Patent Grant
9765581
In oilfield exploration and production operations, various oilfield tubular members are used to perform important tasks, including, but not limited to, drilling the wellbore and casing a drilled wellbore. For example, a long assembly of drill pipes, known in the industry as a drill string, may be used to rotate a drill bit at a distal end to create the wellbore. Furthermore, after a wellbore has been created, a casing string may be disposed downhole into the wellbore and cemented in place to stabilize, reinforce, or isolate (among other functions) portions of the wellbore. As such, strings of drill pipe and casing may be connected together, such as end-to-end by threaded connections, in which a male “pin” member of a first tubular member is configured to threadably engage a corresponding female “box” member of a second tubular member. Alternatively, a casing string may be made-up of a series of male-male ended casing joints coupled together by female-female couplers. The process by which the threaded connections are assembled is called “making-up” a threaded connection, and the process by which the connections are disassembled is referred to “breaking-out” the threaded connection. As would be understood by one having ordinary skill, individual pieces (or “joints”) of oilfield tubular members may come in a variety of weights, diameters, configurations, and lengths.
Referring to
Additionally, the lifting apparatus 105 may be coupled below the traveling block 103 (and/or a top drive if present) to selectively grab or release a tubular member 111 as the tubular member 111 is to be raised and/or lowered within and from the derrick 102. As such, the top drive may include one or more guiding rails and/or a track disposed adjacent to the top drive, in which the guiding rails or track may be used to support and guide the top drive as the top drive is raised and/or lowered within the derrick. An example of a top drive is disclosed within U.S. Pat. No. 4,449,596, filed on Aug. 3, 1982, and entitled “Drilling of Wells with Top Drive Unit,” which is incorporated herein by reference.
Typically, a lifting apparatus 105 includes movable gripping members (e.g., slip assemblies) attached thereto and movable between a retracted (e.g., disengaged) position and an engaged position. In the engaged position, the lifting apparatus 105 supports the tubular member 111 such the tubular member 111 may be lifted and/or lowered, and rotated if so equipped, e.g., by using a lifting apparatus that is a tubular (e.g., casing) running tool connected to the quill of the top drive. In the retracted position, the lifting apparatus 105 may release the tubular member 111 and move away therefrom to allow the tubular member 111 to be engaged with or removed from the lifting apparatus 105 and/or the gripping apparatus 107. For example, the lifting apparatus 105 may release the tubular member 111 after the tubular member 111 is threadably connected to a tubular string 115 supported by the gripping apparatus 107 (e.g., slip assembly or “spider”) at the rig floor at the floor of the drilling rig 101.
Further, in an embodiment in which the drilling rig 101 includes a top drive and a tubular running tool, the tubular member 111 may be supported and gripped by the tubular running tool connected to the quill of the top drive. For example, the tubular running tool may include one or more gripping members that may move radially inward and/or radially outward. In such embodiments, these gripping members of a tubular running tool may move radially outward to grip an internal surface of the tubular member 111, such as with an internal gripping device and/or the gripping members of the tubular running tool may move radially inward to grip an external surface of the tubular member 111, such as with an external gripping device, however so equipped.
As such, the gripping apparatus 107 of the drilling rig 101 may be used to support and suspend the tubular string 115, e.g., by gripping, from the drilling rig 101, e.g., supported by the rig floor 109 or by a rotary table thereof. The gripping apparatus 107 may be disposed within the rig floor 109, such as flush with the rig floor 109, or may extend above the rig floor 109, as shown. As such, the gripping apparatus 107 may be used to suspend the tubular string 115, e.g., while one or more tubular members 111 are connected or disconnected from the tubular string 115.
Referring now to
The illustrated gripping device 201 includes a bowl 203 with a plurality of slip assemblies 205 movably disposed therein. Specifically, the slip assemblies 205 may be connected to a ring 207, in which the ring 207 may be connected to the bowl 203 through an actuator (e.g., actuator rods) 209. Actuator may be actuated, such as electrically actuated and/or fluidly (e.g., hydraulically) actuated, to move up and/or down with respect to the bowl 203, in which the slip assemblies 205 connected to the ring 207 may correspondingly move up and/or down with respect to the bowl 203.
