U.S. patent application number 13/089208 was filed with the patent office on 2011-10-06 for system and method for deploying optical fiber.
This patent application is currently assigned to SCHLUMBERGER TECHNOLOGY CORPORATION. Invention is credited to Robert Greenaway.
Application Number | 20110240314 13/089208 |
Document ID | / |
Family ID | 40637427 |
Filed Date | 2011-10-06 |
United States Patent
Application |
20110240314 |
Kind Code |
A1 |
Greenaway; Robert |
October 6, 2011 |
SYSTEM AND METHOD FOR DEPLOYING OPTICAL FIBER
Abstract
A technique is provided for utilizing optical fiber in a well
environment. A well system is combined with a tube-in-tube system
designed to protect one or more internal optical fibers. The
tube-in-tube system has an entry at one end and a turn around at an
opposite end to enable fluid flow between a flow passage within an
inner tube and a flow passage within an annulus between the inner
tube and a surrounding outer tube. An optical fiber is deployed in
and protected by the tube-in-tube system.
Inventors: |
Greenaway; Robert; (Frimley,
GB) |
Assignee: |
SCHLUMBERGER TECHNOLOGY
CORPORATION
SUGAR LAND
TX
|
Family ID: |
40637427 |
Appl. No.: |
13/089208 |
Filed: |
April 18, 2011 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
12136567 |
Jun 10, 2008 |
7946350 |
|
|
13089208 |
|
|
|
|
61047303 |
Apr 23, 2008 |
|
|
|
Current U.S.
Class: |
166/385 ;
166/242.2 |
Current CPC
Class: |
E21B 17/18 20130101;
E21B 47/135 20200501 |
Class at
Publication: |
166/385 ;
166/242.2 |
International
Class: |
E21B 19/00 20060101
E21B019/00 |
Claims
1. A method, comprising: deploying an optical fiber along a tubular
for flowing a hydrocarbon based fluid; positioning the optical
fiber within an inner tube; protecting the inner tube and the
optical fiber with an outer tube surrounding the inner tube; and
using a fluid to move the optical fiber through the inner tube.
2. The method as recited in claim 1, wherein using comprises
providing access to the inner tube at only one end of the inner
tube.
3. The method as recited in claim 1, wherein deploying comprises
deploying the optical fiber through wellbore hardware with only a
single penetration.
4. The method as recited in claim 1, wherein using comprises
pumping the fluid through the inner tube, through a turn around,
and through the outer tube external to the inner tube.
5. The method as recited in claim 1, wherein positioning comprises
positioning a plurality of optical fibers in a plurality of inner
tubes.
6. The method as recited in claim 1, further comprising placing a
splice along the inner tube and the outer tube while maintaining
pressure integrity along both a flow path within the inner tube and
a flow path along the annulus between the inner tube and the outer
tube.
7. The method as recited in claim 1, further comprising routing the
inner tube and the outer tube through a well head outlet.
8. A system, comprising: a well system; a tube-in-tube system
disposed along the well system, the tube-in-tube system having an
entry at one end and a turn around at an opposite end; and an
optical fiber deployed in the tube-in-tube system.
9. The system as recited in claim 8, wherein the well system
comprises a completion system deployed in a wellbore.
10. The system as recited in claim 8, wherein the tube-in-tube
system comprises an inner tube within an outer tube, further
wherein the optical fiber extends through at least one of the inner
tube and the outer tube.
11. The system as recited in claim 8, wherein a fluid is circulated
between a first flow passage through the inner tube and a second
flow passage along an annulus between the inner tube and the outer
tube.
12. The system as recited in claim 8, wherein the tube-in-tube
system further comprises a splice.
13. A method, comprising: placing an inner optical fiber tube
within an outer tube to create an inner flow path through the inner
tube and an outer flow path between the inner tube and the outer
tube; connecting the inner flow path with the outer flow path;
isolating the inner flow path and the outer flow path from the
surrounding environment; and deploying an optical fiber by
circulating a fluid along the inner flow path and the outer flow
path.
14. The method as recited in claim 13, further comprising
retrieving the optical fiber by reversing circulation of the
fluid.
