Abstract
A method for providing a subsea template system with a tail pipe, and a subsea template system are disclosed. The subsea template system comprising a structure including a guide with an opening, and including a plurality of supports for engaging a seabed; a tail pipe being cylindrical and comprising a serrated end structure at a first (lower) end of the tail pipe, the tail pipe arranged at the opening, and the tail pipe comprising an interface for rotating and axially move the tail pipe relative to the structure. The method comprising: placing the structure and the tail pipe on the seabed; rotating and moving axially the tail pipe relative to the guide and into the seabed; drilling with the drill string an opening for an outer conductor casing; and installing the outer conductor casing and applying cement between the outer conductor casing and the tail pipe.
Claims
1-15. (canceled)
16. A method for providing a subsea template system on a seabed, the method comprising: placing the subsea template system on the seabed, the subsea template system including: a structure including a guide with an opening for a well, the structure including a plurality of supports for engaging the seabed, a tail pipe arranged within the opening, the tail pipe being cylindrical, the tail pipe including a serrated end structure at a first end of the tail pipe; rotating and moving axially the tail pipe relative to the guide and into the seabed to remain in the sea bed; drilling an opening in the seabed, inside the tail pipe, the opening of the seabed for receiving an outer conductor casing; installing the outer conductor casing in the opening of the seabed; and applying cement between the outer conductor casing and the tail pipe.
17. The method of claim 16, wherein placing the subsea template system on the seabed comprises: installing the structure on the seabed; and installing the tail pipe into the guide of the structure.
18. The method of claim 16, wherein the subsea template system further comprises a temporary lock coupled to the guide for locking the tail pipe relative to the guide.
19. The method of claim 18, wherein placing the subsea template system on the seabed comprises: locking the tail pipe to the guide with the temporary lock; installing the structure on the seabed; and releasing the temporary lock.
20. The method of claim 16, wherein the tail pipe further comprises an interface for rotating and axially move the tail pipe relative to the structure.
21. The method of claim 20, wherein rotating and moving axially the tail pipe relative to the guide and into the seabed to remain in the seabed comprises: lowering and connecting a drill string to the interface; and rotating the drill string and thereby the rotating the tail pipe while applying weight on the tail pipe to move the tail pipe axially relative to the structure.
22. The method of claim 16, wherein the tail pipe further comprises an interface for rotating and axially move the tail pipe relative to the structure.
23. The method of claim 22, wherein rotating and moving axially the tail pipe relative to the guide and into the seabed to remain in the seabed comprises: installing a dedicated tool on a drill string for connecting the drill string to the interface.
24. The method of claim 16, wherein the subsea template system further comprises a stop defined by the guide for restricting axial downward movement of the tail pipe relative to the structure.
25. The method of claim 24, further comprising rotating and moving axially the tail pipe until the stop restricts the axial movement of the tail pipe relative to the structure.
26. The method of claim 16, wherein the guide comprises a first guide for the tail pipe and a second guide for the conductor casing.
27. The method of claim 26, further comprising: rotating and moving axially the tail pipe relative to the guide while guiding the tail pipe with the first guide, and installing the outer conductor casing while guiding the conductor casing with the second guide.
28. A subsea template system comprising: a structure including a guide with an opening for a well, the guide including a first guide for the tail pipe and a second guide for an outer conductor casing, the guide including a visual indicator for determining an end position for the tail pipe, the structure including a plurality of supports for engaging a seabed; and a tail pipe arranged within the opening, the tail pipe being cylindrical, the tail pipe including a serrated end structure at a first end of the tail pipe.
29. The subsea template system of claim 28, wherein the tail pipe further comprises a stop for restricting axial movement of the tail pipe relative to the structure, the stop being a flange for engaging a landing shoulder of the guide.
30. The subsea template system of claim 28, wherein the tail pipe further comprises a stop for restricting axial movement of the tail pipe relative to the structure, the stop being a snap ring interacting with a groove of the guide.
31. The subsea template system of claim 28, wherein the tail pipe further comprises an interface for rotating an axially move the tail pipe relative to the structure, and wherein the interface is connectable to a drill string.
32. The subsea template system of claim 31, wherein the interface is connectable to a drive system coupled to the structure, the drive system configured for rotating and moving axially the tail pipe into the seabed.
33. The subsea template system of claim 28, further comprising a temporary lock coupled to the guide for locking the tail pipe relative to the guide.
