The invention relates to what is generally known as a completion, workover, stimulation, or intervention of subterranean wells. Specifically, this invention relates to flow control devices, plugs and packers, and installing/removing flow control devices, plugs and packers from a subterranean wellbore.
Packers, plugs, and flow control devices such as landing nipples are used to support well stimulation, well completion, well workover, and well intervention operations. In many horizontal or near horizontal downhole applications (e.g., shale fracking) a plug or other device must be placed in the horizontal wellbore section. In these exemplary applications, a plug performs two actions: (1) grip, and (2) seal. One way of performing these actions is with a system using slips and elastomers that are pushed towards the wellbore using a cone and compression system. These systems may not be reliable or are limited because of the possibility of the elastomers extruding during use and losing their ability to seal or even swabbing off the device during the installation.
Another way of performing one or both of these actions is stretching a solid metal tube with a cone or other device. In this context, stretching means the expanding of a solid tube (i.e., a tube that is not slotted) such that both the outer perimeter and inner perimeter of the solid tube are enlarged. These systems may not be reliable or are limited because a solid metal tube can only be stretched a certain amount before it no longer has the mechanical integrity to perform its function. This technology is generally known to the industry as solid expandable.
Accordingly, there is a need for an apparatus that seals and/or grips against the wellbore wall without requiring any materials to be stretched or losing its ability to seal.
Embodiments of the invention allow for an apparatus, referred to as a roll-out apparatus, to be installed into a well tubular or open hole at a setting location. In one embodiment the roll-out apparatus includes a load ring that is rolled-out via an energizing ring. In the rolled-out position, the load ring may grip, seal, or both grip and seal to an inner surface of a well tubular or open hole creating a ledge in the wellbore. The ledge created by the roll-out apparatus may be used as seat for a ball or dart to create a diversion device, or to be used as a ledge to support the installation of downhole tools such as a pressure gauge.
Embodiments of the roll-out apparatus include a load ring having a generally tubular shape with at least one slot extending from the front face of the ring to the back face of the ring. The slot enables the load ring to roll-out or enlarge by bending, when energized on an inner surface of the load ring. The slot in the load ring follows a circuitous path and includes a first inner surface and a second inner surface that are configured to contact one another when the load ring is energized or enlarged. The load ring is further configured to contact an inner surface of the subterranean well at the setting location. This contact will result in a either a grip, a seal, or both a grip and seal. This interaction secures the roll-out apparatus in the subterranean well at the setting location.
To allow installation, the roll-out apparatus is typically run on a setting tool system, where the load ring and energizing ring is connected to the setting tool via a core, deployment device or system. The roll-out apparatus is first positioned on the deployment device. The system is then deployed into a wellbore and after the setting location is reached, the setting tool is activated causing the outer surface of the energizing ring to contact the inner surface of the load ring to enlarge the outer circumference of the load ring in a radial direction. This causes the load ring to contact an inside surface of the subterranean well at the setting location.
Those skilled in the art will appreciate that seal or sealing means that if a ball, dart, or plug is attached to the roll-out apparatus, and pressure is applied on top of the roll-out apparatus with the ball, plug, or dart, the leak rate is sufficiently low to allow fluids to be diverted into the formation above the roll-out apparatus. In other words, a 100% seal may be accomplished, but is not required to provide full functionality.
An advantage of the proposed method and apparatus is that it is a tubular ring that is enlarged by bending, to provide gripping and/or sealing to the inner surface of the subterranean well. The tubular ring includes a slot that enables the outer circumference of the load ring to enlarge in a radial direction thereby causing the outer surface of the load ring to contact an inner surface of the subterranean well at the setting location. The slot follows a circuitous path and includes a first inner surface and a second inner surface that are configured to contact one another when the load ring is energized or enlarged. Although the roll-out apparatus does not require additional parts to achieve its functionality, items such as a core, dart, plug, or ball may be incorporated with or after the installation, thereby interacting with the roll-out apparatus, creating additional functionality and possibly enhancing its grip and/or seal with the tubular wall. Thus, the roll-out apparatus may have profiles, shoulders or contours to interact with another device such as but not limited to: a ball, a dart, or a seal assembly.
