OPEN CANTILEVER TENSION SYSTEM

Abstract

A drilling system includes a hull, an open cantilever mounted on the hull, a blowout preventer stack supported by the open cantilever, a plurality of beams installed horizontally and supported on the open cantilever, and a conductor tension unit cage including a conductor tension unit. The conductor tension unit cage is installed below the blowout preventer stack, and is supported by the plurality of beams. The conductor tension unit is configured to apply tension to a conductor pipe extending through the blowout preventer stack when the open cantilever is skidded out from the hull.

Description

BACKGROUND

A jack-up rig is a floating drilling unit that includes a jacking mechanism attached to a floating barge with a rig floor. The jack-up rig is fitted with long support legs that can be raised or lowered to a desired height. As such, the floating barge may be raised to a desired height above the water so that any wave, tidal, and current loading acts only on the support legs instead of on the barge.

The jack-up rig may be provided with an open cantilever having a cantilever platform, and at least one drilling assembly may be provided on the cantilever platform. There is a need to increase the operational envelope of open cantilever jack-up rigs and to reduce the installed weight of such drilling systems, thereby lowering the overall cost of the jack-up rig.

SUMMARY

According to one or more embodiments of the present disclosure, a drilling system includes a hull, an open cantilever mounted on the hull, wherein the open cantilever is configured to skid out from the hull, a blowout preventer stack supported by the open cantilever, a plurality of beams installed horizontally and supported on the open cantilever, and a conductor tension unit cage including a conductor tension unit. According to one or more embodiments of the present disclosure, the conductor tension unit cage is installed below the blowout preventer stack, and is supported by the plurality of beams. According to one or more embodiments of the present disclosure, the conductor tension unit is configured to apply tension to a conductor pipe extending through the blowout preventer stack when the open cantilever is skidded out from the hull.

According to one or more embodiments of the present disclosure, a drilling system includes a full, an open cantilever mounted on the hull, wherein the open cantilever is configured to skid out from the hull via a plurality of cantilever skidding beams, a blowout preventer stack supported by the open cantilever, and a conductor tension unit cage including a conductor tension unit, wherein the conductor tension unit cage is removably attached to the plurality of cantilever skidding beams.

According to one or more embodiments of the present disclosure, a system includes an open cantilever, a blowout preventer stack supported by the open cantilever, wherein the open cantilever defines a well center through which well center drilling operations may be performed through the blowout preventer stack, a plurality of beams installed horizontally with respect to an opening of the open cantilever, wherein the plurality of beams is supported on the open cantilever, and a conductor tension unit cage including a conductor tension unit, wherein the conductor tension unit cage is installed below the blowout preventer stack, and is supported by the plurality of beams, and wherein the conductor tension unit is configured to apply tension to a conductor pipe extending through the blowout preventer stack at a position away from the well center.

However, many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Certain embodiments of the disclosure will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements. It should be understood, however, that the accompanying figures illustrate the various implementations described herein and are not meant to limit the scope of various technologies described herein, and:

FIG. 1 shows a traditional open cantilever system;

FIG. 2 shows a BOP that may be used in an open cantilever system;

FIG. 3 shows an open cantilever tension system according to one or more embodiments of the present disclosure; and

FIG. 4 shows an alternative configuration of an open cantilever tension system according to one or more embodiments of the present disclosure.

DETAILED DESCRIPTION

In the following description, numerous details are set forth to provide an understanding of some embodiments of the present disclosure. However, it will be understood by those of ordinary skill in the art that the system and/or methodology may be practiced without these details and that numerous variations or modifications from the described embodiments may be possible.