The illustrated slip assemblies 205 are designed to engage and contact the inner tapered surface of the bowl 203 when moving with respect to the bowl 203. Bowl 203 is shown as a continuous surface but may comprise non-continuous surfaces (e.g., a surface adjacent to the rear of each slip assembly 205). Thus, as the slip assemblies 205 move up or down with respect to the bowl 203, the slip assemblies 205 may travel down along an inner surface of the bowl 203. With this movement, an inner surface (e.g., die) of the slip assemblies 205 will grip a tubular member 211 disposed within the gripping device 201. The slip assemblies 205 may have a gripping surface (e.g., teeth), such as a die, on the inner surface to facilitate the gripping of the tubular member 211. After the tubular member 211 is supported by the gripping device 201, additional tubular members may be connected or disconnected from the tubular member 211.
As shown with respect to
A tubular string of tubular members may be heavy, in the magnitude of several hundreds of thousands of pounds. As such, the gripping devices handling these tubular strings, in addition to the drilling rig and other components thereof, must be equipped to handle such weight. Further, the tubular string may have one or more different tubular members or tubular sections, such as including a section within the tubular string having casing, drill pipe, and/or a landing string, in which each of these sections of the tubular string may have different dimensions (internal diameter and/or external diameter). As such, effectively handling tubular members having different dimensions within an oilfield environment remains a priority to increase the efficiency and effectiveness of tubular handling equipment.
For a detailed description of the preferred embodiments of the invention, reference will now be made to the accompanying drawings in which:
The following discussion is directed to various embodiments of the invention. The drawing figures are not necessarily to scale. Certain features of the embodiments may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in the interest of clarity and conciseness. Although one or more of these embodiments may be preferred, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure, including the claims. It is to be fully recognized that the different teachings of the embodiments discussed below may be employed separately or in any suitable combination to produce desired results. In addition, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to intimate that the scope of the disclosure, including the claims, is limited to that embodiment.
Certain terms are used throughout the following description and claims to refer to particular features or components. As one skilled in the art will appreciate, different persons may refer to the same feature or component by different names. This document does not intend to distinguish between components or features that differ in name but not structure or function. The drawing figures are not necessarily to scale. Certain features and components herein may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in interest of clarity and conciseness.
In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct coupling, and the “connect” or “connects” is intended to mean either an indirect or direct connection, unless otherwise denoted. In addition, the terms “axial” and “axially” generally mean along or parallel to a central axis (e.g., central axis of a body or a port), while the terms “radial” and “radially” generally mean perpendicular to the central axis. The use of “top,” “bottom,” “above,” “below,” and variations of these terms is made for convenience, but does not require any particular orientation of the components.
In accordance with various aspects disclosed herein, the present disclosure relates to a tubular gripping apparatus that may be used to grip and/or support a tubular member, such as within an oilfield exploration and production operation environment discussed above. The tubular gripping apparatus may include a main bowl with a movable bowl movably received within the main bowl. Further, a plurality of slip assemblies may be movably received within the movable bowl, in which the plurality of slip assemblies may be used to engage an outer surface of a tubular member. The tubular gripping apparatus may be movable between an engaged position, in which the plurality of slip assemblies are engaged with the outer surface of the tubular member, and a disengaged position, in which the plurality of slip assemblies are not engaged and/or in contact with the outer surface of the tubular member.
As such, when moving between the engaged and disengaged positions, the movable bowl may be movable between an upper position and a lower position with respect to the main bowl, in which the movable bowl may be disposed in the lower position when the plurality of slip assemblies are engaged with the outer surface of the tubular member, and the movable bowl may be disposed in the upper position when the plurality of slip assemblies are not engaged and/or in contact with the outer surface of the tubular member. By including a main bowl, a movable bowl, and/or a plurality of slip assemblies, a tubular gripping apparatus in accordance with one or more embodiments of the present disclosure may be able to engage, grip, and support tubular members having a variety of shapes, sizes, and/or dimensions. For example, a tubular gripping apparatus in accordance with one or more embodiments of the present disclosure may be able to engage, grip, and support tubular members having an outer diameter ranging between about 7 inches (about 18 cm) to about 20 inches (about 51 cm) without the need to change any components of the tubular gripping apparatus.
