GB2354782A

GB2354782A - Fibre optic monitoring of sand control equipment

Info

Publication number: GB2354782A
Application number: GB0020233A
Authority: GB
Inventors: Jr Edward J Zisk; Steven B Hodges
Original assignee: Baker Hughes Inc
Current assignee: Baker Hughes Holdings LLC
Priority date: 1999-08-17
Filing date: 2000-08-17
Publication date: 2001-04-04
Also published as: NO20004120L; NO20004120D0; AU5346900A; CA2316131A1; GB0020233D0

Abstract

The progress and quality of the sand control process in a wellbore 10 is monitored by optical fibres 16 that are wrapped around sand control devices 14 in various patterns at a density dependent upon the measurement resolution required. The fibre pattern may be a zig-zag, spiral, or longitudinal array or may be located in a conduit at 0 an 180 degrees around its circumference. The character of the light travelling along the fibre is used to determine downhole conditions such as pressure, temperature, strain, vibration, or acoustic recognition and employs techniques such as microbending, Raman backscatter, and optical time domain reflectometry. Integrated sensors for interferometry, grating, fluorescence, or photoelasticity may additionally be used with the fibres and an optical demodulator 18 is located at the well head. The fibre may be protectively housed in a circumferential or axial groove in the sand control equipment or alternatively the fibre may be wound to lie between raised portions on the surface (see figure 7).

Description

2354782 FUM OMC MOMTOPJNCr OF SA, M CONTROL EQUrPAIEW AA F Field of t1w

Invention ne invention relates to the oil production industry. More particallidy the iuv=tion relates to.monitoring and opfimiziug operation of sand control equipmant in productiem on wells.

Prior Art

Hydrocarbon fluids am produced frorn undaground TewTvom that are Smarally comPosed of such bydrocartem, sand, gravA clay, M% bcd=X eto Up= pumping hydrocarbon fluids ftoln ti,888 Wells, particulate matter prosag in the reservoir such w particulates of Omt; materfai noted =Y be produced along with the target fluid. III$ is ParUcularly a problem with respect to ml production.

To control the production of pardcuLift matmr, which damWt. equipmmt both in the subsudace =vironment and at the surface, I Sub in&stry has dMIOP4 generally known as,ss=dconbmr). 7te sand canto, sub industry employs ==W toolsin The dOwnhole wv==Mt which trap dw particulate matter much the way a f ilter does- Sand control equnent left= the amount of produced ptcifttematter, reduces damagO to the production equipment and alleviates thojob of Sepamling the parWulaW matter ftm dwired products M the pm&ced f IUMS, In order for sand control equipment to fdter the most soli4 the equipment needs to be initalled PrOPedY and then to continually and oVer time, ran effidentIr P itmua Iremlin OPtknized- Optimization of sand control equ#Mmt has ta&tiomMy bm a q=sft0n Of engineering before insWinuou Mh ffiat the equip=nt WM pwn)rm as 1 expected. Since the downhole enviro=ent is never a certainty however, it could not heretofore be clearly determined that the equipment set properly. Moreover, monitoring of the condition of sand control equipment over time has been problematic, Thus, the art is in need of a method and apparatus capable of confirming S setftg of the sand control equipment and monitoring its performance and condition in an ongoing ma=er.

SUMMABY OF THE MMM_ The present invention comprises a method and apparatus of actively monitoring the installation, integrity, and performance of sand control equipment in a production well. The method and apparatus of the invention enhance the ability of an oil production crew to c<mtrol unwanted R= that may occur during production. Mie instrument comprises optical fiber that is integral wW or attached to the inside or outside surfaces of tha sand control equipment. The optical fiber, or fibers, with or without integrated sensors, are employed to monitor key parameters during the ir"ation process to precisely locate the equipment In ft well, monitor all aspects offt installation/completion process, including but not limited to the addition of aggregate, and then monitoring-the integrity and performance of the operational assembly. Typical parameters to be monitored include, but are not limited to chemical species, vibration, acoustic recognition of an event pressure, temperature, strau density, and vibration. An embodiment of the instrument is comprises an optical fiber or fibea attached on the cirmmference of the sand control equipment in a configuration or pattern determined by the measurement point density required. Additional optic4d filw is then attached to the equipment during the installation of the equipment into the wall. Tim optical fiber assembly can comprise bare optical fiber, or fibers, with or without a Ywiety of coatings and buffers, or optical fiber(s) contained M' P, cable or tubular steel which may or may not be hermetically sealed depending upon desired longevity and performance of the optiefter, The optical fiber assembly can be protected by installing the fiber in channels in the equipment or by the equipment having protuberances to keep the fiber(s) from rubbing the wall of the well during numing. The optical fiber assembly is connected to a fiber optic sensing darnodulator either at the surface, ft wellhead (surfue or subsea) or 2 downhole.