In the specification and appended claims, the terms “connect,” “connection,” “connected,” “in connection with,” and “connecting,” are used to mean “in direct connection with,” in connection with via one or more elements.” The terms “couple,” “coupled,” “coupled with,” “coupled together,” and “coupling” are used to mean “directly coupled together,” or “coupled together via one or more elements.” The term “set” is used to mean setting “one element” or “more than one element.” As used herein, the terms “up” and “down,” “upper” and “lower,” “upwardly” and “downwardly,” “upstream” and “downstream,” “uphole” and “downhole,” “above” and “below,” “top” and “bottom,” and other like terms indicating relative positions above or below a given point or element are used in this description to more clearly describe some embodiments of the disclosure. Commonly, these terms relate to a reference point at the surface from which drilling operations are initiated as being the top point and the total depth being the lowest point, wherein the well (e.g., wellbore, borehole) is vertical, horizontal, or slanted relative to the surface.

The present disclosure generally relates to a drilling rig. More specifically, the present disclosure relates to a jack-up rig provided with an open cantilever having an associated open cantilever tension system that facilitates drilling operations. Advantageously, the open cantilever tension system increases the operational envelope for the open cantilever of the jack-up rig. Further, the open cantilever tension system according to one or more embodiments of the present disclosure allows the associated open cantilever to exhibit a reduced installed weight when compared to traditional open cantilevers and closed cantilevers. In this way, the open cantilever system according to one or more embodiments of the present disclosure advantageously combines a light cantilever design with an operational functionality equal to or better than heavier designs.

Referring now to FIG. 1, a traditional open cantilever system 10 is shown. As shown in FIG. 1, the traditional open cantilever system 10 is part of a larger drilling system 12 including a hull 14. The traditional open cantilever system 10 includes an open cantilever 16 mounted on the hull 14. The open cantilever 16 defines a well center through which well center drilling operations may be performed through a blowout preventer stack 18 supported by the open cantilever 16. As further shown in FIG. 1, a Texas deck 20 (i.e., a foldable deck) is mounted on the hull 14, and the Texas deck 20 supports a conductor tension unit 22. In this way, the Texas deck 20 and the conductor tension unit 22 are aligned with the well center of the open cantilever 16 to support drilling operations. Because the conductor tension unit 22 is aligned with well center of the open cantilever 16, the conductor tension unit 22 is positioned to apply tension below the blowout preventer stack 18 to a conductor pipe 24 extending through the blowout preventer stack 18. An example of a conductor pipe 24 extending through a blowout preventer stack 18 is shown in FIG. 2, for example. Indeed, in the traditional open cantilever system 10, the ability to apply tension to the conductor pipe 24 below the blowout preventer stack 18 is limited to when the open cantilever 16 is positioned with the well center above the Texas deck 20. Unfortunately, however, if the open cantilever 16 is skidded further out from the hull 14 (i.e., away from the well center), the conductor tension unit 22 cannot be utilized to apply the requisite tension to the conductor pipe 24 extending through the blowout preventer stack 18 to support drilling operations. Other wire tension solutions have been used, but these can be expensive and difficult to handle during drilling operations.

Referring now to FIG. 3, an open cantilever tension system 25 is shown according to one or more embodiments of the present disclosure. As specifically shown in FIG. 3, the open cantilever tension system 25 includes an open cantilever 16, and the open cantilever tension system 25 is part of a drilling system 32 that includes a hull 14. According to one or more embodiments of the present disclosure, the open cantilever 16 is mounted on the hull 14, and is configured to skid out from the hull 14 to facilitate drilling operations. As shown in FIG. 3, the drilling system 32 also includes a blowout preventer stack 18 supported by the open cantilever 16. As shown in FIG. 3, the open cantilever tension system 25 according to one or more embodiments of the present disclosure also includes a plurality of beams 28 installed horizontally with respect to an opening 17 of the open cantilever 16. According to one or more embodiments of the present disclosure, the plurality of beams 28 is supported on the open cantilever 16 via a plurality of wires supported at a top of a drilling rig of the drilling system 32 (not shown). By supporting the plurality of beams 28 via the plurality of wires in this way, the plurality of beams 28 is able to maintain a slim configuration for easier handling and reduced weight.

