EP2225801A1 - Purging of fiber optic conduits in subterranean wells - Google Patents
Purging of fiber optic conduits in subterranean wellsInfo
- Publication number
- EP2225801A1 EP2225801A1 EP07870010A EP07870010A EP2225801A1 EP 2225801 A1 EP2225801 A1 EP 2225801A1 EP 07870010 A EP07870010 A EP 07870010A EP 07870010 A EP07870010 A EP 07870010A EP 2225801 A1 EP2225801 A1 EP 2225801A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- conduit
- downhole
- conduits
- purging
- optical line
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Ceased
Links
- 238000010926 purge Methods 0.000 title claims abstract description 57
- 239000000835 fiber Substances 0.000 title abstract description 4
- 230000003287 optical effect Effects 0.000 claims abstract description 53
- 238000000034 method Methods 0.000 claims abstract description 33
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims description 13
- 239000001257 hydrogen Substances 0.000 claims description 13
- 229910052739 hydrogen Inorganic materials 0.000 claims description 13
- 238000004891 communication Methods 0.000 claims description 7
- 239000012530 fluid Substances 0.000 claims description 4
- 239000007789 gas Substances 0.000 claims description 4
- 230000002000 scavenging effect Effects 0.000 claims description 4
- 239000013307 optical fiber Substances 0.000 description 7
- 230000004927 fusion Effects 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000010793 Steam injection (oil industry) Methods 0.000 description 1
- 238000007792 addition Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009529 body temperature measurement Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000000254 damaging effect Effects 0.000 description 1
- 238000012217 deletion Methods 0.000 description 1
- 230000037430 deletion Effects 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/46—Processes or apparatus adapted for installing or repairing optical fibres or optical cables
- G02B6/50—Underground or underwater installation; Installation through tubing, conduits or ducts
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/18—Pipes provided with plural fluid passages
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/06—Measuring temperature or pressure
- E21B47/07—Temperature
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/12—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
- E21B47/13—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling by electromagnetic energy, e.g. radio frequency
- E21B47/135—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling by electromagnetic energy, e.g. radio frequency using light waves, e.g. infrared or ultraviolet waves
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
- G01N21/15—Preventing contamination of the components of the optical system or obstruction of the light path
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B47/00—Survey of boreholes or wells
- E21B47/01—Devices for supporting measuring instruments on drill bits, pipes, rods or wirelines; Protecting measuring instruments in boreholes against heat, shock, pressure or the like
- E21B47/017—Protecting measuring instruments
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
- G01N21/15—Preventing contamination of the components of the optical system or obstruction of the light path
- G01N2021/151—Gas blown
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/85—Investigating moving fluids or granular solids
- G01N21/8507—Probe photometers, i.e. with optical measuring part dipped into fluid sample
- G01N2021/8528—Immerged light conductor
Definitions
- the present invention relates generally to equipment utilized and operations performed in conjunction with subterranean wells and, in an embodiment described herein, more particularly provides for purging of fiber optic conduits in subterranean wells.
- optical fibers It is very important for optical fibers to be well protected when they are used in harsh, hostile environments, For example, in high temperature environments, such as in steam injection wells or other high temperature well environments, there are a variety of possibly damaging effects to guard against.
- One effect of high temperature environments on optical fibers is accelerated hydrogen darkening.
- an optical fiber can become unusable due to hydrogen darkening within a few days of its installation. Therefore, it will be appreciated that improvements are needed in the art of protecting optical fibers in hostile environments .
- a downhole optical sensing system and associated method are provided which solve at least one problem in the art.
- an optical fiber is installed within coaxial conduits for convenient purging of hydrogen from about the optical fiber.
- a purging medium is circulated downhole and returned from downhole via the coaxial conduits.
- a downhole optical sensing system is provided.
- the system includes at least one optical line and at least two tubular conduits. One conduit is positioned within the other conduit.
- the optical line is positioned within at least one of the conduits.
- a purging medium is flowed in one direction through one conduit, and is flowed in an opposite direction between the conduits.
- a method of purging a downhole optical sensing system includes the steps of: installing at least two conduits and an optical line in a well as part of the sensing system, one conduit being positioned within the other conduit, and the optical line being positioned within at least one of the conduits; and flowing a purging medium through the conduits in the well, so that the purging medium flows in one direction through one conduit and in an opposite direction between the conduits.
