A typical sealing assembly (e.g., packer, bridge plug, etc.) generally has one or more sealing elements or “rubbers” that are employed to provide a fluid-tight seal radially between a mandrel of the sealing assembly and the casing or wellbore into which the sealing assembly is disposed. Such a sealing assembly is commonly conveyed into a subterranean wellbore suspended from tubing extending to the earth's surface.
To prevent damage to the sealing elements while the sealing assembly is being conveyed into the wellbore, the sealing elements are carried on the mandrel in a relaxed or uncompressed state in which they are radially inwardly spaced apart from the casing. When the sealing assembly is set, the sealing elements radially expand (e.g., both radially inward and radially outward), thereby sealing against the mandrel and the casing and/or wellbore. In certain embodiments, the sealing elements are axially compressed between element retainers straddling the sealing elements on the seal assembly, which in turn radially expand the sealing elements. In other embodiments, one or more swellable sealing elements are axially positioned between the element retainers, the swellable sealing elements configured to radially expand when subjected to one or more different activation fluids.
The seal assembly often includes one or more slip rings, which grip the casing and prevent movement of the seal assembly axially within the casing after the sealing elements have been set. Thus, if weight or fluid pressure is applied to the seal assembly, the slip rings resist the axial forces on the seal assembly produced thereby, and prevent axial displacement of the seal assembly relative to the casing and/or wellbore.
Reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:
In the drawings and descriptions that follow, like parts are typically marked throughout the specification and drawings with the same reference numerals, respectively. The drawn figures are not necessarily to scale. Certain features of the disclosure may be shown exaggerated in scale or in somewhat schematic form and some details of certain elements may not be shown in the interest of clarity and conciseness. The present disclosure may be implemented in embodiments of different forms.
Specific embodiments are described in detail and are shown in the drawings, with the understanding that the present disclosure is to be considered an exemplification of the principles of the disclosure, and is not intended to limit the disclosure to that illustrated and described herein. It is to be fully recognized that the different teachings of the embodiments discussed herein may be employed separately or in any suitable combination to produce desired results.
Unless otherwise specified, use of the terms “connect,” “engage,” “couple,” “attach,” or any other like term describing an interaction between elements is not meant to limit the interaction to direct interaction between the elements and may also include indirect interaction between the elements described. Unless otherwise specified, use of the terms “up,” “upper,” “upward,” “uphole,” “upstream,” or other like terms shall be construed as generally toward the surface of the ground; likewise, use of the terms “down,” “lower,” “downward,” “downhole,” or other like terms shall be construed as generally toward the bottom, terminal end of a well, regardless of the wellbore orientation. Use of any one or more of the foregoing terms shall not be construed as denoting positions along a perfectly vertical axis. Unless otherwise specified, use of the term “subterranean formation” shall be construed as encompassing both areas below exposed earth and areas below earth covered by water such as ocean or fresh water.
The present disclosure has acknowledged that typical c-ring slip rings, which often contain a single axial slot therein (e.g., aligned with Figs a centerline (CL) of the slip ring), do not provide 360-degree contact between the packer and the surrounding tubular when in the radially enlarged state. Specifically, as the axial slot widens when the slip ring moves from the radially reduced state to the radially enlarged state, an exposed region exists where there is no contact between the packer and the surrounding tubular. The present disclosure has further acknowledged that the exposed region may cause the packer to cantilever within the surrounding tubular, as well as creates misalignment between related upper and lower c-ring slip rings, which are both undesirable.
Based upon the foregoing acknowledgments, the present disclosure has recognized that the undesirable cantilever effect may be reduced, if not eliminated, if there is 360-degree contact between the packer and the surrounding tubular when the slip ring is in the radially enlarged state. The present disclosure has further recognized that the 360-degree contact may be achieved with a slip ring employing a slot that is misaligned with the centerline (CL) of the slip ring. For example, the present disclosure has recognized that the 360-degree contact may be achieved using a slip ring employing a slot extending between a first end and a second opposing end of a ring member, wherein a first portion of the slot located at the first end and a second portion of the slot located at the second opposing end are radially offset from one another by at least 15-degrees. The slot may take on many different shapes while achieving the discussed radially offset, including both non-linear and linear slots. In at least one embodiment, the slot is a non-linear slot, such as a Z-shaped slot, an S-shaped slot, a spiral shaped slot, or a helical shaped slot, among others. In yet another embodiment, the slot is a linear slot, such as a linear slot extended from the first end to the second opposing end at an angle.