34. The subsea template system of claim 28, wherein the first guide for the tail pipe is removable.
35. The subsea template system of claim 28, wherein the first guide for the tail pipe has a inner diameter smaller than the second guide for the outer conductor casing.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The accompanying drawings illustrate presently exemplary embodiments of the disclosure and serve to explain, by way of example, the principles of the disclosure.
[0012] FIG. 1 is a diagrammatic illustration of a method for providing a subsea template system with a tail pipe according to an example embodiment of the disclosure;
[0013] FIG. 2 is a diagrammatic illustration of a subsea template system according to an example embodiment of the disclosure;
[0014] FIG. 3 is a diagrammatic illustration of a part of the subsea template system according to an example embodiment of the disclosure;
[0015] FIG. 4 is a diagrammatic illustration of a part of the subsea template system according to an example embodiment of the disclosure;
[0016] FIG. 5 is a diagrammatic illustration of a part of the subsea template system according to an example embodiment of the disclosure; and
[0017] FIG. 6 is a diagrammatic illustration of the subsea template system according to an example embodiment of the disclosure.
DETAILED DESCRIPTION
[0018] FIG. 1 illustrates a method for providing a subsea template system with a tail pipe 200 according to an example embodiment of the disclosure. FIGS. 2 to 6 illustrate a subsea template system according to an example embodiment of the disclosure. FIG. 6 illustrates also how an outer conductor casing 600 is installed inside the tail pipe 200. In embodiments, the outer conductor casing 600 is a conductor 600 or a conductor housing 600. The method described herein may use any of the embodiments of the subsea template system described herein.
[0019] Turning to FIG. 1, a method for providing a subsea template system with a tail pipe is illustrated. In embodiments, the method installs a tail pipe and an outer conductor casing. With reference to FIGS. 1 and 2, the subsea template system used in the method comprises a structure 100 and a tail pipe 200. The structure 100 comprises a guide 110 with an opening 120 for a well, and the structure 100 comprises a plurality of supports 102 for engaging a seabed 104. The tail pipe 200 is cylindrical and comprises a serrated end structure 210 at a first end 202 of the tail pipe 200. The first end 202 is the lower end 202 of the tail pipe 200, the end initially engaging the seabed 104. The tail pipe 200 is arranged in the opening 120, and the tail pipe 200 comprises an interface 400 for rotating and axially move the tail pipe 200 relative to the structure 100. More details of the subsea template system is described below.
[0020] With reference to FIG. 1, the method for providing a subsea template system with a tail pipe comprises the following steps. Placing 10 the structure 100 and the tail pipe 200 on the seabed 104; rotating 20 and moving axially the tail pipe 200 relative to the guide 110 and into the seabed 104 to remain in the seabed 104; drilling 30 with a drill string 500 an opening in the seabed 104, inside the tail pipe 200, for an outer conductor casing 600; and installing 40 the outer conductor casing 600 and applying cement between the outer conductor casing 600 and the tail pipe 200. In embodiments, the outer conductor casing 600 is a conductor 600 or a conductor housing 600.
[0021] According to one embodiment, and as illustrated in FIGS. 2 to 6, the tail pipe 200 is a tube, a metal cylinder, with a serrated end structure 210. In embodiments, the serrated end structure 210 are teeth, i.e., cutting formations, that assist the tail pipe 200 to cut its way into the seabed 104. The tail pipe 200 may be used initially before starting to drill the well. The tail pipe 200 herein described is not a tail pipe under a production packer. The tail pipe 200 is rotated and moved axially into the seabed 104 several meters to remain permanent for the lifetime of the well. In some situations, only a portion of the tail pipe 200 is drilled into the seabed 104, however, in some instances, the tail pipe 200 is drilled completely, all the way, until its stop 220, into the seabed 104. To determine that the tail pipe 200 has been entered completely into the seabed, the guide 110 comprises a means for determining an end position for the tail pipe 200.
[0022] As illustrated by FIG. 1, the method step of placing the structure 100 and the tail pipe 200 on the seabed further comprises installing 11 the structure 100 on the seabed 104, and subsequently installing 12 the tail pipe 200 into the guide 110 of the structure 100. Thus, in embodiments, the structure 100 is first placed onto the seabed 104 and then the tail pipe 200 is subsequently lowered into the guide 110 of the structure 100.
