Patent Application
20240360736
In the process of drilling and producing oil and gas wells, certain zones within the wellbore are isolated or sealed from surrounding zones or from the surface of the wellbore. After drilling a wellbore, a casing is typically set along the outer surface of the wellbore. Bridge plugs, packers, and/or other sealing devices are then set within the casing to isolate defined zones within the wellbore. For example, the isolated zone may be created between 5,000 and 10,000 feet downstream from the surface. The sealing devices will fluidly seal the isolated zone from other zones such that only the isolated zone will be in fluid communication with the surface of the wellbore. In other words, the sealing devices prevent fluid communication between all other zones and the surface of the wellbore. The casing in the isolated zone is perforated to allow fluid communication between the subterranean formation and the isolated zone of the wellbore and ultimately the surface of the wellbore.
Rupture discs are sometimes used in sealing devices for fluid isolation of wellbore zones. Conventional rupture discs include smooth arched surfaces, which allow for a greater pressure rating on one side of the rupture disc than the other side. When operations are completed in the isolated zone, the rupture disc may be broken to allow fluid communication between other zones and the surface of the wellbore. The breaking of the rupture disc creates fragments of unpredictable size and shape. Often, the disc fragments are large and create problems, such as blocking openings or presenting difficulty in removing the disc fragments from the wellbore.
Disclosed herein is a sealing system including a frangible rupture disc and a plug selectively retained by a sleeve. The plug, which may be dissolvable or non-dissolvable, is configured to be selectively released from the sleeve, which causes the rupture disc to fracture into fragments. The plug is also configured to clear the fragments of the rupture disc from the rupture disc housing. The sealing system may be used in underbalanced wells.
With reference to
Referring now to
In addition to the inner diameter configuration of rings 38 and 42 and trim spacer 40, one or more of the rings in sleeve 26 may include a retainer, and at least one retainer may form a seat. For example, upstream ring 38 and downstream ring 42 may each include a retainer, and the retainer of downstream ring 42 may form a seat for plug 28, such as a ball seat for a dissolvable or non-dissolvable ball. In the illustrated embodiment, a retainer of upstream ring 38 includes tapered shoulder 44, and a retainer of downstream ring 42 includes tapered shoulder 60. Tapered shoulder 44 of upstream ring 38 may be sized and configured to retain plug 28 by preventing plug 28 from traveling in an upstream direction beyond tapered shoulder 44 in a sealed state of system 10 shown in
One or more seals 62 may be positioned in one or more recesses 64 to fluidly seal the housing inner bore 24 at the connection point between segments 16 and 18. Housing segments 16 and 18 may be secured together at interface 66, which may include a threaded inner surface of segment 16 and a threaded outer surface of segment 18. In other embodiments, housing segments 16 and 18 may be secured by any fastening mechanism as readily understood by skilled artisans. In some embodiments, one or more housing segments may include a circumferential recess in the outer surface. For example, circumferential recess 67 may extend around the outer surface of housing segment 16, and circumferential recess 68 may extend around the outer surface of housing segment 18. Identifying information about the tool or job number may be stamped into recesses 67 and 68 where the outer diameter reduction reduces the wear on the stamped information.
Plug portion 12 may be configured to release plug 28 from sleeve 26 in response to a release event. The release event may be application of an upstream pressure within housing inner bore 24 upstream of sleeve 26 that meets or exceeds a release pressure value in the downstream direction on plug 28. The release pressure value may be the pressure required to overcome the frictional forces between plug 28 and a downstream retainer, such as tapered surface 60 of sleeve 26. The release pressure valve may be the pressure required to plastically deform plug 28 in such a way that the new outer diameter of the plug is equal or smaller than the inner diameter of ring 42. In some embodiments, the release pressure value may be in the range of 500 psi and 2,000 psi. In certain embodiments, the release pressure value may be less than or equal to 50% of a yield stress value of housing segment 16. For example, the housing segments of sealing system 10 may be formed of carbon steel, alloys, nickel steel, high yield steel, titanium, beryllium copper, and the release pressure value may be in the range of 500 psi to 2,000 psi. In other embodiments, the release pressure value may be 95% or less of an overpull to failure in the weakest cross-sectional area of the housing. As used herein, “overpull to failure” is the maximum pull that can be exerted on stuck drill pipe without causing failure in the drill string. Alternatively, the release event may be a mechanical or physical force exerted in a downstream direction on an upstream surface of plug 28. In embodiments in which plug 28 is formed of a dissolvable material, the release event may be introducing a fluid that dissolves or otherwise breaks down the plug 28. As used herein, “release event” means an occurrence that causes plug 28 to be released from sleeve 26. Once released from sleeve 26, the plug 28 may travel in a downstream direction into intermediate space 106. In some embodiments, the outer diameter or outer dimension of the plug 28 is less than the inner diameter of housing inner bore 24 such that plug 28 moves in the downstream direction more easily when released from sleeve 26.
