This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
An annular blowout preventer (BOP) is installed on a wellhead to seal and control an oil and gas well during drilling operations. A drill string may be suspended inside the oil and gas well from a rig through the annular BOP into a wellbore. A drilling fluid is delivered through the drill string and returned up through an annulus between the drill string and a casing that lines the wellbore. In the event of a rapid invasion of formation fluid in the annulus, commonly known as a “kick,” the annular BOP may be actuated to seal the annulus and to control fluid pressure in the wellbore. In this way, the annular BOP may protect well equipment disposed above the annular BOP.
This summary is provided to introduce a selection of concepts that are further described below in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining or limiting the scope of the claimed subject matter as set forth in the claims.
In one embodiment, a packer assembly for an annular blowout preventer (BOP) includes an elastomeric sealing packer and multiple inserts that support the elastomeric sealing packer. Each insert of the multiple inserts includes an upper member and an intermediate member that are rotatably coupled to one another.
In one embodiment, an annular blowout preventer (BOP) includes a housing, a piston positioned within the housing, and a packer assembly positioned within the housing. The packer assembly includes a packer and multiple inserts that support the packer, and each insert of the multiple inserts comprises multiple members that are rotatably coupled to one another.
In one embodiment, a method of operating an annular blowout preventer (BOP) includes adjusting a piston of the annular BOP along an axial axis to exert a force on a packer assembly. The method also includes rotating an upper member of an insert of the packer assembly relative to an intermediate member of the insert of the packer assembly via a pin that extends along the axial axis in response to the force on the packer assembly to thereby compress a packer of the packer assembly.
Various features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying figures in which like characters represent like parts throughout the figures, wherein:
One or more specific embodiments of the present disclosure will be described below. These described embodiments are only exemplary of the present disclosure. Additionally, in an effort to provide a concise description of these exemplary embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
The present embodiments are generally related to annular blowout preventers (BOPs). In particular, the present embodiments are generally directed to an annular BOP that includes a housing that has an upper piece with a curved dome-shaped inside surface. An annular closure assembly is positioned within the housing, and the annular closure assembly includes an elastomeric sealing packer and multiple inserts. The annular closure assembly has a curved dome-shaped upper surface that is complementary to the curved dome-shaped inside surface of the upper piece of the housing. The multiple inserts include multiple upper members that are also curved to be complementary to the curved dome-shaped inside surface of the upper piece of the housing, and the multiple upper members form an upper iris (e.g., the multiple upper members rotate radially inwardly). The multiple inserts also include multiple lower members that form a lower iris (e.g., the multiple lower members rotate radially inwardly) and multiple intermediate members that are inclined along an axial axis to connect a respective upper member of the multiple upper members to a respective lower member of the multiple lower members.
The annular BOP includes a piston positioned within the housing, and the piston has a tapered inner surface (e.g., frusto-conical inner surface) that is configured to slidingly engage an outside surface of the annular closure assembly. In operation, the piston moves upwards within the housing so that the tapered inner surface applies a force to the outside surface of the annular closure assembly. As a result, the multiple upper members of the multiple inserts are forced against the curved dome-shaped inside surface of the upper piece of the housing. This causes the multiple upper members to pivot or to rotate with respect to the multiple intermediate members such that inside ends of the multiple upper members are brought closer together (e.g., a diameter of an opening defined by the inside ends of the multiple upper members is reduced). In some embodiments, the multiple lower members also pivot or to rotate with respect to the multiple intermediate members such that inside ends of the multiple lower members are brought closer together (e.g., a diameter of an opening defined by the inside ends of the multiple lower members is reduced). In turn, this causes the multiple inserts to squeeze the elastomeric sealing packer such that an inside surface of the elastomeric sealing packer seals against a conduit within a central bore of the annular BOP (or seals against itself across the central bore of the annular BOP) to thereby block fluid flow through the central bore of the annular BOP.