Referring now to
Depending on the size of the tubular member used with the apparatus 301, the apparatus 301 may engage, grip, and/or support the tubular member at any position shown in
As shown, the illustrated apparatus 301, which may be a lifting apparatus (e.g., 105 in
The inner surface 311 of the main bowl 303 may be tapered with respect to the axis 300, such as by having the inner surface 311 skewed at an angle with respect to the axis 300. For example, the main bowl 303 may have a smooth, non-stepped profile, tapered inner surface 311, or at least a portion of the inner surface 311 of the main bowl 303 may have a smooth, non-stepped, tapered profile. As such, the main bowl 303 may be used to enable the apparatus 301 to engage a range of tubular members having different dimensions included and received within the main bowl 303. However, those having ordinary skill in the art will appreciate that the present disclosure is not so limited, as other shapes and profiles, such as a stepped (e.g., rapid advance) profile, may be used for the inner surface of the main bowl without departing from the scope of the present disclosure.
Further, the apparatus 301 may include a movable bowl 313 that may be movably received within the main bowl 303. For example, the movable bowl 313 may be able to move between an upper position, as shown in
The movable bowl 313 may be formed such that a top opening 319 of the bore 317 is formed at a top side of the movable bowl 313, and a bottom opening of the bore 317 is formed at a bottom side of the movable bowl 313. Further, the illustrated movable bowl 313 may have an inner surface 321 that extends between the top opening 319 to the bottom opening of the movable bowl 313. As shown in
Similar to the main bowl 303, the inner surface 321 of the movable bowl 313 may be tapered with respect to the axis 300, such as by having the inner surface 321 skewed at an angle with respect to the axis 300. For example, movable bowl 313 may have a smooth, non-stepped profile, tapered inner surface 321, or at least a portion of the inner surface 321 of the movable bowl 313 may have a smooth, non-stepped, tapered profile. As such, the movable bowl 313 may be used to enable the apparatus 301 to engage a range of tubular members having different dimensions included and received within the movable bowl 313. However, those having ordinary skill in the art will appreciate that the present disclosure is not so limited, as other shapes and profiles, such as a stepped (e.g., rapid advance) profile, may be used for the inner surface of the movable bowl without departing from the scope of the present disclosure.
The plurality of bowl segments 315 may be movable with respect to the main bowl 303 (e.g., in-and-out of the main bowl 303), such as by having the bowl segments 315 movably received within the main bowl 303 and/or movably connected to the main bowl 303. Specifically, the bowl segments 315 may be movable in a radial direction with respect to the main bowl 303 (e.g., towards and/or away from the axis 300), and/or the bowl segments 315 may be movable in a longitudinal direction with respect to the main bowl 303 (e.g., along the axis 300). For example, by having the bowl segments 315 movably received and/or movably connected to the main bowl 303, the bowl segments 315 may be able to “slide” towards and/or away from the axis 300, e.g., move along the inner surface 311 of the main bowl 303. Further, the bowl segments 315 may be restricted from lateral movement in the bore 305 (e.g., movement about the axis 300), for example, while still allowing for movement towards and/or away from axis 300 (e.g., radial movement relative to axis 300 of the bore 305 of the main bowl 303).
The bowl segments 315 may each have multiple surfaces defined thereon, such as by having the inner surface 321 and an outer surface 323. As shown, the inner surface 321 of the bowl segments 315 is defined as a surface on the bowl segments 315 that is exposed toward the axis 300, and the outer surface 323 of the bowl segments 315 is defined as a surface on the bowl segments 315 that is exposed away from the axis 300 (e.g., toward the inner surface 311 of the main bowl 303). As discussed above, in accordance with one or more embodiments of the present disclosure, one or more of the surfaces of the bowl segments 315 may be tapered with respect to the axis 300. For example, in one or more embodiments, as shown in
The depicted apparatus 301 may further include a plurality of slip assemblies 331, in which the slip assemblies 331 may be movable with respect to the main bowl 303 and/or the movable bowl 313 (e.g., in-and-out of the main bowl 303 and/or the movable bowl 313). For example, the slip assemblies 331 may be movably received within the main bowl 303 and/or the movable bowl 313, such as movably connected to the main bowl 303 and/or the movable bowl 313. Specifically, the slip assemblies 331 may be movable in a radial direction with respect to the main bowl 303 and/or the movable bowl 313 (e.g., towards and/or away from the axis 300), and/or the slip assemblies 331 may be movable in a longitudinal direction with respect to the main bowl 303 and/or the movable bowl 313 (e.g., along the axis 300).
