Vessel and method to perform subsea wellbore related operations

Abstract

A vessel and method to perform subsea wellbore related operations, e.g. slim hole technique drilling of a subsea wellbore are disclosed. The vessel has a hull with at least one moonpool defining first and second moonpool areas. A vertical tower is mounted on a tower supporting hull structure and has a vertical operative face. A hoisting device has a winch and winch driven cable, and is adapted to suspend a load from said vertical tower via said at least one winch driven cable and to manipulate the suspended load in a firing line of the tower that extends along and outside of said vertical operative face of the tower. The tower is slewable about a vertical slew axis by means of a slewing drive at least into first and second operative positions wherein the firing line extends through the first and second moonpool areas respectively.

Claims

1. A vessel adapted to perform subsea wellbore related operations, said vessel comprising: a floating hull comprising a tower supporting hull structure; at least one moonpool in said hull defining at least a first moonpool area; a vertical tower configured to perform subsea wellbore related operations, the vertical tower being mounted on said tower supporting hull structure, said vertical tower having a vertical operative face; and a hoisting device comprising at least one winch and at least one winch driven cable, the hoisting device being adapted to suspend a load from said vertical tower via said at least one winch driven cable and to manipulate said suspended load in a firing line of the tower that extends along and outside of said vertical operative face of the tower, wherein the at least one moonpool of the vessel is embodied to further define a second moonpool area that is offset from said first moonpool area, and wherein the vertical tower is connected to the tower supporting hull structure via one or more slew bearings and the vessel is provided with a slewing drive, such that the vertical tower is slewable about a vertical slew axis by means of said slewing drive at least into a first operative position wherein the firing line of the tower extends through the first moonpool area and into a second operative position wherein the firing line of the tower extends through the second moonpool area.

2. The vessel according to claim 1, wherein the first and second operative positions of the tower are diametrically opposite the slew axis.

3. The vessel according to claim 1, wherein said tower supporting hull structure extends in between said first and second moonpool areas.

4. The vessel according to claim 1, wherein said hull is a monohull having a longitudinal axis, and wherein said first and second moonpool areas are offset in the direction of said longitudinal axis, wherein said tower supporting hull structure extends substantially in transverse direction of the hull and in between said first and second moonpool areas.

5. The vessel according to claim 1, wherein the vessel has a deck and wherein the first and second moonpool areas are defined by offset first and second moonpool openings in the deck.

6. The vessel according to claim 1, wherein the vessel has distinct first and second moonpools, each extending between a respective first and second moonpool opening in a deck of the vessel to a respective lower opening in a bottom of the hull.

7. The vessel according to claim 1, wherein the vessel has a single moonpool with the tower supporting hull structure being embodied as a bridge over a central area of the moonpool, said bridge above the design waterline of the vessel, wherein the first and second moonpool areas are located an opposite sides of the tower supporting hull structure and each defined by a respective first and second moonpool opening in a deck of the vessel.

8. The vessel according to claim 1, wherein the tower has a foot, and wherein at least one slew bearing is arranged between said foot of the tower and the tower supporting hull structure.

9. The vessel according to claim 1, wherein the tower is provided at said operative side with one or more vertical guide rails, and wherein a travelling device is provided that is movable up and down along and outside of said operative side of the tower and guided by said one or more vertical guide rails of said tower, wherein said travelling device is suspended from said winch driven cable, and wherein the travelling device is adapted to suspend a load from said travelling device, and wherein the hull of the vessel is provided, at least for one of the first and the second moonpool areas, with one or more hull mounted vertical guide rails which are arranged such that in at least one of said first and said second operative position of the tower, said guide rails of the tower align with said one or more hull mounted vertical guide rails.

10. The vessel according to claim 1, wherein the winch is mounted on the tower, and wherein the tower is provided with one or more heave compensation cylinders acting on one or more cable sheaves along which the winch driven cable passes in order to provide heave compensation functionality.

11. The vessel according to claim 1, where a top drive device is connected to the travelling device.

12. The vessel according to claim 1, wherein at least one of said first and second moonpool areas is defined by a moonpool opening in a deck of the vessel, and wherein the vessel is provided with one or more movable hatches associated with said moonpool opening, said one or more hatches in an opened position thereof clearing the moonpool opening and in a closed position thereof forming a hatch cover over the moonpool opening.

13. The vessel according to claim 12, wherein the one or more hatches associated with at least one of said first and second moonpool opening are provided with a pair of skid rails, and wherein the deck in a region adjacent the moonpool opening is provided with a pair of deck mounted skid rails, wherein, in said closed position of said one or more hatches the pair of skid rails provided thereon align with the pair of deck mounted skid rails in order to allow skidding of an object onto and off the one or more closed position hatches, and wherein the vessel is provided with a coiled tubing injector device, said coiled tubing injector device being adapted for skidding onto and off the one or more closed position hatches.