While the disclosed embodiments are described in the context of a drilling system and drilling operations to facilitate discussion, it should be appreciated that the annular BOP may be adapted for use in other contexts and other operations. For example, the annular BOP may be used in a pressure control equipment (PCE) stack that is coupled to and/or positioned vertically above a wellhead during various intervention operations (e.g., inspection or service operations), such as wireline operations in which a tool supported on a wireline is lowered through the PCE stack to enable inspection and/or maintenance of a well. In such cases, the annular BOP may be in the closed position (e.g., to seal about the wireline extending through the PCE stack) to isolate the environment, as well as other surface equipment, from pressurized fluid within the well. In the present disclosure, a conduit may be any of a variety of tubular or cylindrical structures, such as a drill string, wireline, Streamline™, slickline, coiled tubing, or other spoolable rod.
With the foregoing in mind,
To facilitate discussion, the BOP assembly 5 and its components may be described with reference to an axial axis or direction 1, a radial axis or direction 2, and a circumferential axis or direction 3. The BOP assembly 5 may include one or more annular BOPs 10. Although not shown for purposes of image clarity, the BOP assembly 5 may also include one or more ram BOPs (e.g., shear ram, blind ram, blind shear ram, or pipe ram BOPs). A central bore 12 (e.g., flow bore) extends through the one or more annular BOPs 10. As discussed in more detail herein, at least one of the annular BOPs 10 includes an annular closure assembly (e.g., packer assembly) that is configured to be mechanically squeezed radially inwardly to seal about the conduit 9 extending through the central bore 12 to block fluid flow through the central bore 12. The disclosed embodiments include annular BOPs 10 with the annular closure assembly having various features, such as multiple inserts coupled to an elastomeric sealing packer in a configuration that facilitates iris style closing.
With reference to
The lower piece 50 of the housing 20 defines a lower orifice 52 at a lower end of the central bore 12. The lower piece 50 of the housing 20 has a first portion 54 (e.g., having a first inner diameter) that defines a threaded inside surface 56 (e.g., radially-inner surface; annular surface) that is configured to threadably engage the threaded outside surface 42 of the extended ring structure 38 of the upper piece 30 of the housing 20. The lower piece 50 of the housing 20 also has a second portion 60 (e.g., having a second inner diameter, which may be smaller than the first inner diameter). The lower piece 50 further defines an interior step 62 (e.g., radially-extending surface; annular surface) that extends between the first portion 54 and the second portion 60.
With reference to
The elastomeric sealing packer 80 may be positioned relative to the multiple inserts in a manner that enables the multiple inserts to support the elastomeric sealing packer 80 and to drive the elastomeric sealing packer 80 radially-inwardly into the central bore 12. For example, the elastomeric sealing packer 80 may be circumferentially surrounded by the multiple inserts, the elastomeric sealing packer 80 may be molded around the multiple inserts, and/or the multiple inserts may be embedded and/or adhered to a surface (e.g., radially-outer surface; annular surface) of the elastomeric sealing packer 80. In some embodiments, the elastomeric sealing packer 80 may be circumferentially surrounded by the multiple inserts in a way that blocks contact between all or at least some of the elastomeric sealing packer 80 and the housing 20 at least while the annular BOP 10 is in the open configuration of
The annular closure assembly 70 has a dome-shaped upper portion with an upper surface 82 (e.g., annular surface), a lower portion (e.g., lower end) with a lower surface 88 (e.g., annular surface), and an intermediate portion with an intermediate outside surface 90 (e.g., annular surface; frusto-conical surface; radially-outer surface). The annular closure assembly 70 defines a maximum diameter 84 (e.g., outer diameter) that is located generally between the dome-shaped upper portion and the lower portion along the axial axis 1, and a smaller diameter 86 (e.g., outer diameter) that is located at the lower portion and that is less than the maximum diameter 84. As shown, the intermediate portion with the intermediate outside surface 90 tapers to transition from the maximum diameter 84 to the smaller diameter 86. The elastomeric sealing packer 80 also defines an inner surface 92 (e.g., radially-inner surface; annular surface) of the annular closure assembly 70, and the inner surface 92 defines the central bore 12 and is configured to engage a conduit in the central bore 12 and/or seal against itself across the central bore 12 while the annular BOP 10 is in the closed configuration, as shown in