Still referring to FIG. 3, the open cantilever tension system 25 according to one or more embodiments of the present disclosure includes a conductor tension unit cage 26 that houses a conductor tension unit 22. According to one or more embodiments of the present disclosure, the conductor tension unit cage 26 is installed below the blowout preventer stack 18. As further shown in FIG. 3, the conductor tension unit cage 26 is supported by the plurality of beams 28. According to one or more embodiments of the present disclosure, the conductor tension unit cage 26 is hung from the plurality of beams 28, as shown in FIG. 3, for example. However, the conductor tension unit cage 26 may also be stored on top of the plurality of beams 28 without departing from the scope of the present disclosure. As also shown in FIG. 3, the Texas deck 20 is mounted on the hull 14 of the drilling system 32. However, as shown in FIG. 3, the conductor tension unit 22 is not mounted on the Texas deck 20, according to one or more embodiments of the present disclosure.

Still referring to FIG. 3, the drilling system 32 according to one or more embodiments of the present disclosure may also include at least one platform 30 supported by the plurality of beams 28. According to one or more embodiments of the present disclosure, the at least one platform 30 is configured to support the blowout preventer stack 18, which is normally hinged on the starboard and port side of the open cantilever 16. According to one or more embodiments of the present disclosure, the plurality of beams 28 is installed forward and aft of the at least one platform 30, for example. Because the plurality of beams 28 supports the at least one platform 30, the at least one platform 30 can now be simplified and lighter, as the at least one platform 30 can be placed along all positions on the plurality of beams 28, according to one or more embodiments of the present disclosure. According to one or more embodiments of the present disclosure, the plurality of beams 28 is also able to directly support the blowout preventer stack 18 without the at least one platform 30, for example.

Referring now to FIG. 4, an alternative configuration of an open cantilever tension system 25 according to one or more embodiments of the present disclosure is shown. Specifically, as shown in FIG. 4, the open cantilever 16 of the open cantilever tension system 25 is skidded out from the hull 14. Because the conductor tension unit cage 26 that houses the conductor tension unit 22 is installed below the blowout preventer stack 18, and is supported by the plurality of beams 28, the conductor tension unit 22 according to one or more embodiments of the present disclosure is positioned and able to apply tension to a conductor pipe 24 extending through the blowout preventer stack 18, even when the open cantilever 16 is skidded out from the hull 14. That is, in the open cantilever tension system 25 according to one or more embodiments of the present disclosure, the conductor tension unit 22 is able to apply tension to the conductor pipe 24 extending through the blowout preventer stack 18 at a position away from the well center, for example.

As an alternative embodiment, the open cantilever tension system 25 may be hooked up to the skidding beams of the open cantilever 16, for example. In this alternative configuration, the conductor tension unit 22 would still be positioned and able to apply tension to the conductor pipe 24 extending through the blowout preventer stack 18, even when the open cantilever 16 is skidded out from the hull 14, according to one or more embodiments of the present disclosure. Stated another way, in this alternative configuration of the open cantilever tension system 25, the conductor tension unit 22 would still be positioned and able to apply tension to the conductor pipe 24 extending through the blowout preventer stack 18 at a position away from the well center, for example. In this alternative configuration, the conductor tension unit cage 26 that houses the conductor tension unit 22 can be removed from the open cantilever tension system 25 if not required for the drilling operation.

