U.S. patent application number 12/531898 was filed with the patent office on 2010-09-23 for system and method for performing intervention operations with a subsea y-tool.
Invention is credited to Andrea Sbordone, Rene Schuurman.
Application Number | 20100236786 12/531898 |
Document ID | / |
Family ID | 39591312 |
Filed Date | 2010-09-23 |
United States Patent
Application |
20100236786 |
Kind Code |
A1 |
Sbordone; Andrea ; et
al. |
September 23, 2010 |
SYSTEM AND METHOD FOR PERFORMING INTERVENTION OPERATIONS WITH A
SUBSEA Y-TOOL
Abstract
A technique utilizes a Y-tool (22) mounted at a subsurface
installation (24) for subsea intervention operations. The Y-tool
comprises a guide branch (30) and an open water branch (28) that
each allows movement of intervention tools to the subsea
installation. A tubular guide member can be coupled to the guide
branch to enable movement of equipment down through the tubular
guide member and into the Y-tool. Alternatively or in combination,
other equipment can be moved down through the open water and into
the Y-tool through the open water branch. The Y-tool further
facilitates deployment of conveyances through the tubular guide and
the guide branch to enable engagement of the conveyance with an
intervention tool deployed through the open water and into the open
water branch of the Y-tool.
Inventors: |
Sbordone; Andrea; (Rio de
Janeiro, BR) ; Schuurman; Rene; (Stavanger,
NO) |
Correspondence
Address: |
SCHLUMBERGER OILFIELD SERVICES
200 GILLINGHAM LANE, MD 200-9
SUGAR LAND
TX
77478
US
|
Family ID: |
39591312 |
Appl. No.: |
12/531898 |
Filed: |
March 18, 2008 |
PCT Filed: |
March 18, 2008 |
PCT NO: |
PCT/IB08/03332 |
371 Date: |
April 30, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60908101 |
Mar 26, 2007 |
|
|
|
Current U.S.
Class: |
166/360 |
Current CPC
Class: |
E21B 33/076 20130101;
E21B 17/015 20130101 |
Class at
Publication: |
166/360 |
International
Class: |
E21B 41/08 20060101
E21B041/08 |
Claims
1. A method of delivering tools to a subsea well, comprising:
forming a Y-tool with a base branch, a guide branch, and an open
water branch; mounting the base branch to a subsea installation;
coupling a tubular guide member between the guide branch and a
surface facility; connecting an intervention tool to a conveyance;
and deploying the intervention tool and the conveyance through the
open water branch.
2. The method as recited in claim 1, further comprising moving a
Christmas tree plug through the open water branch.
3. The method as recited in claim 1, wherein coupling comprises
coupling a spoolable compliant guide between the guide branch and
the surface facility.
4. The method as recited in claim 3, wherein coupling comprises
coupling the spoolable compliant guide to an intervention
vessel.
5. The method as recited in claim 1, wherein coupling comprises
coupling a riser system between the guide branch and the surface
facility.
6. The method as recited in claim 1, wherein deploying comprises
deploying the intervention tool with a diameter too large to fit
through the tubular guide member.
7. The method as recited in claim 1, further comprising positioning
a lubricator to enable deployment of an intervention tool string
into a pressurized installation.
8. The method as recited in claim 1, wherein forming comprises
forming the open water branch with seal members positioned to
selectively seal the intervention tool within the Y-tool.
9. The method as recited in claim 2, further comprising locating a
dynamic seal to maintain a pressure tight seal against a wireline
or slickline conveyance member during an intervention
operation.
10. A method for performing an intervention operation, comprising:
mounting a V-tool, having a base branch, a guide branch, and an
open water branch, to a subsea installation; coupling a tubular
guide member between the guide branch and a surface facility;
moving an intervention tool and a conveyance through an interior of
the tubular guide member and into the Y-tool through the guide
branch; and delivering the intervention tool and the conveyance
through the subsea installation and into a well for performance of
the intervention operation.
11. The method as recited in claim 10, wherein delivering comprises
delivering the intervention tool on a coiled tubing conveyance.
12. The method as recited in claim 10, wherein coupling comprises
coupling a spoolable compliant guide between the guide branch and
the surface facility.
13. The method as recited in claim 10, further comprising locating
a dynamic seal to maintain a pressure tight seal against, the
conveyance during the intervention operation.