- FIG. 1 is a schematic partially cross-sectional view of a system and method embodying principles of the present invention
- FIG. 2 is an enlarged scale schematic partially cross- sectional view of the optical sensing system
- FIG. 3 is a schematic partially cross-sectional view of a method of purging the optical sensing system.
- FIG. 4 is a schematic partially cross-sectional view of an alternate method of purging the optical sensing system.
- FIG. 1 Representatively illustrated in FIG. 1 is an optical sensing system 10 and associated method which embody principles of the present invention.
- the system 10 in this example is used to sense fluid properties or other parameters in a wellbore 12.
- the principles of the invention may be used for other purposes, as well.
- a production tubing string 14 has been installed in the wellbore 12. Attached to the tubing string 14 during installation is a conduit assembly 16 and a sensor 18.
- the conduit assembly 16 and sensor 18 may be separately attached to the tubing string 14 (for example, using clamps, etc.), or the conduit assembly and/or the sensor 18 could be integrally formed with the tubing string 14.
- the conduit assembly 16 and/or sensor 18 could be installed in the wellbore 12 whether or not the tubing string 14 is also installed in the wellbore. Therefore, it should be clearly understood that the principles of the invention are not limited in any way to the details of the system 10 illustrated in the drawings or described herein. Referring additionally now to FIG.
- FIG. 2 an enlarged scale cross-sectional view of a portion of the system 10 is representatively illustrated.
- the conduit assembly 16 includes an inner conduit 20 and an outer conduit 22.
- Multiple optical waveguides or lines 24, 26, 28 are contained within the conduits 20, 22. Although three lines 24, 26, 28 are depicted in FIG. 2, any number of optical lines (including one) may be used.
- the lines 24, 26, 28 may be of the type known as optical fibers or any other type of optical waveguide.
- conduits 20 may be used. Although the conduit 20 is described for convenience herein as an “inner” conduit, another conduit could be contained within the conduit 20, and although the conduit 22 is described for convenience herein as an “outer” conduit, another conduit could be external to the conduit 22.
- the conduits 20, 22 may be made of any suitable material, such as stainless steel, polymers, composites, etc.
- the optical lines 24, 26 are preferably used for distributed temperature sensing (DTS), a technique well known to those skilled in the art, in which backscattered light is analyzed to determine the temperature distribution along optical lines or fibers. In this manner, the lines 24, 26 themselves comprise temperature sensors in the optical sensing system 10.
- DTS distributed temperature sensing
- the optical line 28 is preferably operatively connected to the sensor 18 (for example, via a fusion splice 30).
- the sensor 18 could be a sensor designed to detect a property at a single location, such as a pressure sensor.
- the sensor 18 could be an optical sensor (such as the pressure sensor described in U.S. Patent No. 7159468), or it could be another type of sensor.
- the splice 30 is preferably contained within a chamber 32.
- the chamber 32 is preferably connected between the sensor 18 and a lower end of the conduit assembly 16, for example, using pressure isolating fittings 34 at either end of a tubular housing 36.
- pressure isolating fittings 34 at either end of a tubular housing 36.
- other arrangements and configurations may be used in keeping with the principles of the invention.
- a conventional 180-degree turnaround 38 in the chamber 32 is operatively connected to the lines 24, 26, so that the lines and the turnaround form a continuous optical waveguide from a remote location (such as the earth's surface) to a downhole location, and back to the remote location.
- This arrangement permits more accurate double-ended (as opposed to single-ended) distributed temperature measurements to be obtained using the lines 24, 26.
- An acceptable turnaround for use in the system 10 is manufactured by AFL Telecommunications LLC of Duncan, South Carolina USA. Fusion splices (such as the fusion splice 30) may be used to connect the lines 24, 26 to the turnaround 38.
- the chamber 32 is in communication with the interior of the inner conduit 20, and in communication with the space 40 between the conduits 20, 22. In this manner, a continuous flow passage is formed from the remote location (such as the earth's surface, sea floor, etc.) to the downhole location at the chamber 32, and back to the remote location.