14. The vessel according to claim 13, wherein the vessel has a deck adjacent at least one of the first and second moonpool areas, and wherein a pair of skid rails are provided on which a skiddable coiled tubing reel is placed.

15. The vessel according to claim 1, wherein the vessel has deck adjacent one of the first and the second moonpool areas, and wherein a catwalk machine is arranged on said deck allowing to feed and remove drilling tubulars to and from the firing line when the tower is in the operative position thereof associated with said moonpool area.

16. The vessel according to claim 1, wherein the vessel is provided with a storage reel storing thereon a spoolable coiled tubing guide hose, and wherein the vessel is provided with a coiled tubing guide hose tensioner device having multiple tracks in a substantially vertical arrangement, which tensioner device is configured to be arranged in an operative position thereof above said first or said second moonpool area and to support the length of spoolable coiled tubing guide hose extending into the sea to subsea equipment mounted on a subsea well head.

17. A vessel adapted to perform subsea wellbore related operations, said vessel comprising: a floating monohull having a longitudinal axis, the floating hull comprising a tower supporting hull structure; at least one moonpool in said hull defining at least a first moonpool area; a vertical tower configured to perform subsea wellbore related operations, the vertical tower being mounted on said tower supporting hull structure, said vertical tower having a vertical operative face; and a hoisting device comprising at least one winch and at least one winch driven cable, the hoisting device being adapted to suspend a load from said vertical tower via said at least one winch driven cable and to manipulate said suspended load in a firing line of the tower that extends along and outside of said vertical operative face of the tower, wherein the at least one moonpool of the vessel is embodied to further define a second moonpool area that is offset from said first moonpool area in direction of said longitudinal axis, wherein the vessel has a deck, and wherein the first and second moonpool areas are defined by offset first and second moonpool openings in the deck, wherein said tower supporting hull structure extends substantially in transverse direction of the hull and in between said first and second moonpool areas, and wherein the vertical tower is connected to the tower supporting hull structure via one or more slew bearings and the vessel is provided with a slewing drive, such that the vertical tower is slewable about a vertical slew axis by means of said slewing drive at least into a first operative position wherein the firing line of the tower extends through the first moonpool area and into a second operative position wherein the firing line of the tower extends through the second moonpool area.

18. The vessel according to claim 17, wherein the vessel has a single moonpool with the tower supporting hull structure being embodied as a bridge over a central area of the moonpool, said bridge above a design waterline of the vessel, wherein the first and second moonpool areas are located an opposite sides of the tower supporting hull structure, wherein the tower has a foot, and wherein at least one slew bearing is arranged between said foot of the tower and the tower supporting hull structure.

19. The vessel according to claim 17, wherein the tower is provided at said operative side with one or more vertical guide rails, and wherein a travelling device is provided that is movable up and down along and outside of said operative side of the tower and guided by said one or more vertical guide rails of said tower, wherein said travelling device is suspended from said winch driven cable, and wherein the travelling device is adapted to suspend a load from said travelling device, and wherein the hull of the vessel is provided, at least for one of the first and the second moonpool areas, with one or more hull mounted vertical guide rails which are arranged such that in at least one of said first and/or said second operative position of the tower said guide rails of the tower align with said one or more hull mounted vertical guide rails.

20. A vessel adapted to perform subsea wellbore related operations, said vessel comprising: a floating hull comprising a tower supporting hull structure; at least one moonpool in said hull defining at least a first moonpool area; a vertical tower configured to perform subsea wellbore related operations, the vertical tower being mounted on said tower supporting hull structure, said vertical tower having a vertical operative face; and a hoisting device comprising at least one winch and at least one winch driven cable, the hoisting device being adapted to suspend a load from said vertical tower via said at least one winch driven cable and to manipulate said suspended load in a firing line of the tower that extends along and outside of said vertical operative face of the tower, wherein the at least one moonpool of the vessel is embodied to further define a second moonpool area that is offset from said first moonpool area, wherein the vertical tower is connected to the tower supporting hull structure via one or more slew bearings and the vessel is provided with a slewing drive, such that the vertical tower is slewable about a vertical slew axis by means of said slewing drive at least into a first operative position wherein the firing line of the tower extends through the first moonpool area and into a second operative position wherein the firing line of the tower extends through the second moonpool area, wherein at least one of said first and second moonpool area is defined by a moonpool opening in a deck of the vessel, and wherein the vessel is provided with one or more movable hatches associated with said moonpool opening, said one or more hatches in an opened position thereof clearing the moonpool opening and in a closed position thereof forming a hatch cover over the moonpool opening, wherein the one or more hatches are provided with a pair of skid rails, and wherein the deck in a region adjacent the moonpool opening is provided with a pair of deck mounted skid rails, wherein, in said closed position of said one or more hatches the pair of skid rails provided on said one or more hatches align with the pair of deck mounted skid rails in order to allow skidding of an object onto and off the one or more closed position hatches, wherein the vessel is provided with a coiled tubing injector device adapted for skidding over said pairs of skid rails onto and off the one or more closed position hatches, and wherein a further pair of skid rails is provided on said deck, on which a skiddable coiled tubing reel is placed.

