Offshore drilling and a configurable support structure for the same

Abstract

Without limitation, embodiments of the present invention relates to an offshore wellhead platform (100), the offshore wellhead platform (100) comprising a configurable support structure (200) for supporting upper parts of a plurality of conductors (210) through which one or more well processing tasks can be performed, wherein the configurable support structure (200) further provides a first position (150) and a second position (160) for the conductors (210), and the offshore wellhead platform (100) allows movement of an upper part of a conductor (210) between its first (150) and second position (160). In this way, efficiency when processing a plurality of wells is provided since repositioning of the well center is not needed or needed significantly less. Effectively, the wells are brought to the well center so-to-speak instead of the well center needing to be moved to each well.

Claims

1. An offshore bottom supported wellhead platform comprising: a configurable support structure for supporting at least respective upper parts of two or more conductors, the upper part of each conductor comprising an upper end through which one or more well processing tasks can be performed, the configurable support structure including support structures extending to the seabed such that the wellhead platform is supported by the seabed, wherein the offshore bottom supported wellhead platform allows movement of the upper part of each of the two or more conductors between a first and a second position of each of the two or more conductors, the first and second positions of a conductor corresponding to first and second positions, respectively, of the upper end of said conductor, wherein the configurable support structure supports the two or more conductors at least at said first position, where the second positions of a plurality of said two or more conductors are a shared second position corresponding to a shared second position of the upper ends of the plurality of said two or more conductors, at which each of said plurality of conductors may be selectively placed, wherein the offshore bottom supported wellhead platform allows performance, by a well processing station, through a well center of said well processing station, without lateral displacement of the well processing station or its well center, of a well processing task through the upper end of a conductor of said plurality of said two or more conductors, when positioned at said shared second position, and a subsequent well processing task through the upper part of another conductor of said plurality of said two or more conductors, when subsequently positioned at said shared second position; and wherein, when one of said two or more conductors is the shared second position, the configurable support structure is adapted to apply one or more counter forces to one or more other conductors of said two or more conductors in a direction opposite the movement of the one of said two or more conductors between said first position and said second positions to relieve stress to the wellhead platform.

2. The offshore bottom supported wellhead platform according to claim 1, wherein said configurable support structure provides said first position and second position for each of the two or more conductors.

3. The offshore bottom supported wellhead platform according to claim 2, wherein said configurable support structure supports each conductor when in the shared second position, and supports each conductor when moving the upper part between said first and said shared second position of the conductor.

4. The offshore bottom supported wellhead platform according to claim 1, wherein the first positions of the two or more conductors are at least one member selected from the group consisting of a parking, a storage, an injection, a well intervention, and a production position.

5. The offshore bottom supported wellhead platform according to claim 1, wherein at least one of the offshore bottom supported wellhead platform comprises at least one mechanism for moving the upper part of a conductor between its first position and its second position; and the offshore bottom supported wellhead platform allows at least one external device to move an upper part of a conductor between its first position and its second position.

6. The offshore bottom supported wellhead platform according to claim 1, wherein said plurality of said two or more conductors having a shared second position form a first cluster and wherein the configurable support structure is further arranged to support a second plurality of said two or more conductors having another shared second position thereby forming a second cluster for which the offshore bottom supported wellhead platform allows moving an upper part of a conductor from each of a plurality of first positions of the upper ends of the second plurality of said two or more conductors of the second cluster to the another shared second position of respective upper ends.

7. The offshore bottom supported wellhead platform according to claim 1, wherein the first positions and the shared second position of the upper ends of the plurality of said two or more conductors are provided according to an arrangement wherein the shared second position of the upper ends is provided substantially centrally and at least one first position of the upper ends is provided at a first side of the shared second position of the upper ends and at least one other first position of the upper ends is provided at a second opposing side of the shared second position of the upper ends.

8. The offshore bottom supported wellhead platform according to claim 1, wherein the configurable support structure is configured such that the shared second position of the upper ends may be selectively chosen within a predetermined working center zone or at least within a predetermined offset zone within said working center zone.

9. The offshore bottom supported wellhead platform according to claim 1, comprising one or more support elements configured to maintain the conductors at fixed respective positions at or near the seabed.

10. The offshore bottom supported wellhead platform according to claim 1, comprising one or more support elements each configured to engage a conductor at a position along the length of the conductor above the seabed and to restrict lateral movement of the conductor relative to the support elements.

11. The offshore bottom supported wellhead platform according to claim 10, wherein at least of said one or more support elements is movably attached to a part of the wellhead platform.

12. The offshore bottom supported wellhead platform according to claim 11, comprising a mechanism for imparting movement on at least one of the movable support elements.

13. The offshore bottom supported wellhead platform according to claim 10, comprising two or more support elements configured to engage a first conductor at respective positions along the length of the first conductor and to restrict lateral movement of the conductor relative to the support elements, wherein the support elements operable to engage the first conductor comprise a lowermost support element at or near the seabed and an uppermost support element proximal to the upper end of the first conductor; wherein the lowermost support element is adapted to fix the position of the conductor relative to the seabed and/or relative to a main structure of the wellhead platform; and wherein the uppermost support element is a movable support element.

14. The offshore bottom supported wellhead platform according to claim 13, wherein the two or more support elements operable to engage the first conductor comprise two cooperating support elements arranged to apply oppositely oriented, lateral forces at respective positions along the length of the first conductor.

15. The offshore bottom supported wellhead platform according to claim 1, wherein the configurable support structure comprises one or more support elements operable to support each conductor at its first position; wherein the configurable support structure allows the upper part of each conductor to be moved at least from the shared second position to the first position for said conductor; and wherein the wellhead platform and the configuration of any other conductor supported by the wellhead platform as defined by a corresponding support configuration of the wellhead platform allow such movement at least during establishing of the wells.

16. The offshore bottom supported wellhead platform according to claim 1, wherein the configurable support structure comprises one or more support elements for engaging with the conductors and for transferring forces due to bending of the conductors at the first and/or second position to the wellhead platform and thereby locking the conductors in the respective position.

17. The offshore bottom supported wellhead platform according to claim 1, wherein the configurable support structure comprises support elements at two or more elevations operable to work in collaboration to control the curve of a conductor and the position of the upper end of the conductor.

18. The offshore bottom supported wellhead platform according to claim 1, wherein the configurable support structure is configured to provide a compensation position at least for some of the conductors.

19. The offshore bottom supported wellhead platform according to claim 18, wherein the configurable support structure allows movement of the upper end of at least some of the conductors to a compensation position different from the first and second positions.

20. The offshore bottom supported wellhead platform according to claim 1, wherein the wellhead platform comprises at least one support element adapted to at least partially relieve the wellhead platform of stress when a first conductor is moved from its first position to its second position by moving at least one other conductor to a compensation position when the first conductor is moved to its second position.

21. The offshore bottom supported wellhead platform according to claim 20, wherein the compensation position of the at least one other conductor is different from its first and second positions.

22. The offshore bottom supported wellhead platform as recited in claim 1, wherein the configurable support structure of the offshore wellhead platform is located above sea surface level.

23. A method of constructing and/or processing one or more offshore surface-wells, the method comprising constructing and/or processing an offshore surface-well through a well center of a well processing station, the surface-well comprising a conductor having an upper part including an upper end, and said method comprising the steps of: providing a bottom supported configurable support structure for the well processing station, the configurable support structure including support structures extending to the seabed and supporting a wellhead platform with the configurable support structure; constructing and/or processing a first surface-well through the upper end of the conductor at a second position, moving the upper part of the conductor to a first position of the conductor, producing from or injecting into the first surface-well through the upper end of the conductor at the first position; and the method further comprises applying one or more counter forces to one or more other conductors in a direction opposite the movement of the conductor between the first position and the second position by at least one support element when moving the conductor from the first position to the second position, the one or more counter forces reducing the impact of a movement force on a main structure supported by the configurable support structure, where the movement force is a force acting on the conductor due to the conductor being moved between the first and the second position.

24. The method according to claim 23, the method comprising applying one or more counter forces by moving at least one other conductor to one or more compensation positions when the conductor is moved to its second position.

25. A method of constructing and/or processing one or more offshore surface-wells, wherein the method comprises progressing a plurality of surface-wells towards completion by: providing a bottom supported configurable support structure for a wellhead platform, the configurable support structure including support structures extending to the seabed and supporting a wellhead platform with the configurable support structure; moving an upper part, of a selected one conductor of a surface-well, from a first position to a shared second position of the upper end and carrying out one or more well constructing and/or well processing tasks through the upper end of the selected one conductor to at least partly complete the surface-well of the selected one conductor, moving the upper part of the selected one conductor from the shared second position of the upper end to a first position of the upper end after at least partly completing the surface-well, and repeating these steps for one or more additional conductors, wherein the method further comprises applying one or more counter forces to one or more other conductors in a direction opposite the movement of the selected one conductor between the first position and the second position by at least one support element when moving the selected one conductor from the first position to the shared second position, the one or more counter forces reducing the impact of a movement force on a main structure supported by the configurable support structure, where the movement force is a force acting on the selected on conductor due to the selected one conductor being moved between the first and the second shared position.

26. The method according to claim 25, comprising at least one of: installing a least a part of the conductors at the respective first positions; wherein installing comprises bringing the conductor into engagement with at least some support elements of the configurable support structure of the wellhead platform; installing a least a part of the conductors at the second position; wherein installing comprises bringing the conductor into engagement with at least some support elements of the configurable support structure of a wellhead platform; and moving the installed part of the conductor to a first position; and pre-installing a lower part of the conductors at a wellhead platform, prior to positioning the wellhead platform at an offshore site; wherein installing comprises bringing the conductor into engagement with at least some support elements of the configurable support structure of the wellhead platform; and installing a remaining part of the conductors after at least a part of the wellhead platform is positioned at the offshore site.

27. The method according to claim 25, the method comprising applying one or more counter forces by moving at least one other conductor to one or more compensation positions when the selected one conductor is moved to its second shared position.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 schematically illustrates a part of an embodiment of an offshore wellhead platform according to the present invention together with a surface-well;

(2) FIG. 2 schematically illustrates a top view of an exemplary embodiment of at least a part of a configurable support structure;

(3) FIG. 3 schematically illustrates a front view of an exemplary embodiment of an offshore wellhead platform and an offshore well processing system;

(4) FIGS. 4a-4m schematically illustrates a number of different exemplary configurations of first and second positions in a plane or at deck; and

(5) FIG. 5 schematically illustrates at least a part of a configurable support structure together with an appropriate working center zone;

(6) FIGS. 6a and 6b schematically illustrate at least a part of a configurable support structure after conductors have been installed at first positions located in a working center zone and after installation of x-mas trees on these conductors, respectively;

(7) FIG. 7 schematically illustrates at least a part of a configurable support structure with a working center position at two different positions;

(8) FIG. 8a schematically illustrates a front view of the offshore wellhead platform and an offshore well processing system.

(9) FIG. 8b schematically illustrates a front view of the offshore wellhead platform and an offshore well processing system.

(10) FIG. 9 schematically illustrates side force compensation according to one aspect of the present invention;

(11) FIG. 10 schematically illustrates one exemplary embodiment of a configurable support structure facilitating side force compensation e.g. as illustrated in FIG. 9;

(12) FIGS. 11a and 11b schematically illustrate side and top (or bottom) views of an exemplary conductor guide according to one aspect of the present invention;

(13) FIGS. 12a and 12b schematically illustrate a number of conductor guides, such as the ones shown in FIGS. 11a and 11b, and a number of restriction elements according to some embodiments;

(14) FIGS. 13a-13c schematically illustrates a conductor guide, such as the ones shown in FIGS. 11a and 11b, and a restriction element according to some alternative embodiments;

(15) FIG. 14 schematically illustrates a conductor guide, such as the ones shown in FIGS. 11a and 11b, and a restriction element according to yet other alternative embodiments;

(16) FIG. 15 schematically illustrates a conductor guide, such as the ones shown in FIGS. 11a and 11b, and conductor positioning elements according to some embodiments;

(17) FIG. 16 schematically illustrates a conductor guide, such as the ones shown in FIGS. 11a and 11b, and conductor positioning elements according to some alternatives embodiments;

(18) FIG. 17 schematically illustrates a configurable support structure and an arrangement for moving a conductor;

(19) FIG. 18 schematically illustrates a configurable support structure and an alternative arrangement for moving a conductor;

(20) FIG. 19 schematically illustrates a number of conductor separation elements;

(21) FIG. 20 schematically illustrates one alternative conductor separation element;

(22) FIG. 21 schematically illustrates a conductor running from the seabed to above the sea-level together with indications of locations of various support elements;

(23) FIG. 22 schematically illustrates an exemplary double-conductor guide according to one aspect of the present invention particularly suited for a seabed well template;

(24) FIG. 23 schematically illustrates another embodiment of a suitable mechanism for moving an upper part of a conductor between its first position and its second position and a locking mechanism for securing an upper part of a conductor at is second position;

(25) FIG. 24 schematically illustrates a configurable support structure and an alternative arrangement for moving a conductor;

(26) FIGS. 25a and 25b schematically illustrates another embodiment of a configurable support structure;

(27) FIGS. 26a-d schematically illustrates another embodiment of an offshore wellhead platform with conductors in their respective first positions;

(28) FIGS. 27a-d schematically illustrates the embodiment of an offshore wellhead platform of FIGS. 26a-d but with two conductors in their respective second positions and FIG. 27e illustrates these two conductors reverted to the first positions of the upper ends; FIGS. 28a-c schematically illustrate different embodiments of moving mechanisms for use with the embodiment of FIGS. 26a-d and 27a-d;

(29) FIGS. 29a-c schematically illustrate embodiments of support elements of a configurable support structure;

(30) FIG. 30 schematically illustrates an embodiment of a coupling element for coupling a wellhead to an x-mas tree.

DETAILED DESCRIPTION

(31) Various aspects and embodiments of offshore wellhead platforms, methods of constructing and/or processing one or more offshore surface-wells, offshore well processing systems for performing one or more well processing tasks on a plurality of surface-wells, and support elements for such offshore well processing systems as disclosed herein will now be described with reference to the figures.

(32) In the following, the invention is exemplified in relation to various configurations of first and second positions of conductors in relation to a plane such as a wellhead deck, cellar deck or wellhead access deck (see e.g. FIGS. 2, 4-7, and 8a). As explained above, the first and second positions of a conductor correspond to respective positions of the upper end of the conductor, which are relevant in relation to i) aligning with a well center, ii) sharing a second position, and iii) relative positions in a cluster. Accordingly, unless otherwise clear, the first and second positions shown in the plane may be taken to refer to i) the respective upper ends or ii) a cross section of the upper part of respective conductors in that plane. A coinciding position of two or more conductors also provides a coinciding position of the respective upper ends of the two or more conductors. In some embodiments, this plane is the wellhead deck, cellar deck or a well access platform deck or a plane relatively close to the upper ends of the conductors. In some embodiments, a cross section taken at two or more decks showing the cross section of the conductors extending through these decks and/the opening(s) for supporting the conductors and the movement of their upper parts will be substantially identical when the decks are e.g. a cellar deck and a wellhead access deck or wellhead deck.

(33) It is noted that, in general, a conductor said to have a position or a configurable support structure comprising a position, corresponds to the configurable support structure being arranged to support a conductor in this position and/or the wellhead platform (and configurable support structure) being arranged to allow movement between that position and another position.

(34) The shown figures are schematic representations for which reason the configuration of the different structures as well as their relative dimensions are intended to serve illustrative purposes only.