- the remote location such as the earth's surface, sea floor, etc.
- This configuration permits a purging medium 42 (see FIGS. 3 & 4) to be flowed in one direction downhole, and flow in an opposite direction uphole, in order to purge hydrogen from about the lines 24, 26, 28.
- the purging medium 42 could comprise gas (such as nitrogen or another inert gas, air, etc.), a liquid, gel, etc.
- the purging medium 42 could have hydrogen scavenging capability.
- FIG. 3 one method of purging the hydrogen from about the lines 24, 26, 28 in the conduit assembly 16 is representatively illustrated. This method utilizes a purging device 44 connected to an upper end of the conduit assembly 16 at the remote location.
- the purging medium 42 is flowed via a conduit 46 into an interior chamber 48 of the device 44.
- the chamber 48 is in communication with the space 40 between the conduits 20, 22.
- the purging medium 42 flows downhole through the space 40 between the conduits 20, 22, into the chamber 32 at the lower end of the conduit assembly 16, and then back uphole to the remote location via the interior of the inner conduit 20. In this manner, hydrogen is purged from about the lines 24, 26, 28 in the conduit assembly 16.
- FIG. 4 another method of purging the hydrogen from about the lines 24, 26, 28 in the conduit assembly 16 is representatively illustrated.
- This method utilizes a somewhat differently configured purging device 50 connected to an upper end of the conduit assembly 16 at the remote location.
- the purging medium 42 is flowed via the conduit 46 into an interior chamber 52 of the device 50.
- the chamber 52 is in communication with the interior of the conduit 20.
- the purging medium 42 flows downhole through the interior of the inner conduit 20, into the chamber 32 at the lower end of the conduit assembly 16, and then back uphole to the remote location via the space 40 between the conduits 20, 22. In this manner, hydrogen is purged from about the lines 24, 26, 28 in the conduit assembly 16.
- a downhole optical sensing system 10 which includes at least one optical line 24, 26, 28 and at least two tubular conduits 20, 22.
- One conduit 20 is positioned within the other conduit 22.
- the optical lines 24, 26, 28 is positioned within at least one of the conduits 20, 22.
- a purging medium 42 is flowed in one direction through one conduit 20, and flowed in an opposite direction between the conduits 20, 22.
- the optical line 28 may be operatively connected to a downhole sensor 18.
- the optical lines 24, 26 may comprise a downhole sensor.
- the optical lines 24, 26, 28 may be positioned within the inner conduit 20.
- the purging medium 42 may comprise a gas.
- the purging medium 42 may comprise a hydrogen scavenging medium.
- the purging medium 42 may be flowed downhole in a first direction and return uphole in a second direction.
- the purging medium 42 may be flowed downhole in the second direction and return uphole in the first direction.
- the system 10 may also include a downhole chamber 32 in fluid communication with an interior of the inner conduit 20 and an annular space 40 between the conduits 20, 22.
- the system 10 can include a 180-degree turnaround in the optical lines 24, 26 within the downhole chamber 32.
- the method includes the steps of: installing at least two conduits 20, 22 and at least one optical line 24, 26, 28 in a well as part of the sensing system 10, one conduit 20 being positioned within the other conduit 22, and the optical line 24, 26, 28 being positioned within at least one of the conduits; and flowing a purging medium 42 through the conduits in the well, so that the purging medium flows in one direction through one conduit 20 and in an opposite direction between the conduits 20, 22.
- the method may include operatively connecting the optical line 28 to a downhole sensor 18.
- the method may include utilizing the optical line 24, 26 as a downhole sensor.
- the method may include flowing the purging medium 42 downhole in one direction and returning the purging medium from downhole in the opposite direction.
