U.S. patent application number 14/592025 was filed with the patent office on 2015-07-16 for underwater drilling rig assembly and method of operating the underwater drilling rig assembly.
The applicant listed for this patent is CONOCOPHILLIPS COMPANY. Invention is credited to Peter George NOBLE, Randall Scott SHAFER.
Application Number | 20150197989 14/592025 |
Document ID | / |
Family ID | 53520905 |
Filed Date | 2015-07-16 |
United States Patent
Application |
20150197989 |
Kind Code |
A1 |
SHAFER; Randall Scott ; et
al. |
July 16, 2015 |
UNDERWATER DRILLING RIG ASSEMBLY AND METHOD OF OPERATING THE
UNDERWATER DRILLING RIG ASSEMBLY
Abstract
An underwater drilling rig assembly includes a hull anchored to
a sea floor with at least one anchoring component. Also included is
a rig assembly disposed on the hull. Further included is a mast
unit of the rig assembly. Yet further included is a pipe handling
unit configured to maneuver a drill pipe into operative
communication with the mast unit. Also included is a drill bit
assembly operatively coupled to the mast unit. Further included is
a control unit positioned proximate the sea floor and in operative
communication with a plurality of components of the underwater
drilling rig assembly, the control unit operatively coupled to at
least one surface vessel for remote control of the underwater
drilling rig assembly.
Inventors: |
SHAFER; Randall Scott;
(Houston, TX) ; NOBLE; Peter George; (Spring,
TX) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
CONOCOPHILLIPS COMPANY |
Houston |
TX |
US |
|
|
Family ID: |
53520905 |
Appl. No.: |
14/592025 |
Filed: |
January 8, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61928213 |
Jan 16, 2014 |
|
|
|
Current U.S.
Class: |
175/6 |
Current CPC
Class: |
E21B 7/124 20130101 |
International
Class: |
E21B 7/124 20060101
E21B007/124; E21B 33/038 20060101 E21B033/038; E21B 44/00 20060101
E21B044/00; E21B 17/00 20060101 E21B017/00; E21B 43/10 20060101
E21B043/10; E21B 41/08 20060101 E21B041/08; E21B 17/01 20060101
E21B017/01 |
Claims
1. A method of operating an underwater drilling rig assembly
comprising: lowering a hull with a rig assembly disposed thereon to
a water depth proximate the sea floor; leveling the hull with a
plurality of legs extending from the hull and supported by the sea
floor; and operatively coupling a control unit of the rig assembly
to a surface vessel, the control unit in operative communication
with a plurality of components of the underwater drilling rig
assembly, the control unit configured to facilitate remote control
of the underwater drilling rig assembly with the surface
vessel.
2. The method of claim 1, further comprising anchoring the hull to
the sea floor with a plurality of spud cans operatively coupled to
an end of the plurality of legs.
3. The method of claim 1, further comprising ballasting the hull at
a depth proximate the sea floor.
4. The method of claim 1, further comprising observing installation
of the underwater drilling rig assembly with an underwater remote
operated vehicle (ROV).
5. The method of claim 1, further comprising pumping fluid to a
water surface with a pump of the control unit.
6. The method of claim 1, further comprising providing power and
fluid to the underwater drilling rig assembly through at least one
line connected to the surface vessel and the control unit.
7. The method of claim 1, further comprising installing a blowout
preventer (BOP) proximate a wellhead.
8. The method of claim 1, further comprising drilling a hole in the
sea floor with a drill bit assembly of the rig assembly.
9. The method of claim 8, further comprising installing a casing
within the hole drilled with the drill bit assembly.
10. An underwater drilling rig assembly comprising: a hull anchored
to a sea floor with at least one anchoring component; a rig
assembly disposed on the hull; a mast unit of the rig assembly; a
pipe handling unit configured to maneuver a drill pipe into
operative communication with the mast unit; a drill bit assembly
operatively coupled to the mast unit; and a control unit positioned
proximate the sea floor and in operative communication with a
plurality of components of the underwater drilling rig assembly,
the control unit operatively coupled to at least one surface vessel
for remote control of the underwater drilling rig assembly.
11. The underwater drilling rig assembly of claim 10, wherein the
hull is configured to be ballasted proximate the sea floor.
12. The underwater drilling rig assembly of claim 11, wherein the
hull comprises a plurality of legs extending therefrom, each of the
legs configured to engage the sea floor to support the load of the
underwater drilling rig assembly.
13. The underwater drilling rig assembly of claim 10, wherein the
at least one anchoring component comprises a plurality of spud cans
configured to be at least partially embedded within the sea
floor.
14. The underwater drilling rig assembly of claim 10, wherein the
control unit is operatively coupled to the at least one surface
vessel with at least one line.