The roll-out apparatus includes a load ring that may have a textured outer surface modified to enhance gripping and/or sealing to the wellbore walls. Such enhancements include, but are not limited to, particles such as silicon carbide (SiC) attached to the outer surface, which are harder than the material of the wellbore wall and/or the roll-out apparatus. Attachment of these particles may increase the friction force between the load ring and the subterranean well and can be accomplished using an epoxy or resin or other methods including, but not limited to: (1) sintering; (2) profiles machined or attached to the outer surface (the profiles may be treated to increase their hardness); and (3) sealing systems such as elastomers or thermo plastics bonded to the roll-out apparatus. The outer surface of the load ring may include at least one shoulder extending to or above the textured surface configured to engage the inner surface of the subterranean well. Those skilled in the art will appreciate that many different gripping and sealing systems or components exist and that these can be used on their own or in combination with each other. Even though the load ring's main purpose is to seal and grip, those skilled in the art will appreciate that the load ring may also be used for either gripping or sealing.
The roll-out apparatus and its other components can be made from a variety of materials, including but not limited to: alloy steel, stainless steel, duplex steel, elastomers, thermo plastics, composites, degradable materials, dissolvable material, aluminum, or combinations thereof. As discussed, another device or system such as a ball or dart can be installed to interact with the roll-out apparatus to collectively form a plug and/or to further enhance conformance of the roll-out with the inner circumference of the wellbore and/or enhance the gripping/sealing capabilities or other properties, performance, or features. These other devices or systems may be installed during, with, or after the installation of the roll-out apparatus. Some of these devices or systems can be used to enhance the ease of installation of the roll-out apparatus.
Other enhancements to the roll-out apparatus may include but are not limited to a load ring assembly that includes two or more rings interlocked together. Each ring includes a slot extending from the front face of the ring to the back face of the ring. The circuitous path of the load ring assembly is formed by orienting the slot of one ring at a different angular orientation to the adjacent ring so that the slots of each ring do not overlap when the load ring is enlarged by the energizing ring.
The specification provides one embodiment of an apparatus configured to be deployed in a subterranean well at a setting location having a load ring and an energizing ring. The load ring includes an outer surface having an outer circumference, an inner surface, a central axis, and a wall having a wall thickness. The wall includes at least one slot extending through the entire wall thickness, and the slot follows a circuitous path from a front face of the load ring to a back face of the load ring. The slot has a first inner surface and a second inner surface, and a portion of the first inner surface and a portion of the second inner surface are configured to contact one another when the outer circumference of the load ring is enlarged;
The energizing ring in this embodiment includes an outer surface, an inner surface, and a central axis. The outer surface of the energizing ring is configured to contact the inner surface of the load ring and to enlarge the outer circumference of the load ring in a radial direction. This causes the outer surface of the load ring to seal to an inner surface of the subterranean well at the setting location. Those skilled in the art will appreciate that in some cases and due to the high loads that the roll-out apparatus is subjected to, the apparatus may move or slip relative to the setting location. This movement or slipping is expected and normally not more than a few inches.
In this embodiment, the circuitous path of the slot may include a first portion that runs parallel to the central axis at the front face, a second portion that runs parallel to the central axis at the back face, and a third portion that runs perpendicular to the central axis at one or more locations between the front face and the back face. The circuitous path may also include at least one portion that is oriented at an angle to the central axis. In addition, the outer surface of the load ring may include a textured surface configured to engage and grip the inner surface of the subterranean well. The textured surface may also include a particulate configured to increase the friction force between the load ring and the subterranean well. In another embodiment, the outer surface of the load ring may include at least one shoulder extending to or above the textured surface to engage and grip the inner surface of the subterranean well.
In this embodiment, the inner surface of the load ring may include a convex surface relative to the central axis of the load ring, and the outer surface of the energizing ring may include a tapered surface relative to the central axis of the energizing ring. In another embodiment, the inner surface of the load ring may include a tapered surface relative to the central axis of the load ring, and the outer surface of the energizing ring may include a convex surface relative to the central axis of the energizing ring. In addition, the load ring, the energizing ring, or both the load ring and energizing ring may be made of a material that galvanically corrodes in a subterranean well. Similarly, the load ring, the energizing ring, or both the load ring and energizing ring may be made of a material that disintegrates or dissolves as a result of an interaction with a fluid in a subterranean well. The load ring, the energizing ring, or both the load ring and energizing ring may also include a composite material.