21. The vessel according to claim 20, wherein the vessel is provided with a storage reel storing thereon a spoolable coiled tubing guide hose, and wherein the vessel is provided with a coiled tubing guide hose tensioner device having multiple tracks in a substantially vertical arrangement, which tensioner device is configured to be arranged in an operative position thereof above said first or said second moonpool area and to support the length of spoolable coiled tubing guide hose extending into the sea to subsea equipment mounted on a subsea well head.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1 shows schematically an example of a vessel to perform subsea wellbore related operations according to the invention,

(3) FIG. 2 shows schematically in plan view the deck, moonpool openings and tower of the vessel of FIG. 1 with the tower in the second operative position thereof,

(4) FIG. 3 shows schematically in plan view the deck, moonpool openings and tower of the vessel of FIG. 1 with the tower in the first operative position thereof,

(5) FIG. 4 shows schematically the tower, hull and moonpools of the vessel of FIG. 1.

DETAILED DESCRIPTION OF EMBODIMENTS

(6) With reference to FIGS. 1-4 an example of a vessel 1 adapted to perform subsea wellbore related operations will be discussed. The vessel 1 may, for example, be employed for drilling, and/or wellbore intervention operations, and/or installation of wellbore related subsea equipment.

(7) For example, the vessel 1 is considered advantageous for use with the slim hole technique drilling of a subsea wellbore. This slim hole technique is, for example and non-limiting, often defined as using equipment to drill a well that has a diameter over most, e.g. 90%, of its length of 7 inches or less. It is envisaged that this technique may be beneficial for effective exploratory drilling projects, wherein at a later stage a larger diameter actual production well can be drilled with traditional drilling equipment from a much larger drilling vessel, e.g. a vessel as in U.S. Pat. No. 6,763,898.

(8) The vessel here is, as preferred, a monohull type vessel with a hull 2 having a bow and a stern. A bridge and crew accommodation superstructure 3 is arranged on the bow. Aft of the superstructure a deck 4 extends, here all the way to the stern of the vessel.

(9) The vessels hull here is provided with two moonpools 5, 6; a front or fore moonpool 5 and a rear or aft moonpool 6. These moonpools 5, 6 each extend from a respective moonpool opening 5a, 6a in the deck 4 to a lower opening 5b, 6b in the bottom of the hull. The design waterline WL is shown in the FIG. 1.

(10) The moonpools 5, 6 are offset from one another in the direction of the longitudinal axis of the vessels hull 2.

(11) The first moonpool 5 thus defines first moonpool area, that is also denoted here with reference numeral 5. The second moonpool 6 thus defines second moonpool area, that is also denoted here with reference numeral 6.

(12) The hull 2 comprises a tower supporting hull structure 10. This structure 10 extends in between the first and second moonpools 5, 6, here from deck 4 to the level of the bottom of the hull so that the moonpools 5, 6 are completely separated.

(13) A vertical tower 20, here embodied as a closed contoured mast, is provided and is configured to perform subsea wellbore related operations.

(14) The vertical tower 20 is mounted on the tower supporting hull structure 10, so generally in between the moonpools 5, 6.

(15) The vertical tower 20 has a single vertical operative face 21, e.g. in contrast to the dual operative faces tower illustrated in U.S. Pat. No. 6,763,898.

(16) The tower 20 is provided with a hoisting device comprising at least one winch 30 and at least one winch driven cable 31. The hoisting device is adapted to suspend a load from the vertical tower 20 via the at least one winch driven cable 31 and to manipulate this suspended load in a firing line 25 of the tower 20 that extends along and outside of the vertical operative face 21 of the tower 20.

(17) In more detail the tower 20 has at a top end thereof a cantilevered tower part 24 carrying a crown block assembly 26 with one or more cable sheaves 33 for the cable(s) 31. In this example the cable 31 extends in a multiple falls arrangement between the assembly 26 and the travelling device 50.

(18) The depicted tower 20 has a square cross-section, yet other cross-sections, e.g. rectangular, hexagonal, oval, circular, etc. are also envisaged.