14. The method as recited in claim 10, further comprising
positioning a lubricator to enable deployment of the intervention
tool into a pressurized installation.
15. A system for use in subsea intervention operations, comprising:
a subsea installation; and a Y-tool having a base branch mounted to
the subsea installation, the Y-tool further having a guide branch
and an open water branch positioned to provide separate inlets for
intervention related equipment.
16. The system as recited in claim 15, further comprising a tubular
guide coupled to the guide branch and extending upwardly toward a
surface location.
17. The system as recited in claim 15, further comprising a spool
able compliant guide coupled to the guide branch.
18. The system as recited in claim 15, wherein the subsea
installation comprises a lubricator positioned below the
Y-tool.
19. The system as recited in claim 15, further comprising a dynamic
seal positioned to form a seal with a conveyance that moves through
the guide branch.
20. The system as recited in claim 15, further comprising a dynamic
seal positioned to form a seal with a conveyance that moves through
the open water branch.
21. A method for facilitating an intervention operation,
comprising: mounting a Y-tool over a subsea installation;
connecting a guide between the Y-tool and a surface facility; and
moving equipment through the Y-tool and into the subsea
installation from both a guide branch and an open water branch of
the Y-tool.
22. The method as recited in claim 21, wherein connecting comprises
connecting a riser system between the Y-tool and the surface
facility.
23. The method as recited in claim 21, wherein connecting comprises
connecting a spoolable compliant guide between the Y-tool and a
surface intervention vessel.
24. The method as recited in claim 21, wherein moving comprises
moving a conveyance through the guide and moving an intervention
tool through the open water for connection to the conveyance within
the Y-tool.
25. The method as recited in claim 24, further comprising holding
the intervention in a tool holder while the conveyance is connected
to the intervention tool.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present document is based on and claims priority to U.S.
Provisional Application Ser. No. 60/908,101, tiled Mar. 26,
2007.
BACKGROUND
[0002] The retrieval of desired fluids, such as hydrocarbon based
fluids, is pursued in subsea environments. Production and transfer
of fluids from subsea wells relies on subsea installations, subsea
flow lines and other equipment. Additionally, preparation and
servicing of the subsea well relies on the ability to conduct
subsea intervention work. Subsea intervention work involves
numerous challenges not normally faced when working on land wells
or fixed offshore platforms.
[0003] Intervention in subsea wells often is performed from a
floating platform or ship, and access to the subsea well is
achieved by a variety of techniques. In many applications, the
intervention operation is performed with wireline, slickline or
other cable-type conveyance methods. For example, tools can be
conveyed from a surface vessel to a subsea installation through
open water. With this technique, the tools are conveyed into a
subsea lubricator with a dynamic seal at the top of the lubricator.
Such operations are sometimes called "open water" or "riserless"
operations and require that the equipment be moved through the open
sea water. Additionally, these types of open water operations
cannot be performed with coiled tubing while maintaining a coiled
tubing injector at the surface.
[0004] In another technique, tools are conveyed through a tubular
riser or guide system connecting a surface intervention vessel with
the subsea installation. However, the tubular system can provide
technical constraints, such as a limited internal diameter. The
technical restraints are problematic in moving certain types of
intervention tools to the subsea installation. For example,
movement of large diameter tools through the tubular system to the
subsea installation can be difficult or impossible.
SUMMARY
[0005] In general, the present invention, provides a technique for
subsea intervention operations which utilizes a Y-tool mounted at a
subsurface facility. The Y-tool comprises a guide branch and an
open water branch to enable movement of intervention tools to the
subsea installation along two different paths. For example, a
tubular guide member can be coupled to the guide branch to enable
movement of equipment down through the tubular guide member and
into the Y-tool. Other equipment can be moved down through the open
water and into the Y-tool through the open water branch. The
availability of two different paths greatly enhances the ability to
carry out a wide variety of intervention operations at a subsea
well.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] Certain embodiments of the invention will hereafter be
described with reference to the accompanying drawings, wherein like
reference numerals denote like elements, and:
[0007] FIG. 1 is a schematic front elevation view of a subsea
intervention system, according to an embodiment of the present
invention;
[0008] FIG. 2 is a schematic front elevation view similar to that
of FIG. 1 but showing another example of an intervention operation,
according to an embodiment of the present invention; and
[0009] FIG. 3 is a schematic front elevation view similar to that
of FIG. 1 but showing another example of an intervention operation,
according to an embodiment of the present invention.
