Patent Application
20120299246
In the downhole drilling and completions industry packers or seal elements are ubiquitously used for a myriad of sealing and inhibition applications. There are many kinds of sealing elements available in the industry but since conditions encountered are ever changing, the industry is always receptive to new configurations providing sealing capability.
An assembly for reducing a radial gap between radially proximate components including a setting member having a first dimension that partially defines the radial gap, the setting member including a circumferential groove extending radially from the first dimension, and a first toroid having a second dimension, the setting member operatively arranged to engage with the first toroid, wherein increasingly engaging the setting member with the first toroid enables a boundary dimension of the assembly to be extended toward the radial gap for reducing the radial gap, the circumferential groove operatively arranged to catch the first toroid when the setting member is fully engaged with the first toroid.
A system including a pair of assemblies, each assembly including a setting member having a first dimension that partially defines the radial gap, the setting member including a circumferential groove extending radially from the first dimension, and a first toroid having a second dimension, the setting member operatively arranged to engage with the first toroid, wherein increasingly engaging the setting member with the first toroid enables a boundary dimension of the assembly to be extended toward the radial gap for reducing the radial gap, the circumferential groove operatively arranged to catch the first toroid when the setting member is fully engaged with the first toroid, and a plurality of subsequent toroids arranged in a sealing area between the first and second end assemblies.
A method of reducing a radial gap between radially proximate components including engaging a first toroid with a setting member, the setting member at least partially defining the radial gap and having a radially extending circumferential groove, increasingly engaging the setting member with the first toroid, wherein increasingly engaging the first toroid enables a boundary dimension of the assembly to be extended toward the radial gap for reducing the radial gap, and locating the first toroid in the circumferential groove when the setting member becomes fully engaged with the first toroid.
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
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 now to the drawings,
Wedge 14 has an outer dimension 24 and borehole 22 has a dimension 26, with a gap 28 formed between the outer dimension 24 of the wedge 14 and wall 20 of the borehole 22. For example, the dimensions 24 and 26, or any other dimension referred to herein, could be radii, major radii, minor radii, diameters, distances from a reference point, etc. As described in more detail below, a toroid 30 (or a plurality of toroids 30) is included to seal, block, obstruct, close, or otherwise alleviate or prevent extrusion of a sealing element through the gap 28. It is to be appreciated that with reference to the embodiments described herein, the term “toroid” as used herein relates generally to any annular, ring, or donut shaped body, regardless of cross-sectional geometry, and that the body may be solid, hollow, or otherwise hollow, but packed or filled with another material. The toroids described herein are generally stretchable, compressible, durable, resilient, and/or otherwise able to change in shape, size, thickness, etc. When applicable, the term “toroid” is to be interpreted broader than “torus” or “ring”, which both imply circumferential continuity. For example, as used herein, the term “toroid” encompasses bodies that are not only circumferentially continuous, but also bodies which contain a split, break, or open end, for example resembling a ‘c’ shape, such as is common with piston rings or the like. Thus, a toroid may be formed by rotating a cross-sectional shape at least partially about a line, where the line is in the same plane as the shape and does not intersect the shape. For example, the cross-sectional shape of each of the toroids 30 in
The term “wedge” is used herein to refer to the setting member and components or portions of the setting member, because the setting member is illustrated throughout the drawings as having a conical or frustoconical wedge shape. However, it is to be appreciated that the setting member could take various other shapes and arrangements. For example, in lieu of a tapered wedge, the setting member could include: discrete tiers or steps; a rounded bump or bulge; a lever; an inflatable portion, etc., for engaging under, in, or with the toroids in order to pry, stretch, expand, compress, or otherwise alter the shape, size, and/or position of the toroids (i.e., to set the toroids). Furthermore, it is to be appreciated that the setting member does not need to be circumferentially continuous, for example, the setting member could include a plurality of discrete portions (e.g., each having a wedge-shaped cross-section) spaced about a circumference of a mandrel.