(35) Some of the different components are only disclosed in relation to a single embodiment of the invention, but is meant to be included in the other embodiments without further explanation.

(36) FIG. 1 schematically illustrates a part of an embodiment of an offshore wellhead platform according to the present invention together with a surface-well.

(37) Shown is a part of an offshore wellhead platform, e.g. a part of a deck forming part of a configurable support structure e.g. a wellhead deck or cellar deck, being located above a given water level 110 and receiving and/or supporting an upper part of a plurality of surface-wells 300, e.g. receiving or/and supporting at least the surface-well wellheads.

(38) By surface-well is to be understood that the wellhead of a well is located above the water level 110. Surface-wells are opposed to sub-sea wells, subsea trees, wet trees, etc. It is noted, that only a single well 300 is shown in FIG. 1 (in three different positions as will be explained further in the following) but practically a plurality of surface-wells 300 will typically be supported by a wellhead platform.

(39) In some embodiments, the offshore wellhead platform may be part of an offshore facility or be used in connection with such one, e.g. with facilities to extract and process hydrocarbons or other liquids and/or gasses, inject liquid(s) or gas(ses) in one or more wells, and e.g. to temporarily store product until it can be brought to shore.

(40) The surface-wells 300 are connected to one or more offshore reservoirs (not shown) located below a seabed 120.

(41) The offshore wellhead platform comprises a configurable support structure 200 for supporting at least an upper part of a plurality of conductors 210 (one conductor having one upper part) where an upper part comprises an upper end through which one or more well processing tasks can be performed. A conductor 210 forms part of a surface-well 300.

(42) The conductors 210—when in place—extend from below the seabed 120 to the offshore wellhead platform above the water level 110. As generally know in the art of contstructing hydrocarbon well, inside the conductors 210, one or more conduits (typically casings) of decreasing size (see e.g. 210, 215, and 220 in FIG. 2) is/are located when a well is completed; typically the conduits in turn extending further and sometimes the smallest used or necessary (often referred to as a productions liner or the like) even connects into an off-shore reservoir.

(43) One or more well processing tasks, such as drilling, extraction of gas or oil, injection, well intervention, etc. may be performed through one or more of the conductors 210.

(44) Traditionally, such conductors are considered rigid (at least along a substantial part of their length but often along their entire length) and once in place in the seabed 120 they are typically substantially static that during well processing tasks including eventually extraction, production, injection, well-intervention, etc. Traditionally, such conductors are often regular steel pipes or similar. As explained earlier, such conductors are commonly referred to as non-flexible conductors (even though they are flexible to a certain extent) as opposed to so-called flexible pipes that often are used in connection with deep-water or sub-sea wells or surface-wells located on a platform not being fixed to the seabed.

(45) Traditionally, the conductors may e.g. be arranged in a grid of wells or similar.

(46) Once a well is completed, it will typically have installed a production tree (also referred to as Christmas or x-mas tree) or similar on the wellhead making it ready for e.g. hydrocarbon extraction or production, injection, well intervention, or other.

(47) According to the present invention and aspects thereof, the configurable support structure 200 further provides a first position and a second position (see e.g. 150 and 160, respectively, e.g. in FIG. 2) for at least some, but e.g. all, of the plurality of conductors 210 where the offshore wellhead platform and/or the configurable support structure 200 allows movement of an upper part of a conductor 210 between its first (or a first) and its (or a) second position. The first (and second) positions may e.g. also be referred to as slots or the like.

(48) In some embodiments, and as will be explained further, the upper parts of some conductors 210 may share a number of first positions in the sense that at least the positions of the upper ends coincide, where sharing is in the sense that several conductors 210 may use a first position but one at a time, not in the sense that the upper part of several conductors 210 will be at the same first position at the same time. In some embodiments, as also will be explained further, some conductors 210 may share at least at the upper end—as more often will be the case—a second position (or share several second positions) again in the sense that a plurality of conductors 210 will not occupy one second position at the same time.

(49) The positions (first and second) may generally only have room for one conductor (and e.g. some additional space as needed allowing for safe movement).

(50) Preferably and as mentioned, the first position of a given conductor 210 is at least one member selected from the group of a parking, a storage, etc. position (that also may be used for production and/or injection and/or well-intervention and even installation of the christmas tree etc.) and the second position of the given conductor 210 is a well processing and/or drilling and/or completion and/or other intervention, etc. position. In many embodiments it will be preferable to perform drilling and general well construction in the second position while intervention may preferably be performed in the first position so that the welhead platform preferably supports access for well intervention tools to well with the upper end in the first position e.g. via hatches in one or more decks above the upper end in the first position.

(51) This enables moving an upper part of a conductor 210 from the first (parking, storage, etc.) position to a second (well processing, drilling, etc.) position when the conductor 210 is to be used as part of a well processing or drilling process and back again (or e.g. to another first position) after use giving a number of advantages as explained further throughout this description. In general the conductors are not required to start in the first position (i.e. be moved from a first position) but may e.g. begin in the second position, a position in between the first and second position or in a different first position. After a conductor 210 has been used and moved to its first position, another conductor 210 may begin at or be moved to its second position (in some embodiments being the same, i.e. shared, position for the upper ends and in other alternative embodiments being a different position for the upper end than the second position of the earlier conductor) for use. In some embodiments, a conductor 210 may—after use—be moved to another first position instead of the first position it arrived from.

(52) Shown in FIG. 1 is a surface well 300 with its upper part being at respective three different positions. The middle position (in the Figure) may e.g. be a second position of the upper ends 160 while the two other positions may e.g. be two different first positions 150.

(53) Even for embodiments, where the conductors 210 are considered relatively rigid, such as a steel pipes or the like, they are sufficiently flexible to allow for some movement of their upper parts and end, even after the well has been established through the conductor especially due to their typical length from the seabed and up. Generally, the longer the conductors are above the seabed, the less angular deviation from vertical is generally needed.

(54) In some embodiments, it is faster (and simpler) to move an upper part of well (by moving the upper part of its conductor), e.g. wellhead, casings inside this part of the conductor and x-mas tree installed on the wellhead, between a first position and a second position than repositioning the well center by skidding, moving a cantilever, etc.

(55) The time saving is applicable to processing multiple wells both in a more traditional manner (completing one well at a time) and as batch-drilling (completing the same task(s) and/or sub-task(s) for all or at least some or several wells in turn before moving to the next task(s) and/or sub-task(s)).

(56) Furthermore, as specialized equipment like skids, rails, cantilever are not needed or needed less they may be omitted or be of simpler design or used for other purposes.

(57) Additionally, when the wells are completed and used for production or injection or well-intervention or other they may simply be ‘parked’ at an individual first position.

(58) Once maintenance, work-over, etc. or other intervention is needed, the conductor and its associated well may simply be moved to the second position again to carry out the maintenance or work-over process(es).

(59) As another examples of a specific design of a wellhead platform and the horizontal section of the configurable support structure (e.g. at the level of the wellhead deck) comprising one centrally located shared second position and eight adjacent first positions (see e.g. FIG. 4b) with a maximum distance (e.g. center-to-center distance) between the second and each individual first position being about 2.0 meters, the smallest angular deviation needed may e.g. be about 1.3°, about 1.5°, and about 1.7° for water depths of about 70 meters, about 60 meters, and about 50 meters (or corresponding lengths of the conductors), respectively (with the only varying parameter being the water depth).

(60) Generally, for a specific design, the smallest angular deviation needed will increase with increasing maximum distance between a second and each individual first position and increase with decreasing water depth (length of the conductor).

(61) At least one suitable mechanism is provided for moving an upper part of a conductor between its first position and its second position, such as a shared second position. In general, the at least one mechanism for moving the upper part of a conductors may e.g. be located on the offshore wellhead platform or could be located externally from the wellhead platform, such as on an offshore well processing system (see e.g. 400 in FIGS. 3 and 8). The mechanism may be any suitable mechanism capable of moving (the upper part) of a conductor e.g. by pulling, pushing, etc. For example, the mechanism may be mechanical or hydraulic push or pull, a rack and pinion drive, winch-wire, or any other suitable mechanism for moving, shifting, etc. the conductor between the first and second position. The described mechanisms may be suitable for moving upper parts of two or more conductors, such as four or more, such as six or more, such as all conductors supported by the configurable support structure. Examples of suitable moving mechanisms or systems will be described in greater detail below e.g. with reference to FIGS. 17, 18, and 24 (see the conductor moving system 550).

(62) In some embodiments, the configurable support structure is arranged to support conductors forming at least one cluster (see e.g. 600 in FIGS. 4d-4h and 4k-4m), e.g. in two (see e.g. FIGS. 4d, 4f), four (see e.g. FIGS. 4e, 4g), six (see e.g. FIG. 4h), and so on. The number of groups or clusters may also be an odd number.

(63) The wellhead platform and the configurable support structure may e.g. support two (or more) second positions for use with two (or more) well centers/drilling stations that may belong to a single (same) cluster or alternatively to different clusters.

(64) In some embodiments, one or more blow-out-preventer (BOP) components or units is provided—e.g. by the wellhead platform and/or an offshore well processing system (see e.g. 400 in FIGS. 3 and 8) e.g. located on (typically inside) a cantilever (see e.g. 405 in FIG. 8)—to which one or more wells may be connected.

(65) In this way, the possibility to connect one or more wells—during well progression—to a BOP is readily provided, e.g. as an intermediate step while another well is being worked at. In some embodiments, a substantially minimum bending stress state of a conductor is at a predetermined position for the conductor that is located between the first and the second position of the upper end of the conductor (e.g. closer towards the second position or alternatively substantially midway), or located substantially at the second position of the conductor, located substantially at the first position of the conductor.

(66) An advantage of the embodiments where the substantially minimum bending stress state of a conductor is at a predetermined position for the given conductor that is located substantially at or closer to a first position in relation to production or injection or well-intervention, etc. is that the wells will be in the first positions for a much longer time unless something unexpected happens thereby requiring maintenance or work-over or other intervention.

(67) An advantage of the embodiments where the substantially minimum bending stress state of a conductor is at a position for the conductor that is located substantially at or closer towards the second position of the upper end of the conductor is that the conductor likely will be deflected the least or less at that position thereby facilitating drilling or well processing tasks to be performed through the upper part of the conductor. Furthermore, it will comparatively require less applied force to move the upper part of the conductor to a second position but then comparatively require more applied force to move an upper part of the conductor to a first position.

(68) An advantage of the embodiments where the substantially minimum bending stress state of a conductor is at a position for the conductor that is located substantially midway between the first and the second position of the upper end of the conductor is that an overall maximum reach for a bending stress level is obtained. I.e. the distance between the first and the second position may be greater for the bending stress level compared to other states with the minimum bending stress state being closer to either the first or the second position of the upper end.

(69) As mentioned above, the positions of the minimum bending stress may change as the well is constructed and the above consideration may be for the conductor and alone and/or for the conductor with the casings and other components of the well installed.

(70) The conductors may e.g. be secured below the water level to the structure of the offshore wellhead platform as generally known and e.g. as described in U.S. Pat. No. 3,670,507.

(71) In certain embodiments, the respective upper part of the conductors comprises a part or segment made of a more flexible material (than what the rest of the conductor primarily is made of, e.g. steel) and/or being flexible in another manner. Flexibility may e.g. be provided by varying the properties and/or geometry of the conductor at certain parts. This may reduce the extent of moving the upper part of a conductor.

(72) In some embodiments, the conductors are used at water depths e.g. being selected from about 30 meters to about 300 meters or from about 30 meters to about 150 meters. Various aspects and embodiments of a method of processing or drilling one or more offshore surface-wells using a configurable support structure 200 and embodiments thereof as just described are explained in connection with FIG. 2.

(73) FIG. 2 schematically illustrates a top view of an exemplary embodiment of a part of a configurable support structure.

(74) Shown from above or below is at least a part of a configurable support structure such as the ones shown and explained in connection with FIG. 1 and throughout the present description.

(75) The configurable support structure 200 (only the relevant horizontal section is shown) provides a number, here as an example six, of first positions 150 and a number, here as an example one, of second positions 160.

(76) In each first position or slot 150 is shown one conductor 210. The conductors 210 may each comprise a smaller diameter conduit 215 and an even smaller diameter conduit 220, e.g. the production liner, as generally known. There may be an air-gap or space present at each first position or slot 150 for providing room between the conductors 210 and the configurable support structure 200. Also shown and indicated by ‘A’ is a center-to-center distance between two neighboring conductors 210 each in a first position.

(77) Further shown and indicated by ‘B’ is a center-to-center distance between a center of the second position of the upper end 160 and a center of each of the first positions of the upper ends 150. In some embodiments (and as shown), B will be substantially the same to all first positions or at least have a minimum distance for all associated first positions. However, it may also be different for at least some first positions (see e.g. FIGS. 4i-4m, 5, 6a-6b, and 7).

(78) In some embodiments, A is selected from about 0.25 meters to about 10 meters. In some embodiments, A is selected from about 0.8 meters to about 5 meters. In some embodiments, A is selected from about 1 meter to about 2.5 meters. In some embodiments, A is selected from about 0.8 meters to about 2 meters. In some embodiments, A is selected from about 1.2 meters to about 1.9 meters.

(79) In some embodiments, B is selected from about 0.25 meters to about 25 meters. In some embodiments, B is selected from about 0.5 meters to about 15 meters. In some embodiments, B is selected from about 1.5 meters to about 10 meters. In some embodiments, B is selected from about 1 meter to about 4 meters. In some embodiments, B is a value being larger than about 0.1 meters. In some embodiments, B is a value being larger than about 0.25 meters. In some embodiments, B is a value being larger than about 0.5 meters. In some embodiments, B is a value being larger than about 0.75 meters. In some embodiments, B is a value being larger than about 1 meter. In some embodiments, B is a value being larger than about 1.25 meters. In some embodiments, B is a value being larger than about 1.5 meters. In some embodiments, B is a value being larger than about 2 meters. In some embodiments, B is a value being larger than about 2.5 meters. In some embodiments, B is a value being larger than about 3 meters. In some embodiments, B is a value being larger than about 3.5 meters. In some embodiments, B is a value being larger than about 4 meters. In some embodiments, B is a value being larger than about 5 meters. In some embodiments, B is a value being larger than about 6 meters. Finally, a working center zone 250 is indicated by a central darker dashed circle. It is noted that the working center zone 250 does not form part of the configurable support structure 200 but rather is projected thereon to better illustrate its position in relation to the shared second position when used.

(80) The offshore wellhead platform comprising the configurable support structure may comprise an opening at its upper structure (e.g. at the weather deck, also sometimes called main deck, of the offshore wellhead platform) above the one or more shared second positions that more or less coincide or at least overlap with the working center zone during well construction of a well or wells at a shared second position or positions, respectively. See also FIGS. 5, 6a-6b, and 7 for examples of parts of a configurable support structure together with an appropriate working center zone.

(81) The configurable support structure may e.g. be or comprise parts that are part of a wellhead deck (also sometimes referred to as wellhead platform deck, cellar deck, etc.) of an offshore wellhead platform (see e.g. FIG. 26). As a note, production trees of completed wells may be located at a deck (sometimes referred to as the Christmas tree deck or other) located between the weather deck and the wellhead deck.

(82) As indicated by double arrows, the respective conductors 210 are movable between the first and second positions 150, 160 as explained in connection with FIG. 1 and throughout the present description.