With reference to
In some embodiments, such as the illustrated embodiment, the crown of the dome is disposed downstream of base 84 of rupture disc 30. Distal end 88 of base 84 may be positioned against downward facing shoulder 80 of housing segment 20, proximal end 90 of base 84 may be positioned near upper shoulder 82 of housing segment 22, and the crown of central portion 86 of rupture disc 30 may be positioned in housing inner bore 24 within housing segment 22. In these embodiments, rupture disc 30 may be configured to fracture at a lower pressure on its upstream side (inner surface 86b) than its downstream side (outer surface 86a).
In some embodiments, the dome shape of central portion 86 may include smooth, continuous outer and inner surfaces. In other embodiments, the dome shape of central portion 86 may include an outer surface formed of a plurality of facets defined by a plurality of seams, an inner surface formed of a plurality of facets defined by a plurality of seams, or both outer and inner surfaces formed of a plurality of facets defined by a plurality of seams. For example, in the illustrated embodiment, the dome shape of central portion 86 includes outer surface 86a formed of a plurality of facets and inner surface 86b that is smooth and continuous. As used herein, “facet” means a flat surface having a constant angular orientation, or a conical surface. As used herein “flat” means a substantially planar surface, which may or may not include insignificant deviations from the plan (e.g., a small bump or similar irregularity). As used herein, “conical surface” means a segment of a surface formed by moving one end of a straight line in a curve or in a circle while the other end of the straight line remains stationary.
Central portion 86 of rupture disc 30 fluidly seals housing inner bore 24 by extending across housing inner bore 24. One or more seals 92 may be positioned between rupture disc 30 and upper end 82 of housing member 22. One or more seals 94 may be positioned within one or more recesses 96 in housing member 22 to further fluidly seal the connection between housing members 20 and 22. In other embodiments, some or no seals are used at all whereby distal end 88 of base 84 of rupture disc 30 may be positioned against downward facing shoulder 80 of housing segment 20, and in this way, the rupture disc 30 fluidly seals housing inner bore 24. Housing segments 20 and 22 may be secured together at interface 98, which may include a threaded inner surface of segment 20 and a threaded outer surface of segment 22. In other embodiments, housing segments 20 and 22 may be secured by any fastening mechanism as readily understood by skilled artisans.
In certain embodiments, an inner surface of base 84 of rupture disc 30 is generally radially aligned with, or is disposed radially outward of, housing inner bore 24 immediately upstream and housing inner bore 24 immediately downstream of base 84. In other words, in these embodiments an inner diameter of base 84 may be equal to or greater than the inner diameter of housing inner bore 24 immediately above and below base 84. For example, in the illustrated embodiment, inner surface 84a of base 84 is disposed slightly radially outward of adjacent upstream portion 100 of housing inner bore 24 and adjacent downstream portion 102 of housing inner bore 24. In other words, an inner diameter of base 84 is slightly greater than the inner diameter of adjacent upstream portion 100 and adjacent downstream portion 102 of housing inner bore 24. In this embodiment, base 84 of rupture disc 30 is housed within the expanded diameter portion of housing inner bore 24 formed by shoulder 80 of housing segment 20 and upper end 82 of housing segment 22. In other embodiments, inner surface 84a of base 84 may be generally aligned with adjacent upstream portion 100 and/or adjacent downstream portion 102 of housing inner bore 24. In some embodiments, one or more housing segments may include a circumferential recess in the outer surface. For example, circumferential recess 103 may extend around the outer surface of housing segment 20, and circumferential recess 104 may extend around the outer surface of housing segment 22. Identifying information about the tool or job number may be stamped into recesses 103 and 104 where the outer diameter reduction reduces the wear on the stamped information.
