SEAL, METHOD AND SYSTEM

Abstract

A seal, including a seal material, a substructure to which the seal material is attached, the substructure having end rings and a plurality of energizers extending between the end rings. A method for making a seal, including forming a substructure having end rings and a plurality of energizers extending between the end rings in a first position, longitudinally stretching the substructure, reducing an outside diameter of the substructure by the stretching, and disposing a seal material on the stretched substructure. A method for sealing a tubular structure, including disposing a seal in the tubular structure, allowing the substructure to recover the first position, and urging the seal material into contact with the tubular structure. A borehole system, including a borehole in a subsurface formation, a string in the borehole, and a seal disposed within or as a part of the string.

Description

BACKGROUND

In the resource recovery and fluid sequestration industries, Seals are ubiquitously employed to manage differential pressures either uphole or downhole depending upon the particular borehole or process in which the seal is being used. While many seals perform well for their intended function, there are myriad applications where performance is insufficient. The art is always receptive to alternative technologies.

SUMMARY

An embodiment of a seal, including a seal material, a substructure to which the seal material is attached, the substructure having end rings and a plurality of energizers extending between the end rings.

An embodiment of a method for making a seal, including forming a substructure having end rings and a plurality of energizers extending between the end rings in a first position, longitudinally stretching the substructure, reducing an outside diameter of the substructure by the stretching, and disposing a seal material on the stretched substructure.

An embodiment of a method for sealing a tubular structure, including disposing a seal in the tubular structure, allowing the substructure to recover the first position, and urging the seal material into contact with the tubular structure.

An embodiment of a borehole system, including a borehole in a subsurface formation, a string in the borehole, and a seal disposed within or as a part of the string.

BRIEF DESCRIPTION OF THE DRAWINGS

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

FIG. 1 is a perspective view of a seal as disclosed herein in an elongated run-in position;

FIG. 2 is a perspective view of the seal as disclosed herein in a contracted position;

FIG. 3 is a perspective view of a substructure for the seal of FIG. 1;

FIG. 4 is a schematic view of the seal of FIG. 1 in a stretched position in a casing;

FIG. 5 is the seal of FIG. 1 in a sealed position within a casing;

FIGS. 6-9 are a series of views that illustrate the manufacturing sequence for the seal of FIG. 1; and

FIG. 10 is a view of a borehole system including the seal as disclosed herein.

DETAILED DESCRIPTION

A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.

Referring to FIGS. 1 and 2, a seal 10 is illustrated in a run-in position and in an expanded position, respectively. Seal 10 includes a seal material 12 and a substructure 14 movably mounted on a mandrel 16. As illustrated, the particular seal 10 in FIG. 1 includes four substructures 14 disposed adjacent one another on the mandrel 16. More or fewer are contemplated. Each substructure 14 is movable upon the mandrel 16 to either elongate and reduce an outside diameter of the substructure 14 (FIG. 1) or contract and increase the outside diameter of the substructure 14 (FIG. 2). In the position of FIG. 2, the seal material 12 is compressed against a radially outwardly positioned structure such as a casing or open hole.

Referring to FIG. 3, an enlarged perspective view of one of the substructures 14 in FIG. 1 is illustrated. Substructure 14 comprises end rings 18 and 20 and a plurality of energizers 22 extending between and connected to the rings 18, 20. In an embodiment, each energizer 22 of the plurality of energizer includes a first leg 24 and a second leg 26 that are joined by a land 28. In some embodiments, the land 28 may be planar while in others it may radially outwardly convex, for example if the bends 30 and 32 are not particularly sharp, the land 28 will bow radially outwardly somewhat when in the position as shown in FIG. 3. Further, in some embodiments, the legs 24 and 26 include toes 34 and 36 extending from legs 24 and 26 at bends 38 and 40. In such embodiments, the toes 34 and 36 improve ease of attachment of the energizers 22 to the end rings 18 and 20. To be appreciated is that in an embodiment, and illustrated in FIG. 3, each energizer 22 is angled relative to a tangent line (42 for example) to the adjacent ring 18 or 20. Considering a particular toe 36 which is identified with letter E for exemplary, it should be appreciated that there is an angle to that is not parallel to the tangent 42 as might otherwise be expected. It will also be noted that none of the toes 36 or toes 34 are parallel to a tangent to the respective end ring that is nearest each toe. Rather they all have an angle. That angle is from about 3 degrees to about 7 degrees and may be at about 5 degrees in embodiments. The number of degrees is generally related to the thickness of the material used to form the energizers 22 since the purpose of the angle is to create a shingle-type overlap of adjacent energizers 22. The shingle-type overlap ensures that when the substructure 14 is stretched, reducing the outside diameter thereof, the energizers will not bind with one another and become an impediment to the stretching operation. Further, the shingle-type arrangement allows each energizer 22 to be wider and hence when the substructure 14 is fully expanded, there will be no radial gaps between the energizers 22. This is a benefit with regard to creating a competent seal because there are no areas of the seal that are not directly supported.