(83) The configurable support structure may be used to carry out aspects of a method of processing or drilling one or more offshore surface-wells (see e.g. 300 in FIG. 1). In some embodiments, the method comprises constructing and/or processing multiple offshore surface-wells from a single well center by moving the upper parts of one or more conductors to and from the single working center.

(84) In some embodiments, the method comprises using at least one offshore wellhead platform as described elsewhere wherein the single working position is a shared second position.

(85) In some embodiments, the method comprises progressing a plurality of surface-wells towards completion by moving the upper part of a conductor from either (i) from a first position to a second position (ii) installing the conductor at least with the upper part in its second position or (iii) installing the conductor away from either its first or second position and moving its upper part to its second position, carrying out one or more well constructing and/or processing tasks (e.g. including sub-tasks) to complete the surface-well of the conductor and subsequently moving the upper part of the conductor to the first position of the conductor. After the well has been completed (or at least progressed towards completion as desired), the conductor is moved to a first position (e.g. the first position it came from or to another first position). Completion (at least partially) for one well may be done at one position while production (and potentially other well processing tasks) may be done for the same well at a different position. Then another conductor is moved from its first position to the shared second position and completed (or progressed as desired) and moved back to a first position (original or different). This is repeated until the desired conductors have been completed.

(86) In this way, efficiency is increased for drilling or processing a plurality of wells since repositioning of the well center is not needed or needed significantly less when completing or progressing them as desired one at a time. The conductors need not necessarily be completed or progressed to the same extent, although they often will be.

(87) It should be noted that the method and embodiments thereof may be carried out, e.g. overlapping in time, at two (or more) second positions. The specific steps, tasks, etc. and their timing carried out at different second positions may and often will be different—although they may be the same.

(88) In some alternative embodiments, the method comprises progressing a plurality of surface-wells towards completion by, at a second position of the conductor, carrying out at least one well constructing and/or processing task and/or sub-task. After the task(s) and/or sub-task(s) has/have been completed, the given conductor is moved to a first position. Then a next conductor is moved from its first position to the second position and the task(s) and/or sub-task(s) are carried out on or for the next conductor after which it is moved to a first position (original or different). This is repeated until the relevant task(s) and/or sub-task(s) has/have been carried out on the desired conductors. Once that is the case, the next task(s) and/or sub-task(s) is/are carried out on all the desired conductors. The next task(s) and/or sub-task(s) need not—but may do so—start with the same conductor as was started with for the previous task and/or sub-task. This is repeated until all desired tasks and/or sub-tasks have been carried out for all desired conductors.

(89) Again, the process and variations thereof may be carried out, e.g. overlapping in time, at two (or more) second positions (then by two or more well processing stations). The specific steps, tasks, etc. and their timing carried out at different second positions may and often will be different—although they may be the same.

(90) In this way, efficiency is increased for batch drilling or batch processing of a plurality of wells carrying out a group of one or more tasks and/or sub-tasks at a time on all the relevant conductors. The conductors need not necessarily be completed or progressed to the same extent, although they often will be.

(91) After completion (by either method or embodiments thereof), the conductors may be secured at a number of first positions for well intervention, or production phase.

(92) The configurable support structure (both the one shown in FIG. 2 and the ones shown in the other figures) may comprise one or more locking or securing mechanisms or elements (not shown; forth only referred to as securing elements).

(93) In some embodiments, at least one securing element provides securing of one or more conductors at first positions that, e.g. permanently, may lock at least one conductor in place at respective first positions, e.g. when the conductor is ready for production, injection, well-intervention, or similar. Examples of such securing elements are latches, clamps, wedges, or other securing elements.

(94) In some embodiments (e.g. in combination with one or more of the embodiments given above), at least one securing element is provided at each second position for securely maintaining a conductor in place at a respective second position during well processing, drilling, etc. Such securing elements may e.g. allow some degree of movement. Examples of such securing elements are mechanical or hydraulic push or pull, a rack and pinion drive, winch-wire, or any other suitable mechanisms for retaining, moving, shifting, etc. In some embodiments, the second position securing element may be combined with the least one mechanism for moving the upper end of a conductor between its first position and its second position.

(95) In some embodiments (e.g. in combination with one or more of the embodiments given above), the offshore wellhead platform or the configurable support structure 200 comprises a number of collision prevention or separation elements 170 e.g. one for each first position 150 where the collision prevention or separation element forms a barrier or similar between the second position(s) 160 and the first positions 150 e.g. as indicated by the dashed line 170. Preferably, the collision prevention or separation elements will shield each first position 150 from the second position(s) 160, e.g. one collision prevention or separation element for each first position 150 or one collision prevention or separation element covering more or all first positions 150. Examples of such collision prevention elements are structural elements, beams, cushion or dampening elements, etc. One or more collision prevention or separation elements may e.g. be combined with one or more second position securing elements and/or the one securing element(s) providing securing of one or more conductors at first positions.

(96) Such configurable support structures and methods as described above function particularly well together with embodiments of an offshore well processing system (see e.g. 400 in FIGS. 3 and 8) comprising at least two well processing stations such as drilling stations, wherein the well processing stations are capable of operating independently of each other. In some embodiments, the well processing stations are each capable of constructing a well simultaneously. When operational, the distance between the two well processing stations may be fixed. Each of the at least two well processing stations may comprise their own mud supply, well control system, and mud return systems.

(97) A shared second position for a number of conductors (or a zone or area around it; see e.g. FIGS. 6a and 6b) may be used—e.g. after one or more wells have been completed at the second position—to complete one or more additional wells, e.g. those additional wells will have first positions of the upper ends located overlapping fully or partly with the second position(s) in question or a zone or area around the shared second position(s). In this way, the wellhead platform may support a higher number of conductors and wells.

(98) When moving upper parts of conductors as disclosed, it should preferably be ensured that no well collisions or even near-collisions occur at/near the surface and/or near the seabed well template (and in-between).

(99) The spacing between conductors at the seabed well template will have an influence on the risk of well collision and a certain minimum conductor to conductor distance (at the well template) is preferred. In some embodiments (assuming grid or array arrangement or similar), the spacing between conductors in a first direction is about 1.1 to about 1.4 meters and about 1.8 to about 2.0 meters in a second direction (perpendicular to the first direction). In some embodiments, the spacing in a first direction is about 1.3 and about 1.9 in a second direction (perpendicular to the first direction).

(100) According to one aspect, the upper parts of the conductors are moved in a certain way in response to what certain predetermined criteria specify. The criteria may involve how the conductors (and e.g. their production trees, etc.) are arranged including their individual location and spacing at the wellhead platform (which depends on an actual design) and how the conductors are arranged at the seabed level. Often there will be a difference between the layout of the conductors at the wellhead deck level and at the seabed level.

(101) In some embodiments, the conductors are moved, in response to what the certain predetermined criteria specify, either a) within a first area near or at the configurable support structure (e.g. at or near, e.g. below, wellhead deck level) wherein an extent of the first area is larger than an extent of a second area, the second area surrounding the relevant conductors at seabed, or b) within a first area near or at the configurable support structure (e.g. at or near, e.g. below, wellhead deck level) wherein an extent of the first area is smaller than an extent of a second area, the second area surrounding the relevant conductors at seabed.

(102) The first possibility a) gives sort of a ‘flower bouquet’ area encompassing the conductors from the seabed to the wellhead deck while the second possibility b) gives sort of a ‘birdcage’ area encompassing the conductors from the seabed to the wellhead deck.

(103) Rigid guidance is preferred at seabed or close to seabed. One or more conductor guides, e.g. as shown in FIGS. 11a, 11 b, 12a, 12b, 13a-13c, 14, and 16, secured to the main structure of the wellhead platform will enable this (see e.g. FIG. 21), especially if the conductors are driven or installed after main structure installation.

(104) In some embodiments, the configurable support structure 200 may provide a number of third compensation positions e.g. as shown in FIGS. 9, 10, and 17-18.

(105) Note that the shown position of the second position(s) of the upper end(s) is shown somewhat idealized in FIG. 2 (and FIGS. 4a-4m, 10, 17 and 18). Due to tolerances the one or more shared second positions may have a position within the working center zone 250 (see e.g. also 250 in FIGS. 5, 6a-6b, 7 and 24).

(106) FIG. 3 schematically illustrates a perspective view of an exemplary embodiment of an offshore wellhead platform and an offshore well processing system.

(107) Shown is a wellhead platform 100 comprising a configurable support structure 200 such as the ones shown and explained in connection with FIGS. 1 and 2 and throughout the present description. The wellhead platform 100 may e.g. also comprise a wellhead deck and cellar deck 101 or similar, in this example comprising or at least partly coinciding with the configurable support structure 200.

(108) Shown are also a number of conductors 210 as described earlier after well completion where a production tree 420 or the like is located on a wellhead of the well.

(109) Further shown is an offshore well processing system 400 comprising at least one (here as an example two, but it could be more than two) well processing station 410 such as a drilling station. In case of multiple well processing stations or multiple drilling stations 410, they may be similar or alternatively be different.

(110) The offshore well processing system 400 will typically comprise a drill floor defining a well processing center also referred to as a well center. When performing one or more well processing tasks, the well center will be located above the upper end of a second position and a riser or the like 430 will extend from the well processing station(s) or drilling stations 410 to the well at a second position being worked upon on the wellhead platform 100.

(111) At least one suitable mechanism is provided on the offshore wellhead platform 100 and/or on the offshore well processing system 400 for moving the upper end of a conductor 210 between a first position and a second position as already explained.

(112) In embodiments comprising two (or more) well processing stations or drilling stations 410, the well processing stations or drilling stations 410 may work fully independently or alternatively also be able to cooperate at least for some functions.

(113) In some embodiments, the offshore well processing system 400 comprises at least 2 well processing stations or drilling station 410, wherein the well processing stations or drilling stations 410 are capable of operating independently of each other but where e.g. one may assist the other. When operational, the distance between the two well processing stations or drilling stations 410 may be fixed. In further particular embodiments, each of the at least two well processing stations or drilling stations 410 comprises its own fluid system and well control system.

(114) FIGS. 4a-4m schematically illustrate a number of different exemplary configurations of first and second positions in a plane or at deck.

(115) Shown in FIG. 4a-4m are exemplary embodiments of a configurable support structure 200 (only the relevant horizontal section is shown) or part thereof, such as the ones shown and explained in connection with FIGS. 1-3 and throughout the present description, comprising a number of first and second positions 150, 160 according to a given layout, arrangement, etc.

(116) Shown in FIG. 4a is an arrangement corresponding except as otherwise noted to the embodiment of FIG. 2 that comprises one centrally located shared second position 160 with a number, here ten, first positions 150 being located around the central shared second position 160 in a substantially circular pattern. In the particular shown embodiment, a center-to-center distance from the shared second position 160 to each of the first positions 150 in the plane shown is substantially equal, although it does not need to be (see e.g. FIG. 4i).

(117) This particular arrangement provides increased flexibility as it may support a greater number of conductors (and thereby wells) than e.g. the arrangement shown in FIG. 2 due to a greater number of first positions 150.

(118) In some embodiments, the first positions 150 (e.g. of a cluster; see below) may be arranged differently, e.g. in an oval pattern as shown in FIG. 4j, in lines as shown in FIGS. 4k-4m, or in any other suitable pattern for a given design and/or need.

(119) In some embodiments, the conductors may e.g. be arranged in one or more clusters, e.g. as shown in connection with FIGS. 4d-4m, where a cluster of conductors e.g. may be associated with at least one shared second position of the upper ends.

(120) In some embodiments, the arrangement of first and second positions 150, 160 may e.g. comprise two (or more) shared second positions 160, e.g. as shown in FIGS. 4d-4h and 4j-4m.

(121) Shown in FIG. 4b is an arrangement corresponding to the embodiment of FIG. 4a with the exception that it comprises eight first positions 150 instead of ten.

(122) This particular arrangement also provides increased flexibility as it may support a greater number of conductors than e.g. the arrangement shown in FIG. 2 due to a greater number of first positions 150.

(123) Shown in FIG. 4c is an arrangement corresponding to the embodiment of FIG. 4a with the exception that it comprises twelve first positions 150 instead of ten.

(124) In this way, increased flexibility is provided as explained.

(125) Shown in FIG. 4d is an arrangement corresponding to the embodiment of FIG. 2 but where the first and second positions 150, 160 of the upper ends of the conductors in the cluster generally are arranged or organized in two clusters 600 where each cluster 600 is represented schematically by a dashed circle.

(126) In this particular embodiment, each of the two clusters 600 comprises an arrangement corresponding to the arrangement of FIG. 2, i.e. each cluster 600 comprises one centrally located shared second position 160 of the cluster with six first positions 150 being located around the central shared second position 160 (of the particular cluster) in a substantially circular pattern.

(127) In this arrangement, each of two well processing stations or drilling stations (not shown; see e.g. 410 in FIGS. 3 and 8) may perform well processing tasks via a conductor located at the shared second position 160. In this particular and corresponding embodiments, one second position 160 of a cluster 600 may be associated with a particular well processing station.

(128) This enables parallel, overlapping, and/or concurrent processing of two wells or conductors at a time further increasing efficiency and/or flexibility in relation to well operations.

(129) In some embodiments, one or more clusters 600 may each have two (or more) shared second positions 160, e.g. as shown in FIG. 4j.

(130) In some other embodiments, the first and second positions 150, 160 of the upper ends of the conductors in the cluster may be arranged in more than two clusters 600, each cluster 600 having at least one second position, e.g. as shown in FIGS. 4k and 4l with three clusters 600, in FIGS. 4e and 4g with four clusters 600, in FIGS. 4h and 4m with six clusters 600, etc.

(131) In some embodiments, two (or more) clusters 600 may be connected in such a way that at least one conductor (and thereby well) may be moved between a number of clusters 600. Examples of such embodiments are shown in FIGS. 4k-4m but such connected clusters could equally be for other arrangements e.g. connecting the two clusters in FIG. 4d, connecting two or more of the four clusters of FIG. 4e, and so on.

(132) It is to be understood that in other embodiments, a cluster 600 could be arranged differently e.g. as shown in FIGS. 4a-4c and 4i-4m and variations falling within the scope of the appended claims.

(133) It is also to be understood that for embodiments comprising a plurality of clusters 600, the relative arrangement of first and second positions of the upper ends 150, 160 does not need to be the same for each cluster 600, e.g. the number of and/or the layout of the first and/or second positions 150, 160 may be different.

(134) Shown in FIG. 4e is an arrangement corresponding to the embodiment shown and described in connection with FIG. 4d but where the arrangement comprises four clusters 600 instead of two. The applicable variations mentioned in connection with FIG. 4d and elsewhere are equally applicable for the embodiments of FIG. 4e.

(135) This further increases efficiency and/or flexibility e.g. by enabling parallel, overlapping, and/or concurrent processing of several wells or conductors at a time (e.g. still two at a time but possibly more). Additionally, an increased number of wells to be supported are provided.

(136) Shown in FIG. 4f is an arrangement corresponding to the embodiment shown and described in connection with FIG. 4d but where each cluster 600 comprises an arrangement according to FIG. 4c instead of FIG. 2.

(137) Shown in FIG. 4g is an arrangement corresponding to the embodiment shown and described in connection with FIG. 4e but where each cluster 600 comprises an arrangement according to FIG. 4a instead of FIG. 2.

(138) Shown in FIG. 4h is an arrangement corresponding to the embodiment shown and described in connection with FIG. 4d or 4e but where the arrangement comprises six clusters 600 instead of two or four.

