Fiber optic bundle, method and system for incorporation into cable to support applications in well

Abstract

Fiber optic bundles, methods, and systems for incorporation into a cable to support applications in a well are disclosed. A bundle cable of an optical fiber bundle includes: a first optical fiber line; and a second optical fiber line twisted with the first optical fiber line at a zero twist angle. The method includes: supplying a first optical fiber cable; and twisting a second optical fiber line at the first optical fiber line at a zero-degree twist angle in a coupling manner to form an optical fiber bundle. The system includes a stranding device for stranding optical fiber cables with one another at a zero twist angle.

Description

[0001] This application is a divisional application of patent application No. 202080047571.4, filed on June 29, 2020, entitled "Stranded Fiber Optic Cable". Background Technology

[0002] Exploration, drilling, and completion of oil and gas wells, as well as other wells, are typically complex, time-consuming, and ultimately very expensive undertakings. Given these costs, greater emphasis is placed on efficiency related to completion and maintenance throughout the well's lifespan. Therefore, improvements in efficiency, for example, in logging, perforation, or many interventional applications, can be highly beneficial, especially as well complexity and depth increase, often exceeding 30,000 feet.

[0003] One way to transport downhole tools into the well for logging, perforation, or various other intervention applications is by using steel cables or wire cables. Steel cables typically have telemetry and power capabilities, while wire cables may have a smaller profile and limited functionality. More specifically, wire cables can only provide a structural transport tool for vertically lowering tools or tool strings into the well.

[0004] However, with increasing focus on efficiency, fiber optic capabilities can be provided for both steel cables and wire cables. In this way, wire cables can be equipped with real-time telemetry capabilities. Furthermore, for both steel cables and wire cables, adding fiber optic lines facilitates location-specific temperature and pressure or strain measurements using traditional distributed strain and temperature (DST) techniques. This allows for a degree of real-time intelligence and potential response via transport vehicles. In other words, it enables control of vehicles from oilfield surface equipment, and real-time communication between vehicles and surface equipment is also available.

[0005] Traditional methods of combining one or more fiber optic cables into steel cables or wire cables typically involve loosely placing the wires within the surrounding structure of the line. For example, the fiber optic portion of the assembly is often referred to as FIMT (Fiber in a Metal Tube). From a manufacturability perspective, this packaging is practical. Additionally, allowing the fiber within the tube to float or migrate during application can help prevent damage to the fiber caused by strain due to the mechanical bending and torque of the surrounding tube.

[0006] Unfortunately, loosely placing optical fibers within metal conduits sacrifices accuracy in data acquisition from the fiber. For example, because the fiber may be significantly displaced from the conduit's structure, a bend in the conduit may not translate into an immediately detectable or identical bend in the fiber. Similarly, leaving a gap between the wire and the conduit means that the temperature exposed to the conduit at a given downhole location may not easily translate to the fiber. For the same reason, at any given location in the cable, the wire may be physically and tightly connected to the conduit at any given moment. At such times and locations, strain or temperature measurements taken through the wire may actually be quite accurate. Of course, the operator and / or ground equipment cannot interpret these moments of relatively increased accuracy relative to any other moment. Therefore, this fact only complicates matters.

[0007] Of course, looseness can be eliminated and the fiber optic cable can be treated as any other cable component. For example, sheathed cables can be directly encased in metal tubing without any intermediate gaps or gaps. Theoretically, this architecture would improve the accuracy of the data obtained from the cable. Unfortunately, this design often causes micro-bending breaks in the fiber optic cable. This is especially true when the cable is inserted into the well at considerable depth. In such cases, the resulting tension on the surrounding structure can compress the cable, causing damage even without any excessive bending. Therefore, operators often have no choice but to rely on inaccurate fiber optics rather than using easily faulty, disposable fiber optic cables. Summary of the Invention

[0008] A fiber optic cable for deployment in a well is disclosed. The cable comprises multiple fiber optic lines twisted together to form a bundle. An encapsulation is then provided around the bundle, such that the bundle and lines mechanically respond to the encapsulation in a coupled manner.

[0009] A fiber optic bundle for incorporation into a cable to support applications in wells is disclosed. The bundled cable includes: a first fiber optic line; and a second fiber optic line twisted with the first fiber optic line at a zero-degree twist angle.

[0010] In some embodiments, the lines are spirally intertwined with each other.

[0011] In some embodiments, the cable is one of the FIMT construction and coupling configurations.

[0012] In some embodiments, during the application in the well, the coupled cable is one of a hermetically sealed cable and a fiber optic mechanical response cable.