15. The underwater drilling rig assembly of claim 14, wherein the
at least one line is a flow line configured to route fluid between
the at least one surface vessel and the underwater drilling rig
assembly.
16. The underwater drilling rig assembly of claim 14, wherein the
at least one line comprises an electrical cable for providing power
to the plurality of components of the underwater drilling rig
assembly.
17. The underwater drilling rig assembly of claim 10, wherein the
underwater drilling rig assembly is configured to operate in an
automated drilling mode.
18. The underwater drilling rig assembly of claim 10, wherein the
underwater drilling rig assembly is an unmanned assembly.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a non-provisional application which
claims benefit under 35 USC .sctn.119(e) to U.S. Provisional
Application Ser. No. 61/928,213 filed Jan. 16, 2014, entitled
"UNDERWATER DRILLING RIG ASSEMBLY AND METHOD OF OPERATING THE
UNDERWATER DRILLING RIG ASSEMBLY," which is incorporated herein in
its entirety.
FIELD OF THE INVENTION
[0002] This invention relates generally to offshore or underwater
drilling systems and, more particularly, to an underwater drilling
rig assembly, as well as a method of installing and operating the
underwater drilling rig assembly.
BACKGROUND OF THE INVENTION
[0003] Drilling for hydrocarbons (e.g., oil and gas) offshore poses
a number of challenges that are not a consideration during onshore
drilling operations. Typically, floating or fixed platforms that
are equipped with drilling equipment are employed to facilitate the
offshore drilling operation. A riser connection between the
platform and the sea floor is used to circulate a drilling fluid
(e.g., drilling mud) during drilling. Such a structure becomes more
challenging to maintain during deepwater operations. Furthermore,
structural features must be included on the platform to accommodate
the wave motion of the platform relative to the sea floor. Often,
the drilling operations must be interrupted during extreme weather
conditions, which involve hazardous operations and high costs.
[0004] Severe weather environments and deepwater sites require
large drilling vessels with substantial marine support. For
example, in the Arctic ice forces can be high and conventional
drilling vessels cannot resist ice forces and therefore cannot
drill in areas with heavy ice or require a high level of ice
management support that is often not feasible. Large vessels for
severe environment operations require a high level of personnel to
support the operations.
[0005] In view of the foregoing challenges, efforts have been made
to overcome the challenges by using a seabed rig that is partially
or fully submerged. The prior efforts use large structures that are
typically supported by the well and often require a surface vessel
to be positioned directly over the seabed rig. Maintaining precise
position over the seabed rig with the surface vessel includes
several challenges due to harsh environment conditions described
above and does not fully overcome the disadvantages associated with
drilling platforms in such environments.
SUMMARY OF THE INVENTION
[0006] In one embodiment, a method of operating an underwater
drilling rig assembly is provided. The method includes lowering a
hull with a rig assembly disposed thereon to a water depth
proximate the sea floor. The method also includes leveling the hull
with a plurality of legs extending from the hull and supported by
the sea floor. The method further includes operatively coupling a
control unit of the rig assembly to a surface vessel, the control
unit in operative communication with a plurality of components of
the underwater drilling rig assembly, the control unit configured
to facilitate remote control of the underwater drilling rig
assembly with the surface vessel.
[0007] In another embodiment, an underwater drilling rig assembly
includes a hull anchored to a sea floor with at least one anchoring
component. Also included is a rig assembly disposed on the hull.
Further included is a mast unit of the rig assembly. Yet further
included is a pipe handling unit configured to maneuver a drill
pipe into operative communication with the mast unit. Also included
is a drill bit assembly operatively coupled to the mast unit.
Further included is a control unit positioned proximate the sea
floor and in operative communication with a plurality of components
of the underwater drilling rig assembly, the control unit
operatively coupled to at least one surface vessel for remote
control of the underwater drilling rig assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The invention, together with further advantages thereof, may
best be understood by reference to the following description taken
in conjunction with the accompanying figures by way of example and
not by way of limitation, in which:
[0009] FIG. 1 is a schematic illustration of an underwater drilling
rig assembly located on a seabed;
[0010] FIG. 2 is a schematic top plan view of the underwater
drilling rig assembly;
[0011] FIG. 3 is a schematic illustration of the underwater
drilling rig assembly with a mast raised for drilling into the
seabed; and
[0012] FIG. 4 is a schematic view of a rig assembly of the
underwater drilling rig assembly with a drilling module coupled
thereto for drilling purposes.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Reference will now be made in detail to embodiments of the
invention, one or more examples of which are illustrated in the
accompanying drawings. Each example is provided by way of
explanation of the invention, not as a limitation of the invention.
It will be apparent to those skilled in the art that various
modifications and variation can be made in the invention without
departing from the scope or spirit of the invention. For instance,
features illustrated or described as part of one embodiment can be
used on another embodiment to yield a still further embodiment.