As a result of the configuration of the open cantilever tension system 25 according to one or more embodiments of the present disclosure, the open cantilever tension system 25 is able to minimize the operational advantage that a closed cantilever system has over traditional open cantilever systems, such as that described in FIG. 1, for example. Indeed, because the open cantilever 16 of the open cantilever tension system 25 is able to skid out and in with respect to the hull 14, and is also able to move side to side, the open cantilever tension system 25 according to one or more embodiments of the present disclosure increases the operational envelope for an open cantilever jack-up rig. Moreover, because the plurality of beams 28 of the open cantilever tension system 25 can support the conductor tension unit cage 26 housing the conductor tension unit 22, and because the plurality of beams 28 can support the at least one platform 30 for supporting the blowout preventer stack 18, the installed weight on the open cantilever 16 may be reduced, thereby lowering the overall cost of the rig, improving health, safety, and environment (HSE) conditions for the blowout preventer stack 18 operations, and minimizing material handling. Moreover, lowering the installed weight on the open cantilever 16 improves the overall capacity of the rig, providing more capacity for applying tension and pulling loads, for example. In this way, the open cantilever tension system 25 according to one or more embodiments of the present disclosure combines a light cantilever design with the operational functionality equal to or better than heavier designs.

Although a few embodiments of the disclosure have been described in detail above, those of ordinary skill in the art will readily appreciate that many modifications are possible without materially departing from the teachings of this disclosure. Accordingly, such modifications are intended to be included within the scope of this disclosure as defined in the claims.

Claims

1. A drilling system, comprising: a hull;an open cantilever mounted on the hull, wherein the open cantilever is configured to skid out from the hull;a blowout preventer stack supported by the open cantilever;a plurality of beams installed horizontally and supported on the open cantilever; anda conductor tension unit cage comprising a conductor tension unit,wherein the conductor tension unit cage is installed below the blowout preventer stack, and is supported by the plurality of beams, andwherein the conductor tension unit is configured to apply tension to a conductor pipe extending through the blowout preventer stack when the open cantilever is skidded out from the hull.

2. The drilling system of claim 1, further comprising: at least one platform supported by the plurality of beams, wherein the at least one platform is configured to support the blowout preventer stack.

3. The drilling system of claim 1, wherein the plurality of beams is supported on the open cantilever via a plurality of wires supported at a top of a drilling rig of the drilling system.

4. The drilling system of claim 1, wherein the conductor tension unit cage is hung from the plurality of beams.

5. The drilling system of claim 1, wherein the conductor tension unit cage is stored on top of the plurality of beams.

6. The drilling system of claim 1, wherein the open cantilever defines a well center through which well center drilling operations may be performed through the blowout preventer stack.

7. The drilling system of claim 1, further comprising: a Texas deck mounted on the hull, wherein the conductor tension unit is not mounted on the Texas deck.

8. A drilling system, comprising: a hull;an open cantilever mounted on the hull, wherein the open cantilever is configured to skid out from the hull via a plurality of cantilever skidding beams;a blowout preventer stack supported by the open cantilever; anda conductor tension unit cage comprising a conductor tension unit,wherein the conductor tension unit cage is removably attached to the plurality of cantilever skidding beams.

9. The drilling system of claim 8, further comprising: a Texas deck mounted on the hull, wherein the conductor tension unit is not mounted on the Texas deck.

10. A system, comprising: an open cantilever;a blowout preventer stack supported by the open cantilever,wherein the open cantilever defines a well center through which well center drilling operations may be performed through the blowout preventer stack;a plurality of beams installed horizontally with respect to an opening of the open cantilever, wherein the plurality of beams is supported on the open cantilever; anda conductor tension unit cage comprising a conductor tension unit,wherein the conductor tension unit cage is installed below the blowout preventer stack, and is supported by the plurality of beams, andwherein the conductor tension unit is configured to apply tension to a conductor pipe extending through the blowout preventer stack at a position away from the well center.

11. The system of claim 10, further comprising: at least one platform supported by the plurality of beams, wherein the at least one platform is configured to support the blowout preventer stack.

12. The system of claim 10, wherein the plurality of beams is supported on the open cantilever via a plurality of wires supported at a top of a drilling rig.

13. The system of claim 10, wherein the conductor tension unit cage is hung from the plurality of beams.

14. The system of claim 10, wherein the conductor tension unit cage is stored on top of the plurality of beams.

15. The system of claim 10, further comprising: a Texas deck mounted on the hull, wherein the conductor tension unit is not mounted on the Texas deck.