15. The method as recited in claim 13, wherein connecting comprises
connecting the inner flow path and the outer flow path with a turn
around positioned downhole in a wellbore.
16. The method as recited in claim 13, further comprising
separately routing the inner flow path and the outer flow path
through a well head.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of U.S. application Ser.
No. 12/136,567, filed Jun. 10, 2008 entitled "System And Method For
Deploying Optical Fiber" which claims priority to U.S. Provisional
Application No. 61/047303, filed Apr. 23, 2008, incorporated herein
by reference.
BACKGROUND
[0002] Optical fibers are used for carrying signals in a variety of
applications, including telephony applications. The optical fibers
are installed into ducting by "blowing" the fiber through the
ducting. Generally, the ducting is open on both ends to allow the
fiber to be blown through the entire duct. In some well related
applications, fluid drag forces also have been used to install
fibers into individual control lines. However, well applications
can create difficulties in deploying and retrieving optical
fiber.
SUMMARY
[0003] In general, the present invention provides a system and
method for utilizing optical fiber in a well environment. A well
system is combined with a tube-in-tube system designed to protect
one or more internal optical fibers. The tube-in-tube system has an
entry at one end and a turn around at an opposite end to enable
fluid flow between a flow passage within an inner tube and a flow
passage created in the space between the inner tube and a
surrounding outer tube. An optical fiber is deployed in and
protected by the tube-in-tube system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] Certain embodiments of the invention will hereafter be
described with reference to the accompanying drawings, wherein like
reference numerals denote like elements, and:
[0005] FIG. 1 is a schematic illustration of a well related system
having a fiber optic system, according to an embodiment of the
present invention;
[0006] FIG. 2 is a front elevation view of a specific example of a
well system deployed in a wellbore with the fiber optic system,
according to an embodiment of the present invention;
[0007] FIG. 3 is a view of one example of a turn around used in the
fiber optic system illustrated in FIG. 1, according to an
embodiment of the present invention;
[0008] FIG. 4 is a partial, orthogonal view of one example of a
tube-in-tube arrangement used in the fiber optic system illustrated
in FIG. 1, according to an embodiment of the present invention;
[0009] FIG. 5 is a partial, orthogonal view of another example of a
tube-in-tube arrangement used in the fiber optic system illustrated
in FIG. 1, according to an alternate embodiment of the present
invention;
[0010] FIG. 6 is a view of one example of a splice that can be used
in the fiber optic system, according to an embodiment of the
present invention; and
[0011] FIG. 7 is a view of one example of a well head outlet that
can be used in the well system illustrated in FIG. 2, according to
an embodiment of the present invention.
DETAILED DESCRIPTION
[0012] 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.
[0013] The present invention generally relates to a system and
method for utilizing and protecting optical fibers in a variety of
well related applications. For example, a tube-in-tube technology
enables fiber optic deployment and replacement via fluid pumping.
The use of the tube-in-tube technology provides a single tubular
form that reduces the number of hardware penetrations in many
applications while providing greater protection to the optical
fiber.
[0014] The technique can be used in well related applications with
many types of equipment. For example, the fiber optic protection
system can be used in combination with various tubular well
components, including wellbores, well completions, pipelines,
flowlines, risers and other well related equipment. Additionally,
the unique design enables deployment and retrieval of a fiber optic
line when access is only available at one end of the system. In
many applications, the fiber optic line can be deployed and/or
retrieved via the use of fluid that may be pumped to create fluid
drag forces. Similarly, an inner tube of the tube-in-tube
arrangement can be deployed and/or retrieved via fluid drag forces
in at least some well related applications. The optical fibers can
be deployed independently, in groups, and/or as pre-fabricated
cable.
[0015] With respect to protection, the tube-in-tube technique not
only provides physical protection but also provides multiple
barriers against the influx of hydrogen. Hydrogen can attack and
cause deterioration of fiber optic lines, but the dual walls of the
tube-in-tube technology help block the hydrogen. Additionally,
fluid can be circulated through the tube-in-tube structure to expel
unwanted gases, e.g. hydrogen gases, which could otherwise degrade
the internal fiber optic line.