The substructure 14 may also include a seal groove 46 therein to seal the end rings 18 and 20 to the mandrel 16.

While FIGS. 1 and 2 provided understanding of the run-in and deployed positions of the seal 10, FIGS. 4 and 5 do this schematically within a tubular structure 48 such as a casing. It will be appreciated that the tubular structure 48 is spaced from the seal 10 when the seal is in the run-in or FIG. 1 position while there is no spacing in FIG. 5 wherein the seal 10 is in the sealed or FIG. 2 position. It is also easily seen in FIGS. 4 and 5 that the seal material 12, which may be a fluorinated plastic such as Polytetrafluoroethylene (PTFE), Perfluoroalkoxy alkane (PFA), Fluorinated ethylene propylene (FEP) or rubbery material deforms to fill volumes between the substructures 14.

Referring to FIGS. 6-9, a sequence is shown to form the seal 10. In the first stage, the substructures 14 are formed and assembled (FIG. 6). Whatever number of substructures 14 that is desired are disposed upon the mandrel 16. In stage 2, the substructures 14 are stretched along the mandrel 16 to reduce an outside diameter of the substructures 14 (FIG. 7). With the substructures reduced in outside diameter, the sealing material 12 is bonded to the substructures 14 (FIG. 8). IT is advantageous to bond the sealing material 12 to the substructure 14 while stretched because the substructures are then predisposed to return to the position of FIG. 6, while with the seal material 12 thereon, will appear as that of FIG. 9.

Referring to FIG. 10, a borehole system 50 is illustrated. The system 50 comprises a borehole 52 in a subsurface formation 54. A string 56 is disposed within the borehole 52. A seal 10 as disclosed herein is disposed within or as a part of the string 56.

Set forth below are some embodiments of the foregoing disclosure:

Embodiment 1: A seal, including a seal material, a substructure to which the seal material is attached, the substructure having end rings and a plurality of energizers extending between the end rings.

Embodiment 2: The seal as in any prior embodiment, wherein each energizer of the plurality of energizers includes first and second legs.

Embodiment 3: The seal as in any prior embodiment, wherein each energizer of the plurality of energizers includes a land between the first and second legs.

Embodiment 4: The seal as in any prior embodiment, wherein the land is planar.

Embodiment 5: The seal as in any prior embodiment, wherein the land is curved.

Embodiment 6: The seal as in any prior embodiment, wherein each energizer is positioned at an angle to a line tangent one of the end rings.

Embodiment 7: The seal as in any prior embodiment, wherein the angle is about 5 degrees.

Embodiment 8: The seal as in any prior embodiment, wherein the plurality of energizers are arranged in an overlapping manner.

Embodiment 9: The seal as in any prior embodiment, wherein a number of substructures are disposed longitudinally adjacent one another.

Embodiment 10: The seal as in any prior embodiment, wherein the seal material is a polymer.

Embodiment 11: The seal as in any prior embodiment, wherein the seal material is bonded to the substructure.

Embodiment 12: A method for making a seal, including forming a substructure having end rings and a plurality of energizers extending between the end rings in a first position, longitudinally stretching the substructure, reducing an outside diameter of the substructure by the stretching, and disposing a seal material on the stretched substructure.