DETAILED DESCRIPTION
[0010] In the following description, numerous details are set forth
to provide an understanding of the present invention. However, it
will be understood by those of ordinary skill in the art that the
present invention may be practiced without these details and that
numerous variations or modifications from the described embodiments
may be possible.
[0011] The present invention generally relates to a technique for
performing intervention operations. The technique utilizes a side
entry tool or Y-tool deployed proximate a subsea installation to
facilitate a wide range of intervention procedures. The Y-tool
comprises a base branch that is mounted to the subsea installation
to direct intervention equipment into the subsea installation and
the subsea well. At its upper end, the Y-tool comprises a plurality
of branches through which tools can be directed into the Y-tool and
subsequently down into the subsea installation and subsea well. In
many applications, the Y-tool comprises a pair of upper branches
that can be referred to as a guide branch and an open water branch
designed to receive and direct various types of intervention
equipment.
[0012] The side entry tool is referred to as a Y-tool because of
the divergent upper branches that can be used to direct equipment
downwardly to the base branch and subsequently into the subsea
installation and well. However, the Y-tool can be constructed in a
variety of configurations, shapes and sizes. The various branches
can be of different lengths and/or diameters, and two or more upper
branches can serve as guides to the lower branch. Use of the Y-tool
at the subsea installation enables use of a greater variety of
intervention procedures than otherwise afforded by conventional
intervention equipment. In some applications, for example, a
tubular guide member is connected to the guide branch of the
Y-tool, and the other, divergent, branch extends to the open
water.
[0013] The Y-tool allows an operator to select whether equipment is
deployed to the subsea well through the tubular guide member or
through the open water. Often the intervention operations can be
facilitated by deploying some equipment through a tubular guide
member and other equipment through the open water. The ability to
utilize different access points to the well helps optimize
deployment of tools into the subsea installation, particularly when
intervention operations are conducted with different conveyances,
e.g. wireline, slickline and coiled tubing. The Y-tool also enables
deployment of intervention tools, e.g. tool strings, that, are too
large for movement through the tubular guide member. In this latter
example, the intervention tool can simply be deployed through the
open water, moved into the Y-tool via the open water branch, and
positioned within a lubricator that is either part of the Y-tool or
positioned below the Y-tool. A coiled tubing conveyance or other
conveyance is routed down through the guide branch of the Y-tool
and connected to the intervention tool within the enclosed,
pressure protected Y-tool/lubricator. In other applications, the
subsea Y-tool enables both the efficient removal of crown plugs
from horizontal Christmas trees and the transfer of those plugs
through open water.
[0014] Although specific examples of intervention systems utilizing
a Y-tool are described below, it should be noted that many
configurations and methodologies related to the intervention
operations and use of the Y-tool are possible. Furthermore, the
subsea intervention operations can be performed in conjunction with
a variety of subsea installations, including subsea wells, subsea
flowlines and other subsea systems.
[0015] Additionally, the subsea installation and subsea Y-tool are
designed to prevent pressurized fluids from escaping the subsea
installation during the intervention operation. Accordingly, the
subsea installation and the Y-tool have appropriate sets of seals
and valves that can be selectively actuated to maintain a pressure
tight envelope that prevents the escape of pressurized borehole
fluids. A wide variety of such pressure control valves, seals and
other devices can be used to contain the pressurized environment
within the subsea installation and Y-tool.
[0016] The system and methodology described herein enable the use
of open water and tubular guide member deployment techniques
according to a variety of flexible procedures. Thus, a service
company can switch from one technique to another without major
hardware changes. Also, the techniques can be used individually or
in combination during interventions performed on a subsea
installation to optimize operational efficiency and to reduce the
occurrences of hardware deployment and hardware retrieval between
the surface facility, e,g. surface intervention vessel, and the
seabed.