[0016] Referring generally to FIG. 1, a well system 20 is
illustrated according to one embodiment of the present invention.
In this embodiment, well system 20 comprises a tubular well
component 22 and a fiber optic line protection system 24 for
protecting one or more fiber optic lines 26 which may comprise
optical fibers and/or optical fiber cable. In this example, the
protection system 24 comprises a tube-in-tube system that provides
a plurality of fluid flow paths as well as providing fiber optic
line protection against physical damage and deleterious fluids.
Well system 20 also may comprise other well related hardware 28,
and the design of protection system 24 enables passage through
hardware 28 with a single penetration 30.
[0017] Tubular well component 22 may comprise a variety of well
related components, depending on the specific application utilizing
fiber optic line 26. For example, tubular well component 22 may
comprise a well completion, a wellbore tubular, a pipeline, a
flowline, a riser, or another type of well related component. The
tube-in-tube protection system 24 can be positioned along tubular
well component 22 in a variety of ways depending on the
application. For example, system 24 can be deployed across a well
completion, behind a well completion, across one or more
subterranean reservoirs, or as a free hanging member from a surface
exit of a well. In other embodiments, system 24 can be deployed
along an exterior, inside, or across a pipeline, flowline or riser.
As illustrated in FIG. 1, for example, the protection system 24 is
deployed along the exterior of tubular well component 22. However,
the protection system 24 also can be deployed within tubular well
component 22, as indicated by dashed lines.
[0018] In FIG. 2, one example of well system 20 is illustrated as
constructed for use in a wellbore environment. In this example,
tubular well component 22 comprises a tubing string having a well
completion 32 deployed in a wellbore 34. In some embodiments,
wellbore 34 is lined with a wellbore casing having perforations 38
that allow communication between wellbore 34 and a surrounding
formation 40.
[0019] Although well completion 32 may be constructed with a
variety of components and configurations, the illustrated
embodiment is provided as an example and comprises a packer 42, a
perforated tubing section 44, and a tubing bullnose 46. The
perforated tubing section 44 enables communication between wellbore
34 and an interior of well completion 32. In the embodiment
illustrated, protection system 24 comprises a tube-in-tube system
that extends through packer 42 via single penetration 30. The
overall well system 20 also may comprise a variety of components
and configurations, including, for example, a hangar 48 and a well
head 50. In this example, tubular well component 22 is suspended by
hangar 48 and extends downwardly into wellbore 34 from well head
50. Well head 50 may be positioned at a surface location 52.
[0020] Similarly, protection system 24 may comprise a variety of
components and may be arranged in various configurations. In the
embodiment illustrated, protection system 24 comprises tubes or
conduits 54 that extend downwardly along tubular well component 22
to a fluid turn around 56. The system 24 also may comprise one or
more splices 58 for splicing sections of tubing together while
maintaining the pressure integrity of the tubing 54. In the example
illustrated, tubing 54 encloses fiber optic line 26 and is routed
through both packer 42, via single penetration 30, and through
hangar 48 via another single penetration 30. The tubing 54 and
enclosed fiber optic line pass through well head 50 and out through
a well head outlet 60. Outside of well head 50, the fiber optic
line 26 can be joined with a surface cable 62 in a junction box 64
via a junction 66. The junction box 64 also may comprise pressure
seals used to seal the fiber optic line 26 to the tubing 54
containing the fiber optic line.
[0021] In FIG. 3, one example of fluid turn around 56 is
illustrated. Fluid turn around 56 is connected to a distal end of
tubing 54 and is used to sealingly lock together an inner tube 68
and an outer tube 70. (See also FIG. 4). The fluid turn around 56
anchors the inner tube 68 and the outer tube 70 at one end while
allowing fluid flow between the inner tube and the outer tube. The
fluid turn around 56 also is designed to maintain pressure
integrity with respect to the surrounding environment.