Thus, it is intended that the invention cover such modifications
and variations that come within the scope of the appended claims
and their equivalents.
[0014] Referring to FIGS. 1 and 2, a portion of an underwater
drilling rig assembly 10 is illustrated in a partially installed
and assembled condition. The underwater drilling rig assembly 10 is
depicted in a submarine environment. This environment, which may be
referred to as "undersea" or "subsea," can be any underwater
environment in which is there is a sea floor 12 and a water surface
14. Such environments include freshwater seas and lakes, as well as
offshore oceanic environments. The underwater drilling rig assembly
10 may be employed at a deepwater drilling location or in a
relatively shallow body of water. The underwater drilling rig
assembly 10 is particularly beneficial in bodies of water that are
prone to ice formation therein and bodies of water that are
commonly subjected to harsh environment conditions at the water
surface 14. The harsh environment conditions may include severe
weather, including the presence of high wind, large waves,
precipitation and/or bodies of ice, any of which would pose
challenges to a surface vessel 16.
[0015] The underwater drilling rig assembly 10 can be transported
to the drilling site by towing or by transport on a lift vessel.
Typically, the underwater drilling rig assembly 10 is transported
in a fully assembled form, however, transport as a plurality of
components with on-site assembly is contemplated. Irrespective of
the form of transport, the underwater drilling rig assembly 10 is
installed on the sea floor 12 and configured to carry out drilling
operations on the sea floor 12, thereby overcoming the issues
associated with surface vessel or platform drilling operations in
harsh environment conditions.
[0016] The following description pertains to a structure and method
to transport, install, and operate the underwater drilling rig
assembly 10. The underwater drilling rig assembly 10 includes a
hull 18 that is buoyant and configured to float at the water
surface 14, if desired. Ultimately, the underwater drilling rig
assembly 10 is lowered from the water surface 14 in a controlled
descent to a location proximate the sea floor 12 with any suitable
mechanism. The underwater drilling rig assembly 10 includes a
moonpool 19 that extends through the hull 18 and is positioned over
a desired drilling location on the sea floor 12. It is to be
appreciated that all aspects of the transport, installation, and
operation of the underwater drilling rig assembly 10 may be
monitored with an underwater remote operated vehicle (ROV) 20. The
ROV 20 typically provides a video feed to a human operator that
visually monitors the process.
[0017] The underwater drilling rig assembly 10 also includes a rig
assembly 22 operatively coupled to, and disposed on, the hull 18.
The rig assembly 22 includes a number of components and structures
that are typically associated with drilling operations. In one
embodiment, the underwater drilling rig assembly 10 is similar to a
jack-up structure, but the entire assembly is configured to be
submerged and placed on the sea floor 12, as described in detail
herein. The hull 18 is configured to be ballasted proximate the sea
floor 12. Extending from the hull is at least one, but typically a
plurality of legs 24 extending from the hull 18 toward the sea
floor 12. In one embodiment, three such legs are included to
provide desired stability, but more or less are contemplated. The
legs 24 are lowered to engage the sea floor 12 and the load of the
underwater drilling rig assembly 10 is transferred to the legs 24.
It is to be appreciated that the plurality of legs 24 bear the
overall load of the underwater drilling rig assembly, specifically
the hull 18 and the rig assembly 22. This is in contrast to a
wellhead supporting a drilling assembly. The legs 24 can be
adjusted to compensate for a sea floor region that is not level.
The adjustment, if needed, provides an overall leveling of the hull
18, and therefore the underwater drilling rig assembly 10 overall.
In one embodiment, a plurality of spud cans 26 are installed
proximate ends of the plurality of legs 24 to provide further
anchoring and self-leveling of the underwater drilling rig assembly
10, however, this may not be required in certain applications.
[0018] Referring now to FIG. 3, with continued reference to FIGS. 1
and 2, the rig assembly 22 includes a mast and pipe lifting arm
module 28. Upon proper securement of the underwater drilling rig
assembly 10 to the sea floor 12, a mast 30 of the mast and pipe
lifting arm module 28 is raised from the illustrated horizontal
position (FIG. 1) to a substantially vertical position (FIG. 3) to
facilitate various lifting and drilling operations performed by the
underwater drilling rig assembly 10. As shown, the mast 30 is
maneuverable between substantially horizontal and vertical
orientations. Such a feature may be particularly beneficial in
bodies of water having an ice keel that protrudes to depths of the
body of water that may interfere with the underwater drilling rig
assembly 10. If such a condition is detected, the mast 30 is simply
maneuvered to a substantially horizontal position. A pipe handling
unit 34 of the mast and pipe lifting arm module 28 is configured to
be pivoted from the horizontal position (FIG. 1) to facilitate
maneuvering of a drill pipe (not shown) to be operatively coupled
to the mast 30. A drill bit assembly (not shown) is lowered into a
desired position and operatively coupled to the mast 30.