(139) Shown in FIG. 4i is an arrangement corresponding except as otherwise noted to the embodiment of FIG. 4a that comprises one centrally located shared second position 160 with a number, here twelve, first positions 150 being located around the central shared second position 160. A difference to the embodiment of FIG. 4a—apart from comprising a different number of first positions—is that the center-to-center distances from the second position 160 to each of the first positions 150 in the plane are not the same.

(140) Rather, one part of the first positions 160 have a same distance to the central second position 160 while the remaining part of the first positions 160 have a another (but still same for that part) distance to the second position 160 where the first positions 160 are arranged so that the distance is alternating (i.e. a first position has a distance to the second position that is different from the distance of its immediate neighbors) giving of a ‘star-like’ arrangement.

(141) This provides a more compact arrangement for a given number of first positions 160.

(142) In some embodiments, the level of the conductors (and thereby the production trees eventually installed at the top of the conductors) will vary or alternate e.g. between two different levels. This provides more room for maneuvering the conductors between the first and second positions in the compact arrangement.

(143) Shown in FIG. 4j is an arrangement corresponding except as otherwise noted to the embodiment of FIG. 2 that provides a number, here two, of centrally located shared second positions 160 and a number, here eighteen, first positions 150 being located around both central shared second positions 160 in a substantially oval pattern.

(144) In the particular shown embodiment, a center-to-center distance from a (closest) second position of the upper end 160 to a first position of the upper end 150 is not the same for all first positions, even though some of the first positions have a substantially equal distance to the (closest) shared second position.

(145) This arrangement, and corresponding ones, provides flexibility in that a conductor at any first position may be brought to one of the second positions. Furthermore, a relative compact arrangement is also provided.

(146) Shown in FIG. 4k is an arrangement somewhat different from the earlier ones. The first and second positions still correspond to the first and second positions explained elsewhere. This particular arrangement provides a number, here three, clusters 600 where each cluster 600 provides a centrally located shared second position 160 of the upper ends of the conductors in the cluster and a number, here four, of first positions 160 arranged at a (side-)‘line’ on opposing sides of the central shared second position 160 so that a conductor from a first position at one end or side-line can be moved to a first position at the other end or side-line by moving past the shared second position.

(147) Furthermore, the three clusters 600 in this arrangement is connected—specifically by a line comprising the three shared second positions—so that a conductor may be moved from a first position in any cluster to a first position in all the other clusters.

(148) This and corresponding arrangements facilitate sort of a ‘factory line’ or serial well processing procedure. As an example, well processing equipment may be aligned with the shared second positions, e.g. one well processing equipment at each second position, and be rigged to carry out different well processing task and in particular different well processing sub-tasks where one sub-task should be carried out after another, i.e. there is a progression of sub-tasks.

(149) According to the shown and corresponding arrangements, a conductor at a first position near the upper shared second position may be moved to the ‘upper’ shared second position where a first (one or more) task and/or sub-task is carried after. After this, the conductor may be moved to the ‘middle’ shared second position where different one or more tasks and/or sub-tasks is/are carried out and so on until another one or more last tasks and/or sub-tasks has/have been carried out at the ‘lower’ or final shared second position where the conductor then may be moved to a first position e.g. for well-intervention, or production, etc. Such an arranged may increase efficiency in relation to well processing of a number of wells.

(150) It is to be understood that an arrangement corresponding to the one in FIG. 4k may provide another number of shared second positions and/or first positions and the specific arrangement could also be varied according to a given need, e.g. as shown In FIGS. 4l and 4m. The number of first positions on a side could e.g. be smaller or larger. The number of first and/or shared second positions does not need to be the same for each group. Furthermore, the number of first positions at one side of a cluster does not need to be the same as the number of first positions at the other side of the cluster. Additional and applicable variations as explained elsewhere are also possible.

(151) Shown in FIG. 4l is an arrangement corresponding except as otherwise noted to the embodiment of FIG. 4k with a difference that each cluster 600 only comprises one first position on each side of the shared second position instead of two as in FIG. 4k.

(152) Shown in FIG. 4m is an arrangement corresponding more or less and except as otherwise noted to the embodiments of FIGS. 4k and 4l. The shown arrangement provides a number, here six, clusters 600, comprising a second and four first position, where each cluster 600 corresponds to a cluster of FIG. 4k.

(153) The clusters 600 are arranged like two arrangements of FIG. 4k side by side. This could e.g. be referred to as two line arrangements where line refers to a line of shared second positions. In addition, the clusters 600 also share first positions 150 with one neighboring cluster 600. In the shown example, first positions 150 are shared with the neighboring cluster 600 on the other line arrangement. So not only may a conductor be moved from shared second position to shared second position (in a given line arrangement) but it may also be moved to another/the other line arrangement.

(154) This increases flexibility in relation to well operations possibilities.

(155) FIG. 5 schematically illustrates at least a part of a configurable support structure together with an appropriate working center zone.

(156) Shown is at least a part of a configurable support structure 200 providing a number of first positions 150 and a number of shared second positions 160 where the structure corresponds to configurable support structures as described elsewhere. This particular exemplary configurable support structure 200 comprises two shared second positions 160 and eight first positions arranged in a given arrangement.

(157) One or more of the first positions comprises a conductor 210 comprising at least one conduit 215, e.g. a 20″ conduit, and having a clearance gap 225 between the outer part of the conductor 210 and the conduit 215.

(158) Indicated is a working center zone 250 projected or superimposed on to the plane shown, e.g. projected or superimposed on a wellhead deck of the offshore wellhead platform. The offset zone 230 is to be positioned under the well processing station(s) of an offshore well processing system (see e.g. 410 and 400 in FIGS. 3 and 8). The working center zone 250 comprises an offset zone 230 or the like to accommodate for tolerances when positioning the offshore well processing system to perform one or more well processing tasks on the wells of the configurable support structure 200. In some embodiments, the working center zone 250 further comprises an additional zone 235 to safely accommodate effects of weather on equipment during performing well processing tasks.

(159) In some embodiments, the working center zone 250 (and in particular the offset zone) will have a generally elongated shape (that does not need to be square; it could e.g. be oval or other). This is advantageous for offshore well processing systems having its well processing station(s) located on a cantilever system or the like.

(160) Larger tolerance, and thereby size of the working center zone 250, is generally advantageous in the transverse direction (left/right in FIG. 5) of the primary movement direction of the cantilever system and less in the primary movement direction (up/down in FIG. 5).

(161) The working center zone 250 should be designed to not be too large, as this will take up valuable working space on the wellhead platform.

(162) In some embodiments, the working center zone 250 has dimensions selected from about 0.25×0.25 meters to about 10×25 meters. In some embodiments, the working center zone 250 has dimensions being about 5×15 meters. In some embodiments, the working center zone 250 has dimensions being about 3×10 meters. In some embodiments, the working center zone 250 has dimensions being about 2×7.5 meters. In some embodiments, the working center zone 250 has dimensions being about 1.5×5 meters. In some embodiments, the working center zone 250 has dimensions being about 1.3×4 meters.

(163) FIGS. 6a and 6b schematically illustrate at least a part of a configurable support structure before and after conductors have been installed at first positions located in a working center zone.

(164) Shown in FIG. 6a is at least a part of a configurable support structure 200 providing a number of, here as an example one, shared second positions 160 and a number of, here as an example nine, first positions 150. Further illustrated is a working center zone 250, a transit zone 275, and a number of conductors 210.

(165) The transit zone 275 is a zone defining the space needed for moving an upper part of the conductors 210 between relevant first and second position(s) 150, 160. According to one convention, the transit zone 275 will not comprise the (regular) first positions 150 (except for the additional wells completed subsequently according to some embodiments—as explained below) in the working center zone 250. It should be noted that physically, the configurable support structure 200 will generally comprise an opening (at least) being of about the size of the transit zone 275 and the (regular) first positions 150, e.g. including further space if preferred. According to this convention, the transit zone 275 may be seen as an upper physical opening of the configurable support structure 200 minus the space needed for the (regular) first positions.

(166) As can be seen, wells have been completed at the top-most and bottom-most lines as indicated by conductors 210 comprising a valve assembly or production tree e.g. also referred to as Christmas tree, x-mas tree, etc. being mounted on the wellhead.

(167) In FIG. 6a, wells at first positions 150 in the working center zone 250 have not been completed while wells at one or more (in the FIG. 6a it is all) of the regular first positions—outside the working center zone 250—have been completed.

(168) FIG. 6b corresponds to FIG. 6a with the exception that here the wells in the first positions 150 (then e.g. denoted additional first positions) in the working center zone 250 have now been completed.

(169) This illustrates that after wells have been completed outside the working center zone 250 (i.e. the ‘regular’ first positions), the area of the working center zone 250 itself may be used to prepare an additional number of wells after the other ‘regular’ wells have been prepared since this space is no longer required for bringing the conductors of the ‘regular’ first positions 150 to the shared second position 160 (at least not for well construction). In this way, even the area of the working center zone 250 becomes productive after being used for the wells of the ‘regular’ first positions.

(170) The double arrows illustrate the movement of the upper ends (not necessarily the actual path) of conductors between first and second positions 150, 160 as explained already.

(171) FIG. 7 schematically illustrates at least a part of a configurable support structure with a working center position at two different positions.

(172) Shown is at least a part of a configurable support structure 200 providing a number, here as an example two, shared second positions 160 and a number, here as an example twenty, first positions 150 each eventually comprising a conductor 210. Further illustrated is a working center zone 250 and a transit zone 275.

(173) During exemplary operation, the working center zone 250 is first at a lower position with the lower shared second position 160 where ten (or less) wells may be completed at the bottom ten first positions 150. After the bottom ten or less wells have been completed, the working center zone 250 is moved (e.g. by moving a cantilever system and the well center as explained elsewhere) from the indicated position to the upper shared second position 160 where the upper ten (or fewer) wells then may be completed. This process could in principle be continued.

(174) The transit zone 275 is generally not moved.

(175) The double arrows illustrate the movement of the upper ends or the upper parts shown in the plane (not necessarily the actual path) of conductors between first and second positions 150, 160 as explained already.

(176) As noted above FIG. 3 illustrates a front view of an exemplary embodiment of an offshore wellhead platform and an offshore well processing system.

(177) Shown is a wellhead platform 100 comprising a configurable support structure 200 such as the ones shown and explained in connection with FIGS. 1 and 2 and throughout the present description. The wellhead platform 100 may e.g. comprise a wellhead deck, cellar deck 101 or similar The well processing system 400, here as an example in the form of a jack-up drilling unit comprising at least one (such as two, three or more) well processing station 410 such as at least one drilling station. In some embodiments, the offshore well processing system 400 comprises at least two well processing stations or drilling stations 410.

(178) Further shown is a main structure 510 for supporting an upper deck structure of the wellhead platform 100.

(179) Shown are a number of conductors 210 as described earlier after well completion where a production tree 420 or the like is located on a wellhead of the well.

(180) The offshore well processing system 400 will typically comprise a drill floor defining a well center through which one or more well processing tasks may be performed. When performing one or more well processing tasks, the well center will be located above the shared second position(s) and a riser or the like 430 will extend from the well processing station 410 to the well at a shared second position being worked upon on the wellhead platform 100.

(181) The drill floor and well center may be positioned on a cantilever system 405 that can be extended horizontally outwards relative to the hull of the offshore well processing system 400, thus allowing the well center to be positioned outside the periphery of the unit as defined by the hull of the unit.

(182) The main structure 510 of the wellhead platform may also comprise a seabed well template comprising a number of conductor guides 501 e.g. as shown in FIGS. 11a and 11b and/or a number of double-conductor guides 505 e.g. as shown in FIG. 22.

(183) In some embodiments, the main structure 510 and/or the wellhead platform 100 may e.g. support and/or guide conductors as described in connection with FIG. 21.

(184) At least one suitable mechanism is provided on the offshore wellhead platform 100 and/or on the offshore well processing system 400 for moving an upper part of a conductor 210 between a first position and a second position as already explained.

(185) FIG. 8a schematically illustrates a front view of an offshore wellhead platform and an offshore well processing system, such as those of FIG. 3, but shows only conductors, deck, and some of the configurable support structure.

(186) Shown is a wellhead platform 100 comprising a configurable support structure 200. The wellhead platform 100 comprises a wellhead deck 101 that also constitutes the cellar deck, a x-mas tree access deck 102 and a main deck or weather deck 103. The cellar deck comprises two large openings 101a/b, which are part of the configurable support structure and allow movement of the upper part of the conductors 210. Corresponding openings 102a/b are also provided in the x-mas tree access deck 102. Further openings 103a/b are provided in the main deck. The opening 101a allows the conductors 210a′ and 210a″ to move their upper parts into alignment with work center position of the wellhead platform indicated by the dashed line 417a. Similarly, the opening 101b allows the conductors 210b′ and 210b″ to move their upper parts into alignment with work center position of the wellhead platform indicated by the dashed line 417b. Accordingly, the conductors 210a′ and 210a″ are arranged in one cluster and conductors 210b′ and 210b″ are arranged in a second cluster with the shared second positions of the upper ends aligned respectively with the working center 417a and 417b.

(187) The wells of the conductors 210a″/b″ have been completed, X-mas trees 420a/b and wellheads 415a/b have been installed and that have been placed in their respective first positions. The conductors 210a″/b″ are shown as straight in the first positions but a as discussed the conductors may be straight in other positions of the upper end e.g. in a position between the first and second positions. The conductors 210a′ and 210b′ are placed in their respective second positions and connected to the well processing system 400 (in the form of a jack-up drilling unit (partially shown)) via a high-pressure riser 430. Shown is a cross section of a single cantilever 405 of the drilling unit with two drilling stations (only the drill floor and below is indicated) with diverter systems 419a/b located underneath the drill floor 501a/b and drill pipe 502a/b entering the upper end of the diverter through indicating the well centers of the drilling stations. The well centers are aligned with working centers 417a/b of the two clusters defined by the openings 101a/b. An exemplary top view of the layout of the configurable support structure the deck 101 is provided along the dashed line 507 in the insert. Here the conductors are seen as open circles.

(188) An optional mezzanine wellhead access deck 503 is provided comprising openings for allowing the movement of the conductors partially installed with deck inserts, e.g. gratings, (indicated by the dotted lines around the deck section) for allowing a safe work platform. Such deck inserts may be installed in any of the openings of the other decks e.g. to provide work platforms.

(189) Horizontal frames 504/505 for providing support elements and transferring any loads to the wellhead platform are further provided at lower levels above and below water, respectively. The conductor 210a′ and 210b′ are shown schematically as bend in a straight line from seabed 120 to upper end. However, generally the conductor may bend in other shapes and the support elements may be movable or fixed and above water 504 and below water 505. The support elements at lower levels may be arranged so that in the second position they are not aligned with the working center position 417 as illustrated for 505. The frame 506 provides fixed support elements for the conductors.

(190) As discussed through the description, the configurable support structure typically comprises support elements (not shown) at least for engaging with the conductors 210 at least in the first position but preferably moving with the conductor as it is moved between the first and second positions. Here such support elements are placed in or at the cellar deck 101 and in the guide frames 504 and 505.

(191) FIG. 8b shows and embodiment to similar to that of FIG. 8a and schematically illustrates a front view of an offshore wellhead platform and an offshore well processing system. In this case the mezzanine wellhead access deck 503 is replaced by a full deck 508 now acting as a wellhead deck and preferably comprising support elements (not shown) such as guides to support the conductors at least in the first position but preferably as movable support elements that can support the conductors in their first and second positions. The cellar deck 101 is now separate from the wellhead deck 508.