[0013] In some embodiments, the coupled cable further includes: at least a third optical fiber stranded with the first and second cables; and a filler support located between the optical fibers.

[0014] In some embodiments, the filler support has a material selected from the group consisting of: polyethylene terephthalate, aramid yarn, polymer filler yarn, polymer monofilament, fluoropolymer, and polyetheretherketone.

[0015] In some embodiments, the coupled cable includes gap filler surrounding the bundle to form a filled bundle.

[0016] In some embodiments, the coupled cable includes a second filler bundle.

[0017] In some embodiments, the coupled cable includes a sheath surrounding the filler bundle.

[0018] In some embodiments, the sheath also incorporates one of a polymer layer, a cladding layer, a conductor, an armor wire, and a strength member.

[0019] A method is also disclosed. The method includes: supplying a first optical fiber; and coupling a second optical fiber to the first optical fiber at a zero-degree twist angle to form an optical fiber bundle.

[0020] In some embodiments, the twisting includes spirally winding the threads together.

[0021] In some embodiments, the stranding includes using information from a tension sensor to guide the take-up unit to drive the stranding.

[0022] In some embodiments, the method further includes encapsulating the bundle structure to form a hermetically tight coupling structure with fiber mechanical responsiveness.

[0023] In some embodiments, the method further includes: incorporating the encapsulated bundle into a cable; and using the cable to perform an application in a well.

[0024] In some embodiments, the bonding includes sheathing the bundle with one of a polymer, cladding, conductor, armor wire, and strength member.

[0025] A system for manufacturing optical fiber bundles is also disclosed. The system includes a stranding device for stranding optical fiber lines together at a zero-degree twist angle.

[0026] In some embodiments, the stranding device includes: a separator for guiding the wires; and a gathering die for winding the wires together.

[0027] In some embodiments, the system further includes a dedicated tension sensor for each wire.

[0028] In some embodiments, the system further includes a take-up unit for driving the stranding, the driving of the take-up unit being based on information from the tension sensor. Attached Figure Description

[0029] Figure 1 This is a side view diagram illustrating an application where multiple optical fibers are joined together to form a micro-bundle.

[0030] Figure 2A yes Figure 1 A side view of the application, in which additional interstitial filler is introduced to form micro-bundles.

[0031] Figure 2B It has gap filler Figure 2A Side cross-sectional view of the microbeam.

[0032] Figure 3 It is an overview of the oil field, depicted in a configuration of cables. Figure 2B Application of micro-beam support in wells.

[0033] Figure 4A yes Figure 2A A side view of the application, showing the additional central filler introduced to form micro-bundles.

[0034] Figure 4B It has a central packing material. Figure 4A Side cross-sectional view of the microbeam.

[0035] Figure 5A yes Figure 4A A side view of the application, in which an additional sheath is introduced to supply the microbeams to form Figure 3 The cable.

[0036] Figure 5B yes Figure 3 and Figure 5A Side cross-sectional view of the cable.

[0037] Figure 6A It has an added cladding. Figure 5A Side cross-sectional view of micro-bundles and cables.

[0038] Figure 6B It is an additional architecture with symmetrical conductors and a sheath. Figure 2B Side cross-sectional view of the microbeam.

[0039] Figure 6C It is an additional architecture with asymmetric conductors and a sheath. Figure 2B Side cross-sectional view of the microbeam.

[0040] Figure 6D It is an additional structure with strength components, armored wires, and cladding. Figure 2B Side cross-sectional view of the microbeam.

[0041] Figure 6E It is an additional structure with conductors, cladding, and sheath. Figure 2B Side cross-sectional view of the microbeam.

[0042] Figure 6F It is an additional structure with conductors in a coaxial configuration incorporated into the cable. Figure 2B Side cross-sectional view of multiple microbeams.

[0043] Figure 7 This is a flowchart outlining an implementation scheme for manufacturing a cable with micro-bundles having multiple optical fibers twisted together. Detailed Implementation

[0044] The implementation scheme is described with reference to certain cable and downhole applications. Specifically, the implementation schemes described herein focus on applications such as steel cable or wire used for logging applications in wells. However, alternative applications using such cables can take advantage of the unique characteristics detailed herein. As used herein, the term "wire" refers to applications running on a delivery line with a total outer diameter substantially less than 0.25 to 0.5 inches, while steel cable applications may use cables with a slightly larger profile. In any case, considerable benefits can be achieved as long as the cable has multiple optical fibers twisted together in a coupled manner, which translate into a mechanical response during application.