The load ring may be an assembly of two or more rings interlocked together. Each load ring may have a slot extending through the entire wall thickness from the front face of the ring to the back face of the ring. The circuitous path of the load ring may be formed by orienting the slot of at least one ring at a different angular orientation to the adjacent ring so that the slots of each ring do not overlap when the load ring is enlarged by the energizing ring.
According to another embodiment, the specification provides a method of installing an apparatus in a subterranean well. The method includes positioning a load ring and an energizing ring on a deployment device. The load ring includes an outer surface having an outer circumference, an inner surface, a central axis, and a wall having a wall thickness. The wall of the load ring includes at least one slot extending through the entire wall thickness, and the slot follows a circuitous path from the front face of the load ring to the back face of the load ring. The energizing ring includes an outer surface, an inner surface, and a central axis. The deployment device may include a pivot point configured to reduce the friction force between the deployment device and the inner surface of the subterranean well.
The method further includes inserting the deployment device and the ring into the subterranean well. The ring may be positioned on the deployment device in a first orientation that allows the ring and the deployment device to traverse the subterranean well. The method further includes delivering the deployment device, the load ring, and the energizing ring to a setting location in the subterranean well. Once at the setting location, the method includes activating the deployment device to move the outer surface of the energizing ring to contact the inner surface of the load ring to enlarge the outer circumference of the load ring in a radial direction. This causes the outer surface of the load ring to seal to an inner surface of the subterranean well at the setting location.
In this method, the circuitous path of the slot may include a first portion that runs parallel to the central axis at the front face, a second portion that runs parallel to the central axis at the back face, and a third portion that runs perpendicular to the central axis at one or more locations between the front face and the back face. The circuitous path may also include at least one portion that is oriented at an angle to the central axis. In addition, the outer surface of the load ring may include a textured surface configured to engage and grip the inner surface of the subterranean well. The textured surface may also include a particulate configured to increase the friction force between the load ring and the subterranean well. Alternatively, the outer surface of the load ring may include at least one shoulder extending to or above the textured surface to engage and grip the inner surface of the subterranean well.
In this method, the inner surface of the load ring may include a convex surface relative to the central axis of the load ring, and the outer surface of the energizing ring may include a tapered surface relative to the central axis of the energizing ring. Alternatively, the inner surface of the load ring may include a tapered surface relative to the central axis of the load ring, and the outer surface of the energizing ring may include a convex surface relative to the central axis of the energizing ring. In addition, the load ring, the energizing ring, or both the load ring and energizing ring may be made of a material that galvanically corrodes in a subterranean well. Similarly, the load ring, the energizing ring, or both the load ring and energizing ring may be made of a material that disintegrates or dissolves as a result of an interaction with a fluid in a subterranean well. The load ring, the energizing ring, or both the load ring and energizing ring may also include a composite material.
The load ring in this method may be an assembly of two or more rings interlocked together. Each load ring may have a slot extending through the entire wall thickness from the front face of the ring to the back face of the ring. The circuitous path of the load ring may be formed by orienting the slot of at least one ring at a different angular orientation to the adjacent ring so that the slots of each ring do not overlap when the load ring is enlarged by the energizing ring.
According to another embodiment, the specification provides a subterranean well assembly. The subterranean well has an inner surface at a setting location, which may be defined by casing. The subterranean well also includes a load ring and an energizing ring. The load ring includes an outer surface having an outer circumference, an inner surface, a central axis, and a wall having a wall thickness. The wall includes at least one slot extending through the entire wall thickness, and the slot follows a circuitous path from the front face of the load ring to the back face of the load ring. The slot has a first inner surface and a second inner surface, and a portion of the first inner surface and a portion of the second inner surface are configured to contact one another when the outer circumference of the load ring is enlarged.
The energizing ring includes an outer surface, an inner surface, and a central axis. The outer surface of the energizing ring is configured to contact the inner surface of the load ring and to enlarge the outer circumference of the load ring in a radial direction. This causes the outer surface of the load ring to seal to an inner surface of the subterranean well at the setting location.
