member at the additional structural stiffening member each has a dimension perpendicular to its respective wall such that the at least one structural stiffening member at the additional structural stiffening member do not interfere with each other during assembly of the inner enclosure to the outer enclosure.

35. The well intervention tool of claim 21 wherein the container is nested inside a supplemental thermal barrier, the supplemental thermal barrier comprising: a supplemental inner enclosure nested within a supplemental outer enclosure, wherein a supplemental annular space is defined between the supplemental inner enclosure and the supplemental outer enclosure; and means for sealing the supplemental annular space to enable evacuation thereof.

36. The well intervention tool of claim 35 further comprising: at least one structural stiffening member attached to a wall of at least one of the inner supplemental enclosure or the outer supplemental enclosure.

37. The well intervention tool of claim 35 further comprising at least one structural support disposed between an interior of the inner supplemental enclosure and an exterior of the outer enclosure of the inner container.

38. The well intervention tool of claim 37 wherein the at least one structural support comprises a sphere.

39. The well intervention tool of claim 38 wherein the sphere comprises plastic.

40. The well intervention tool of claim 21 wherein a material of the inner enclosure, the at least one structural stiffening member and the outer enclosure, and dimensions of the annularspace and the at least one structural stiffening member are chosen such that no interference occurs between the at least one structural member and either the inner enclosure or outer enclosure by reason of thermal expansion.

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