For example, by having the slip assemblies 331 movably connected to the movable bowl 313, the slip assemblies 331 may be able to “slide” towards and/or away from the axis 300, e.g., move along the inner surface 321 of the movable bowl 313. As such, the slip assemblies 331 may engage a tubular member included within the apparatus 301, such as engaging an outer surface of a tubular member received within the apparatus 301. Further, the slip assemblies 331 may be restricted from lateral movement in the bore 305 of the main bowl 303 and/or the bore 317 of the movable bowl 313 (e.g., movement about the axis 300), for example, while still allowing for movement towards and/or away from axis 300 (e.g., radial movement relative to axis 300).
The slip assemblies 331 may each have multiple surfaces defined thereon, such as by having an inner surface 333 and an outer surface 335. As shown, the inner surface 333 of the slip assemblies 331 is defined as a surface on the slip assemblies 331 that is exposed toward the axis 300, and the outer surface 335 of the slip assemblies 331 is defined as a surface on the slip assemblies 331 that is exposed away from the axis 300 (e.g., toward the inner surface 321 of the movable bowl 313).
In accordance with one or more embodiments of the present disclosure, one or more of the surfaces of the slip assemblies 331 may be tapered with respect to the axis 300. For example, in one or more embodiments, as shown in
Further, the inner surface 333 of the slip assemblies 331 may include a die column, such as to facilitate engagement of the slip assemblies 331 with the outer surface of a tubular member. For example, the inner surface 333 of the slip assemblies 331 is shown including a single die column 337, in which the die column 337 may be used to grip and “bite” into the outer surface of the tubular member. By including only a single die column 337 on the slip assemblies 331, this arrangement may facilitate the slip assemblies 331 being able to engage and grip the outer surface of tubular members having a range of sizes. Those having ordinary skill in the art will appreciate that the present disclosure is not so limited though, as more than one die column may be included with the slip assemblies without departing from the scope of the present disclosure. For example, with reference to
As discussed above, the inner surface 311 of the main bowl 303 and/or the inner surface 321 of the movable bowl 313 may be tapered with respect to the axis 300 of the apparatus 301. As such, the inner surface 311 of the main bowl 303 and the inner surface 321 of the movable bowl 313 may be disposed at substantially the same angle of taper with respect to the axis 300 of the apparatus 301. Alternatively, the inner surface 311 of the main bowl 303 may include a larger angle of taper than the inner surface 321 of the movable bowl 313 with respect to the axis 300, and/or the inner surface 311 of the main bowl 303 may include a smaller angle of taper than the inner surface 321 of the movable bowl 313 with respect to the axis 300. Accordingly, the present disclosure contemplates other configurations and embodiments other than those shown in
Referring still to
Further, in an embodiment in which the movable bowl 313 includes the plurality of bowl segments 315, the bowl segments 315 may be movably connected to the movable bowl timing ring 341. As such, the movable bowl timing ring 341 may enable the apparatus 301 to have substantially similar control over the bowl segments 315, such as when the bowl segments 315 are moving in the longitudinal direction along the axis 300 of the apparatus. As shown, a pin-and-link mechanism 343 may be used to enable the bowl segments 315 to move in the radial direction with respect to the axis 300. Additionally or alternatively, the bowl segments 315 may be able to move in the longitudinal direction along the axis 300, such as when the movable bowl timing ring 341 moves in the longitudinal direction along the axis 300. However, those having ordinary skill in the art will appreciate that other mechanisms or connections may be used to movably connect the bowl segments to the movable bowl timing ring and/or the main bowl. For example, in accordance with embodiments disclosed herein, a slide mechanism may be used to movably connect the bowl segments to the movable bowl timing ring. As such, the present disclosure contemplates other structures and/or arrangements for the apparatus without departing from the scope of the present disclosure.