In this embodiment, the circuitous path of the slot may include a first portion that runs parallel to the central axis at the front face, a second portion that runs parallel to the central axis at the back face, and a third portion that runs perpendicular to the central axis at one or more locations between the front face and the back face. The circuitous path may also include at least one portion that is oriented at an angle to the central axis. In addition, the outer surface of the load ring may include a textured surface configured to engage and grip the inner surface of the subterranean well. The textured surface may also include a particulate configured to increase the friction force between the load ring and the subterranean well. In another embodiment, the outer surface of the load ring may include at least one shoulder extending to or above the textured surface to engage and grip the inner surface of the subterranean well.
In this embodiment, the inner surface of the load ring may include a convex surface relative to the central axis of the load ring, and the outer surface of the energizing ring may include a tapered surface relative to the central axis of the energizing ring. In another embodiment, the inner surface of the load ring may include a tapered surface relative to the central axis of the load ring, and the outer surface of the energizing ring may include a convex surface relative to the central axis of the energizing ring. In addition, the load ring, the energizing ring, or both the load ring and energizing ring may be made of a material that galvanically corrodes in a subterranean well. Similarly, the load ring, the energizing ring, or both the load ring and energizing ring may be made of a material that disintegrates or dissolves as a result of an interaction with a fluid in a subterranean well. The load ring, the energizing ring, or both the load ring and energizing ring may also include a composite material.
The load ring may be an assembly of two or more rings interlocked together. Each load ring may have a slot extending through the entire wall thickness from a front face of the ring to a back face of the ring. The circuitous path of the load ring may be formed by orienting the slot of at least one ring at a different angular orientation to the adjacent ring so that the slots of each ring do not overlap when the load ring is enlarged by the energizing ring.
The drawings accompanying and forming part of this specification are included to depict certain aspects of embodiments of the invention. A clearer impression of embodiments of the invention, and of the components and operation of systems provided with embodiments of the invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings, wherein identical reference numerals designate the same components. Note that the features illustrated in the drawings are not necessarily drawn to scale.
This disclosure and the various features and advantageous details thereof are explained more fully with reference to the non-limiting embodiments that are illustrated in the accompanying drawings and detailed in the following description. Descriptions of well-known starting materials, processing techniques, components and equipment are omitted so as not to unnecessarily obscure the disclosure in detail. Skilled artisans should understand, however, that the detailed description and the specific examples, while disclosing preferred embodiments, are given by way of illustration only and not by way of limitation. Various substitutions, modifications, additions or rearrangements within the scope of the underlying inventive concept(s) will become apparent to those skilled in the art after reading this disclosure.
Setting location 18 may be at any location in subterranean well 8, and roll-out apparatus 16 may be configured for the setting location based on the inner diameter or inner circumference of the subterranean well. One advantage of the invention is that roll-out apparatus 16 may operate in several types of wellbores. For example, those skilled in the art will also appreciate that roll-out apparatus 16 may also be set in sections of a wellbore that do not contain any tubulars. These sections are generally known to the industry as open hole. In this instance, roll-out apparatus 16 will interact with the exposed geological formation.
In one embodiment, slot 36 includes first portion 40 that runs parallel to central axis 24 at front face 32, second portion 42 that runs parallel to the central axis 24 at back face 34, and third portion 44 that runs perpendicular to central axis 24 at one or more locations between front face 32 and back face 34. Slot 36 is illustrated in FIGS. 2-5 as having a rectangular shape, but the invention is not limited to this particular slot geometry and may include any functional shape, and by no means is limited to a rectangular shape, either in part or in whole. For example,
Furthermore,
As mentioned, load ring 22 includes an inner surface 30 that may include first portion 58, second portion 60, and third portion 62. First portion 58 may include a chamfer and second portion 60 may include a flat portion 61, which may facilitate positioning and maintaining load ring 22 on a deployment device. As will be discussed in more detail below, third portion 62 is the portion of inner surface 30 that is contacted by the energizing ring to enlarge circumference 28 in a radial direction thereby causing the outer surface of the load ring to contact an inner surface of the subterranean well at the setting location. Third portion 62 of inner surface 30 may include a non-linear shape relative to the central axis 24. For example, third portion 62 may include a convex surface relative to central axis 24. In an alternative embodiment, third portion 62 may include a tapered surface relative to central axis 24.