(192) For FIGS. 8a and 8b, all movement mechanisms (not shown) may be located on the cellar and/or the wellhead deck 508 and/or the horizontal frame 504. The 505 may also be used but it is most likely preferable to keep the movement mechanism in the dry zone.

(193) Generally, and in particular for movable support elements it may be preferably to provide them with position sensors and/or load sensors—particularly if they are hard to access such as under water.

(194) FIG. 9 schematically illustrates side force compensation according to one aspect of the present invention.

(195) Illustrated is a configurable support structure 200 (only the relevant horizontal section is shown) providing a number (here six as an example) of first positions 150 and a number (here one as an example) of second positions 160 shared by the respective upper parts of the conductors. The first positions 150 are here located substantially equidistantly around a central second position 160.

(196) An upper part of a conductor 210 has been moved from a first position (shown as the leftmost one in the Figure, i.e. the non-filled circle) to the central second position 160.

(197) When the upper part of the conductor 210 is moved from its (current) first position to the second position 160 by at least one suitable conductor moving mechanism, the conductor moving mechanism will generally apply a force on the conductor in the direction of movement as indicated by the arrow denoted F_i (in the shown example going from left to right) and labelled 301. The conductor will in turn generate a force acting on the main structure of the wellhead platform in the opposite direction than the direction of movement as explained further below.

(198) The suitable conductor moving mechanism may e.g. be any mechanism capable of moving (the upper part) of a conductor 210 e.g. by pulling, pushing, etc. e.g. such as mechanical or hydraulic push or pull, a rack and pinion drive, winch-wire, or any other suitable mechanisms for retaining, moving, shifting, etc. Examples of a suitable mechanism or system are e.g. given in FIGS. 17, 18, and 24 (see 550).

(199) The force 301 will generally cause at least some bending stress in the conductor 210 and also generally cause stress on the main structure of the wellhead platform (not shown; see e.g. 510 in FIG. 3) via various support elements (such as supports, guides, securing elements, etc.) connecting the conductor 210 and the main structure of the wellhead platform. Depending on specific circumstances, stress may also be applied to a seabed well template through which the conductors run into the seabed. The force 301 may also be present from maintaining the upper part of the conductor 210 in the second position 160 (given the conductors minimum stress state is different from the second position 160).

(200) According to one aspect, the stress to the main structure of the wellhead platform is relieved or alleviated at least to some extent by applying a counter force (from one or more sources) to one or more other conductors in one or more predetermined directions so that the applied counter force will negate or reduce the force 301 at least to an extent, and preferably below a predetermined minimum force tolerance level.

(201) This will reduce the amount of stress that the main structure of the wellhead platform would otherwise be subjected to due to movement of a conductor as described.

(202) As one example, two counter forces denoted F_i+1 and F_i−1 and labelled 302 are shown in FIG. 9.

(203) In some embodiments, at least one support element is adapted to apply the one or more counter forces 302 that will reduce the impact of the movement force 301 on the main structure of the wellhead platform. In some embodiments, the at least one support element is the same mechanism that is used to move the upper part of the conductor 210 to the second position 160.

(204) In some embodiments (with at least one central second position 160), the one or more predetermined directions of the counter forces 302 are directed away from the central second position 160 e.g. as shown.

(205) In some embodiments, the counter forces 302 are applied to the two immediately neighboring or adjacent conductors (as signified by the notation i−1 and i+1).

(206) The conductor(s) that the counter forces 302 are applied to will also in turn generate a force acting on the main structure of the wellhead platform in the opposite direction than the direction of movement of that or those conductors.

(207) The counter forces 302 may e.g. be applied to other conductors instead or in addition. They may e.g. also be applied to only a single conductor (but then less optimally) or more than two conductors, e.g. four (preferably for embodiments with more than six first positions), etc.

(208) The applied counter forces 302 may be selected, and preferably are, so that the sum of resulting forces acting on the conductors (the ones being moved) is substantially close to zero, or at least below a certain sufficient minimum level. I.e. the sum of (the vectors of) the force 301 and the counter forces 302 should be about close to zero or be less than the predetermined minimum force tolerance level.

(209) The counter forces 302 should be applied when the upper part of the conductor 210 is moved to (and e.g. maintained in) the second position 160.

(210) The conductors that counter forces 302 is applied to would need room for movement. This may e.g. be provided as shown in FIG. 10.

(211) The aspect of applying counter forces as described above may be used regardless of a location of a natural minimum stress situation of the conductors 210.

(212) Furthermore, the aspect of applying counter forces is not dependent on the specific layout of the conductors 210. It may even be used for conductors arranged in a grid or other patterns. When a conductor is moved in one certain direction, one or more conductors located beyond the starting point opposite the certain direction may contribute to reducing the force 301 at least to an extent, and preferably below a predetermined minimum force tolerance level.

(213) FIG. 10 schematically illustrates one exemplary embodiment of a configurable support structure facilitating side force compensation e.g. as illustrated in FIG. 9.

(214) Shown is at least part of a configurable support structure 200 corresponding to the one shown in FIG. 2 (and variations thereof) except as noted in the following.

(215) The shown configurable support structure 200 (and corresponding embodiments) further provides a number of third compensation positions 165 for the conductors 210. In the shown example, the configurable support structure 200 comprises a single third compensation position 165 for each first position 150, even though it may be different, e.g. a third compensation position 165 for only one or some of the first positions 150.

(216) The third compensation positions 165 are located more distantly from a central second position 160 than the first positions and the configurable support structure 200 further allows movement of an upper part of a conductor 210 between its first position 150 and its third compensation position 165.

(217) In this way, it is possible to relieve or alleviate stress on the main structure of the wellhead platform—e.g. as shown and described in connection with FIG. 9—by moving the upper part of at least one, preferably an even plurality, of other conductor(s) 210 to its or their third compensation position(s) 165 when an upper part of a conductor 210 is moved to its second position 160 as represented by the three large arrows in the figure.

(218) It should be noted, that movement of an upper part of a conductor directly from a second position to a third compensation position is not excluded and may depend on actual design of the configurable support structure 200.

(219) In some embodiments, the upper part of conductor(s) being moved to its or their third compensation position(s) 165 are an upper part of conductors (210) being, e.g. most closely neighboring or adjacent conductors to the conductor having its upper part moved from its first position 150 to a second position 160.

(220) It should be noted, that well processing tasks, such as drilling, completion, etc., may e.g. also be carried out through a conductor 210 when it is located at a third compensation position 165.

(221) FIGS. 11a and 11b schematically illustrate side and top (or bottom) views of an exemplary conductor guide according to one aspect of the present invention.

(222) Shown in FIG. 11a is a side view and a top (or bottom) view of one support element in the form of a conductor guide 501 for being secured to a main structure of the wellhead platform where the conductor guide 501 is—in this and corresponding embodiments—substantially cylindrical and comprises a central through-going cavity 502 adapted to receive a part of a conductor 210. The conductor 210 is shown in a vertical position. The size of the cavity should allow for some space between a received conductor 210 and an inner wall of the conductor guide 501. This space will allow for some movement of a received conductor 210 due to movement of its upper part.

(223) In some embodiments, and as shown, the conductor guide 501 is generally elongated and comprises two opposing ends 503 where each end 503 comprises a funnel shape with the funnel expanding outwards from a center/central point of the conductor guide 501.

(224) Shown in FIG. 11b is a side view and a top view of the same conductor guide 501 as shown in FIG. 11a but where it is shown as being secured to a securing part or element (such as a support beam or other) of the main structure 510 of the wellhead structure to support a conductor 210. Furthermore, the conductor 210 is shown in a moved position as will generally happen when the upper part of the conductor is moved between a first and second (or third) position as described elsewhere.

(225) As can be seen the funnel shape at both ends 503 of the conductor guide 501 readily accommodate the movement of the conductor even if the conductor guide 501 would be placed at lower levels underwater closer to the seabed than the offshore wellhead platform.

(226) This particular conductor guide 501 and corresponding embodiments thereof are a so-called passive guide, which is advantageous to use sub-sea, as it is simpler and generally would require less or no maintenance. Such conductor guides 501 may e.g. be installed (sub-sea) for as much as up to about 20 years or even longer.

(227) Such a conductor guide 501 may also assist in securing and/or guiding a conductor during installation when the conductor is being secured into the seabed.

(228) As mentioned, such a conductor guide 501 may also allow a tilt movement to some degree thereby accommodating a (tilting) movement of the conductor 210 when its upper part is moved.

(229) In some embodiments, the conductor guide 501 is also lockable. Preferably only in the horizontal plane and not in the vertical plan as this would transfer forces (like the weight of the well, etc.) to the main structure 510 of the wellhead platform.

(230) FIGS. 12a and 12b schematically illustrate a number of conductor guides, such as the ones shown in FIGS. 11a and 11b, and a number of restriction elements according to some embodiments.

(231) Shown in FIG. 12a is a top (or bottom) view of two conductor guides 501 e.g. corresponding to the one shown in FIGS. 11a and 11b. Alternatively, the conductor guide 501 may be of another type. The conductor guides 501 are each connected to a securing part or element (such as a support beam or other) 510 of the main structure of the wellhead platform by a restriction element 520 that restricts movement of a conductor guide 501 to be possible only along one direction, i.e. with one degree of freedom, but back and forth. In some embodiments, the restriction element 520 is a (passive) telescopic element, like shown in the figure. Alternatively, the restriction element 520 is or comprises a resilient element or other.

(232) A restriction element 520 is secured to the main structure 510 of the wellhead platform at an appropriate angle ‘a’ that defines the possible movement direction (back and forth). The angle may be the same or different for various restriction elements 520.

(233) In this way, controlled movement of a conductor 210 along a particular direction is facilitated while generally supporting the conductor 210 (while still allowing it to move), which increases the structural stability when moving conductors between various positions.

(234) The particular direction as allowed by the restriction element 520 (both the shown one and variations thereof as well as restriction elements and variations thereof as shown in other Figures, e.g. FIGS. 13a-13c and 14) will generally be between first and second (and/or third) positions.

(235) It is noted, that the travel length of conductors 210 and conductor guides 501 at different levels (water depths) will generally not need to be the same. The movement distance is largest at or near the configurable support structure/upper part of the wellhead platform, and smallest at or near the seabed well template.

(236) Shown in FIG. 12b is a top view of the same conductor guides 501 as shown in FIG. 12a but where the conductors 210 now have been moved.

(237) FIGS. 13a-13c schematically illustrates a conductor guide, such as the ones shown in FIGS. 11a and 11b, and a restriction element according to some alternative embodiments.

(238) Shown in FIG. 13a is a top view of a restriction element 520 secured to a securing part or element (such as a support beam or other) of the main structure 510 of a wellhead platform in order to support a conductor 210.

(239) This and similar embodiments of a restriction element 520 also only provide one degree of freedom for moving a contained conductor 210. More specifically, the restriction element 520 comprises a through-going slot, slit, or the like 521 into which a conductor guide 501 is located as shown in FIGS. 13b and 13c.

(240) In this way, controlled movement of a conductor 210 along a particular direction (in both directions as indicated by the double arrows) is facilitated while generally supporting the conductor 210 (while still allowing it to move). This increases the structural stability when moving conductors between various positions.

(241) The restriction element 520 function particularly well with a conductor guide 501 as shown e.g. in FIGS. 11a and 11 b.

(242) Shown in FIG. 13b is a top view of the restriction element 520 but now including a conductor guide 501 as shown e.g. in FIGS. 11a and 11b. One conductor guide 501 comprising a part of a conductor 210 is shown in two positions while a double arrow indicates possible movement. Shown in FIG. 13c is a side view of the restriction element 520 including the conductor guide 501.

(243) As can be seen, the restriction element 520 is in this and corresponding embodiments adapted to engage a contained conductor guide 501 at a middle or central part between its two funnel shaped ends. The through-going slot, slit, or the like 521 will together with the funnel shapes effectively prevent (too much) upwards or downwards movement of the conductor guide 501 while still allowing it to slide or move in both directions along the through-going slot, slit, etc. This increases the structural stability when moving conductors between positions.

(244) FIG. 14 schematically illustrates a conductor guide, such as the ones shown in FIGS. 11a and 11b, and a restriction element according to yet other alternative embodiments.

(245) Shown in FIG. 14 is a side cross-sectional view and end or side view along a possible movement direction of another type of restriction element 520 also only providing one degree of freedom for moving a contained conductor guide 501 comprising a conductor 210.

(246) The restriction element 520 according to these embodiments also comprises a through-going slot, slit, or the like for receiving the conductor guide 501. In addition, the restriction element 520 comprises a groove 523 along the direction of possible movement for engaging with a head or other 522 located substantially centrally and on opposite sides of the conductor guide 501. This prevents (too much) upwards and downwards movement of the conductor guide 501 while still allowing it to slide along the slot, slit, etc. Furthermore, the engaging head or other 522 may have a substantially circular outer surface fitting into the groove 523, which will allow the conductor guide 501 to tilt thereby accommodating a (tilting) movement (if any) of the conductor 210 when its upper part is moved.

(247) The shape of the surface of the head or other 522 engaging with the groove 523 may be different than circular. As other examples are e.g. oval, partly oval, as also illustrated in FIG. 14, or other suitable shapes.

(248) In this way, controlled movement of a conductor 210 along a particular direction is facilitated while generally supporting the conductor 210 (while allowing it to move). This increases the structural stability when moving conductors between various positions.

(249) FIG. 15 schematically illustrates a conductor guide, such as the ones shown in FIGS. 11a and 11b, and conductor positioning elements according to some embodiments.

(250) Shown is three states of a conductor guide 501, e.g. like the ones shown in FIGS. 11a and 11b, with the addition that it comprises at least one internal positioning element 530 adapted to actively position or alternatively passively follow a conductor 210 contained within the conductor guide 501. The conductor 210 may be supported at the same time.

(251) In the shown and in corresponding embodiments, the internal positioning element 530 comprises at least three piston elements or similar secured internally to the conductor guide 501 where each piston element further comprises a (partially) rotating (passive) abutment element or the like at the end facing a conductor 210 when received by the first conductor guide 501.

(252) If the at least one internal positioning element 530 is/are passive it will merely follow and/or impose a passively induces force (and support) the conductor 210.

(253) However, if the at least one internal positioning element 530 is/are active it may be possible to control the x-y position (not up/down or z) of the conductor 210 within the conductor guide 501 well.

(254) Shown to the left, is a state where the internal positioning element 530 is not active and does not engage the conductor 210 in the conductor guide 501. Shown in the middle, is a state where the conductor 210 has been centered by controlling the pistons' respective central movement as indicated by the three straight double arrows. Shown to the right, is a state where the conductor 210 has been ‘offset’ to a desired position.

(255) An active internal positioning element 530 allows for ‘fine-tuning’ of the position of a conductor 210 (within the conductor guide 501) with two degrees of freedom.

(256) This may e.g. be beneficial if a well processing station such as a drilling station of a drilling unit (see e.g. 400 and 410 in FIGS. 3 and 8) is not fully or sufficiently aligned with a second position or working zone, if movement of the conductor guide 501 itself is not flexible enough for a particular situation, etc.

(257) Furthermore, centered position (middle state) may e.g. be beneficial for conductors having upper parts at their first or second position. Additionally, the inner diameter of a conductor guide can be adjusted (e.g. increased) for certain situations.