The toroids 30 could act alone as a seal in order to isolate between zones of a borehole, or the toroids 30 could act as a backup for preventing a separate sealing element from extruding through the gap 28. In the embodiment of
In order to obstruct the gap 28 for inhibiting or preventing extrusion, the wedge 14 is moved axially in the direction indicated by arrows 35. This axial movement results in the toroids 30 engaging with the wedge and expanding as the wedge is inserted further into the toroids 30. Effectively, this interplay between the wedge 14 and the toroids 30 enables a maximum outer dimension 36 of the assembly 10 to increase in order to block or obstruct the gap 28. In
Wedge 14 also includes a circumferential groove 38 extending radially inwardly from the outer dimension 24 of the wedge 14. In the event that one of the toroids 30 traverses the entirety of the tapered portion of the wedge, and expands over the outer dimension 24 of the wedge, the groove 38 is included to catch that toroid. This locks the toroid to the wedge so that the toroid essentially becomes a part of the wedge, and further toroids that traverse the entirety of the wedge 14 may engage with, and expand around, the locked toroid. This is described in more detail below with respect to
Referring to
Initially, as shown in
By moving the inner wedge 46 axially toward the toroid 62 in the direction indicated by arrows 72 in
Relative movement between the inner wedge 46 and the outer wedge 48 is possible, for example, by the lead toroid 62a blocking forward movement of the outer wedge 48. The radially extending flange 74 of the inner wedge 46 acts as a stop for limiting the amount of relative movement between the inner wedge 46 and the outer wedge 48 by receiving a radially extending flange 82 of the outer wedge 48. Relative movement is also prevented in the opposite direction because the inner wedge 46 and the outer wedge 48 include complementary ratcheting teeth 84. The complementarily arranged ratchet teeth 84 restrict the axial movement of the inner wedge 46 relative to the outer wedge 48 to only the direction indicated by the arrows 72. Thus, once the flange 82 of the outer wedge 48 has contacted the flange 74 of the inner wedge 46, the two wedge portions are essentially locked together such that the shoulders 58 and 60 form a single ramp for expanding the toroids 62 (as shown in
In
Once one of the toroids 62 becomes locked in the groove 86, that toroid effectively becomes part of the wedge device 44. That is, the lead toroid 62a that becomes locked may act like a ramp to essentially increase the size of the wedge device 44, for subsequent toroids, such as a secondary toroid 62b, to engage with and expand around. Similar to the identifiers ‘a’ discussed above, it is to be appreciated that the identifier ‘b’ is used for the sake of discussion only, and any description of toroids 62 generally applies to secondary toroid 62b. Thus, in the embodiment depicted in
A packer device 90 is shown in
Also similar to the assemblies discussed above, the device 90 is located in an annulus 106 formed between a wall 108 of a borehole 110 and an outer surface 112 of the mandrel 92. Additionally, the device 90 is included to engage with toroids 114 in order to cause the toroids 114 to seal, block, obstruct, or close a set of gaps 116 and 118, located between the wall 108 of the borehole 110 and the first and second end assemblies 94 and 96, respectively. A first lead toroid 114a is positioned in front of first end assembly 94 and a second lead toroid 114b is positioned in front of second end assembly 96, with a plurality of other toroids 114 located between the lead toroids 114a and 114b.
The first end assembly 94 operates similarly to the wedge assembly 44. A setting device presses the first end assembly 94 axially in the direction of arrows 120 in order to move the first end assembly 94 along the mandrel 92. Unlike the wedge assembly 44, the first end assembly 94 includes a dog 122 that restricts relative movement between the inner wedge 98 and the outer wedge 100, for example, by being held in an opening 124 of the inner wedge 98 and a notch 126 in the outer wedge 100. Then, when the first end assembly 94 passes over a receiving area 128, the dog 122 can drop out, thereby enabling relative movement between the inner wedge 98 and the outer wedge 100 (at least until the relative movement is restricted again, for example by ratcheting teeth and/or radially extending flanges, as described above with respect to
The inner wedge 98 of the first end assembly 94 is connected to the outer wedge 104 of the second end assembly 96 via a connecting element 130, which could be, for example, a fixed length of stainless steel mesh. Movement of the inner wedge 98 will exert a force on the lead toroid 114a, which will transfer to the outer wedge 104 via the toroids 114 and 114b. Since the inner wedge 98 is fixed to the connecting element 130, movement of the inner wedge 98 will result in the connecting element 130 also moving, which will in turn enable the outer wedge 104 to move in the direction of the arrows 120. The movement of the outer wedge 104 exposes the tapered shoulder of the inner wedge 102 so that second lead toroid 114b can engage with the shoulder of the inner wedge 102 and expand. The inner wedge 102 does not move because it is fixed to the mandrel 92 at an anchor point 132.
Once the dog 122 is released into the receiving area 128 and relative movement between the inner wedge 98 and outer wedge 100 is possible, the inner wedge 98 will move away from the toroids 114, exposing the tapered shoulder of the inner wedge 98 to the toroids 114, thereby enabling the lead toroids 114a to engage with the shoulder of the inner wedge 98 and expand as the inner wedge 98 is inserted therethrough. Inner wedge 98 will be pressed in the direction of the arrows 120 until the gaps 116 and 118 are obstructed by toroids 114a and 114b, respectively, as shown in
From
It is of course to be appreciated that the components of the various embodiments discussed herein could be interchanged with corresponding or similar components in other discussed variants, or with any other equivalents or substitutes, and that such modifications are within the intended scope of the current disclosure. For example, first and second wedges 150 and 152 could be replaced by any of the other assemblies discussed herein, or the sealing area 144 could be filled with, or surrounded by, stainless steel mesh, steel wool, elastomers, filler material, etc. Furthermore, it is to be appreciated that any of the assemblies described herein could be used as both a backup and a sealing element, or as a backup for a separate sealing element.
It is also to be understood that while the above-described embodiments refer to expanding the toroids to obstruct radially outwardly located gaps, these dimensions could be reversed or inverted. That is, for example, instead of a conical wedge, the setting member could take the form of a funnel arranged radially outwardly from the toroids, for compressing the toroids to obstruct a radially inwardly located gap. For example, the toroids could be made from a partially compressible material, or could take the form of a pre-stretched or plastically deformed garter spring. It is to be noted that illustrations for such inverted embodiments would virtually identically resemble the Figures disclosed herein, as the cross- or quarter-sections would be essentially mirror images of each other. Thus, generally according to the embodiments of the current invention, increasingly engaging a toroid with a suitable setting member (regardless of expansion or compression) results in the setting member altering the toroid (e.g., enlarging or compressing) in order to change a boundary dimension (e.g., a maximum outer dimension, a minimum inner dimension, etc.) of an assembly by extending the boundary dimension of the assembly radially toward the gap to be obstructed.
While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
