Vertically folding service arm for a movable platform offshore drilling or servicing rig

• US 20060078406A1
• Filed: 10/11/2005
• Published: 04/13/2006
• Est. Priority Date: 10/12/2004
• Status: Active Grant

• Current Assignee: National Oilwell LP (National Oilwell Varco Incorporated)
• Original Assignee: National Oilwell LP (National Oilwell Varco Incorporated)
• Inventors: Donnally, Robert B., Fehres, Neil E.
• Granted Patent: US 7,234,896 B2
• Time in Patent Office: Days
• US Class Current: 414/22.620
• CPC Class Codes: E21B 19/084 with flexible drawing means, e.g. cables

Abstract

An apparatus and method for maintaining electrical and hydraulic connections between a junction box (or junction boxes) located on or near an offshore platform'"'"'s floor and a movable drilling rig structure are disclosed. The disclosed invention is a unique vertically folding service arm capable of moving in both the horizontal and vertical directions in order to provide enhanced range of movement. The increased range of movement provided by the vertically folding service arm of the present invention allows electrical and hydraulic supply lines to remain connected between a junction box (or boxes) located on or near the platform floor and the rig structure even as the rig structure moves back-and-forth on the platform between multiple well centers. The vertically folding service arm of the present invention can also be easily disconnected and “folded” for transport without requiring the electrical and hydraulic supply lines to be disconnected from the drilling rig structure.

Claims

1. An apparatus for maintaining a connection to a movable rig structure on a platform comprising:

a support post having a first end and a second end;

a first arm having a first end and a second end, wherein the first end is operatively connected to the second end of the support post such that the first arm is adapted for movement in a vertical plane;

a second arm having a first end and a second end, wherein the first end of the second arm is operatively connected to the second end of the first arm and the second end of the second arm is operatively connected to the movable rig structure, the second arm being adapted for movement in a vertical plane and in a horizontal plane;

a winch connected to the second arm;

a wireline extending from the winch to the second end of the support post; and

at least one supply line wherein the at least one supply line is supported by the first arm and the second arm such that the at least one supply line extends from the support post to the movable rig structure.

2. The apparatus of claim 1 wherein a connector operatively connects the second end of the second arm to the movable rig structure, the connector comprising one or more vertical pins adapted to allow the connector to move in a horizontal plane.

3. The apparatus of claim 1 wherein the winch and wireline are adapted to reduce the forces acting on the support post that are created by the movement of the first arm and the second arm in the vertical plane.

4. The apparatus of claim 3 wherein the second end of the first arm is operatively connected to the first end of the second arm by a hinge.

5. The apparatus of claim 4 wherein opening of the hinge extends the second arm away from the first arm.

6. The apparatus of claim 1 wherein the first end of the first arm is operatively connected to the second end of the support post by a universal joint that is adapted for movement of the first arm in both a horizontal plane and a vertical plane.

7. The apparatus of claim 1 wherein the support post is connected to the platform and is adapted to rotate.

8. The apparatus of claim 7 wherein the first end of the first arm is operatively connected to the second end of the support post by a pivoting joint.

9. The apparatus of claim 1 further comprising at least one junction box, wherein a first end of the at least one supply line is connected to the at least one junction box.

10. The apparatus of claim 9 further comprising a conduit connected to the at least one junction box, the conduit connecting electrical and hydraulic supply lines to the junction box.

11. The apparatus of claim 2 wherein the connector is operatively connected to the second end of the second arm by a pivoting joint adapted to allow the second arm to rotate in a vertical plane.

12. The apparatus of claim 11 wherein the first arm is adapted to be detached from and reattached to the support post.

13. The apparatus of claim 12 wherein the first arm further comprises a lifting lug.

14. The apparatus of claim 13 wherein the apparatus is adapted for storage on the movable rig structure by closing the hinge between the first arm and the second arm and rotating the apparatus about the pivoting joint between the second arm and the connector.

15. The apparatus of claim 1 wherein the first arm and the second arm each comprise two sides and one or more cable trays extending between the two sides of each arm.