[0045] Now for specific reference Figure 1 This diagram illustrates a side view of an application where multiple fiber optic lines 110, 120, and 130 are coupled into a micro-bundle 100. As shown, lines 110, 120, and 130 are intertwined in a coupling manner with direct contact. That is, compared to conventional FIMTs, the relatively fine fiber optic lines 110, 120, and 130 are not only physically coupled to adjacent structures, but they are also physically coupled to adjacent structures of another line 110, 120, or 130. More specifically, lines 110, 120, and 130 can be wound together with a zero-degree twist angle as shown for structural reinforcement. Thus, these fiber optic features, which are typically more susceptible to microfracture damage due to bending, can be strengthened by coupling them together. This is referred to herein as providing a zero-degree twist angle. This can also be considered as a right angle, and the term "zero-degree twist angle" is intended to include right angles.

[0046] Continue to refer to Figure 1Wires 110, 120, and 130 can pass through individual tension sensors 160, 165, and 167 and be guided to stranding device 150. More specifically, device 150 includes a separator 175 and a gathering die 180 configured to guide and spirally wind wires 110, 120, and 130 into the microbundle 100 pulled by take-up unit 115, respectively. The close coordination between gathering die 180 and take-up unit 115 is guided by information from tension sensors 160, 165, and 167, which helps determine the winding and stranding of wires 110, 120, and 130 to ensure self-reinforcing assembly of microbundle 100. A cutting die 190 is also provided to terminate microbundle 100 once a predetermined length is reached.

[0047] Due to the described coupling of lines 110, 120, and 130, the assembled micro-bundle 100 can be used in FIMT-type fiber optic lines with improved resistance to breakage caused by microbending. However, with the increased resistance to such fiber damage, more accurate fiber readings can occur when the micro-bundle 100 is incorporated into a more coupled structural embodiment detailed below.

[0048] Figure 1 The microbeam 100 protects the underlying lines 110, 120, and 130 from large and small bends, allowing for low optical budgets and strain during manufacturing and operation. Figure 3 (As shown below). As detailed below, the concept can be used in single-core, coaxial, three-core, four-core, and / or seven-core cable configurations, with or without armor, and in half-piece, single-piece, or clad types. Like other fiber optic lines, the Micro-Bundle 100 can be optimized for multiaxial strain, vibration, pressure, and / or temperature measurements, combined with conductivity characteristics. Therefore, when positioned in a well, it can provide data and power transfer functions to and from the surface. With improved functionality and resistance to microfractures, the Micro-Bundle 100 can be longer and deployed to greater well depths. Again, avoiding FIMT architectures allows for the construction of cables using the Micro-Bundle 100 in hermetically sealed configurations.

[0049] Now for reference Figure 2A and Figure 2B This illustrates the additional introduction of interstitial filler to form filled micro-bundles 200. Figure 1 A side view of the application. Specifically, Figure 1 The microbeams 100 pass through the filling device 225 to supply polymer filler 250, thus obtaining filled microbeams 200. Therefore, as... Figure 2B As shown in the cross-section, the gap space can be filled with filler 250, so that the filled micro-beams 100, for example, in Figure 3The cable 300 features improved processability, as detailed below. It should be noted that the fiber optic structure 275 is sheathed in the depicted embodiment, even before the introduction of the filler 250. However, this is not necessarily required.

[0050] In one embodiment, the polymer filler 250 is silicon. Of course, other suitable materials can be used. In any case, filling the gaps in the initial microbeams 100 can help prevent gas migration and provide support and protection for application purposes, such as... Figure 3 As shown. In the illustrated embodiment, the filling device 225 is also used to cure, for example, by ultraviolet (UV) radiation or heating, when the filled microbeams 200 begin to leave the device 225. However, alternative curing techniques may be employed before the filled microbeams 200 reach the take-up reel 115.

[0051] Now for specific reference Figure 3 And refer to other sources Figure 2A and Figure 2B The diagram shows an overview of oilfield 301, where a cable 300 composed of filled micro-bundles 200 is deployed in well 380 to support logging applications. Assuming the filled micro-bundle cable 300 includes fiber optic lines 110, 120, and 130 coupled to each other, the entire cable 300 can include fiber-optic mechanically coupled connections. That is, compared to conventional FIMT assemblies, Figure 3 The cable 300 in well 380 may include optical fibers physically coupled to the structure and extending to the outer surface of the cable 300. Fiber optic sensing may be more direct and / or more "mechanically responsive." This is because there is no hollow tube structure that would be achieved by directly twisting the wires 110, 120, and 130 together.