In these exemplary embodiments, wall thickness 25 decreases in third portion 62 when moving along central axis 24 from front face 32 to back face 34. A person or ordinary skill in the art would understand that the invention is not limited to a particular wall thickness. Similarly, a person or ordinary skill in the art would understand that third portion 62 is not limited to a particular shape and may include a combination of linear and non-linear shapes, or any shape that provides a contact surface or point for the energizing ring.
As illustrated in
In addition, the illustrated embodiment includes a ramp shape for portion 52. A person of ordinary skill in the art would understand that contact between portion 50 and 52 may be accomplished using a number of other shapes or configurations, and is not limited to the illustrated embodiment. For example, slot 36 may be created by a shearing press resulting in a completely flat first inner surface 46 and second inner surface 48, where the inner and outer surface maintain contact with each other during and after enlarging of the circumference.
Outer surface 68 of energizing ring 66 may include a first portion 74 and a second portion 76. First portion 74 may be a flat surface, and second portion 76 of outer surface 68 may include a tapered surface relative to central axis 72. Tapered surface 76 is configured to contact third portion 62 of inner surface 30 of load ring 22. In an alternative embodiment, second portion 76 may include a non-liner surface relative to central axis 72. For example, second portion 76 may include a convex surface relative to central axis 72. A person or ordinary skill in the art would understand that second portion 76 is not limited to a particular shape and may include a combination of linear and non-linear shapes, or any shape that provides a contact surface to engage inner surface 30 of load ring 22.
Energizing ring 66 may also include slot 78 extending through wall thickness 80 of energizing ring 66. As illustrated, slot 78 extends from front face 82 to back face 84 of energizing ring 66. Slot 78 may be parallel with central axis 72, or it may be oriented at angle 85 from central axis 72. Moreover, single slot 78 is only one exemplary embodiment, and other embodiments of the invention may include one or more slots that do not extend the full length of outer surface 68, but instead extend only a portion of the length of outer surface 68.
In
The further energizing ring 66 is advanced into load ring 22, the larger outer circumference 28 of load ring 22 becomes, as indicated by an increase in the size of gap 86. As illustrated and discussed above, outer circumference 28 of load ring 22 is enlarged by bending or is rolled open. This makes it easier to energize the load ring, which enhances the gripping and sealing of the load ring. In this scenario, there is no longer gap 94 and the energized load ring 22 is engaged at setting location 18.
Each ring 98, 100, 102 in load ring assembly 96 may be interlocked together using groove configuration 114. Once the rings are interlocked, the groove configuration prevents detachment while still allowing for relative rotating and sliding such that the groove maintains a seal between the rings. To enhance sealing and/or sliding the groove may contain a grease or sealing compound. A person or ordinary skill in the art would understand that there are a number of ways to interlock ring 98, 100, and 102, and the invention is not limited to the illustrated embodiment. Load ring assembly 96 includes an inner surface 30 that is contacted by the energizing ring to enlarge out circumference 28 in a radial direction thereby causing the outer surface of load ring assembly 96 to contact an inner surface of the subterranean well at the setting location. As with load ring 22, inner surface 30 may include a non-linear shape relative to the central axis 24. For example, inner surface 30 may include a convex surface relative to central axis 24.
In an alternative embodiment, inner surface 30 may include a tapered surface relative to central axis 24. In these exemplary embodiments, wall thickness 106 decreases when moving along central axis 24 from front face 108 to back face 110. A person or ordinary skill in the art would understand that the invention is not limited to a particular wall thickness. Similarly, a person or ordinary skill in the art would understand that inner surface 30 is not limited to a particular shape and may include a combination of linear and non-linear shapes, or any shape that provides a contact surface or point for the energizing ring.
The illustrated deployment device 116 is attached to a setting tool 118 and includes a setting sleeve 120, a release mechanism 122 and a pivot point 124. The shown deployment device is relatively common for the field of use, except for the addition of several pivot points. When one or more pivot points are touching the tubular wall, the energizing ring 66 and gauge ring 126 will be lifted by the weight of the setting tool 118 and/or other uphole connected devices such that the frictional contact of the energizing ring or gauge ring rubbing against the tubular wall is reduced.