During installation, the exact depth. of die mud control equipment can be deternifned by monitoring the length of the optical fiber from a known point to a discrete optical signah= within the fibM that signature being located in a section of fiber mo=tcd to the downhole, equipment As one of skill in the art is aware, a confident knowledge of location of a downhole, tool is both elusive and invaluable.

This feature of the invention is thmfbre of great benefit to the art BRW DESMMMO_N OF TEM MAWNGS Figure I is a schematic elevation view of a wellbore having completion and sand control equipment installed therein, said sand control equipment having the optical fiber system of the invention integrated therein; Figure 2 is an entuWA viewof a portion of Figure I which illustrates optic fibers wrapped wound the sand control eqaipment; is Figure 3 is a view of an altemate wrapping pattern of the invention; Figure 4 is another alternate embodiment of the inventiou; Figure 5 is yet another ahmmate embodiment of the invention; Figure, 6 is a pers;mctive schemado view showing one arrangement for protecting the optic fibers employed in the iuvention; Fig= 7 is a perspective view showing an alternative an=gement for protecting the optic fibers employed in the invention; and Figure 8 is a perspective view showing anotber alternate arrangement fbr protecting the optic fibers employed in the invention.

D_ETAUM-DW--CWFU-ONOFM I It is important to note that one or more fibers are employable in the inventin which may be amnged. mi one or more of the configurations discussed hereunder without &Tarftg from 1he scope of the invention, Referring to Figure 1, one of ordinary skill in the art will recognize the depiction of a wellbore 10 and installed equipment therein. The equipment includes packers 12 and sand control devices 14 which may be of the added aggregate "a or ft no-added-aggregate type without affecting the function or components of the 3 invention. Optical Mors 16 are also visible in Figure 1. in orda to appreciate, tbo pattern of opticalfibers in Figure I reference is made to Figure 2 wherein the wrapped fiber 16 is more easily appreciated. The density of the wrapped fiber 16 is dependent upon the measurement resolution required and spacial resolution of the fiber optic demodulator used in the invention. Mw equipmeit at issue is a fiber optic sensing denzodulator 18 (Figure 1) which is illustrated at ft well head or the mirWc but which could be placed in an alternate location downhole, may, for example, require one meter of fiber to resolve a condition. In this case, the wrapping pattern must place ono meter of thefiber in each area to be monitored. This may require that 1he fiber be densely wrapped or may allowa. less dense wrap depending upon what is to be momtored, Likmse, a demoduktor with lugher resolution capacity nught need only.25 meters in each location being monitored.

Also viable in Figure 2 is sand control equipmmt segment 14 joint area, 20 where segments of sand control equipment are joined. Prokrably in connection with the inventiot, the fiber 16 may be continuous or optically comimW by a connector (not shown) over this joint area 20. Eitha method is acceptable and Is dictated by oirounisuawas ratlier tban by &wtion. One of ordinary skill in the art is equipped to determine which method is best for this particular application.

Refting now to Figurc 3, a very dense fiber optic pattern is illustmW which allows for monitoring of small locations on sand contrW equipment 14. The pattern employs both a zig zag pattern and a longitudinal array of fiber 16. This may be the same fiber or different fibers. The embodiments of Figures 4 and 5 also provide varying density of monitoring, varying cost and complwtity. Figure 4 provides a longitudinally back and forth pattem of fiber 16 while Figure 5 merely employs fiber 16 in a conduit 22 at 0 and 180 degrees around the circumference of sand control equipment 14.

Referring to Figures 6-8, it is important to note three alternative embodiments to protect the fiber during monitoring. Specifically referring to Figure 6 first sand control equipment 14 is provided with a groove 24 spiraling along the outside surface thereof as shown. It should be noted however that the groove could be located parallet to the longitudinal a3ds of equipment 14 or in anoer pattern if desired, The groove 24 is preferably of dimetsions at least slightly larger than the optic4l fiber to 1 4 be used so that said fiber will be completely eAveloped within the groove and therefore be protected from impact or abrasion during monitoring. In diis embodiment the reduction capability of the demodulator to be employed must be known so that the groove 24 is at an appropriate spacing to render the system effective. in another embodim=t, referring to Figure 7, a plumlity of raised portions (protuberances) 26 aTe extending ftm. an outer surface of sand control equipment 14. The arrangement provides additional flexibility since the fiber 16 may be laid nound the cirownfereum of the equipment 14 in whaUmw density it is needed. Many different density levels are possible with the embodiment of Figure 7 while maig a protective cavironment for fiber 16. A tbird protective environment for fiber 16 Is illustrated in Figure 8. In this embodiment the fiber 16 is actuaRy homed within the sand control equipment 14 in a conduit 28. Conduft 28 need only be large enough to house fiber 16 without deforming the some. The conduit may be in any desired configuration including but not limited to straight or spiraled.