As shown in
Each of the upper members 120 defines a respective upper outside surface 126 (e.g., annular surface; dome-shaped surface; radially-outer surface) and a respective upper inside surface 128 (e.g., annular surface; radially-inner surface; see
The upper ends 106 of the intermediate members 100 are rotatably (e.g., pivotally) coupled to the outside ends 124 of the upper members 120. The upper ends 106 of the intermediate members 100 may be rotatably coupled to the outside ends 124 of the upper members 120 via any suitable connectors, such as pins. For example, as shown in
Each of the lower members 140 defines a respective upper surface 146 (e.g., annular surface; axially-facing surface) and a respective lower surface 148 (e.g., annular surface; axially-facing surface). In cases in which the lower members 140 are exposed (e.g., not covered by the thin layer of the elastomeric sealing packer 80), the lower surface 88 of the annular closure assembly 70 is formed at least in part by the lower surfaces 148 of the lower members 140. Each of the lower members 140 extends from a respective outside end 142 (e.g., radially-outer end) to a respective inside end 144 (e.g., radially-inner end). The respective outside end 142 and the respective inside end 144 are offset along the circumferential axis 3 at least while the annular BOP 10 is in the open configuration (e.g., an axis extending from a center of the respective outside end 142 to a center of the respective inside end 144 is angled with respect to the radial axis 2 and is not parallel to the radial axis 2; the lower members 140 are rotated in the circumferential direction 3).
The lower ends 108 of the intermediate members 100 are rotatably (e.g., pivotally) coupled to the lower members 140. The lower ends 108 of the intermediate members 100 may be rotatably coupled to the outside ends 142 of the lower members 140 via any suitable connectors, such as pins. For example, as shown in
The pins 130, 150 may enable the upper members 120 and the lower members 140 to rotate independently of one another and relative to the intermediate members 100. The pins 130, 150 may be aligned with or parallel to (e.g., parallel or substantially parallel, such as within 1, 2, 3, 4, or 5 degrees of parallel to) the axial axis 1, and thus, the pins 130, 150 may enable the upper members 120 and the lower members 140 to rotate in the circumferential direction 3. The pins 130, 150 may have respective central axes 131, 151 that define respective axes of rotation for the upper members 140. In some embodiments, the pins 130, 150 are integrally formed with the respective members 100, 120, 140. In some embodiments, the pins 130, 150 are coupled to (e.g., via fasteners, such as bolts or welds) the respective members 100, 120, 140.
As shown in
The tapered inside piston surface 170 is configured to contact the annular closure assembly 70. In particular, the tapered inside piston surface 170 is configured to contact the annular closure assembly 70 (e.g., at least a portion of the intermediate outside surface 90 of the annular closure assembly 70, which is tapered or inclined in a complementary manner) while the annular BOP 10 is in the open configuration, the closed configuration, and any position therebetween. In cases in which the inserts are exposed (e.g., not covered by the thin layer of the elastomeric sealing packer 80), the tapered inside piston surface 170 is configured to contact at least portions of the inserts (e.g., at least the intermediate outside surfaces 104 of the intermediate members 100).
Furthermore, as discussed in more detail herein, the tapered inside piston surface 170 is configured to exert a force on the annular closure assembly 70 to drive the annular closure assembly 70 inwardly within the housing 20 to adjust the annular BOP 10 from the closed configuration to the open configuration.