[0052] Continue to refer to Figure 3 The cable 300 is specifically suspended within the well 280 to deploy logging tools 385 for logging applications. Thus, as the tool 385 traverses various formations 375, 395, well characteristic information can be acquired. Therefore, logging applications and tool 385 can benefit from the telemetry capabilities via the optical fiber of the cable 300. For example, as... Figure 3 As shown, oilfield 301 is equipped with a large number of surface devices 350, such as truck 310, for mobile cable delivery from drum 315. However, in the illustrated embodiment, truck 310 also houses a control unit 330, which may house a processor and power supply for interfacing with downhole logging tools 385. Therefore, instead of using tools limited to downhole batteries and recorders to run logging applications for later analysis, applications can be run where tools 385 are provided with sufficient power and units 330 acquire data from them in real time.

[0053] To effectively operate this real-time downhole application as described above, cable 300 features a unique architecture that enhances the accuracy of the obtained fiber optic readings without applying undue stress to the fiber optic components due to the aforementioned zero-twist coupling. See further references. Figure 2A and Figure 2B The term "mechanical response" is used to emphasize the significant reduction or elimination of the use of hollow tubes to house the filled micro-bundles 200. That is, as detailed below in the embodiments, the surrounding structure of the cable 300 is in direct contact with the micro-bundles 200. Therefore, for example, fiber optic detection of mechanical cable bending can be determined with greater accuracy. However, it is also worth noting that mechanical responsiveness is not the only fiber optic detection enhanced due to the elimination of the hollow tube structure. In fact, pressure, temperature, or any other detection that can be determined from the fiber optic components is also enhanced. For example, consider how reducing or eliminating the hollow space improves the fiber's sensitivity to temperature readings from well 380. Essentially, the cable 300 is constructed with a unique coupling method and in a manner that protects the delicate fiber optic components without the hollow tube. Therefore, fiber optic detection is enhanced without causing undue damage to the components.

[0054] Now for reference Figure 4A and Figure 4B This illustrates another filled micro-bundle 200 of the filler support 400. That is, in conjunction with the stranding of fiber optic lines 110, 120, and 130, the strands of the filler support 400 can be coupled to lines 110, 120, and 130. More specifically, as shown... Figure 4B As shown in the cross-section, the filler support 400 located in the region between lines 110, 120, and 130 can be uniquely positioned to increase structural support. This is particularly advantageous when there are three or more lines 110, 120, and 130 and this region is naturally generated. In this way, in addition to the support obtained from coupling with each other at the aforementioned zero-degree twist angle, lines 110, 120, and 130 can also obtain support from the filler support 400. The filler support 400 can be polyethylene terephthalate, aramid yarn, polymer-filled yarn, polymer monofilaments such as fluoropolymers or polyetheretherketones, or other suitable materials.

[0055] Now for reference Figure 5A and Figure 5B Complete as follows Figure 3The cable 300 shown may be a bundle of micro-bunches 200 filled with a polymer sheath 500. For example, in the illustrated embodiment, the micro-bunch 100 may be fabricated as a filled micro-bunch 200 with a filler support 400, and then sheathed at an extrusion device 550 similar to a filling device 225. In fact, in the illustrated embodiment, similar to how the filler 250 is cured at the filling device as described above, the curing of the sheath 500 may also occur at the extrusion device 550. Of course, as detailed below, various other architectural configurations can benefit from the availability of the coupled fiber optic micro-bunches 100 as described above.

[0056] Now for reference Figures 6A to 6F The filled micro-bundles 200 are shown to be incorporated into various different architectural configurations of the cable 300, for example, they can be deployed in such... Figure 3 The application shown. Figure 6A The implementation plan is, for example, Figure 5A and Figure 5B The sheathed cable 300 includes a filler support 400, which has been further processed to add an outer metal sheath 601.

[0057] For details, please refer to the following: Figure 6B Symmetrical electrical conductors 619 are positioned around the filled micro-bundle 200. A cladding 617, along with additional peripheral conductors 610 and a polymer sheath 615, has been provided again. Of course, as... Figure 6C As shown, the inner conductor 625 can be asymmetrical or "wedge-shaped" rather than symmetrical, and the cladding can be located outside the inner conductor and the peripheral conductor. (Reference) Figure 6D The internal conductors 650 can be symmetrical, but their number must be odd.

[0058] refer to Figure 6E By using internal strength members 639, armor lines 630, cladding 637, and an outer polymer sheath 635, capacitance may not be the focus. Furthermore, as... Figure 6F As shown, the filled micro-bundle 200 can even provide two copies. Therefore, readings from different sides of the cable 300 can be analyzed. In the illustrated embodiment, a conductor 670, supplementary optical fiber, and additional armor wire 680 embedded in a polymer sheath 690 are also employed.