[0023] As illustrated by FIGS. 1 and 2, for an embodiment of the method for providing a subsea template system with a tail pipe 200, the subsea template system further comprises a temporary lock 300 for locking the tail pipe 200 relative to the guide 110. The step of placing the structure 100 and the tail pipe 200 on the seabed 104 then comprises locking 13 the tail pipe 200 to the guide 110 with the temporary lock 300; installing 14 the structure 110 on a sea bottom; and releasing 15 the temporary lock 300. In embodiments, the tail pipe 200 is locked, held firmly in place, inside the guide 110 as the structure 100 and the tail pipe 200 are placed on the seabed 104. In a further embodiment, the tail pipe 200 is locked in an upper position relative to the guide 110. Once the structure 100 and the tail pipe 200 are on the seabed 104, then the tail pipe 200 may be unlocked so that the tail pipe 200 can be moved into the seabed 104.
[0024] As illustrated by FIGS. 1 and 4, for an embodiment of the method for providing a subsea template system with a tail pipe 200, the tail pipe 200 further comprises an interface 400 for rotating 20 and axially move the tail pipe 200 relative to the structure 100. In embodiments, the step of rotating 20 and moving axially the tail pipe 200 relative to the guide 110 and into the seabed 104 to remain in the seabed comprises lowering 21 and connecting a tool 500, for example a drill string 500, to the interface 400; and rotating 22 the tool 500, such as for example a drill string 500, and thereby rotating the tail pipe 200, while applying weight on the tail pipe 200 to move the tail pipe 200 axially relative to the structure 100. In embodiments, the interface 400 is adapted to receive a drill tool on the drill string 500. Once the tail pipe 200 has been installed in the seabed 104, the same tool may be used to drill the opening inside the tail pipe 200. In this way, one saves having to retrieve and deploy the drilling string 500.
[0025] As illustrated by FIGS. 1 and 4, for an embodiment of the method for providing a subsea template system with a tail pipe 200, the tail pipe 200 further comprises an interface 400 for rotating 20 and axially move the tail pipe 200 relative to the structure 100. In embodiments, the step of rotating 20 and moving axially the tail pipe 200 relative to the guide 110 and into the seabed 104 to remain in the seabed 104 comprises installing 23 a dedicated tool 510 on a drill string 500 for connecting the drill string 500 to the interface 400. In embodiments, a drill string 500 is used for driving the tail pipe 200 into the seabed 104.
[0026] As illustrated by FIGS. 1 and 4, for an embodiment of the method for providing a subsea template system with a tail pipe 200, the subsea template system further comprises a stop 220 restricting axial downward movement of the tail pipe 200 relative to the structure 100. In embodiments, the step of rotating 20 and moving axially the tail pipe 200 relative to the guide 110 and into the seabed 104 to remain in the seabed 104 comprises rotating 24 and moving axially the tail pipe 200 until the stop 220 restricts the axial move of the tail pipe 200 relative to the structure 100. In embodiments, the tail pipe 200 is permited to move upwards freely, but the stop 220 prevents the tail pipe 200 from separating from the guide 110. In embodiments, the stop 220 is used for determining an end position for the tail pipe 200 and may be a shoulder 150, a snap ring system, a visual indication, or other means.
[0027] For example, the axial move of the tail pipe 200 relative to the structure 100 is stopped by the use of a flange 230 on the tail pipe 200 engaging a landing shoulder 150 arranged in the relative lower end of the guide 110, as best illustrated in FIG. 5. When the flange 230 engages the shoulder 150, it can be determined that the end position has been reached. In another example, the tail pipe 200 includes a snap ring that is flexible so that it can snap into a groove on the guide 110, or the other way around. When the snap ring snaps into the groove, it can be determined that the end position of the tail pipe 200 has been reached. In another example, the means for determining an end position is a visual indicator, such as a scale, or a meter, that shows how much of the tail pipe 200 has been lowered relative to the guide 110. Such a scale or a meter can indicate and determine that the end position of the tail pipe 200 has been reached.
[0028] As illustrated by FIGS. 1 and 6, for an embodiment of the method for providing a subsea template system with a tail pipe 200, the guide 110 comprises a first guide 130 for the tail pipe 200, and a second guide 140 for the conductor casing 600. In embodiments, the outer conductor casing 600 is a conductor 600 or a conductor housing 600. In embodiments, the method further comprises rotating and moving axially the tail pipe 200 relative to the guide 110 while guiding the tail pipe 200 with the first guide 130, and installing the outer conductor casing 600 while guiding the conductor casing 600 with the second guide 140. In one embodiment, the guiding of the tail pipe 200 is done with only the first guide 130, and the guiding of the conductor casing 600 is done with only the second guide 140. By providing and guiding the tail pipe 200 using the first guide 130, and providing and guiding the outer conductor casing 600 using the second guide 140, it is possible to accurately and efficiently install the tail pipe 200 and the conductor 600, the outer conductor casing 600, into the seabed 104.