(258) FIG. 16 schematically illustrates a conductor guide, such as the ones shown in FIGS. 11a and 11b, and conductor positioning elements according to some alternatives embodiments. Shown is a restriction element 520 being movably attached to the main structure 510 of a wellhead platform where the restriction element 520 is adapted to allow movement of a secured conductor guide 501 only in a predetermined two-dimensional (x,y) plane.

(259) The restriction element 520 may e.g. be comprised by at least one support element.

(260) More specifically in this and corresponding embodiments, the restriction element 520 comprises two piston elements 526 or the like, each being connected to the main structure 510 of the wellhead platform and the secured conductor guide 501 via rotating connectors 524.

(261) The piston elements 526 may e.g. be telescopic as shown or another element providing movement in both directions along a predetermined direction.

(262) By actively controlling the piston element or the like 526, the position of the conductor guide 501 and thereby a contained conductor 210 may be controlled with precision.

(263) FIG. 17 schematically illustrates a configurable support structure and an arrangement for moving a conductor.

(264) The shown configurable support structure 200 correspond to the one shown in FIG. 8 but could also be configurable support structure in another configuration, e.g. like shown in FIGS. 2 and 5 or otherwise described herein.

(265) Shown is a conductor moving system 550 here in the form of a cable anchoring system or similar for selective movement of (an upper part of) a conductor 210 that may form part of at least one support element.

(266) The cable anchoring system 550 comprises a plurality of anchor points 525 (here sixteen) where an upper part of a conductor 210 (presently in the Figure near or at a central second position 165) is secured to the cable anchoring system 550 by a number of (e.g. tensioned) cables to at least three of the anchor points 525.

(267) Alternatively, the conductor 210 may e.g. be secured to at least five anchor points 525 or any other suitable, e.g. odd, number. Conductors 210 received by the configurable support structure 200 may e.g. comprise one or more lifting eyes or similar secured, e.g. welded, to the conductors 210 for attaching a cable.

(268) The three or more (used/active) anchor points 525 are generally arranged at a first side and at a generally opposing second side.

(269) The cable anchoring system 550 is adapted to selectively move (an upper part of) a received conductor 210 by controllably dragging or pulling one or more cables at the first side and controllably extending one or more cables at the second side thereby providing controlled movement of the conductor 210 in a predetermined movement plane. It is noted, that the sides are generally not static, i.e. they depend on what conductor 210 is to have its upper part moved and what directions/what anchor points are pulling and extending a cable.

(270) In some embodiments (and as shown), the plurality of anchor points 525 is divided into a first group 551 and a second group 552 (the groups are not be confused with the first and second sides above) where the first and the second group 551, 552 is arranged in a first and a second substantially oval or circular ring-like pattern, respectively, where the first pattern has a lesser diameter than the second pattern and is located inside the second pattern. Other patterns may also be used depending on specific design.

(271) In some embodiments, anchor points of a group are used to apply force in the same direction. E.g. the anchor points in the (outer) second group 552 may be used to drag or pull a cable while the anchor points in the (inner) first group 551 may be used to extend a cable.

(272) In some embodiments, the anchor points of one group are shifted or offset in relation to the anchor points of the other group. In this way, anchor points used in one group are less obstructed by anchor points of the other group.

(273) In some embodiments, the anchor points are distributed at different height levels. As an example, the anchor points in the first (inner) group 551 may e.g. be located lower than the anchor points in the second (outer) group 552 or whatever is suitable.

(274) In some embodiments, the cable anchoring system 550 is adapted to move conductors 210 to their respective third compensation position 165, e.g. at the same or overlapping time when an upper part of a conductor is moved to a second position 150, as explained in connection with FIGS. 9 and 10, to compensate for side forces and stress. This may e.g. be done by securing cables between suitable anchor points 525 and the upper parts of the conductors to be moved to third positions 165 where the suitable anchor points are located behind the third positions 165, respectively and simply dragging or pulling the cable so the upper part of the conductor is pulled into the third position 165.

(275) In some embodiments, the anchor points of the second (outer) group 552 is located on a circular (or oval, etc.) beam, rail, guide or the like 535 comprising a number of travelling wenches or other suitable equipment. In this way, the anchor points may be moved more or less freely around the central second position 160 and be brought into a desired position. This may also reduce the number of anchor points needed. Only one (outer) anchor point or pulling point is generally needed or three if two conductors are to be moved to their third compensation positions 165.

(276) The cable anchoring system 550 may be located above—or preferably below—the configurable support structure 200.

(277) FIG. 18 schematically illustrates a configurable support structure, e.g. corresponding to the one shown in FIG. 10, and an alternative arrangement for moving a conductor.

(278) The shown configurable support structure 200 correspond to the one shown in FIG. 10 but could also be configurable support structure in another configuration, e.g. like shown in FIG. 2 or 5 or as otherwise described herein.

(279) Shown is conductor moving system 550 here in the form of a cable anchoring system that corresponds to the embodiments shown and explained in connection with FIG. 17 except as noted in the following.

(280) In this alternative cable anchoring system 550, the anchor points 525 are arranged as a single group in a substantially oval or circular ring-like pattern more or less located at a similar position as the second group 552 of FIG. 17. So all anchor points may be used to pull or release (at different times).

(281) The cable anchoring system 550 of FIG. 18 is simpler to implement than that of FIG. 17.

(282) FIG. 19 schematically illustrates a number of conductor separation elements.

(283) Illustrated to the left are a number of conductors 210 (at respective first positions) at different levels (i, i−1, and i+1) being arranged in a circular configuration as an example. Further shown are three conductor separation elements 600, one at each level. A conductor separation element 600 separates or compartmentalizes a number of conductors 210 from others.

(284) The conductor separation elements 600 are rotated in a horizontal plane in relation to each other, e.g. by about 60°. As can be seen from the top view on the right, this effectively separates the conductors from each other. This avoids or at least reduces the risk of the conductors coming into contact with each other, becoming entangled, etc. when the upper parts of the conductors are moved in a simple way.

(285) It is to be understood that another number (more or fewer) of conductor separation elements 600 than three may be used. Furthermore, more than one conductor may be present in one ‘compartment’.

(286) A conductor separation element 600 may e.g. be beam or sheet secured or welded to the main structure of the wellhead platform.

(287) FIG. 20 schematically illustrates one alternative conductor separation element.

(288) Shown is a conductor separation element 600. This provides a same effect as the separate conductor separation elements of FIG. 19 but is present at one level.

(289) The conductor separation element 600 may e.g. be made of sheets of metal or other and be secured or welded to the main structure of the wellhead platform.

(290) This may advantageously be placed near the well template located on the seabed or at relatively lower levels.

(291) For a particular use, the respective conductor separation elements 600 of FIGS. 19 and 20 may be used together (e.g. at different levels).

(292) FIG. 21 schematically illustrates a conductor running from the seabed to above the sea-level together with indications of locations of various support elements.

(293) Shown schematically is a seabed 120 and a water level 110 where a conductor 210 is run from (below) the seabed 120 to above the water level 110 to a configurable support structure of an offshore wellhead platform (not shown; see e.g. 200 and 100 in other figures) e.g. as has been disclosed elsewhere.

(294) The conductor 210 is shown in two positions. One indicated with a full line and one indicated with a broken line. The upper part of the conductor is moved, as explained elsewhere, between these two positions (either way) (and potentially between other positions) where one position may be a second position and the other may be a first (or third compensation) position.

(295) Only a single conductor 210 is shown for clarity (more will generally be present) and the extent of movement of the upper part of the conductor is exaggerated.

(296) Further indicated is a lower circle 701 near or at a seabed well template, an upper circle 703 near the wellhead deck or other deck, and a middle circle 702 in between the two other circles. Please note the circles are approximate positions, e.g. the middle circle 702 may e.g. cover everything in between the lower and upper circles 701, 703.

(297) The circles represent expedient areas to have one or more of the various support elements as disclosed elsewhere in place.

(298) At the lower circle 701, one or more support elements as shown in FIG. 22, one or more (preferably passive or fixed) of the conductor guides 501 and restriction elements 520 as shown in FIGS. 11a, 11b, 12a, 12b, 13a-13c, 14, 16 may be used to effect.

(299) At the middle circle 702, one or more support elements like one or more (preferably passive or fixed) of the conductor guides 501 and restriction elements 520 as shown in FIGS. 11a, 11b, 12a, 12b, 13a-13c, 14, 16 may be used to effect.

(300) At the upper circle 703, one or more support elements like one or more (passive and/or active) of the conductor guides 501 and restriction elements 520 as shown in FIGS. 11a, 11b, 12a, 12b, 13a-13c, 14-16, one or more of the cable anchoring system 550 or similar as shown in FIGS. 17-18, and the mechanism for moving a conductor and a locking mechanism as shown in FIG. 23 may be used to effect.

(301) In particular, a conductor guide with conductor positioning elements (e.g. as shown in FIGS. 15 and 16), the mechanism for moving a conductor and a locking mechanism as shown in FIG. 23, and a cable anchoring system (e.g. as shown in FIGS. 17 and 18) may be used to effect.

(302) FIG. 22 schematically illustrates an exemplary double-conductor guide according to some embodiments of the present invention that may be particularly suited for a seabed well template. As discussed elsewhere it is often advantagous that the conductor is substantially fixed at or near the seabed. Applied at our near the seabed the configuration shown in FIG. 22 may be used as an alternative.

(303) Shown is a double-conductor guide 505 e.g. comprising two conductor guides 501 e.g. as shown in FIGS. 11a and 11 b with the following differences. Each individual conductor guide 501 comprises two (one on each generally opposing side) rotatable joint-and-socket elements 545 or similar secured to the main structure of the wellhead platform. The two conductor guides 501 together forming the double-conductor guide 505 are located in relation to each other with one being substantially above the other (as shown).

(304) This provides the advantage that when a conductor 210 is moved in a particular direction as already explained, the resulting stress is distributed generally or mainly at two areas—one area at one conductor guide and another area at the other conductor guide—in two generally opposite directions. As an example if the conductor is moved to the left (left in the drawing), the stress will generally or mainly be distributed at the two areas designated 900. In this way, it is ensured that the resulting stress or force is distributed and not being limited to one point or a single area.

(305) The rotatable joint-and-socket elements 545 or similar enable a respective conductor guide 501 to tilt to some extent. Additionally, the joint-and-socket elements 545 or similar will also generally restrict movement to along one direction—providing guidance—but allowing for some tilting in a general direction orthogonal to the general allowed direction.

(306) Such double-conductor guides 505 are particularly suited for a seabed well template that e.g. could comprise a plurality of double-conductor guides 505 (see e.g. 505 in FIGS. 3 and 8).

(307) Corresponding triple-conductor guides, and so on for certain designs and/or uses could also be contemplated.

(308) FIG. 23 schematically illustrates another embodiment of a suitable mechanism for moving an upper part of a conductor between its first position and its second position and a locking mechanism for securing an upper part of a conductor at its second position.

(309) Shown is a configurable support structure 200 (only the relevant horizontal section is shown) as described elsewhere comprising a number (here eight as an example) of first and a number (here one as an example) of second positions 150, 160, a number of conductors 210, a mechanism (as represented by arrow 537) for moving an upper part of a conductor between its first position and its second position, and a locking mechanism 536 for securing and retaining an upper part of a conductor 210 at is second position 160.

(310) The left figure illustrates a conductor 210 having its upper part moved from its first position 150 to a central second position 160 and being secured while the right figure illustrates the upper part of the conductor 210 after the move and when being in a secured state.

(311) In some embodiments, the suitable mechanism for moving a conductor pushes the upper part of the conductor and in some alternative embodiments the suitable mechanism for moving a conductor pulls the upper part of the conductor, and/or a combination thereof.

(312) In some embodiments, the locking mechanism 536 is rotatable or movable around the central second position 160 and comprises a central cavity for receiving an upper part of a conductor (e.g. including some extra space) where the central cavity is accessible by a slot or similar only from one general direction (at least big enough to allow passage of an upper part of a conductor plus some additional space) and closed at other directions. In some embodiments, the locking mechanism 536 has a shape generally being a C- or U-shape. This readily enables locking simply by turning the locking mechanism 536 once the conductor is in the central cavity.

(313) In some embodiments, the suitable mechanism for moving an upper part of a conductor is rotatable or movable around the central second position 160 whereby only a single mechanism is required for moving upper parts of conductors from all first positions (when placed around a central second position).

(314) When the upper part of the conductor is to be moved from the second position to a first position, the locking mechanism 536 is simply rotated or moved so the slot or similar faces the direction towards the first position the conductor is to be moved to (same or different first position than the one it came from) and the suitable mechanism for moving may apply a push or pull force in the appropriate direction.

(315) FIG. 24 schematically illustrates a configurable support structure and an alternative arrangement for moving a conductor.

(316) Illustrated is at least a part of a configurable support structure 200, e.g. corresponding to the one shown in FIG. 5 or similar, and a conductor moving system 550 for selective movement of an upper part of a conductor 210 between first and second positions 150, 160 where the conductor moving system 550 may form part of at least one support element.

(317) Further shown are a number of conductors 210, a number of first positions 150, and a number of shared second positions 160 where the configurable support structure 200 corresponds—at least in function—to configurable support structures as described elsewhere. This particular exemplary configurable support structure 200 provides eight first positions 150 located outside a working center zone 250 wherein one shared second position 160 is arranged according to a specific arrangement. The exemplary shape of the working center zone 250 is rectangular with two shorter sides.

(318) The illustrated conductor moving system 550 comprises a number of individual conductor movement mechanisms 710, 710′. In the illustrated and corresponding embodiments, the conductor moving system 550 comprises ten conductor movement mechanisms 710, 710′ being, as an example, of two types; eight of a first type and two of a second type.

(319) The mechanisms of the first type 710 are arranged so that each first position 150 has one particular first type mechanism 710 associated with it. The mechanisms of the first type 710 are each responsible for moving an upper part of one conductor from a first position 150 into the working center zone 250 and moving the upper part of the conductor back again from the working center zone 250 to its or a first position 150. Accordingly, the mechanisms of the first type 710, in some embodiments, need only to be able to move an upper part of a conductor only along one direction, i.e. with one degree of freedom, but back and forth.

(320) A conductor moving mechanism of the first type 710 may be any mechanism that can push and pull the upper part of a conductor along one direction. Such mechanisms can be fairly simple. As a specific example, the conductor moving mechanism of the first type 710 may e.g. be of the piston type. The conductor moving mechanism of the first type 710 can alternatively be more complex and capable, and e.g. be capable of moving an upper part of a conductor in one or more desired directions.

(321) The mechanisms of the second type 710′ are responsible for moving an upper part of a conductor located somewhere in the working center zone 250 to the shared second position 160 (or to one or more if several shared second positions are arranged in the working center zone 250).

(322) In some embodiments, the mechanisms of the second type 710′ are capable of moving the upper part of a conductor 210 with two degrees of freedom (X-Y) as this allows for precise placement of the upper part of a conductor at a (shared) second position 160.

(323) A conductor moving mechanism of the second type 710′ may be any mechanism that can push and pull the upper part of a conductor with two degrees of freedom (X-Y). As a specific example, the conductor moving mechanism of the second type 710′ may e.g. also be of the piston type, but will generally be more complex than the conductor moving mechanism of the first type 710.

(324) In the shown exemplary embodiment, the conductor moving mechanisms of the second type 710′ are located at the shorter sides of the rectangular working center zone 710.

(325) The moving mechanisms (of both types) are e.g. each adapted to secure an upper part of a conductor to it during movement. They may e.g. be circular (instead of fork-shaped as shown) with an opening for receiving an upper part.