[0022] As illustrated in FIG. 3, one embodiment of fluid turn
around 56 comprises an outer housing 72 connected and sealed to an
inner structure 74 having crossover flow passages 76. Inner
structure 74 also comprises a recessed portion 78 sized to receive
outer tube 70, as illustrated. Inner tube 68 extends through
structure 74 into fluid communication with a cavity 80 formed
between outer housing 72 and inner structure 74. The inner
structure 74 is sealed against inner tube 68 by a seal member 82 on
one side of crossover flow passages 76, and inner structure 74 is
sealed against outer tube 70 by a seal member 84 on an opposite
side of passages 76. Seal members 82, 84 may be elastomeric or may
be metallic, e.g. metallic ferrules, to form metal-to-metal
seals.
[0023] Because fluid turn around 56 is sealed with respect to inner
tube 68 and outer tube 70, fluid can be flowed along flow passages
within inner tube 68 and within outer tube 70 without being
affected by surrounding fluid. For example, fluid can be flowed
down through inner tube 68 along an inner tube flow passage, as
represented by arrows 86. The fluid is discharged from inner tube
68 into cavity 80 and directed upwardly through crossover flow
passages 76 and into an outer tube flow passage, as represented by
arrows 88. The fluid can then be returned to, for example, a
surface location. In the embodiment illustrated, the outer tube
flow passage, represented by arrows 88, comprises an annulus formed
between inner tube 68 and outer tube 70.
[0024] The flow of fluid down through inner tube 68 can be used to
deploy fiber optic line 26, e.g. an optical fiber, as illustrated.
The flowing fluid carries or drags the fiber optic line down
through inner tube 68. Retrieval of the fiber optic line 26 can be
achieved simply by reversing the direction of flow and flowing
fluid down through outer tube 70 along flow passage 88, out through
crossover flow passages 76, through cavity 80, and up through inner
tube flow passage 86. It should be noted that in other
applications, the flow of fluid along passages 86, 88 can be used
to deploy fiber optic line into the annulus between inner tube 68
and outer tube 70. In some applications, the fiber optic line may
be deployed along both inner tube flow passage 86 and outer tube
flow passage 88 as a single optical fiber loop or as separate
optical fibers.
[0025] Referring again to FIG. 4, tubing 54 may be formed in
various configurations depending on the specific well application.
In the embodiment illustrated, for example, the single inner tube
68 is deployed within the outer tube 70, and fiber optic line 26 is
protected within the inner tube 68. In alternate embodiments, the
inner tube 68 may protect a plurality of fiber optic lines 26, or a
plurality of inner tubes 68 can be used to protect a plurality of
fiber optic lines 26, as illustrated in FIG. 5. Additional or
alternate fiber optic lines also can be routed along the space
between the one or more inner tubes 68 and the surrounding outer
tube 70. In many applications, outer tube 70 and inner tube 68 are
relatively small in diameter. By way of example, outer tube 70 may
be constructed with a diameter of about 1 inch or less and often
0.25 inch or less, and inner tube 68 may be constructed with a
diameter of 0.125 inch or less. The size of the inner tube 68
allows deployment of the inner tube 68 within outer tube 70 via
fluid drag forces, at least in some applications.
[0026] In FIG. 6, one embodiment of splice 58 is illustrated. In
this embodiment, splice 58 is used to splice sections of inner tube
68 and sections of outer tube 70. The splice is formed in a sealed
manner to prevent commingling of the fluid flowing along flow
passages 86 and 88 with each other or with the surrounding
environmental fluid. Splice 58 can be formed with a variety of
components and configurations depending on the well environment and
the configuration of overall protection system 24.
[0027] As illustrated, splice 58 comprises an outer housing 90 that
is sealingly engaged with sections of outer tube 70 via seal
members 92 and 94. An inner splice structure 96 is used to
sealingly engage sections of inner tube 68 via a lower seal member
98 and an upper seal member 100. Seal members 92, 94, 98, 100 may
be elastomeric or may be metallic, e.g. metallic ferrules, to form
metal-to-metal seals. Inner splice structure 96 is sized to fit
within an internal cavity 102 of outer housing 90 in a manner that
allows fluid flow past inner splice structure 96 between the inner
splice structure and the surrounding outer housing 90. Fluid flow
along inner tube flow passage 86 can freely move through the
sections of inner tube 68 and through inner splice structure 96.