Furthermore, the slip assembly timing ring 351 may be movably connected to the main bowl 303 and/or the movable bowl 313. In particular, the slip assembly timing ring 351 may be connected between the main bowl 303 and the movable bowl 313, in which the slip assembly timing ring 351 may be movable, such as between an upper position and a lower position, with respect to the main bowl 303. For example, the slip assembly timing ring 351 may be able to move in a longitudinal direction (i.e., vertically) along the axis 300.
The plurality of slip assemblies 331 may be movably connected to the slip assembly timing ring 351. As such, the slip assembly timing ring 351 may enable the apparatus 301 to have substantially similar control over the slip assemblies 331, such as when the slip assemblies 331 are moving in the longitudinal direction along the axis 300 of the apparatus. As shown, a pin-and-link mechanism 353 may be used to enable the slip assemblies 331 to move in the radial direction with respect to the axis 300. Additionally or alternatively, the slip assemblies 331 may be able to move in the longitudinal direction along the axis 300, such as when the slip assembly timing ring 351 moves in the longitudinal direction along the axis 300. However, those having ordinary skill in the art will appreciate that other mechanisms or connections may be used to movably connect the slip assemblies to the slip assembly timing ring, the movable bowl, and/or the main bowl. For example, in accordance with embodiments disclosed herein, a slide mechanism may be used to movably connect the slip assemblies to the slip assembly timing ring. As such, the present disclosure contemplates other structures and/or arrangements for the apparatus without departing from the scope of the present disclosure.
In accordance with one or more embodiments of the present disclosure, to have the movable bowl timing ring 341 movably connected to the main bowl 303, the apparatus 301 may include a plurality of guide cylinders 345. The guide cylinders 345 may be connected between the movable bowl timing ring 341 and the main bowl 303, in which the guide cylinders 345 may be movable, such as between an upper position and a lower position, with respect to the main bowl 303. As shown, the guide cylinders 345 may extend from the main bowl 303, such as from the top side 307 of the main bowl 303, in which the guide cylinders 345 may be substantially parallel with the axis 300. As such, in one or more embodiments, the movable bowl timing ring 341 may be attached to the top end of the guide cylinders 345, in which the guide cylinders 345 may be able to move in the longitudinal direction along the axis 300. The movement of the guide cylinders 345 may enable the movement of the movable bowl timing ring 341.
Further, in accordance with one or more embodiments of the present disclosure, to have the slip assembly timing ring 351 movably connected to the main bowl 303 and/or the movable bowl 313, the apparatus 301 may include a plurality of guide rods 355. The guide rods 355 may be connected between the slip assembly timing ring 351 and the main bowl 303, in which the guide rods 355 may be movable, such as between an upper position and a lower position, with respect to the main bowl 303. As shown, the guide rods 355 may extend from the main bowl 303, such as from the top side 307 of the main bowl 303, in which the guide rods 355 may be substantially parallel with the axis 300. As such, in one or more embodiments, the slip assembly timing ring 351 may be attached to the top end of the guide rods 355, in which the guide rods 355 may be able to move in the longitudinal direction along the axis 300. The movement of the guide rods 355 may enable the movement of the slip assembly timing ring 351.
As shown in
Referring still to
In some embodiments, as the guide cylinders 345, the guide rods 355, and/or the actuator rods 361 may move in the longitudinal direction along the axis 300, the guide cylinders 345, the guide rods 355, and/or the actuator rods 361 may extend into and out of one or more cavities formed within the main bowl 303. These cavities may be able to retain the guide cylinders 345, the guide rods 355, and/or the actuator rods 361 within the main bowl 303 after the guide cylinders 345, the guide rods 355, and/or the actuator rods 361 have moved longitudinally downward along the axis 300, such as moved into the lower position. Furthermore, in selected embodiments, the movable bowl timing ring 341 and/or the slip assembly timing ring 351 may be powered mechanically, hydraulically, pneumatically, and/or electrically.