(19) The tower 20 may be embodied as a lattice structure, e.g. with vertical leg members and with diagonal and/or horizontal brace members, e.g. forming side walls of a further substantially hollow tower.

(20) The tower 20 may comprise one or more floors at various heights, as well as stairs leading to said floors.

(21) The vertical tower 20 is connected to the tower supporting hull structure 10 via one or more slew bearings 41, 42. Furthermore the vessel is provided with a slewing drive, here with slewing drive motors 43, 44 driving pinions that engage on a toothed ring of the tower 20.

(22) The vertical tower 20 thus is slewable about a vertical slew axis 27 by means of the slewing drive 43, 44.

(23) FIG. 3 depicts the situation that the tower 20 is in its first operative position wherein the firing line 25 of the tower 20 extends through the first moonpool area 5.

(24) FIG. 2 depicts the situation that the tower 20 is in its second operative position wherein the firing line 25 of the tower 20 extends through the second moonpool area 6.

(25) As will be appreciated, in the depicted embodiment, 2 the first and second operative positions of the tower 20 are diametrically opposite the slew axis 27.

(26) As depicted here the tower has a foot 28 and the at least one slew bearing 41, 42 is arranged between the foot 28 of the tower and the tower supporting hull structure 10.

(27) As shown here the tower is provided at said operative side with vertical guide rails 15.

(28) A travelling device 50, e.g. adapted to support a top drive device 60, is provided. The device 50 is movable up and down along and outside of the operative side 21 of the tower 20 and guided by the vertical guide rails 15 of said tower. In this example the travelling device 50 is suspended from the winch driven cable 31. The travelling device is adapted to suspend a load from the travelling device, e.g. a drilling tubulars string (drill pipe, casing) suspended from or at least attached to the top drive device 60.

(29) As can be seen in FIG. 4 the hull of the vessel is provided, here for the first moonpool area 5, with one or more hull mounted vertical guide rails 9 which are arranged such that in the first operative position of the tower 20 these guide rails 15 of the tower 20 align with the one or more hull mounted vertical guide rails 9. As shown here the one or more hull mounted guide rails 9 extend to a lower opening in a bottom of the hull.

(30) In the depicted example the winch 30 is mounted inside the closed wall contour of the tower. As explained the winch(es) 30 can also be mounted on the rear or non-operative side 22 of the tower that is opposite the operative side.

(31) It is depicted that the tower is provided with one or more heave compensation cylinders 71, 72 acting on one or more cable sheaves 73, 74 along with the winch driven cable 31 passes in order to provide heave compensation functionality.

(32) The figures also illustrate that for each of the first and second moonpool areas 5, one or more movable, e.g. horizontally slidable, hatches 81, 82, 90 are provided. These hatches, in an opened position thereof, clear the moonpool opening and in a closed position thereof form a hatch cover over the moonpool opening 5, 6.

(33) Here, the moonpool opening 5 is covered by two hatches 81, 82 that slide horizontally away and towards one another to open and close the opening 5. The mating hatch edges have a cut-out to form a well center opening 83 aligned with the firing line 25 of the tower 20 in its first position. The hatches may be embodied and used as drill floor for drilling operations.

(34) Adjacent the first second moonpool area 5 a catwalk machine 100 is arranged on the deck 4 allowing to feed and remove drilling tubulars to and from the firing line 25 when the tower is in the first operative position thereof associated with the moonpool area 5.

(35) Tubulars storage racks or other storage devices 130 are arranged adjacent the catwalk machine 100.

(36) The hatch 90 associated with the second moonpool opening 6a is provided with a pair of skid rails 91, 92 thereon. The deck 4, in a region adjacent the moonpool opening 6a, is provided with a pair of deck mounted skid rails 95, 96. In the closed position of hatch 90, see FIG. 3, the pair of skid rails 91, 92 provided thereon align with the pair of deck mounted skid rails 95, 96 in order to allow skidding of an object onto and off the one or more closed position hatches. For example, the object is coiled tubing injector device 110.

(37) The vessel has, here aft of the moonpool 6, on the deck 4 a pair of skid rails 97, 98 on which a skiddable coiled tubing reel 115 is placed.

(38) Not depicted here is an embodiment wherein the vessel is provided with a storage reel storing or configured to store thereon a coiled tubing guide hose, e.g. a composite coiled tubing guide hose. The vessel 1 may be provided with a coiled tubing guide hose tensioner device 120 having multiple tracks 121, 122 in a substantially vertical arrangement. As will be appreciated the tensioner device 120 is configured to be arranged in an operative position thereof above second moonpool area 6 and to support the length of coiled tubing guide hose extending into the sea to subsea equipment mounted on a subsea well head.