Rupture disc 30 may be configured to fracture in response to a rupture event. The rupture event may be application of a pressure within housing inner bore 24 upstream of rupture disc 30 that meets or exceeds a rupture pressure value in the downstream direction on central portion 86 of rupture disc 30. In certain embodiments, the rupture pressure value is in the range of 500 psi and 2,000 psi. Alternatively, the rupture event may be a mechanical or physical force exerted in a downstream direction on the central portion 86 of rupture disc 30. In certain embodiments, intermediate space 106 is filled with air under hydrostatic surface pressure or at a vacuum pressure, and the rupture event is plug 28 mechanically hitting and crushing rupture disc 30. As used herein, “rupture event” means an occurrence that causes a change in the rupture disc that renders the rupture disc incapable of hydraulically sealing the housing inner bore. In embodiments including a plurality of facets on an inner and/or outer surface of central portion 86, rupture disc 30 may be configured to fracture along the plurality of seams in response to the rupture event. In this way, the number and size of the disc fragments generated by the rupture event may be controlled. For example, the plurality of seams may be configured to provide a greater number of smaller disc fragments, which eases the process of clearing the disc fragments from the wellbore.
In the sealed state shown in
With reference to
Referring to
With reference now to
When a user desires to restore fluid communication between distal portion 220 of wellbore 201 and surface 202, the user may create a release event to release plug 28 from sleeve 26. In one embodiment, the release event may be created by pumping a fluid into wellbore 201 to apply a pressure on plug 28 that meets or exceeds the release pressure value. For example, a fluid may be pumped into wellbore 201 to apply a pressure in the range of 500 psi to 2,000 psi to the upstream side of plug 28. Alternatively, the release event may be created by applying a mechanical or physical force on the plug 28 that exceeds the relevant frictional forces. With both types of release events, the release of plug 28 may in turn trigger a rupture event to fracture the central portion 86 of rupture disc 30 into a plurality of fragments 110 as described herein. Plug 28 clears the plurality of fragments 110 from the housing inner bore 24 of sealing system 10. Plug 28, sleeve 26, and/or the plurality of fragments 110 of rupture sub 30 may dissolve or be suspended in a dissolving or suspending agent. In this way, sealing system 10 enables selectively sealing an isolated portion of a wellbore and selectively reestablishing fluid communication between the isolated portion of the wellbore and the surface without the need to retrieve components of seal system 10.
Referring to
Except as otherwise described or illustrated, each of the components in this device has a generally cylindrical or tubular shape and may be formed of steel, another metal, or any other durable material. Portions of sealing system 10 may be formed of a wear resistant material, such as tungsten carbide or ceramic coated steel.
Each device described in this disclosure may include any combination of the described components, features, and/or functions of each of the individual device embodiments. Each method described in this disclosure may include any combination of the described steps in any order, including the absence of certain described steps and combinations of steps used in separate embodiments. Any range of numeric values disclosed herein includes any subrange therein. “Plurality” means two or more. “Above” and “below” shall each be construed to mean upstream and downstream, such that the directional orientation of the device is not limited to a vertical arrangement.
While preferred embodiments have been described, it is to be understood that the embodiments are illustrative only and that the scope of the invention is to be defined solely by the appended claims when accorded a full range of equivalents, many variations and modifications naturally occurring to those skilled in the art from a review hereof.
This application is a continuation of and claims priority to U.S. patent application Ser. No. 18/136,723, filed on 19 Apr. 2023, which is incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 18136723 | Apr 2023 | US |
| Child | 18766058 | US |