Therefore, a slip ring designed, manufactured, and used according to the present disclosure will allow for 360-degree contact between the packer and the surrounding tubular, even when in the radially enlarged state, without the need for a full barrel style type external slip ring. Full barrel style type external slip rings are expensive to manufacture. Moreover, a slip ring according to the disclosure can be manufactured generally using the same processes used to manufacture typical c-ring slip rings (with the exception of the process used to form the slot), which is much less expensive. Accordingly, the slip ring of the present disclosure could be used as a direct replacement for existing c-ring slip rings with a slot of all sizes and weight ranges, and thus may be readily used in certain low-cost commodity packers.
An example well sealing tool 150 is coupled with a tubing string 160 that extends from a wellhead 170 into the wellbore 110. The tubing string 160 can be a coiled tubing and/or a string of joint tubing coupled end to end. For example, the tubing string 160 may be a working string, an injection string, and/or a production string. The sealing tool 150 can include a bridge plug, frac plug, packer and/or other sealing tool, having a seal assembly 155 for sealing against the wellbore 110 wall (e.g., the casing 140, a liner and/or the bare rock in an open hole context). The seal assembly 155 can isolate an interval of the wellbore 110 above the seal assembly 155 from an interval of the wellbore 110 below the seal assembly 155, for example, so that a pressure differential can exist between the intervals.
In accordance with the disclosure, the seal assembly 155 may comprise a slip ring including a ring member having a first end, a second opposing end, a width (w), and a wall thickness (t). The slip ring, in at least one embodiment, further includes a slot located entirely through the wall thickness (t) and extending between the first end and the second opposing end, the slot configured to allow the ring member to move between a radially reduced state and a radially enlarged state. The slip ring, in yet another embodiment, is configured such that a first portion of the slot located at the first end and a second portion of the slot located at the second opposing end are radially offset from one another by at least 15-degrees.
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The slip ring 200, in the illustrated embodiment, includes a first end 220 and a second opposing end 225. In at least one embodiment, the first end 220 is a first uphole end, and the second opposing end 225 is a second downhole end. Nevertheless, the opposite could be true, and in fact certain embodiments employ two slip rings 200 that would be oppositely arranged. In the embodiment of
In the embodiment of
The slip ring 200 of
The slot 250 may take on many different shapes while achieving the aforementioned radial offset. In at least one embodiment, such as shown, the slot 250 is a non-linear slot. However, in other embodiments, the slot 250 is a liner slot. In the embodiment of
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The sealing tool 700, in the illustrated embodiment of
The sealing assembly 720, may additionally include one or more sealing elements 750 positioned about the mandrel, the one or more sealing elements 750 operable to move between a radially relaxed state and a radially expanded state. The one or more sealing elements 750, in the illustrated embodiment, are positioned between the first and second slip rings 730, 735. In at least one embodiment, the one or more sealing elements 750 are elastomeric sealing elements. In at least one other embodiment, the one or more sealing elements 750 are one or more swellable sealing elements.