In selected embodiments, when using hydraulic power, fluids may be pumped into and/or out of the cavities to move one or more of the guide cylinders 345, the guide rods 355, and/or the actuator rods 361 downward and/or upward, and therefore also moving the movable bowl timing ring 341 and/or the slip assembly timing ring 351 connected thereto downward and/or upward. Further, in selected embodiments, when using mechanical power, one or more of the guide cylinders 345, the guide rods 355, and/or the actuator rods 361, such as the actuator rods 361 shown in
In one or more embodiments of the apparatus 301 including the movable bowl timing ring 341 and the slip assembly timing ring 351, the movable bowl timing ring 341 may be biased away from the slip assembly timing ring 351. In particular, with respect to
By including the movable bowl timing ring 341 and the slip assembly timing ring 351, the movement of the components within the apparatus 301 may be synchronized with respect to each other. Further, by biasing the movable bowl timing ring 341 and the slip assembly timing ring 351 away from each other, the movable bowl timing ring 341 and the slip assembly timing ring 351 may remain separated from each other until contact with the outer surface of a tubular member is achieved. For example, when in use and moving between an upper position and a lower position, such as when moving between a disengaged position to an engaged position, the movable bowl timing ring 341 and the slip assembly timing ring 351 may maintain a separation therebetween. As such, when moving downward, the movable bowl timing ring 341 may be lowered until the movable bowl timing ring 341 contacts the main bowl 303, thereby preventing any further movement, or the plurality of bowl segments 315 connected to the movable bowl timing ring 341 contact an outer surface of a tubular member within the apparatus 301.
At this point, the slip assembly timing ring 351 may continue to be lowered with respect to the movable bowl timing ring 341 such that the plurality of slip assemblies 331 connected to the slip assembly timing ring 351 contact and engage the outer surface of the tubular member within the apparatus 301. This movement may enable the slip assemblies 331 to achieve a preload engagement and bite within the outer surface of the tubular member such that the apparatus 301 may support the tubular member. Further, by biasing the movable bowl timing ring 341 and the slip assembly timing ring 351 away from each other, the slip assembly timing ring 351 may be moved, such as through the use of the plurality of actuator rods 361, in which the movable bowl timing ring 341 may follow the movement of the slip assembly timing ring 351 from the biasing force acting thereupon.
Referring now to
Accordingly, by including a main bowl, a movable bowl, and/or a plurality of slip assemblies, a tubular gripping apparatus in accordance with one or more embodiments of the present disclosure may be able to engage, grip, and support tubular members having a variety of shapes, sizes, and/or dimensions. For example, a tubular gripping apparatus in accordance with one or more embodiments of the present disclosure may be able to engage, grip, and support tubular members having an outer diameter ranging between about 7 inches (about 18 cm) to about 20 inches (about 51 cm), such as a tubular member having an outer diameter of about 8.5 inches (about 21.6 cm), without the need to change any components of the tubular gripping apparatus.
In accordance with one or more embodiments of the present disclosure, a tubular gripping apparatus may be able to adjust (e.g., self-adjust) for use with tubular members having multiple sizes. For example, with reference to
Further, for a tubular member, such as having an outer diameter ranging between about 7 inches (about 18 cm) to about 8.5 inches (about 21.6 cm), a movable bowl may move downward and/or radially inward with respect to a main bowl until the movable bowl and/or bowl segments of the movable bowl contact the main bowl of the tubular gripping apparatus. After the movable bowl and/or bowl segments of the movable bowl contact the main bowl, a plurality of slip assemblies may move downward and/or radially inward with respect to the main bowl and/or movable bowl such that the plurality of slip assemblies contact, engage, and/or grip the outer surface of the tubular member such that the tubular gripping apparatus may support the tubular member. Accordingly, though one having ordinary skill in the art will appreciate that the present disclosure is not limited to the above examples and dimensions, by including a main bowl, a movable bowl, and/or a plurality of slip assemblies, a tubular gripping apparatus in accordance with one or more embodiments of the present disclosure may be able to engage, grip, and support tubular members having a variety of shapes, sizes, and/or dimensions.
Although the present invention has been described with respect to specific details, it is not intended that such details should be regarded as limitations on the scope of the invention, except to the extent that they are included in the accompanying claims.
The present application claims benefit to U.S. Provisional Patent Application No. 61/914,361, filed on Dec. 10, 2013. This priority application is hereby incorporated herein by reference in its entirety.
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| Number | Date | Country | |
|---|---|---|---|
| 20150159445 A1 | Jun 2015 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61914361 | Dec 2013 | US |