Although the invention has been described with respect to specific embodiments thereof, these embodiments are merely illustrative, and not restrictive of the invention. Rather, the description is intended to describe illustrative embodiments, features and functions in order to provide a person of ordinary skill in the art context to understand the invention without limiting the invention to any particularly described embodiment, feature or function. While specific embodiments of, and examples for, the invention are described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the invention, as those skilled in the relevant art will recognize and appreciate. As indicated, these modifications may be made to the invention in light of the foregoing description of illustrated embodiments of the invention and are to be included within the spirit and scope of the invention. Thus, while the invention has been described herein with reference to particular embodiments thereof, a latitude of modification, various changes and substitutions are intended in the foregoing disclosures, and it will be appreciated that in some instances some features of embodiments of the invention will be employed without a corresponding use of other features without departing from the scope and spirit of the invention as set forth. Therefore, many modifications may be made to adapt a particular situation or material to the essential scope and spirit of the invention.
Reference throughout this specification to “one embodiment”, “an embodiment”, or “a specific embodiment” or similar terminology means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment and may not necessarily be present in all embodiments. Thus, respective appearances of the phrases “in one embodiment”, “in an embodiment”, or “in a specific embodiment” or similar terminology in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics of any particular embodiment may be combined in any suitable manner with one or more other embodiments. It is to be understood that other variations and modifications of the embodiments described and illustrated herein are possible in light of the teachings herein and are to be considered as part of the spirit and scope of the invention.
In the description herein, numerous specific details are provided, such as examples of components and/or methods, to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that an embodiment may be able to be practiced without one or more of the specific details, or with other apparatus, systems, assemblies, methods, components, materials, parts, and/or the like. In other instances, well-known structures, components, systems, materials, or operations are not specifically shown or described in detail to avoid obscuring aspects of embodiments of the invention. While the invention may be illustrated by using a particular embodiment, this is not and does not limit the invention to any particular embodiment and a person of ordinary skill in the art will recognize that additional embodiments are readily understandable and are a part of this invention.
As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having,” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, product, article, or apparatus that comprises a list of elements is not necessarily limited only those elements but may include other elements not expressly listed or inherent to such process, product, article, or apparatus.
Furthermore, the term “or” as used herein is generally intended to mean “and/or” unless otherwise indicated. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present). As used herein, a term preceded by “a” or “an” (and “the” when antecedent basis is “a” or “an”) includes both singular and plural of such term, unless clearly indicated otherwise (i.e., that the reference “a” or “an” clearly indicates only the singular or only the plural). Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
This patent application claims priority to U.S. patent application Ser. No. 17/207,528, filed Mar. 19, 2021, which claims priority to U.S. Provisional App. No. 62/994,005 filed 2020 Mar. 24 and to U.S. Provisional App. No. 63/110,989 filed 2020 Nov. 7, all of which are hereby incorporated herein by reference.
Number | Name | Date | Kind |
---|---|---|---|
4333661 | Merrell | Jun 1982 | A |
4745972 | Bell | May 1988 | A |
6793022 | Vick | Sep 2004 | B2 |
8579024 | Malland et al. | Nov 2013 | B2 |
10119359 | Frazier | Nov 2018 | B2 |
20090126925 | Guest | May 2009 | A1 |
20140196889 | Oberg | Jul 2014 | A1 |
20150285026 | Frazier | Oct 2015 | A1 |
20170022781 | Martin et al. | Jan 2017 | A1 |
20180016864 | Parekh | Jan 2018 | A1 |
20180038193 | Walton | Feb 2018 | A1 |
20180266205 | Martin et al. | Sep 2018 | A1 |
20190368304 | Deng | Dec 2019 | A1 |
20190383108 | Massey | Dec 2019 | A1 |
20200063521 | Godfrey | Feb 2020 | A1 |
Number | Date | Country |
---|---|---|
2253870 | Sep 1992 | GB |
WO2012045168 | Apr 2012 | WO |
Entry |
---|
PCT International Search Report for PCT/US2021/023757. |
Written Opinion of the International Searching Authority for PCT/US2021/023757. |
Number | Date | Country | |
---|---|---|---|
20220316292 A1 | Oct 2022 | US |
Number | Date | Country | |
---|---|---|---|
63110989 | Nov 2020 | US | |
62994005 | Mar 2020 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 17207528 | Mar 2021 | US |
Child | 17849046 | US |