[0019] A control unit 42 is installed at a location proximate the
sea floor 12 and the rig assembly 22. In the illustrated
embodiment, the control unit 42 is integrated with the rig assembly
22 on the hull 18. Alternatively, the control unit 42 may be placed
directly on the sea floor 12. The control unit 42 includes a
plurality of components configured to carry out various tasks
associated with overall operation of the underwater drilling rig
assembly 10. The specific tasks are numerous and the following are
merely illustrative of the contemplated tasks. The control unit 42
includes various lines, such as at least one return line 44
operatively coupled to the surface vessel 16 and the control unit
42. The return line 44 is configured to return fluids, such as
drilling fluid and waste fluid to the surface vessel 16 from the
underwater drilling rig assembly 10. Additionally, at least one
supply line 46 is operatively coupled to the surface vessel 16, as
well as one or more components of the rig assembly 22, including
the control unit 42. The supply line(s) 46 comprise a flow line to
provide drilling fluid and an electrical line to provide power to
the underwater drilling rig assembly 10. To facilitate routing of
fluid, the control unit 42 includes a pump configured to direct the
fluid in a desired direction. The control unit 42 further includes
a plurality of cables (not shown) extending from the control unit
42, each of the cables connected to components of the underwater
drilling rig assembly 10. Such a connection between the surface
vessel 16, the control unit 42, and various components of the
underwater drilling rig assembly 10 allows remote control of
various functions of the underwater drilling rig assembly 10. The
configuration of the lines extending between the control unit 42
and the surface vessel 16 is such that the surface vessel 16 does
not need to remain directly over the underwater drilling rig
assembly 10. By providing flexibility regarding the positioning of
the surface vessel 16, challenges associated with maintaining
precise position of the surface vessel 16 are avoided. This is
particularly advantageous in severe weather environments.
[0020] In addition to a physical connection with the
above-described lines and cables, a wireless connection may be
present between the control unit 42 and the surface vessel 16
and/or the components of the underwater drilling rig assembly 10.
By remotely controlling the underwater drilling rig assembly 10
with the surface vessel 16, it is not necessary to have human
operators in direct physical contact with the underwater drilling
rig assembly 10. In addition to remote control of the assembly,
numerous aspects of operation of the underwater drilling rig
assembly 10 may be automated, as is the case with onshore drilling
assemblies. In particular, an automated drilling mode is enabled
with the underwater drilling rig assembly 10. Once the underwater
drilling rig assembly 10 is fully installed and operational, the
drill bit assembly initiates drilling into the sea floor 12. After
reaching a sufficient depth with the drill bit assembly, a casing
may be installed within the hole and a blowout preventer (BOP) may
be run and installed proximate a wellhead of the hole.
[0021] Referring to FIG. 4, the underwater drilling rig assembly 10
is configured to receive various equipment modules (not shown) from
the surface vessel 16 or another vessel specially designed to
store, transport and deliver the modules to the underwater drilling
rig assembly 10. One such module 50 is generally illustrated and is
configured to be disposed on the hull 18 to interact with the mast
30 and pipe handling unit 34 of the mast and pipe lifting arm
module 28. The equipment modules are prepared for running and
drilling the well and casing that is run in the well when a
required well segment is complete.
[0022] Advantageously, the underwater drilling rig assembly 10 is a
highly automated unit that can be remotely operated by as little as
one human operator. The hull 18 rests on the sea floor 12, thereby
allowing loading of the other components to be on the base, rather
than on the well itself. Furthermore, based on the remote control
of the underwater drilling rig assembly 10, the surface vessel(s)
supporting the assembly are not required to be positioned directly
over the assembly and the well. This is particularly advantageous
in harsh weather conditions, including those where ice formation is
present at the water surface 14 of the body of water. Conducting
the drilling operations on the sea floor 12 overcomes several
obstacles with drilling in such environments. In deepwater drilling
locations, the above-described embodiments obviate the need for the
long length of a drilling riser that would normally extend from the
surface vessel 16 to the sea floor 12.
[0023] While the invention has been described in detail in
connection with only a limited number of embodiments, it should be
readily understood that the invention is not limited to such
disclosed embodiments. Rather, the invention can be modified to
incorporate any number of variations, alterations, substitutions or
equivalent arrangements not heretofore described, but which are
commensurate with the spirit and scope of the invention.
Additionally, while various embodiments of the invention have been
described, it is to be understood that aspects of the invention may
include only some of the described embodiments. Accordingly, the
invention is not to be seen as limited by the foregoing
description, but is only limited by the scope of the appended
claims.
* * * * *