[0029] With reference to FIGS. 2 to 6, a subsea template system is disclosed. The subsea template system comprises a structure 100 and a tail pipe 200. The structure 100 comprises a guide 110, the guide 110 comprising an opening 120 for a well. The structure 100 comprises a plurality of supports 102 for engaging a seabed 104. The tail pipe 200 is substantially cylindrical and comprises a serrated end structure 210 at a first end 202, a first lower end 202, of the tail pipe 200. The tail pipe 200 is arranged in the opening 120 of the guide 110. The tail pipe 200 comprises an interface 400 for rotating and axially move the tail pipe 200 relative to the structure 100. The guide 110 comprises a first guide 130 for the tail pipe 200; a second guide 140 for an outer conductor casing 600; and means for determining an end position for the tail pipe 200.
[0030] According to one embodiment, the structure 100 comprises one, two, three, or four supports 102 for engaging the seabed 104. In embodiments, the structure 100 includes the guide 110 in a central position where the well is going to be, and the structure 100 comprises radial arms such that each arm stretches from the guide 110 substantially parallel to the seabed 104, in a horizontal direction, to one support 102. In embodiments, the guide 110 is a hollow cylinder into which the tail pipe 200 and other piping, such as the outer conductor casing 600, may be guided. In embodiments, the guide 110 is arranged, in some instances in a solid manner, in the central position of the structure 100, perpendicular to the radial arms, opening up towards the well. In embodiments, the structure 100 comprises a plurality of guide rod receptacles. In one embodiment, the receptacles are used for installing guide rods onto the structure 100. In another embodiment, the guide rods are used for installing a blow out preventer, BOP, onto the wellhead. In embodiments, the guide rods are attached to the structure 100 by being inserted and locked into the receptacles. According to one embodiment, the tail pipe 200 is a hollow cylinder, a metal cylinder, with a serrated end structure 210. In embodiments, the serrated end structure 210 are teeth, cutting formations, that assist the tail pipe 200 to cut its way into the seabed. This allows the tail pipe to cut through even a hard seabed. In some embodiments, the tail pipe 200 is used initially before starting to drill the well. The tail pipe 200 herein described is not a tail pipe under a production packer. The tail pipe 200 is inserted into the ground to remain in the ground during the lifetime of the well, and thereafter if desired. In embodiments, the tail pipe 200 is several meters long, for example over 6 meters long. In some embodiments, once the tail pipe 200 is installed, an opening is drilled into the seabed inside the tail pipe, and subsequently a conductor 600, an outer conductor casing 600, is installed inside the tail pipe 200. In embodiments, the conductor 600 is cemented in place by injecting cement between the inside of the tail pipe 200 and the outside of the outer conductor casing 600. This reduces the amount of cement or drill cuttings that may escape into the environment.
[0031] As may be taken best from FIGS. 2 to 6, in some embodiments, the first guide 130 is separate from the second guide 140. In embodiments, the guides are hollow cylinders. In embodiments, the first guide 130, for the tail pipe 200, comprises two guides 130: one guide 130 arranged in the upper part of the guide 110, and one guide 130 arranged in the lower part of the guide 110. In embodiments, the landing shoulder 150 operates and functions as the guide 130 in the lower part of the guide 110. In embodiments, the one guide 130 arranged in the upper part of the guide 110 is removably arranged on the guide 110. This allows the upper guide to be used for guiding the tail pipe 200, then be removed so that an outer conductor casing may use a second guide 140 with a larger diameter. In embodiments, the second guide 140, for the outer conductor casing 600, comprises two guides 140: one guide 140 arranged in the upper part of the guide 110 and one guide 140 arranged in the lower part of the guide 110. This arrangement is advantageous as it allows the guide 110 to guide the tail pipe 200 and the outer conductor casing 600 in one and the same guide 110. In embodiments, the guide 110 is a well slot.