[0017] By way of example, the use of a Y-tool intervention system
enables wireline, slickline and coiled tubing operations to be
performed with the same deployed hardware. The system also enables
open water wireline and slickline operations without disconnection
of the tubular guide member. Coiled tubing conveyance systems also
can be used with large tools that can not be moved through the
guide member. The need for subsea wet connection of wireline and
slickline big diameter took is eliminated, because such tools can
be conveyed through the open water. Similarly, the need for an open
water wireline or slickline kill line can be eliminated, because
the tubular guide member can be used for this purpose. Horizontal
Christmas tree plugs can be removed to the open water with a
wireline or slickline while allowing immediate access with coiled
tubing, via the tubular guide member, without deploying any
additional hardware. Similarly, no additional hardware need be
deployed or retrieved to switch between wireline/slickline open
water operations and coiled tubing operations. The methodology also
facilitates the flushing of the lubricator for open water wireline
operations, because the coiled tubing/tubular guide member can be
used rather than providing an additional service Also, a coiled
tubing conveyance can be provided as a contingency for wireline or
slickline operations without requiring additional deployment or
retrieval of hardware. In each of these applications, the
efficiency of the intervention operation is improved and the risk
of exposure to hazards related to the subsea intervention is
reduced due to the reduced number of activities required to perform
the intervention procedures.
[0018] Referring generally to FIG. 1, one example of an
intervention system 20 is illustrated according to an embodiment of
the present invention. In this embodiment, system 20 comprises a
subsea Y-tool 22 proximate a subsea installation 24. By way of
example, subsea installation 24 may comprise a wellhead, a
flowline, a Christmas tree, or another type of subsea installation
that is subjected to intervention procedures. The subsea Y-tool may
be mounted above subsea installation 24 to direct intervention
equipment into the subsea installation. In the example illustrated,
subsea Y-tool comprises a base branch 26 mounted to subsea
installation 24. The Y-tool further comprises at least two upper
branches, such as an open water branch 28 and a guide branch
30.
[0019] A tubular guide member 32 is coupled between subsea
installation 24 and a surface facility 34, such as an intervention
vessel. The tubular guide member 32 may be in the form of a riser
system comprising, for example, a rigid, flexible or compliant
riser that connects the surface facility 34 to the subsea
installation 24 via the Y-tool. The tubular guide member 32 also
may comprise a compliant guide such as a spoolable compliant guide
having a hollow interior along which equipment may be guided into
subsea installation 24. The lower end of tubular guide member 32 is
connected to guide branch 30 of subsea Y-tool 22.
[0020] Subsea installation 24 also may comprise a lubricator 36
which allows deployment of an intervention tool string into a
pressurized installation that prevents escape of pressurized
fluids. The lubricator 36 may he formed as an integral part of
subsea Y-tool 22, or the lubricator 36 may be a separate component
positioned beneath the Y-tool 22. Depending on the specific
application, the lubricator can be installed at a variety of
positions in the Y-tool, below the Y-tool, or above the Y-tool. The
pressurized installation can be achieved by a variety of valves and
seals positioned in various arrangements. For example, a plurality
of subsea valves 42 can be positioned in the subsea installation 24
beneath the Y-tool 22. Additionally, a subsea valve 44 and a
dynamic seal 46 can be positioned in the open water branch 28
proximate the net to the open water branch. Similarly, a subsea
valve 48 can be positioned in guide branch 30 of Y-tool 22. A
dynamic seal 50 also is positioned to cooperate with guide branch
30 and can be located in a variety of positions in guide branch 30
or along tubular guide member 32. In the illustrated embodiment,
dynamic seal 50 is positioned generally at a lower end of the
tubular guide member 32 proximate an emergency disconnect 52.
[0021] Intervention operations can be performed in a variety of
subsea installations 24, and with a variety of configurations of
additional equipment connected on top of the subsea installation.
In the embodiment illustrated in FIG. 1, the subsea installation 24
comprises a subsea wellhead 54 that may include a Christmas tree
and other components positioned above a subsea well 56. The other
components may include subsea valves 42 and related devices, such
as a subsea lubricating seal and a blowout preventer having one or
more cut-and-seal rams able to cut through the interior of the
subsea installation and seal off the subsea installation during an
emergency disconnect. The subsea installation 24 also may comprise
additional blowout preventers as well as a subsea stripper assembly
positioned above the blowout preventers. The number and type of
devices mounted on a given subsea installation can vary from one
subsea application to another.