In operation, the invention efflectively and actively monitors the installation of sand control equipment, its integrity over time and the perfbrnimee of ftt equipment. During installation, an exact depth of the sand control equipment is obtainable using a discrete optical signatum in thefiber at the location of the downhole equipment and the -length of the fiba optic cable that has entered the wellbore. In order to Maintain the integrity of the installation and performance fliereot parameters such as chemical species presen4 vibration, acoustic recognifion, pressirre. Umiperature. sftin, and densitr way be queried by the optical demodulator 18 through f1ber 16 directly or through integrated sensors. If done directly, monitoring may take place through monitoring point or distnbuted measur-and along the equipment direefly through the fiber itself uft for example inicrobending (pressure) Raman Backscatter and optical time domain reflectometry (temperature). Fmomples of integrated sensor used include (all paraxneters) grating, (RU pmmetm) florescence (mostly chemical species. viscosity and temperature) and photoelasticity (temperature, acceleration, vibration and rotational position). Front the various measmments, progress and quality of the mad control process can be monitored. The system also provides a real time check on the sand control equipment and will aleTt surface personnel to problenis before damage is done.

It should be, noted that the optical fiber 16 can be outside the sand equipm=t as shown in figure 6 or inside as shown in Figure 8 or cm be in a separate tool (not shown) deliverable to the sand control equipment through the tubing, In any of these embodiments all of the pv=eters toted can be sensed and immedialu knowledge of the conditions dowrahole are Itnown at the surface. Fiber could be sacmd to the equipment in such a way to allow the flow field of the sand and carrier flufd to induce mechanical loads, dynamic =&or sUtic, on the fiber. Example: A turbulcut flow of fluid would cause a loosely mounted fiber to vibrate. When the flow stop.% static sand present, the fiber becomes stationary. Monitoring of the fibers movernmt/or force applied can be used to determine where sand is present This is usefal to determine progms of alpha and beta waves.

While preferred embodiments have been shown and desen'bed, various modificatons and substitations may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood tUt the present

Claims

fnvention has be,= described by way of illustration and not limitation.

What is claimed!

6 CLAIM 1. A method for monitoring sand control equipment comprising:

causing a sufficient length of fiber to be in an immediate vicinity of sand control equiI=ent; and Monitoring character of light traveling along said fiber.

CLAW2. A method for monitoring sand control equipment as claimed in claim 1 wherein said method farther comprises determining a condition Telativa to said sand control equipment bawd upon said character of light traveling along said fiber.

CLAIM 3. A method for monitoring sand control equipment as claimed in claim I wherain aid monitoring is catried out using one of microbending, R =an backsoatter and optical tbw domain TefleCtDruCtly.

CLAIM 4. A method for monitoring sand control equipment as cl4imed in claim I wherein said monitoring is carried out by employing iftgrated sensors to sense one of in! erferometry, grating, florescence and photoelasticity.

CLAIM 5. A downhole sand control equipment monitoring arrangement comprising at least one optic,41-fiber disposed in the immediate vicinity of Bad control equipment.

CLAIM 6. A downhole sand control equipment monitoring an-ang=ent as claimed in claim 5 wherein said at lead one fiber is in contact with said sand control equipment CLAIM 7. A downhole sand control equipment monitoring azrangement as claimed in claim 5 wherein said at lead one fiber is wrapped around sand equipment CLAIM 8. A downhole, sand control equipment monitoring arrangerneat as clainied in claim 7 wherein said at least one fiber is in a helical pattern.

7 CLAIM 9. A downhole, sand control equipment monitoring arrangement as claimed in claim 7 wherein said at least one fiber is in a zig zag pattem CLAIM 10. A, downhole sand control equipment monitoring azrangement as claimed in claim 5 wherein said at least one fiber is extended generally parallel to a longitudinal axis of the sand control equipment with which it is associated.

CLAW 11. A downhole sand control equipment monitoring arrangement its claimed in claim 5 wherein said at least one fiber is mainudned in a longitudinal back and fDrth arrangement relative to a length of said situd control equipment.

CLAIM 12. A downhole sand control equipment monitoring arrangement as claimed in claim 5 wherein said at least one fiber is two fibers positioned substantially in paraDel to one anothmr and to an axis of the sand control equipment with which they are associated and located about 180' EtparL CLAIM 13. A downhole, sand control equipment mordwring arrangement as claimed in claim 5 wherein said at least onefiber is housed in a groove in said sand control equipment.

CLAIM 14. A downhole sand control equipment monitoring arrangement as claimed in claim 13 wherein said groove is substantially circumforentially disposed on said sand control equipment.

CLAIM 15. A downhole sand control equipment monitoring arrangem=t as claimed in claim 13 wherein said groove is substantially axially disposedon said sand control equipment.

CLAIM 16. A downhole, sand control equipment monitorlug arrangement as claimed in claim 13 wherein said groove is of a set of dimensions sufficient to allow at least one fiber disposed therein to be recessed from a surface of said sand control equipment CLAIM 17. A downhole sand, cmtrol equipmut monitming a=ge3nent as claimed in claim 5 wherein said at IeW onefiber is disposed widdn a conduit.

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