[0032] With reference to FIGS. 2, 4, and 5, and according to an embodiment, the tail pipe 200 further comprises a stop 220 restricting axial movement of the tail pipe 200 relative to the structure 100. In embodiments, the stop 220 comprises a flange 230 on the tail pipe 200 for engaging a landing shoulder 150 arranged in the relative lower end of the guide 110. In embodiments, the flange 230 is at the top end 204 of the tail pipe 200. In embodiments, the landing shoulder 150 is at the lower end of the guide 110. In embodiments, the flange 230 is an integral part of the tail pipe 200. In embodiments, the landing shoulder 150 is an integral part of the guide 110. In embodiments, the stop 220 gives the end position for the tail pipe 200, and this end position is below the outer conductor casing 600 interaction surfaces with the guide 110, that is below the lower guide 140 on the guide 110.
[0033] With reference to FIGS. 2, 4, and 5, and according to an embodiment, the tail pipe 200 further comprises a stop 220 restricting axial movement of the tail pipe 200 relative to the structure 100. In embodiments, the stop 220 comprises a snap ring interacting with a groove. This alternative is not illustrated in the drawings. In embodiments, the snap ring is arranged on the tail pipe 200 and the groove is arranged in the lower part of the guide 110, or opposite. In embodiments, the groove gives the end position for the tail pipe 200, and this end position is below the outer conductor casing 600 interaction surfaces with the guide 110, that is below the lower guide 140 on the guide 110.
[0034] With reference to FIG. 4, and according to an embodiment, the interface 400 is connectable to a drill string 500. In embodiments, the interface 400 is part of the tail pipe 200 and allows the drill string 500 to connect to the tail pipe 200. The drill string 500 may then rotate and axially push the tail pipe 200 into the seabed 104. In embodiments, the interface 400 is an adapter mounted onto the tail pipe 400. In embodiments, the interface 400 is means for connecting, interfacing, with the drill string 500. In embodiments, the interface 400 connects to the drill string 500 via a dedicated tool for this purpose on the drill string 500, or via a standard tool, such as a drill tool, that is connected to the drill string 500.
[0035] With reference to FIGS. 3 and 4, and according to an embodiment, the interface 400 is connectable to a drive system 170 on the structure 100. In embodiments, the drive system 170 is configured for rotating and moving axially the tail pipe 200 into the seabed 104.
[0036] With reference to FIG. 2, and according to an embodiment, the subsea template system further comprises a temporary lock 300 for locking the tail pipe 200 relative to the guide 110. This temporary lock 300 is used when placing 10 the structure 100 and the tail pipe 200 onto the seabed 104. During the placing 10, the temporary lock 300 is locked so that the tail pipe 200 is held firmly by the guide 110. Once placed, the temporary lock 300 may be unlocked so that the tail pipe 200 can be further moved into the seabed. The locked position is illustrated in FIG. 2, wherein the first lower end 202 is closer to the guide 110 than the second higher end 204 of the tail pipe 200.
[0037] According to one embodiment, a further separate lock is used to lock the tail pipe 200 relative to the guide 110 once the tail pipe 200 has been installed. The lock prevents the tail pipe 200 from rotating during drilling and also prevents axial movement of the tail pipe 200.
[0038] With reference to FIGS. 2 to 6, and according to an embodiment, the means for determining an end position for the tail pipe 200 may be a shoulder 150, a snap ring system, a visual indication, or other means. For example, in an embodiment, the guide 110 has a shoulder 150 and the tail pipe 200 a flange 230 for engaging the shoulder 150, as best illustrated in FIG. 5. When the flange 230 engages the shoulder 150, it can be determined that the end position has been reached. In another example, in an embodiment, the tail pipe 200 has a snap ring that is flexible so that it can snap into a groove on the guide 110, or the other way around. When the snap ring snaps into the groove, it can be determined that the end position of the tail pipe 200 has been reached. In another example, in an embodiment, the means for determining an end position is a visual indicator, such as a scale, or a meter, showing how much of the tail pipe 200 has been lowered relative to the guide 110. Such a scale or a meter can indicate and determine that the end position of the tail pipe 200 has been reached.
[0039] With reference to FIGS. 2 to 6, and according to an embodiment, the first guide 130 for the tail pipe 200 is removable; and/or the first guide 130 for the tail pipe 200 has a smaller inner diameter than the second guide 140 for the outer conductor casing 600. In an embodiment, the upper first guide 130 may be removed from the guide 110 once the tail pipe 200 has been installed. In combination with this, or as an alternative, in an embodiment, the first guide 130 for the tail pipe 200 has a first inner diameter that contacts and guides the tail pipe 200. In embodiments, the second guide 140 for the outer conductor casing 600 has a second inner diameter that contacts and guides the outer conductor casing 600. In embodiments, the first inner diameter is larger than the second inner diameter.
[0040] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using the subsea template system and performing the methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