[0022] In FIG. 1, an example of one use of the Y-tool to facilitate
an intervention operation is illustrated. In this example, an
intervention operation is performed through the open water branch
28 of Y-tool 22. An intervention tool 58, such as a tool string or
other well equipment, is lowered through the open water by a
conveyance, such as a cable-type conveyance 60. By way of example,
conveyance 60 may be a wireline, slickline or other cable-type
conveyance deployed and retrieved via a crane 62 mounted on surface
facility 34.
[0023] The intervention tool 58 is connected to conveyance 60,
lowered through the open water and into open water branch 28 of
Y-tool 22. The intervention tool 58 continues to travel down
through the base branch 26, through a tool holder 62, and through
subsea installation 24 until entering the borehole of subsea well
56. One or more dynamic seals provide a pressure barrier around the
cable-type conveyance 60 as it moves up and down in subsea well 56.
The dynamic sealing can be formed by dynamic seal 46 in open water
branch 28 or by dynamic seals incorporated at subsea valves 42.
During this type of intervention operation, guide branch 30 can be
left open in some applications or sealed off to prevent movement of
fluids from the subsea installation 24 into tubular guide member
32. By way of example, guide branch 30 can be sealed by closing
subsea valve 48. It should be noted, the open water branch 28 also
can be used to provide a pathway for the removal of crown plugs
from horizontal Christmas trees before an intervention operation
and to reinstall the crown plugs at the end of the intervention
operation.
[0024] Another intervention operation is illustrated in FIG. 2. In
this example, intervention tool 58 is deployed along the interior
of tubular guide member 32 by a conveyance 64. By way of example,
conveyance 64 may comprise wireline, slickline or coiled tubing
depending on the particular type a intervention operation being
performed. In some applications wireline or slickline can be used
to deploy intervention tool 58, e.g. a tool string, through the
tubular guide member, provided the intervention tool string has an
outer diameter small enough to pass through the guide member. If
conveyance 64 comprises coiled tubing, the coiled tubing can be
coupled to intervention tool 58 by an appropriate connector 66.
[0025] In many coiled tubing intervention operations, the
intervention tool 58, e.g. tool string, has a configuration that is
difficult or impossible to move through tubular guide member 32. In
these applications, intervention tool 58 can be lowered through the
open water and into open water branch 22 by the cable-type
conveyance 60. The intervention tool 58 is continually lowered into
the lubricator 36 and held by tool holder 62, as illustrated in
FIG. 3. The cable-type conveyance 60 is then disconnected from the
intervention tool, e.g. tool string, and coiled tubing conveyance
64 is lowered toward the intervention tool 58 through tubular guide
member 32. The coiled tubing conveyance 64 is engaged with
intervention tool 58 via connector 66 which may be in the form of a
subsea tool wet connector. Once connected, tool holder 62 is
released to enable the lowering of intervention tool 58 through
subsea installation 24 and into subsea well 56 via coiled tubing
conveyance 64.
[0026] The examples described above are just a few examples of the
many ways in which Y-tool 22 can be utilized to facilitate a
variety of intervention operations. Additionally, the Y-tool 22 is
amenable to use with a wide variety of methodologies and
cooperating devices. For example, the dynamic seals 46, 50 that are
used in cooperation with the open water branch 28 and guide branch
30, respectively, can be retrievable dynamic seals. Alternatively,
the dynamic seals can be non-retrievable seals which are
temporarily opened to full bore for passage of intervention tools
and then closed on the conveyance to establish a pressure tight
barrier.
[0027] The open water branch 28 also can be sealed of by a variety
of pressure barriers, including valves and plugs. Additionally,
guide branch 30 can include or work in cooperation with emergency
disconnect 52 which enables release of tubular guide member 32 from
Y-tool 22 in the event of an operational emergency where the
surface intervention vessel must disconnect from the subsea
installation 24. Valves can he placed above, below, and/or above
and below the emergency disconnect 52 to prevent the escape of
fluids into the sea water. Numerous additional and alternate
devices can be utilized in cooperation with the Y-tool to
facilitate a great range of intervention operations. The relative
orientation of the guide branch and the open water branch as well
as the relative size of the branches also can vary. For example,
the open water branch may have a larger diameter than the guide
branch for some applications. The length of the Y-tool branches
also can vary to accommodate many types of intervention tools.
[0028] Although only a few embodiments of the present invention
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 invention.
Accordingly, such modifications are intended to be included within
the scope of this invention as defined in the claims.
* * * * *