(326) Illustrated in FIG. 24 is a conductor moving mechanism of the first type 710 moving an upper part of a conductor 210 into the working center zone 250 as indicated by the arrow. The originating first position is shown as a hatched circle and the starting position of the conductor moving mechanisms of the first type 710 responsible for moving the upper part of the conductor 210 is shown as a dashed conductor moving mechanism. Now only remains, for a conductor moving mechanisms of the second type 710′ to position the upper part of the conductor 210 at the (shared) second position 160.

(327) This readily allows for precise and controlled movement of an upper part of a conductor 210 between first and second positions 150, 160 in a working center zone 250.

(328) In some embodiments, the first and second types of moving mechanism 710, 710′ are working at different height levels as this reduces the risk of collision.

(329) In some embodiments, only one mechanism of the second type 710′ is used instead of two, then e.g. located at either of the shown locations. In some further embodiments, a single mechanism of the second type 710′ is able to be moved e.g. between the two sides of the working center zone 250 as shown to have a mechanism of the second type 710′.

(330) FIGS. 25a and 25b schematically illustrates another embodiment of a configurable support structure.

(331) Illustrated in FIG. 25a is at least a part of a configurable support structure 200 providing a number of first positions 150 and a number of shared second positions 160 where the configurable support structure corresponds to configurable support structures as described elsewhere. This particular exemplary configurable support structure 200 comprises one shared second position 160 and four first positions 150 arranged according to a particular arrangement where four conductors 210 are shown in the first positions 150 passing through the configurable support structure 200. The configurable support structure 200 corresponds—at least in function—to configurable support structures as described elsewhere.

(332) Apart from the number of first positions and the particular layout it corresponds to e.g. the configurable support structure of FIG. 2.

(333) The configurable support structure 200 may e.g. be part of or comprised by a suitable deck, e.g a wellhead deck as shown as 101 in FIGS. 3 and 8a-b or any other suitable deck or structure located at a plane being in proximity of the upper parts of conductors once supported or engaged by the wellhead platform.

(334) In addition to such a configurable support structure 200, the wellhead platform may e.g. comprise one or more additional structures located closer towards the seabed, e.g as shown in FIG. 25b. This structure may be seen as a (distinct or separate) part of the configurable support structure 200, as another configurable support structure, or as a configurable support structure-like structure.

(335) The shown exemplary structure 200′ of FIG. 25b also provides a number of first positions (equal to the number of first positions of the configurable support structure 200 of FIG. 25a) and a number of second positions 160 (here four instead of one as in FIG. 25a). The second positions 160 here are not shared or coinciding.

(336) As can be appreciated, the respective conductors 210 (at this level) will be in the respective second positions (not coinciding) when the upper part of the respective conductors 210 are at the shared second position at the level of the configurable support structure 200 of FIG. 25a. This is due to i) the different levels of the two structures 200 200′, ii) that the conductors are fixed at least near the seabed (or potentially higher up but lower than the level of this structure 200′), iii) that the conductors are fixed into the seabed with distance between them, and iv) coincide at the shared second position defined by the upper level of the configurable support structure 200 of FIG. 25a.

(337) The structure 200′ allows movement of the conductors 210 at its particular level when the respective upper parts of the conductors 210 are moved between their first and second positions.

(338) The structure 200′ may e.g. be combined with one or more certain conductor support element(s) as mentioned elsewhere.

(339) It should be understood that certain embodiments or aspects of the different figures may be combined to effect while certain embodiments or aspects also may be used independently of other.

(340) In some embodiments throughout the specification, the at least one support element comprises at least one locking element or mechanism adapted to selectively fixate a movable conductor guide in a horizontal plane and in relation to the main structure of the wellhead platform where the movable conductor guide is adapted to receive a part of a conductor. This/these may be used together with all other applicable mentioned embodiments.

(341) FIGS. 26a-d schematically illustrate another embodiment of an offshore wellhead platform with conductors in their respective first positions. In particular, FIG. 26a shows a front view of the platform while FIGS. 26b-d show cross sections along lines C-C, B-B and A-A in FIG. 26a, respectively. Similarly, FIG. 27a shows a front view of the platform while FIGS. 27b-d show cross sections along lines C-C, B-B and A-A in FIG. 27a, respectively

(342) The wellhead platform 100 comprises a configurable support structure including a number of support elements at different heights above the seabed 120, as will be described in more detail below.

(343) The wellhead platform 100 comprises a wellhead deck 101 (also referred to as cellar deck) an x-mas tree access deck 102 (also referred to as a production deck), and a main deck 103 (also referred to as weather deck). FIGS. 26b-d show cross sections at the weather deck level, the production deck level and the wellhead deck level, respectively.

(344) Each deck comprises two openings such that the openings of all decks define two sets of openings where the openings of each set are vertically aligned with each other so as to form a first and a second drilling center DC#1 and DC#2, respectively. This allows a dual activity rig having two working centers to efficiently cooperate with the wellhead platform 100.

(345) In particular, as can best be seen in FIG. 26a, the weather deck comprises two openings 103a/b sized and shaped to allow tubulars of a desired diameter to extend through each opening.

(346) As can best be seen in FIG. 26c, the wellhead deck comprises two larger openings 101a/b each defining a centrally located hole 160 and where the periphery of the opening includes radially outward extending slots 150 distributed along the periphery of the opening. The slots 150 of each opening define respective first positions for the upper ends of respective conductors while the central hole 160 of each opening defines a shared second position, shared by conductors positioned in the respective first positions of the corresponding opening such that the upper ends of the conductors are movable between any of the first positions and the shared second position of the corresponding opening. The two openings thus define two clusters, each cluster having a plurality of first positions and a shared second position, e.g. similar to the configuration described in connection with FIG. 4d.

(347) As can best be seen in FIG. 26d, the x-mas tree access deck comprises two larger openings 102a/b similar to the openings of the wellhead deck, i.e. each defining a centrally located hole defining a shared second position 160. The periphery of each opening includes radially outward extending slots defining respective first positions 150 distributed along the periphery of the opening. Generally, parts of the openings in the decks may be covered when not in use and/or fenced to ensure safe working conditions for people working on the deck and reduce the risk of dropped objects between decks. Covers may be in the form of hatches, grating and/or deck pieces inserted into the respective opening.

(348) The openings 101a/b and 102a/b are part of the configurable support structure and allow movement of the upper parts of the conductors 210a/b, 210a′/b′, 210a″/b″. This is illustrated in FIGS. 27a-d which show the same wellhead platform as in FIGS. 26a-d but where two conductors 210a′/b′ have been moved from their respective first positions to the corresponding shared second position.

(349) In particular, in the example of FIG. 26a-d, all first positions of both openings 101a/b (and accordingly of openings 102a/b) are occupied by respective conductors 210a/b, 210a′/b′, 210a″/b″. Conductors 210a″ and 210b″ are shown as completed with x-mas trees 420a and 420b installed. Conductors 210a″ and 210b″ are shown as substantially straight in this position. By comparison conductors 210a and 210b are installed in an S-shape when completed with their upper end in their respective first positions as shown in FIG. 27e. In the example of FIGS. 27a-d, one conductor 210a″ has been moved from its first position in opening 101a to the central shared second position 160 of opening 101a (and correspondingly for opening 102a). Hence, the upper end of the conductor 210a″ is now aligned with the hole 103a in the weather deck and with the drilling center DC#1 such that a drilling station aligned with drilling center DC#1 can engage the conductor and perform well processing tasks in the corresponding well, e.g. via respective high-pressure risers 430. Similarly, in the example of FIGS. 27a-d, one conductor 21013′ has been moved from its first position in opening 101b to the central shared position of opening 101b (and correspondingly for opening 102b) such that the upper end of the conductor 210b′ is aligned with opening 103b in the weather deck and drilling center DC#2 such that a drilling station aligned with drilling center DC#2 can engage the conductor 210b′ and perform well processing tasks in the corresponding well, e.g. via respective high-pressure risers 430.

(350) Accordingly, the conductors 210a, 210a′, 210a″ are arranged in a first cluster associated with openings 101a, 102a and 103a and the conductors 210b, 210b′, 210b″ are arranged in another cluster associated with openings 101b, 102b and 103b.

(351) In the example of FIGS. 26a-d and 27a-d, the wells of the conductors 210a″ and 210b″ have been completed and X-mas trees 420a/b and wellheads 415a/b have been installed and the conductors have been placed in their respective first positions.

(352) The decks 101, 102 and 103 of the well head platform are supported by legs 2610 or another platform support structure. The platform support structure is also referred to as main structure of the wellhead platform.

(353) As will now be described in greater detail, the configurable support structure supporting the conductors further comprise various conductor guides or other forms of support elements as well as a moving mechanism for moving the upper part of the conductors. For the purpose of illustration guides will be used as examplary support elements but other types of support elements may be applied instead:

(354) In particular, the configurable support structure comprises conductor moving mechanisms 550. In the present example, the mechanism is arranged on the wellhead deck and engages the upper part of the conductor near the well head. It will be appreciated that, in other embodiments, the moving mechanism may be provided below the wellhead deck or at a different position along the conductor. For example, by providing a longer uppermost portion of the conductor above the moving mechanism and above any conductor guide, at least when the conductor is in its second position, the uppermost portion may be allowed to bend/flex when connected to a drilling station, e.g. so as to allow for relative movements of the drilling station and the wellhead platform. The moving mechanism 550 may directly or indirectly be connected, e.g. hinged, to the main structure of the wellhead platform, e.g. to the wellhead deck, such that e.g. thermal expansions are decoupled. Examples of moving mechanisms are described in connection with FIGS. 17, 18, 24 and 28a-c. In some embodiments separate moving mechanisms may be provided for each conductor while, in other embodiments, fewer moving mechanisms may be provided that can selectively move different conductors.

(355) The configurable support structure further comprises a number of conductor guides 2671, 2672, 2673. The conductor guides are attached directly or indirectly to the legs or to another part of the main structure of the wellhead platform.

(356) In particular, the conductor guides include upper guides 2671 that are arranged below the wellhead deck and above the water level. The upper guides are movable and may comprise an actuator or other moving mechanism for moving the conductor. For example, the conductor guides 2671 may directly or indirectly be connected to the main structure via hydraulic cylinders that can be controlled to reposition the conductor guides relative to the legs. In particular, the upper guides 2671 and the moving mechanism may cooperate so as to maintain the upper part of the conductor substantially vertical even when the upper end of the conductor is moved to another position, e.g. when the conductor is positioned at the second position so as to facilitate proper engagement of the drilling station with the conductor. In this case this results in conductors 210a′ and 210b′ following an S-shape. It will be appreciated that, in other embodiments, the conductor guide 2671 may be positioned above the moving mechanism 550, e.g. by placing the conductor guide 2671 above the wellhead deck and the moving mechanism below the wellhead deck. For example, when the conductor guides 2671 are located above a lowest deck of the wellhead platform they may be easier to operate and maintain. A lower position may provide and increased flexibility for the x-mas tree. In such case a further guide may be used to support the conductors below the x-mas tree during the production phase.

(357) Generally, in some embodiments, two cooperating guides that engage the upper part of the conductor and that can be positioned by a suitable drive mechanism (e.g. a motor, hydraulic cylinders or the like) may be operable to control the position and orientation of the upper part and/or upper end of the conductor. Accordingly in some embodiments the platform comprises two cooperating support elements arranged to apply opposite oriented, lateral forces at respective positions along the length of the first conductor. In some embodiments, one guide that is driven by a suitable drive mechanism and one lockable guide may be sufficient.

(358) In some embodiments it may be desirable to reduce the relative motion between the conductor and the wellhead platform and between the conductor and the drilling station, as both impose forces on the well. Accordingly, the configurable control structure may comprise means for following the relative motions of the rig, e.g. dampening mechanism and/or a control system controlling the moving mechanism, e.g. based on measurements of the relative position(s) and implementing a suitable feedback loop.

(359) The conductor guides further include lower conductor guides 2673 arranged at or at least near the seabed. The conductor guides 2673 are preferably horizontally fixed at a position above the position where the conductor projects into the seabed. The lower conductor guides 2673 are formed as two or more guides distributed along a lower portion of the conductor up to a suitable height above the seabed, so as to avoid bending stresses to be transferred to the part of the conductor that is submerged in the seabed when the upper part of the conductor is horizontally displaced. The lower guides serve to isolate the movement of the upper parts of the conductors from the parts of the conductors that extend into the seabed and so as to ensure integrity of the cement below the seabed. For example, the lower conductor guides may be formed as the guides shown in FIGS. 11a-b (in some instances without a lower funnel towards the seabed as the conductor may preferably be static here regardless of movements of the upper end), as a frame, grid or template, or another suitable support structure. In some embodiments, the lower conductor guides 2673 for each conductor may comprise or be formed as a single, elongated guide of a suitable length. As can best be seen in FIG. 27a, the lower conductor guides may cause the conductor to remain substantially straight along a lower portion immediately above the seabed. Suitable forms of lower conductor guides include a rigid tubular guide where the upper end is funnel-shaped with upwardly increasing diameter so as so avoid sharp edges as the conductor bends.

(360) In many embodiments it may be desirable to minimize the horizontal spacing between the lower guides. In some embodiments, the lower guides are distributed (e.g. circularly arranged) around the projection of the second position. The lower guides may be arranged in a honeycomb grid or a square matrix. In some embodiments, a lower guide may also be positioned in alignement with the shared second position of the upper ends e.g. to support the last conductor to installed straight in the second position.

(361) The conductor guides further include intermediate support elements in the form of conductor guides 2672 arranged at one or more intermediate heights between the lower and upper conductor guides. The intermediate support elements provide lateral support to the conductors and they decouple harmonic vibrations to reduce wave fatigue. They may assist maintaining the conductors in a suitable shape, e.g. to manage bending stresses, and they may help to reduce the risk of conductors colliding with each other or with other parts of the wellhead template. The intermediate support elements may fix the position of the conductor to a single position, e.g. by employing conductor guides of the type shown in FIGS. 11a-b or they may restrict horizontal movement of the conductor, e.g. to a certain horizontal distance and/or a certain direction, e.g. by employing conductor guides as shown in FIG. 13a-c or 14-16.

(362) In some embodiments, no intermediate support elements may be necessary at all while other embodiments may use one or more different types of support elements, e.g.: “slot guides” i.e. a restricting movement to one direction e.g. between two beams, such as transverse to the general direction of the water current. passive restraints e.g. by means of springs, pistons or friction either directly imposed on the conductors or via a guide. locking elements such as a mounted so that it may e.g. move with the conductor but be locked at a position so as to impose a shape as the conductor is moved. active support element such as guides and a movement mechanism that actively push or pull the conductor, e.g. by means of hydraulics, a chain to the surface or by a local electrical/mechanical motor.

(363) Intermediate conductor guides may be rotatable around one or more horizontal axes so as to reduce local loads imposed by the guide onto the conductor.

(364) In the example of FIGS. 26a-d and 27a-d, all intermediate support elements are located below the water level. In alternative embodiments, further intermediate support elements may be desirable above the water level. In any event, when the intermediate support elements are located outside the splash zone, the risk of damage and increased wear is reduced.

(365) In the embodiments of FIGS. 26a-d and 27a-d the x-mas trees are all positioned on the same deck. It will generally be appreciated that, in some embodiments some x-mas trees may be located on an upper deck while other x-mas trees may be positioned on a lower deck, e.g. in an alternating fashion, as this may allow the conductors to be moved closer together while, at the same time providing sufficient space for the x-mas trees. In some embodiments this means that the wellhead platform comprises an upper and lower production deck and/or an upper and lower wellhead deck. One or more of these decks may be structural decks or mezzanine decks.