16. The apparatus of claim 15 wherein the one or more cable trays of each arm support the at least one supply line.

17. The apparatus of claim 1 wherein the first arm and the second arm each comprise two sides and a plurality of rungs extending between the two sides of each arm.

18. The apparatus of claim 17 wherein the plurality of rungs support the at least one supply line.

19. The apparatus of claim 1 further comprising multiple supply lines having first and second ends, wherein the supply lines pass through the length of the first arm and through the length of the second arm, and wherein the second ends of the multiple supply lines are connected to the movable rig structure.

20. A vertically folding service arm for use on a drilling platform, the service arm comprising:

a support post connected to the drilling platform, wherein the support post is adapted to rotate;

a first portion of the service arm operatively connected to the support post such that the first portion of the service arm is adapted for movement in a vertical plane and such that the service arm may be detached from the support post and lifted onto the movable rig to be stored;

a second portion of the service arm, wherein the second portion of the service arm is operatively connected to the first portion of the service arm such that the service arm can extend away from the support post;

a winch mounted on the second portion of the service arm and a wireline extending from the winch to the support post, wherein the winch and wireline are adapted to reduce the forces acting on the support post that are created by extension of the service arm away from the support post;

a connector operatively connecting the second portion of the service arm to a rig that is movable on the drilling platform such that the second portion of the service arm is adapted for movement in both a vertical plane and a horizontal plane.

21. The service arm of claim 20 wherein the first portion and the second portion of the service arm each comprise two sides and one or more cable trays extending between the two sides of each portion of the service arm.

22. The apparatus of claim 20 wherein the first portion and the second portion of the service arm each comprise two sides and a plurality of rungs extending between the two sides of each potion of the service arm.

23. The service arm of claim 20 further comprising a lug attached to the service arm.

24. The service arm of claim 23 wherein a wireline from a crane is connected to the lug to lift the service arm onto the rig.

25. The service arm of claim 20 further comprising at least two support beams connected to the rig.

26. The service arm of claim 25 wherein the connector is operatively connected to the at least two support beams such that the connector is adapted for movement in a horizontal plane.

27. The service arm of claim 26 wherein the connector is operatively connected to the at least two support beams by one or more vertical pins.

28. A method of connecting a supply line to a moveable rig on a platform comprising:

operatively connecting a first arm to a support post such that the first arm is adapted for movement in a vertical plane;

operatively connecting a first end of a second arm to the first arm and operatively connecting a connector to a second end of the second arm such that the second arm is adapted for movement in the vertical plane;

operatively connecting the connector to the moveable rig such that the second arm is adapted for movement in a horizontal plane; and

operatively connecting a supply line to the mobile rig such that the supply line extends from the platform and is supported by the first arm and the second arm.

29. The method of claim 28 further comprising operatively connecting a winch and wireline to the second arm such that the wireline extends from the winch to the support post.

30. The method of claim 29 wherein the support post is connected to the platform and is adapted to rotate.

31. The method of claim 29 wherein the first arm is operatively connected to the support post by a universal joint that is adapted to allow the first arm to move in both a horizontal plane and a vertical plane.

32. The method of claim 30 wherein the first arm is operatively connected to the second arm by a hinge.

33. The method of claim 32 further comprising the step of opening the hinge to extend the second arm away from the first arm.

34. A method of storing a service arm on a moveable rig of a platform comprising:

detaching one or more supply lines from a junction box, the one or more supply lines extending from the junction box to the movable rig and supported by a first portion of the service arm and a second portion of the service arm;

bringing together the first portion of the service arm and the second portion of the service arm by closing a hinge connecting the first portion to the second portion;

detaching the first portion of the service arm from a support post connected to the platform;

vertically rotating the service arm about a pin, wherein the pin operatively connects the second portion of the service arm to a connector that is attached to the moveable rig; and

storing the service arm on the moveable rig.

35. The method of claim 34 wherein the first portion of the service arm further comprises a lug.

36. The method of claim 35 further comprising the step of lifting the service arm with a crane having a wireline connected to the lug.

37. The method of claim 36 wherein the one or more supply lines are connected to the moveable rig while the service arm is stored on the moveable rig.