As shown in
In operation, to adjust the annular BOP 10 from the open configuration to the closed configuration, the lower cavity 220 is pressurized via delivery of hydraulic fluid into the lower cavity 220. The hydraulic fluid contacts and exerts a force on the lower piston head surface 186 to drive the piston 160 upward within the housing 20. As the piston 160 moves upward within the housing 20, the tapered inside piston surface 170 contacts and exerts a force on at least a portion of the intermediate outside surface 90 of the annular closure assembly 70. Because the upper surface 82 of the annular closure assembly 70 is positioned against the first inside surface 34 of the upper piece 30 of the housing 20, the annular closure assembly 70 is blocked from moving upward within the housing 20. Instead, the upper surface 82 of the annular closure assembly 70 slides against the first inside surface 34 of the upper piece 30 of the housing, and the annular closure assembly 70 is directed to move radially inwardly into the central bore 12 of the annular BOP 10 as the tapered inside piston surface 170 contacts and exerts the force on at least the portion of the intermediate outside surface 90 of the annular closure assembly 70. In order for the annular closure assembly 70 to move radially inwardly into the central bore 12 of the annular BOP 10 in this way, the members 100, 120, 140 of the inserts of the annular closure assembly 70 rotate with respect to one another (e.g., in a first rotational direction via the pins 130, 150) as the tapered inside piston surface 170 contacts and exerts the force on at least the portion of the intermediate outside surface 90 of the annular closure assembly 70. The rotation of the members 100, 120, 140 of the inserts of the annular closure assembly 70 causes cause the inside ends 122 of the upper members 120 to move closer together (e.g., reduce the inner diameter defined by the inside ends 122 of the upper members 120) and the inside ends 144 of the lower members 140 to move closer together (e.g., reduce the inner diameter defined by the inside ends 144 of the lower members 140), thereby squeezing the elastomeric sealing packer 80 to cause the elastomeric sealing packer 80 to seal the central bore 12 of the annular BOP 10.
To adjust the annular BOP 10 from the closed configuration to the open configuration the upper cavity 210 is pressurized via delivery of hydraulic fluid into the upper cavity 210. The hydraulic fluid contacts and exerts a force on the upper piston head surface 184 to drive the piston 160 downward within the housing 20. This results in the annular closure assembly 70 moving downward and expanding radially (e.g., due to rotation of the members 100, 120, 140 of the inserts of the annular closure assembly 70 in a second rotational direction via the pins 130, 150 and the expansion of the elastomeric sealing packer 80) within the housing 20 to open the central bore 12 of the annular BOP 10.
In some embodiments, the only relative movement between the members 100, 120, 140 of the inserts of the annular closure assembly 70 is due to the rotation (e.g., about the pins 130, 150) and no other relative movement occurs (e.g., no bending along the axial axis 1, such as no bending along the axial axis 1 at joints between the members 100, 120, 140 of a particular insert) as the annular BOP 10 adjusts between the open configuration and the closed configuration. In some embodiments, a height of the inserts along the axial axis 1 does not change as the annular BOP 10 adjusts between the open configuration and the closed configuration; however, a maximum diameter defined by the inserts (which generally corresponds to the maximum diameter 84 of the annular closure assembly 70) along the radial axis 2 changes as the annular BOP 10 adjusts between the open configuration and the closed configuration (e.g., larger in the open configuration and smaller in the closed configuration). Additionally, the annular closure assembly 70 moves upwardly and radially inwardly within the housing as the annular BOP adjusts from the open configuration to the closed configuration.
While the disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the disclosure is not intended to be limited to the particular forms disclosed. Rather, the disclosure is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the following appended claims.
The techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function] . . . ” or “step for [perform]ing [a function] . . . ”, it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f).
This application claims priority to and the benefit of U.S. Provisional Application No. 63/070,058, entitled “ANNULAR BLOWOUT PREVENTER” and filed Aug. 25, 2020, which is incorporated by reference herein in its entirety for all purposes.
Filing Document | Filing Date | Country | Kind |
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PCT/US2021/047238 | 8/24/2021 | WO |
Number | Date | Country | |
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63070058 | Aug 2020 | US |