Embodiment 13: The method as in any prior embodiment, wherein the reducing includes overlapping the plurality of energizers.

Embodiment 14: The method as in any prior embodiment, wherein the disposing is bonding.

Embodiment 15: The method as in any prior embodiment, wherein the stretching is within an elastic limit of the plurality of energizers.

Embodiment 16: A method for sealing a tubular structure, including disposing a seal as in any prior embodiment in the tubular structure, allowing the substructure to recover the first position, and urging the seal material into contact with the tubular structure.

Embodiment 17: The method as in any prior embodiment further including inputting energy upon the substructure toward the first position.

Embodiment 18: The method as in any prior embodiment further including squeezing the seal material between the substructure and the tubular structure.

Embodiment 19: The method as in any prior embodiment further including creating a plurality of rings of squeezed seal material.

Embodiment 20: A borehole system, including a borehole in a subsurface formation, a string in the borehole, and a seal as in any prior embodiment disposed within or as a part of the string.

The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Further, it should be noted that the terms “first,” “second,” and the like herein do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. The terms “about”, “substantially” and “generally” are intended to include the degree of error associated with measurement of the particular quantity based upon the equipment available at the time of filing the application. For example, “about” and/or “substantially” and/or “generally” can include a range of ±8% a given value.

The teachings of the present disclosure may be used in a variety of well operations. These operations may involve using one or more treatment agents to treat a formation, the fluids resident in a formation, a borehole, and/or equipment in the borehole, such as production tubing. The treatment agents may be in the form of liquids, gases, solids, semi-solids, and mixtures thereof. Illustrative treatment agents include, but are not limited to, fracturing fluids, acids, steam, water, brine, anti-corrosion agents, cement, permeability modifiers, drilling muds, emulsifiers, demulsifiers, tracers, flow improvers etc. Illustrative well operations include, but are not limited to, hydraulic fracturing, stimulation, tracer injection, cleaning, acidizing, steam injection, water flooding, cementing, etc.

While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited.

Claims

1. A seal, comprising: a seal material;a substructure to which the seal material is attached, the substructure having:end rings and a plurality of energizers extending between the end rings.

2. The seal as claimed in claim 1, wherein each energizer of the plurality of energizers includes first and second legs.

3. The seal as claimed in claim 2, wherein each energizer of the plurality of energizers includes a land between the first and second legs.

4. The seal as claimed in claim 3, wherein the land is planar.

5. The seal as claimed in claim 3, wherein the land is curved.

6. The seal as claimed in claim 1, wherein each energizer is positioned at an angle to a line tangent one of the end rings.

7. The seal as claimed in claim 6, wherein the angle is about 5 degrees.

8. The seal as claimed in claim 1, wherein the plurality of energizers are arranged in an overlapping manner.

9. The seal as claimed in claim 1, wherein a number of substructures are disposed longitudinally adjacent one another.

10. The seal as claimed in claim 1, wherein the seal material is a polymer.

11. The seal as claimed in claim 1, wherein the seal material is bonded to the substructure.

12. A method for making a seal, comprising: forming a substructure having end rings and a plurality of energizers extending between the end rings in a first position;longitudinally stretching the substructure;reducing an outside diameter of the substructure by the stretching; anddisposing a seal material on the stretched substructure.

13. The method as claimed in claim 12, wherein the reducing includes overlapping the plurality of energizers.

14. The method as claimed in claim 12, wherein the disposing is bonding.

15. The method as claimed in claim 12, wherein the stretching is within an elastic limit of the plurality of energizers.

16. A method for sealing a tubular structure, comprising: disposing a seal as claimed in claim 1 in the tubular structure;allowing the substructure to recover the first position; andurging the seal material into contact with the tubular structure.

17. The method as claimed in claim 16 further including inputting energy upon the substructure toward the first position.

18. The method as claimed in claim 16 further including squeezing the seal material between the substructure and the tubular structure.

19. The method as claimed in claim 16 further including creating a plurality of rings of squeezed seal material.

20. A borehole system, comprising: a borehole in a subsurface formation;a string in the borehole; anda seal as claimed in claim 1 disposed within or as a part of the string.