The sealing assembly 720, in the illustrated embodiment, additionally includes one or more associated wedges 760. The one or more associated wedges 760, in the illustrated embodiment, include one or more associated angled surfaces that are operable to engage with the inside diameter (di) of the first and second slip rings 730, 735. Accordingly, the one or more associated wedges 760 may be used to move the first and second slip rings 730, 735 between the radially reduced state (e.g., as shown in
The seal assembly 720, in one or more embodiments, additionally includes a piston structure 770 for axially moving the first and second slip rings 730, 735, one or more sealing elements 750, and one or more associated wedges 760 relative to one another. Accordingly, the piston structure 770 may be used to move the first and second slip rings 730, 735 between the radially reduced state (e.g., as shown in
Aspects disclosed herein include:
A. A slip ring for use with a sealing assembly, the slip ring including: 1) a ring member having a first end, a second opposing end, a width (w), and a wall thickness (t); and 2) a slot located entirely through the wall thickness (t) and extending between the first end and the second opposing end, the slot configured to allow the ring member to move between a radially reduced state and a radially enlarged state, and further wherein a first portion of the slot located at the first end and a second portion of the slot located at the second opposing end are radially offset from one another by at least 15-degrees.
B. A sealing tool, the sealing tool including: 1) a mandrel; and 2) a sealing assembly positioned about the mandrel, the sealing assembly having a slip ring including: a) a ring member having a first end, a second opposing end, a width (w), and a wall thickness (t); and b) a slot located entirely through the wall thickness (t) and extending between the first end and the second opposing end, the slot configured to allow the ring member to move between a radially reduced state and a radially enlarged state, and further wherein a first portion of the slot located at the first end and a second portion of the slot located at the second opposing end are radially offset from one another by at least 15-degrees.
C. A method for sealing an annulus within a wellbore, the method including: 1) providing a sealing tool within a wellbore, the sealing tool including: a) a mandrel; and b) a sealing assembly positioned about the mandrel, the sealing assembly having a slip ring including: i) a ring member having a first end, a second opposing end, a width (w), and a wall thickness (t); and ii) a slot located entirely through the wall thickness (t) and extending between the first end and the second opposing end, the slot configured to allow the ring member to move between a radially reduced state and a radially enlarged state, and further wherein a first portion of the slot located at the first end and a second portion of the slot located at the second opposing end are radially offset from one another by at least 15-degrees; and 2) setting the slip ring by moving the expandable metal ring member from the radially reduced state to the radially enlarged state engaged with a tubular in the wellbore.
Aspects A, B, and C may have one or more of the following additional elements in combination: Element 1: wherein the first portion of the slot located at the first end and the second portion of the slot located at the second opposing end are radially offset from one another by at least 360-degrees. Element 2: wherein the first portion of the slot located at the first end and the second portion of the slot located at the second opposing end are radially offset from one another by at least 180-degrees. Element 3: wherein the first portion of the slot located at the first end and the second portion of the slot located at the second opposing end are radially offset from one another by at least 90-degrees. Element 4: wherein the slot is a non-linear slot. Element 5: wherein the slot is a Z-shaped slot. Element 6: wherein the slot is an S-shaped slot. Element 7: wherein the slot is a linear slot. Element 8: further including one or more reduced thickness notched located in the ring member, the one or more reduced thickness notches configured to allow the ring member to flex between the radially reduced state and the radially enlarged state. Element 9: further including a plurality of teeth extending from the ring member, the plurality of teeth configured to grip a tubular located outside of the ring member when the ring member is in the radially enlarged state. Element 10: wherein the sealing assembly further includes one or more sealing elements positioned about the mandrel, the one or more sealing elements operable to move between a radially relaxed state and a radially expanded state. Element 11: wherein the one or more sealing elements are one or more elastomeric sealing elements. Element 12: wherein the sealing assembly further includes one or more wedges positioned about the mandrel, the one or more wedges operable to move the ring member between the radially reduced state and the radially enlarged state. Element 13: further including one or more reduced thickness notched located in the ring member, the one or more reduced thickness notches configured to allow the ring member to flex between the radially reduced state and the radially enlarged state, and a plurality of teeth extending from the ring member, the plurality of teeth configured to grip a tubular located outside of the ring member when the ring member is in the radially enlarged state. Element 14: wherein the slip ring in the radially enlarged state has 360-degree contact with the tubular.
Those skilled in the art to which this application relates will appreciate that other and further additions, deletions, substitutions, and modifications may be made to the described embodiments.