Dual activity off-shore drilling rig

Patent metadata

Field	Value
Publication number	US-9834998-B2
Application number	US-201414891808-A
Country	US
Kind code	B2
Filing date	May 20, 2014
Priority date	May 20, 2013
Publication date	Dec 5, 2017
Grant date	Dec 5, 2017

Abstract

An offshore drilling rig configured for lowering and/or raising a string of tubular equipment into a subsea borehole. The drilling rig includes a drill deck; a first hoisting system being adapted for raising or lowering a first load carrier along a vertical first hoisting axis, wherein the first hoisting system is supported by a first support structure extending upwardly relative to the drill deck; a second hoisting system being adapted for raising or lowering a second load carrier along a vertical second hoisting axis located apart from the first hoisting axis, wherein the second hoisting system is supported by a second support structure extending upwardly relative to the drill deck; and a joint operations well center on the drill deck. During joint operations, the first and second hoisting axes are preferably located apart from the joint operations well center.

First claim

The invention claimed is:

1. An offshore drilling rig configured for lowering and/or raising a string of tubular equipment into a subsea borehole, the drilling rig comprising:
a drill deck;
a first hoisting system being adapted for raising or lowering a first load carrier along a vertical first hoisting axis, wherein the first hoisting system is supported by a first support structure extending upwardly relative to the drill deck and adapted for individual operation at a first work centre in the drill deck at said first hoisting axis;
a second hoisting system being adapted for raising or lowering a second load carrier along a vertical second hoisting axis spaced apart from the first hoisting axis, wherein the second hoisting system is supported by a second support structure, that is separate from or common with said first support structure, extending upwardly relative to the drill deck and adapted for individual operation at a second work centre in the drill deck at said second hoisting axis;
a joint operations well centre on the drill deck, wherein the first and second hoisting systems are configured for operating in conjunction over the joint operations well centre, wherein the first and second hoisting axes during joint operations are located apart from the joint operations well center and the positions of the first and second hoisting axes are fixed with respect to the drill deck.

2. An offshore drilling rig according to claim 1 , wherein the joint operations well centre is the first well centre or the second well centre.

3. An offshore drilling rig according to claim 1 , wherein the joint operations well centre is a third well centre different from the first and second well centres.

4. An offshore drilling rig according to claim 3 , wherein the positions of the first, second and third well centres are fixed with respect to the drill deck.

5. An offshore drilling rig according claim 1 , wherein at least one well centre is movable with respect to the drill deck.

6. An offshore drilling rig according to claim 5 , wherein the movable well centre is the joint operations well centre.

7. An offshore drilling rig according to claim 1 wherein the first and second hoisting systems are arranged in a side-by-side configuration.

8. An offshore drilling rig according to claim 1 , further comprising a connecting tool comprising a load bearing device adapted for suspending tubular equipment in axial alignment with a vertical tool axis of the connecting tool, wherein the first and second hoisting axes during joint operations are coupled together by means of the connection tool such that the tool axis is located spaced apart from the first and second hoisting axes and in alignment with the joint operations well centre.

9. An offshore drilling rig according to claim 8 , wherein the tool axis is located between the first and second hoisting axes.

10. An offshore drilling rig according to claim 8 , wherein the connecting tool has coupling points at which it is coupled to the hoisting systems, wherein first coupling points of the connecting tool are coupled to first elements of the drilling rig that are vertically moveable with respect to the drill deck by means of and/or in conjunction with the first hoisting system, wherein said vertically moveable first elements comprise one or more of a first load carrier of the first hoisting system, a first dolly that is vertically moveable attached to the first support structure, and a first top drive suspended by the first hoisting system and attached to the first support structure via the first dolly.

11. An offshore drilling rig according to claim 8 , wherein second coupling points of the connecting tool are coupled to second elements of the drilling rig that are vertically moveable with respect to the drill deck by means of and/or in conjunction with the second hoisting system, wherein said vertically moveable second elements comprise one or more of a second load carrier of the second hoisting system, a second dolly that is vertically moveable attached to the second support structure, and a second top drive suspended by the second hoisting system and attached to the second support structure via the second dolly.

12. An offshore drilling rig according to claim 8 , wherein the connecting tool further comprises a tubular mud handling device configured for at least filling drilling mud to the inside of the tubular equipment through a sealing attachment, wherein a principal direction of the sealing attachment is arranged in axial alignment with the tool axis.

13. An offshore drilling rig according to claim 12 , wherein the sealing attachment is an axial press-fit seal applied in the direction of the tool axis.

14. An offshore drilling rig according to claim 12 , wherein the tubular mud handling device is attached to the connecting tool.

15. An offshore drilling rig according to claim 14 , wherein the tubular mud handling device is attached to the connecting tool by means of a gimbal mount.

16. An offshore drilling rig according to claim 15 , further comprising at least one top drive suspended from one of the load carriers.

17. An offshore drilling rig according to claim 16 , wherein a mud handling system of the top drive is operatively coupled to the tubular mud handling device via a flexing/flexible fluid connection.

18. An offshore drilling rig according to claim 8 , wherein the connecting tool further comprises a swivel device (or is adapted to receive a swivel device) so the connecting tool allows for rotation around a vertical swivel axis of a load suspended in the load bearing device.

19. An offshore drilling rig according to claim 18 , wherein the connecting tool and/or the swivel device comprises a rotary actuator for driving the rotation about the swivel axis.

20. An offshore drilling rig according to item 19 , wherein the rotary actuator comprises an electrical or hydraulic motor.

21. An offshore drilling rig according to claim 18 , further comprising at least one top drive suspended from one of the load carriers wherein the top drive is operatively coupled to the swivel device so as to drive the swivel rotation and/or wherein the top drive is operatively coupled to the link tilt device so as to drive the link tilt action.

22. An offshore drilling rig according to claim 8 , wherein the connecting tool further comprises a link tilt device adapted for tilting the load bearing device at least about a horizontal tilt axis.

23. A method of lowering and/or raising a string of tubular equipment into a subsea borehole through a joint operations well centre in a drill deck of an offshore drilling rig according claim 1 , the method comprising
providing a first hoisting system for raising or lowering a first load carrier along a vertical first hoisting axis, wherein the first hoisting system is supported by a first support structure and adapted for individual operation at a first work centre in the drill deck at said first hoisting axis;
providing a second hoisting system for raising or lowering a second load carrier along a vertical second hoisting axis, wherein the second hoisting system is supported by a second support structure, that is separate from or common with said first support structure, and adapted for individual operation at a second work centre in the drill deck at said second hoisting axis;
wherein the first and second hoisting axes are laterally displaced from another by a hoisting axis distance and fixed relative to the drill dec

Assignees

• Maersk Drilling As

Inventors

• Holck Jesper

Classifications

• E21B15/02 Primary

  specially adapted for underwater drilling (E21B15/04 takes precedence) · CPC title

• E21B19/084

  with flexible drawing means, e.g. cables · CPC title

• E21B19/002

  specially adapted for underwater drilling (E21B19/09, E21B19/143 take precedence) · CPC title

• E21B19/02

  Rod or cable suspensions · CPC title

• E21B19/008 Primary

  Winding units, specially adapted for drilling operations · CPC title