[0059] Regardless of the specific implementation, the availability of zero-twist coupling micro-bundles 200 between individual optical fibers means that they can be filled and used to construct any number of mechanically responsive fiber optic cables 300. Cables 300 can not only have enhanced fiber durability but also be virtually void-free, thus reducing the likelihood of gas migration during application. Consequently, cables 300 themselves can also offer enhanced reliability.

[0060] Now for reference Figure 7 The diagram illustrates a flowchart outlining an embodiment for manufacturing a cable with a micro-bundle having multiple intertwined optical fibers. As indicated at 710 and 730, at least two optical fibers are supplied such that they can be intertwined. Therefore, as indicated at 750, a zero-degree twist angle is employed, allowing fine optical fibers to be typically used for reinforcement. As indicated at 770, the resulting bundle can be encapsulated with additional structures. Thus, a mechanically responsive optical fiber assembly can be reliably used in downhole applications (see 790).

[0061] The implementation scheme detailed above avoids the looseness and hollowness found in conventional FIMT constructions. Therefore, the provided fiber optic line implementation scheme exhibits a mechanical response to increase the accuracy of downhole detection. Furthermore, the implementation scheme provides enhanced reliability to the fiber optic cable by utilizing multiple wires coupled to each other at a zero-degree twist angle. Thus, the fiber optic cable includes structural reinforcement for enhanced durability and allows for practical and reliable use of the line in well applications.

[0062] The foregoing description has been presented with reference to the currently preferred embodiments. Those skilled in the art to which these embodiments pertain will understand that modifications and alterations to the described structure and operating methods can be practiced without meaning to depart from the principles and scope of these embodiments. In any case, the foregoing description should not be construed as relating solely to the precise structures described and shown in the accompanying drawings, but should be understood to be consistent with and support the following claims, which will have the most complete and fair scope.

Claims

1. A fiber optic bundle for incorporation into a cable to support applications in wells, the bundled cable comprising: First fiber optic line; The second optical fiber is twisted with the first optical fiber at a zero-degree twist angle.

2. The fiber bundle of claim 1, wherein the wires are spirally wound around each other.

3. The fiber bundle as claimed in claim 1, wherein the cable is one of the FIMT construction and coupling configurations.

4. The fiber bundle of claim 3, wherein during the application in the well, the coupled cable is one of an airtight cable and a fiber optic optical-mechanical response cable.

5. The fiber bundle of claim 3, wherein the coupled cable further comprises: At least a third optical fiber line, which is twisted together with the first and second lines; as well as A filler support located between the optical fibers.

6. The optical fiber bundle of claim 5, wherein the filler support has a material selected from the group consisting of: polyethylene terephthalate, aramid yarn, polymer filler yarn, polymer monofilament, fluoropolymer, and polyetheretherketone.

7. The fiber bundle of claim 3, wherein the coupled cables include gap filler surrounding the bundle to form a filled bundle.

8. The fiber bundle of claim 7, wherein the coupled cable includes a second filler bundle.

9. The fiber bundle of claim 7, wherein the coupled cable includes a sheath surrounding the filler bundle.

10. The fiber bundle of claim 9, wherein the sheath further incorporates one of a polymer layer, a cladding layer, a conductor, an armor wire, and a strength member.

11. A method comprising: Supply of first-class fiber optic cables; as well as The second optical fiber is twisted at the first optical fiber with a zero-degree twist angle in a coupling manner to form an optical fiber bundle.

12. The method of claim 11, wherein the twisting comprises spirally winding the wires together.

13. The method of claim 11, wherein the stranding includes using information from a tension sensor to guide the take-up unit to drive the stranding.

14. The method of claim 11, further comprising encapsulating the bundle structure to form a hermetically tight coupling structure having fiber mechanical responsiveness.

15. The method of claim 14, further comprising: The bundle of the encapsulation is then incorporated into the cable; as well as The cable is used to perform the application in the well.

16. The method of claim 14, wherein the bonding comprises sheathing the bundle with one of a polymer, a cladding, a conductor, an armor wire, and a strength member.

17. A system for manufacturing an optical fiber bundle, the system comprising a stranding device for stranding optical fiber lines together at a zero-degree twist angle.

18. The system of claim 17, wherein the stranding device comprises: Divider plate, used to guide the lines; as well as A gathering die is used to wind the wires together during the twisting process.

19. The system of claim 17, further comprising a dedicated tension sensor for each wire.

20. The system of claim 19, further comprising a take-up unit for driving the stranding, the driving of the take-up unit being based on information from the tension sensor.

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