The flow along outer tube flow passage 88 can freely move within
outer tube 70 along the exterior of inner tube 68 and through
splice 58 via the internal cavity 102 formed between inner splice
structure 96 and outer housing 90. The splice 58 enables sections
of tubes 68, 70 to be connected and anchored in place while
maintaining pressure integrity with respect to each fluid flow
path.
[0028] Referring generally to FIG. 7, one example of well head 50
and well head outlet 60 is illustrated. The well head outlet 60
enables tubes 68 and 70 to pass through the well head 50 while
maintaining the pressure integrity of the well. The outlet 60 also
enables separation of each flow passage, e.g. flow passage 86 or
88, from an individual tube into multiple flow access points while
anchoring the flow tubes 68 and 70 in place. The well head outlet
60 also can be used to isolate each tube 68, 70 separately and, in
some applications, to provide a pressure seal with respect to the
fiber optic line 26 once the fiber optic line is installed.
[0029] In the illustrated embodiment, well head outlet 60 comprises
a flange 104 by which the well head outlet 60 is connected to the
main structure of well head 50. The flange 104 comprises a passage
106 sized to receive outer tube 70 and to form a seal with outer
tube 70 via a seal member 108. The well head outlet 60 further
comprises an exterior housing 110 that is joined with flange 104 to
form a cavity 112. Outer tube 70 is in fluid communication with
cavity 112 and either discharges fluid into cavity 112 or receives
fluid from cavity 112.
[0030] Housing 110 further comprises a plurality of passages 114
for receiving tubing through which fluid flow is conducted. For
example, inner tube 68 may extend through one of the passages 114
while being sealed to housing 110 via a seal member 116. Another
passage 114 may receive a tubing 118 sealed to housing 110 via a
seal member 120. In the illustrated embodiment, cavity 112 provides
a fluid link between tubing 118 and outer tube 70. Accordingly,
fiber optic line 26 can be flowed into inner tube 68 through well
head outlet 60 and through protection system 24. The returning
fluid can be routed along the outer tube flow passage 88, out
through cavity 112, and through tubing 118. Retrieval of fiber opic
line 26 can be achieved by reversing the direction of fluid
flow.
[0031] The structure, size, and component configuration selected to
construct fluid turn around 56, splice 58, and well head outlet 60
can vary from one application to another. Similarly, the overall
configuration of protection system 24 can change and be adapted
according to the environment and types of well systems with which
it is utilized. Regardless of the specific form, however, the
protection system 24 is designed to provide simple hydraulic
connections that allow rapid make-up, and to require no fiber
splices during rig time. The tube-in-tube structure provides a
compact solution in which one main conduit or outer tube is
employed so as to have a minimal effect on hardware installation.
For example, only a single feed through port is required at
completion hardware such as packer 42.
[0032] Use of the tube-in-tube structure also allows fiber optic
line 26 to be deployed or removed without requiring a work over
rig. The optical fibers or fiber optic cable is simply deployed and
retrieved by fluid flow in a first direction or a reverse
direction. Fluid flow induced deployment and retrieval enables use
of a continuous line of optical fiber from a surface location to a
distal end of the protection system. Accordingly, the potential for
signal losses and for breakage is reduced by avoiding fiber
splices. Neutral fluids also can be used to purge inner tube 68 and
outer tube 70, thereby extending the life of the optical
fibers.
[0033] The tube-in-tube structure not only provides physical
protection but it also protects the fiber optic line 26 by
providing an additional hydrogen barrier. The additional hydrogen
barrier slows the rate at which hydrogen migrates to the fiber
optic line, thus prolonging the life of the system. The normal
process for hydrogen to diffuse through metal is in the form of
atomic hydrogen that results from the breakup of H2 molecules
during corrosion. However, once the hydrogen diffuses through the
outer tube 70 the H2 molecules normally re-form and must once again
dissociate to penetrate inner tube 68. Accordingly, the
tube-in-tube structure provides a redundant hydrogen barrier. The
structure also provides opportunities for the hydrogen to migrate
to the surface and/or to be removed by circulating fluid through
flow passages 86, 88 to flush hydrogen from the system.
[0034] 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.
Such modifications are intended to be included within the scope of
this invention as defined in the claims.
* * * * *