- the method may include flowing the purging medium 42 downhole in the second direction and returning the purging medium from downhole in the first direction.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- General Physics & Mathematics (AREA)
- Remote Sensing (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geophysics (AREA)
- Optics & Photonics (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Health & Medical Sciences (AREA)
- Mechanical Engineering (AREA)
- Electromagnetism (AREA)
- Optical Measuring Cells (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Abstract
Description
Claims
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/US2007/089000 WO2009085044A1 (en) | 2007-12-28 | 2007-12-28 | Purging of fiber optic conduits in subterranean wells |
Publications (2)
Publication Number | Publication Date |
---|---|
EP2225801A1 true EP2225801A1 (en) | 2010-09-08 |
EP2225801A4 EP2225801A4 (en) | 2012-05-30 |
Family
ID=40824576
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP07870010A Ceased EP2225801A4 (en) | 2007-12-28 | 2007-12-28 | Purging of fiber optic conduits in subterranean wells |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP2225801A4 (en) |
BR (1) | BRPI0722346A2 (en) |
CA (1) | CA2709698C (en) |
WO (1) | WO2009085044A1 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7946350B2 (en) * | 2008-04-23 | 2011-05-24 | Schlumberger Technology Corporation | System and method for deploying optical fiber |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004066000A2 (en) * | 2003-01-15 | 2004-08-05 | Sabeus Photonics, Inc. | System and method for deploying an optical fiber in a well |
US20070122104A1 (en) * | 2005-11-29 | 2007-05-31 | Petrospec Engineering Ltd. | Method of preventing hydrogen darkening of optic fibre |
WO2007066146A2 (en) * | 2005-12-06 | 2007-06-14 | Sensornet Limited | Sensing system using optical fiber suited to high temperatures |
WO2008051945A2 (en) * | 2006-10-24 | 2008-05-02 | Afl Telecommunications Llc | Breathable downhole fiber optic cable and a method of restoring performance |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3111551A (en) * | 1960-05-13 | 1963-11-19 | Anaconda Wire & Cable Co | Fluid-cooled power cable |
US5275038A (en) * | 1991-05-20 | 1994-01-04 | Otis Engineering Corporation | Downhole reeled tubing inspection system with fiberoptic cable |
DE69531747D1 (en) * | 1995-07-25 | 2003-10-16 | Nowsco Well Service Inc | SECURED METHOD AND DEVICE FOR FLUID TRANSPORT WITH WINDED PIPE, WITH APPLICATION IN TESTING DRILL BODIES |
WO2004038173A1 (en) * | 2002-10-24 | 2004-05-06 | Shell Internationale Research Maatschappij B.V. | Temperature limited heaters for heating subsurface formations or wellbores |
GB2416394B (en) * | 2004-07-17 | 2006-11-22 | Sensor Highway Ltd | Method and apparatus for measuring fluid properties |
US7218820B2 (en) * | 2004-07-22 | 2007-05-15 | Welldynamics, Inc. | Method and system for providing a hydrogen diffusion barrier for fiber optic cables used in hostile environments |
US8000572B2 (en) * | 2005-05-16 | 2011-08-16 | Schlumberger Technology Corporation | Methods of manufacturing composite slickline cables |
-
2007
- 2007-12-28 WO PCT/US2007/089000 patent/WO2009085044A1/en active Application Filing
- 2007-12-28 BR BRPI0722346-3A patent/BRPI0722346A2/en not_active IP Right Cessation
- 2007-12-28 CA CA2709698A patent/CA2709698C/en not_active Expired - Fee Related
- 2007-12-28 EP EP07870010A patent/EP2225801A4/en not_active Ceased
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2004066000A2 (en) * | 2003-01-15 | 2004-08-05 | Sabeus Photonics, Inc. | System and method for deploying an optical fiber in a well |
US20070122104A1 (en) * | 2005-11-29 | 2007-05-31 | Petrospec Engineering Ltd. | Method of preventing hydrogen darkening of optic fibre |
WO2007066146A2 (en) * | 2005-12-06 | 2007-06-14 | Sensornet Limited | Sensing system using optical fiber suited to high temperatures |
WO2008051945A2 (en) * | 2006-10-24 | 2008-05-02 | Afl Telecommunications Llc | Breathable downhole fiber optic cable and a method of restoring performance |
Non-Patent Citations (1)
Title |
---|
See also references of WO2009085044A1 * |
Also Published As
Publication number | Publication date |
---|---|
EP2225801A4 (en) | 2012-05-30 |
CA2709698A1 (en) | 2009-07-09 |
BRPI0722346A2 (en) | 2014-03-18 |
CA2709698C (en) | 2013-05-14 |
WO2009085044A1 (en) | 2009-07-09 |
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