(366) FIGS. 28a-c schematically illustrate different embodiments of moving mechanisms for use with the embodiment of FIGS. 26a-d and 27a-d. In particular, in each of the figures, the left part of the drawing shows opening 101a in the situation of FIGS. 26a-d, i.e. in a situation where all conductors are in their first positions while the right part of each drawing illustrates opening 101a in the situation of FIGS. 27a-d, i.e. in a situation where one conductor 210a′ has been moved to the central shared position. FIG. 28a shows how this movement may be implemented with a moving mechanism as described in FIGS. 17 and 18 using a cable anchoring system with e.g. three anchor points. FIG. 28b shows how this movement may be implemented with a moving mechanism as described in FIG. 16 using two hydraulic cylinders. FIG. 28c shows how this movement may be implemented with a moving mechanism as described in FIGS. 12a-b using a single hydraulic cylinder.

(367) FIGS. 29a-c schematically illustrate embodiments of support elements of a configurable support structure. In particular FIGS. 29a-c show horizontal cross sections of a wellhead platform 100 similar to the wellhead platform of FIG. 26a. The wellhead platform comprises a main structure 510 including legs 2610. FIG. 29a shows a cross section through the wellhead deck 102. The deck has two deck sections 2902a and 2902b that each define an opening 102a and 102b, respectively, as described in connection with FIGS. 26a-d. FIG. 29b shows a cross section at a lower level where the configurable support structure comprises intermediate conductor guides 2672, e.g. of the type shown in FIGS. 11a,b or of another suitable type. Finally, FIG. 29c shows a cross section just above the seabed where the configurable support structure comprises templates 2673 for fixing the position of the lower ends of the part of the conductors that extend above the seabed.

(368) FIG. 27e shows the wellhead platform and the conductors 210 of FIG. 26 where the upper ends of the conductors 210a and 210b have been returned to their respective first positions. As explained above, the conduits installed in the conductors (e.g. casing cemented in place) may introduce resistance to revert to the initial straight state. Accordingly, it may be optimal to allow the conductor to be curved as the upper end is positioned in the first position. Optimum may e.g. be in a minimum bending stress. The wells comprising the conductors 210a″/b″ are shown completed with x-mas trees 420a/b with straight conductors above the seabed for comparison. In co-pending application UK1607182.1 describes modifications to the normal method of cementing casings inside the conductor such as omitting the cement above the seabed or the introduction of weak spots or zones in cement above the seabed improve flexibility of the well above the seabed or parts thereof and/or control of breaking. While shown here as straight for illustration purposes, inventions of UK1607182.1 may been employed to allow 210a″/b″ to be straight or the configuration and/or function of these wells may allow some conductors to be straight subsequent to completetion whereas other should be allow to curve.

(369) FIG. 30 schematically illustrates an embodiment of a coupling element for coupling a wellhead to a x-mas tree. In some embodiments of the wellhead platform, the upper part of the conductor may be inclined relative to the vertical axis when moved to the first or second position. However, it may be desirable to maintain the x-mas tree in an upright position. To this end, in some embodiments, the well head platform may employ multiple cooperating conductor guides and moving mechanism that together control not only the position of the upper end of the conductor but also the inclination of the upper part, e.g. as described in connection with FIGS. 26a-d and 27a-d. However, other embodiments may not have such cooperating guide members or a complete control of the inclination may not be possible or desirable, e.g. due to bending constraints. To this end an aspect of the present invention relates to a coupling element 3001 as illustrated in FIG. 30 may be employed. On the bottom of FIG. 30, an example of a coupling element 3001 is shown on its own and, on the top of the drawing, the coupling element is shown in use as part of a well. The coupling member 3001 is an angled tubular that has a first end connectable to the x-mas tree 3004 and a second end connectable to the top of the well head 3005. Accordingly the respective ends of the coupling element may comprise connectors 3002 and 3003 adapted for attachment to the wellhead 415 and the x-mass tree 420, respectively. This angle may for example be larger than 1 degree, such as larger than 2 degrees, such as larger than 3 degrees, such as larger than 4 degrees, such as larger than 5 degrees such as larger than 6 degrees, such as larger than 7 degrees, such as larger than 8 degree, such as larger than 9 degrees, such as larger than 10 degrees and in some embodiments the angle is less than 90 degrees, such as less than 45 degrees, such as less than 30 degrees, such as less than 20 degrees. The connectors may be a female and a male connector, respectively. The coupling element 3001 further comprises a curved or angled tubular portion 3006 configured such that the x-mas tree is oriented upright when connected via the coupling element 3001 to a wellhead 415 mounted on the upper end of a tubular 3010 that extends out of an inclined conductor 210. To this end the coupling element may be bent/curved by an angle matching the angle of inclination of the upper part of the conductor. For example, the coupling element may comprise a piece of pipe having at its one end (in use the top end) a connector similar to the top of the wellhead and, at its other end (in use the bottom end) a connector similar to the bottom the Xmas tree. The pipe section can merely be seen as an extension of any of the two components, and may be made of the same material grade as the other two items. In the example of FIG. 30, the conductor extends through a conductor guide 2671 in an opening of the wellhead deck 101 or cellar deck.

(370) Some preferred embodiments have been shown in the foregoing, but it should be stressed that the invention is not limited to these, but may be embodied in other ways within the subject matter defined in the following claims.

(371) Furthermore, the embodiments of the invention are further described in the enclosed set of items:

(372) 1. An offshore wellhead platform (100) comprising a configurable support structure (200) for supporting

(373) an upper part of one or more conductors (210) through which one or more well processing tasks can be performed,
wherein the configurable support structure (200) provides a first position (150) and a second position (160) for the upper part of said one or more conductors (210), and the offshore wellhead platform (100) allows movement the upper part of the one or more conductors (210) between the first (150) and second position (160).
2. The offshore wellhead platform (100) according to item 1, wherein the second position (160) of at least some, e.g. all, of the plurality of conductors (210) are the same and wherein the first position (150) of at least some, e.g. all, of the plurality of conductors (210) are different at least for some of the plurality of conductors (210).
3. The offshore wellhead platform (100) according to any one of items 1-2, wherein the first position (150) of a conductor (210) is at least one member selected from the group of a parking, a storage, an injection, a well intervention, and/or a production position and the second position of the conductor (210) is a well processing and/or drilling position.
4. The offshore wellhead platform (100) according to any one of items 1-3, wherein the offshore wellhead platform (100) comprises at least one mechanism for moving or deflecting an upper part of a conductor (210) between its first position (150) and its second position (160).
5. The offshore wellhead platform (100) according to any one of items 1-4, wherein a substantially minimum bending stress state of a conductor (210) is at a predetermined position for the conductor (210) that is located between the first and the second position of the conductor (210), located substantially at the second position of the conductor (210), or located substantially at the first position of the conductor (210).
6. The offshore wellhead platform (100) according to any one of items 1-5, wherein the plurality of conductors (210) are arranged or organized in at least one cluster (600).
7. The offshore wellhead platform (100) according to any one of items 1-6, wherein the plurality of conductors (210) are arranged or organized in at least two clusters (600), wherein each cluster (600) provides at least one first position (150) and at least one second position (160) and wherein each cluster (600) is associated with its own at least one well processing station or drilling station (410) of an offshore well processing system (400).
8. The offshore wellhead platform (100) according to item 7, wherein two or more clusters (600) are connected to allow a conductor (210) to be moved between a number of clusters (600).
9. The offshore wellhead platform (100) according to any one of items 1-8, wherein at least some of the plurality of conductors (210) are arranged or organized in at least one cluster (600) comprising at least two second positions (160).
10. The offshore wellhead platform (100) according to any one of items 1-9, wherein a plurality of first (150) positions and one or more second positions (160) are arranged or organized in a predetermined pattern or arrangement where the second position(s) (160) is/are located substantially centrally and the first positions (150) are located around the second position(s) (160) in a substantially circular or oval pattern.
11. The offshore wellhead platform (100) according to any one of items 1-10, wherein the first positions (150) are located so that a first position (150) has a substantially same distance to its immediate neighbors if the plurality of conductors are arranged or organized in a single or no group or cluster, or the first positions (150) are located so that a first position (150) of a cluster (600) has a substantially same distance to its immediate neighbors of the cluster if the plurality of conductors are arranged or organized in two or more clusters (600).
12. The offshore wellhead platform (100) according to any one of items 1-9, wherein the plurality of conductors (210) are arranged or organized in at least one cluster (600) comprising a plurality of first positions (150) and at least one second position (160) wherein at least one second position (160) is located substantially centrally and at least one first position (150) is located at a first side of the second position (160) and at least one other first position (150) is located at a second side of the second position (160) being different from, e.g. opposing, the first side.
13. The offshore wellhead platform (100) according to any one of items 1-9, wherein the plurality of conductors (210) are arranged or organized in at least one cluster (600) comprising a plurality of first positions (150) and at least one second position (160) wherein at least one second position (160) is located substantially centrally and wherein a first part of the plurality of first positions (150) has a substantially same first distance to a second position (160) and wherein a second part of the plurality of first positions (150) has a substantially same second distance to the second position (160) where the first distance is different to the second distance.
14. The offshore wellhead platform (100) according to any one of items 11-13, wherein the offshore wellhead platform (100) provides a plurality of clusters (600) according to any one of items 11-13.
15. The offshore wellhead platform (100) according to any one of items 1-14, wherein the configurable support structure (200) comprises one second position (160) and four, six, eight, nine, ten, or twelve first positions (150).
16. The offshore wellhead platform (100) according to any one of items 1-15, wherein the offshore wellhead platform (100) further comprises one or more blow-out-preventer components or units to which one or more wells may be connected.
17. The offshore wellhead platform (100) according to any one of items 1-16, wherein the conductors (210) are steel pipes.
18. The offshore wellhead platform (100) according to any one of items 1-17, wherein at least a part of the upper part of one or more conductors (210) are flexible or comprises a part or segment made of a more flexible material.
19. The offshore wellhead platform (100) according to any one of items 1-18, wherein the offshore wellhead platform (100) comprises a working center zone (250) defining an opening of the offshore wellhead platform (100), where the working center zone (250) comprises an offset zone (230) to accommodate for tolerances when positioning an offshore well processing system to work on the wells of the configurable support structure (200), e.g. where the working center zone (250) is enlarged by an additional safety zone (235) to safely accommodate any effects of weather on equipment during well construction.
20. The offshore wellhead platform (100) according to any one of items 1-19, wherein the configurable support structure (200) provides a single first position (150) and a single second position (160).
21. The offshore wellhead platform (100) according to any one of items 1-20, wherein the configurable support structure (200) comprises one or more further conductors without a first and/or a second position (150, 160).
22. A method of constructing and/or processing one or more offshore surface-wells (300), the method comprising constructing and/or processing an offshore surface-well (300) from a working or drilling center position, said method comprising the steps of 1. at least partially constructing and/or processing one of the one or more surface-well (300) through a conductor (300) at the working or drilling center position (160), 2. moving an upper part of the conductor (300) to a first position (150), and 3. producing from or injecting into the surface-well (300) through the conductor (300) at the first position (150).
23. The method according to item 22, wherein the working or drilling center position is a second position (160) and wherein the second position (160) of at least some, e.g. all, of a plurality of conductors (210) of a plurality of surface-wells (300) is the same and wherein the first position (150) of at least some, e.g. all, of the plurality of conductors (210) of surface-well (300) are different at least for some of the plurality of conductors (210).
24. The method according to item 22 or 23, wherein the method comprises progressing a plurality of surface-wells (300) towards completion by moving an upper part of a conductor (210) from a first position (150) to a second position (160) and carrying out one or more well constructing and/or processing tasks to complete the surface-well (300) of the conductor (210), moving an upper part of the conductor (210) to a first position (150) after completion, and repeating these steps for one or more additional conductors (210).
25. The method according to any one of items 22-24, wherein the method comprises progressing a plurality of surface-wells (300) towards completion by moving an upper part of a conductor (210) from a first position (150) to a second position (160) and carrying out at least one well constructing and/or processing task and/or sub-task, moving an upper part of the conductor (210) from the second position (160) to a first position after completion of the at least one well constructing and/or processing task and/or sub-task, repeating these steps for a desired number of conductors (210), and when the at least one well constructing and/or processing task and/or sub-task have been completed for all the desired number of conductors (210) then repeating the steps again for at least one next well constructing and/or processing task and/or sub-task until all desired constructing and/or processing task and/or sub-task have been carried out for all desired conductors (210).
26. The method according to any one of items 22-25, wherein the method comprises performing concurrent or parallel drilling or well processing on at least two wells (300) located at separate second positions (160).
27. The method according to any one of items 22-26, wherein the method comprises performing constructing and/or processing on a well (300) located at a first second position (160), followed by moving an upper part of the well (300) to a second second position and performing drilling or well processing on the well (300) when located at the second second position (160).
28. The method according to any one of items 22-27, wherein the method comprises constructing and/or processing at least one well (300) through a working center zone (250) and then moving the working center zone (250) and then constructing and/or processing at least one well (300) through the moved working center zone (250).
29. The method according to any one of items 22-28, wherein the method comprises constructing and/or processing at least one well (300) at at least one second position (160) at a working center zone (250) and after a number of wells (300) have been completed and/or processed and moved to respective first positions (150) outside the working center zone (250) then constructing and/or processing at least one well (300) in the working center zone (250) at or near the at least one second position (160).
30. An offshore well processing system (400) for performing one or more well processing tasks on a plurality of surface-wells (300) of one or more off-shore reservoirs located below the seabed (120) wherein the offshore well processing system (400) comprises or works together with an offshore wellhead platform (100) according to any one of items 1-21 and comprises one or more drilling units or derricks (410).
31. The offshore well processing system (400) according to item 30, wherein the offshore well processing system (400) comprises at least one mechanism for moving an upper part of a conductor (210) between a first position (150) and a second position (160).
32. The offshore well processing system (400) according to item 30 or 31, wherein the offshore well processing system (400) is a jack-up unit.
33. The offshore well processing system (400) according to any one of items 30-32, wherein the offshore well processing system (400) further comprises one or more blow-out-preventer components or units to which one or more wells may be connected.
34. The offshore well processing system (400) according to any one of items 30-33 wherein the offshore well processing system (400) comprises at least two well processing stations or drilling stations (410), wherein the well processing stations or drilling stations (410) are capable of operating fully independently of each other.
35. The offshore well processing system (400) according to item 34, wherein each of the at least two well processing stations or drilling stations (410) comprises its own fluid system and well control system.
36. Use of the offshore wellhead platform (100) according to any one of items 1-21 to perform batch-drilling.

(374) In some embodiments, the configurable support structure for supporting an upper part of a plurality of conductors may itself also be movable and/or rotatable.

(375) It is to be noted that the number of first positions of a configurable support structure may be uneven even though only an even number of first positions are shown in the figures.

(376) In the claims enumerating several features, some or all of these features may be embodied by one and the same element, component or item. The mere fact that certain measures are recited in mutually different dependent claims or described in different embodiments does not indicate that a combination of these measures cannot be used to advantage.

(377) It should be emphasized that the term “comprises/comprising” when used in this description is taken to specify the presence of stated features, elements, steps or components but does not preclude the presence or addition of one or more other features, elements, steps, components or groups thereof. However, on the other hand the term “comprises/comprising” is intended to also include embodiments where the particular articles is formed entirely by the comprised features.