Patent Publication Number: US-2022221676-A1

Title: Hybrid electro-optical cable having a hydrogen delay barrier

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This claims priority to U.S. Ser. No. 63/137,244, titled “A Hybrid Electro-Optical Cable Having A Hydrogen-Delay Barrier” and filed Jan. 14, 2021, the entirety of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to a wellbore operation tools, and more particularly (although not necessarily exclusively), to a hybrid electro-optical cable with a hydrogen-delay barrier. 
     BACKGROUND 
     Wellbore operations can be used to explore and recover natural resources such as water, oil, and gas. Examples of wellbore operations can include cleaning operations, drilling operations, plugging operations, completion operations, and production operations. Sensing and measurement tools can be deployed downhole to measure conditions in the wellbore. As an example, optical cables may be used with sensing and measurement tools for distributed temperature sensing, distributed strain sensing, and distributed acoustic sensing during wellbore operations. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cross-sectional view of an example of a well system that includes a hybrid electro-optical cable according to one example of the present disclosure. 
         FIG. 2  is a cross-sectional schematic of an example of a hybrid electro-optical cable with insulated conductors and an optical fiber within a tube having a hydrogen-delay barrier according to some aspects of the present disclosure. 
         FIG. 3  is a cross-sectional schematic of an example of a hybrid electro-optical cable with a concentric insulated conductor and tube with a hydrogen-delay barrier according to some aspects of the present disclosure. 
         FIG. 4  is a cross-sectional schematic of another example of a hybrid electro-optical cable with insulated conductors and an optical fiber within a tube having a hydrogen-delay barrier according to some aspects of the present disclosure. 
         FIG. 5  is a cross-sectional schematic of an example of a hybrid electro-optical cable with multiple concentrically arranged insulated conductors and a tube with a hydrogen-delay barrier according to some aspects of the present disclosure. 
         FIG. 6  is a cross-sectional schematic of an example of a wireline-configured hybrid electro-optical cable with a hydrogen-delay barrier according to some aspects of the present disclosure. 
         FIG. 7  is a flowchart of a process for using a hybrid electro-optical cable to transmit data during a wellbore operation according to some aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Certain aspects and examples of the present disclosure relate to a hybrid electro-optical cable with a hydrogen-delay barrier to reduce hydrogen darkening. A hydrogen-delay barrier may delay permeation of hydrogen into a space that the hydrogen-delay barrier encapsulates. Hydrogen darkening may be a degradation of glass that can decrease an ability of an optical fiber to transmit optical signals. Hybrid electro-optical cables can be used for sensing during wellbore operations. A hybrid electro-optical cable can include one or more optical fibers in a tube and one or more insulated electrical conductors. The insulated electrical conductors can be used for providing power or telemetry to electric gauges, and the tube can support the optical fibers. The optical fibers can include glass, which may be susceptible to hydrogen darkening. 
     Enhanced backscatter fibers can provide increased backscattering above Rayleigh-limited backscattering levels, which, when included in a tube, can improve the signal-to-noise ratio of distributed acoustic measurements for reservoir diagnostics and vertical seismic profiling. Enhanced backscatter fibers may not have full coverage carbon coatings or other impermeable coating materials, and may thus be susceptible to hydrogen-permeation-induced attenuation or darkening. Without a hydrogen mitigation strategy, the enhanced backscatter fibers may darken and may provide inadequate return signal strength resulting in inaccurate sensing measurement over the life of a well. Other hybrid electro-optical cable designs typically include a fiber-in-metal tube that encapsulates carbon-coated fibers in a hydrogen scavenging gel. But, these designs may not be compatible with enhanced backscatter fibers, as the enhanced backscatter fibers used in examples of the present disclosure may involve an incomplete carbon coating or no carbon coating. 
     Some aspects of the present disclosure may provide a hybrid electro-optical cable with a hydrogen-delay barrier for reducing hydrogen permeation into a core of the hybrid electro-optical cable. The hydrogen delay barrier may be impermeable to hydrogen over extended period of time, such as decades or centuries, at elevated wellbore temperatures and pressures. The hydrogen-delay barrier can allow an enhanced backscatter fiber to be deployed in a hybrid electro-optical cable for reduced hydrogen darkening over long time periods. The optical fibers of the hybrid electro-optical cable may be single-mode fibers or multimode fibers for distributed temperature sensing, distributed strain sensing, or distributed acoustic sensing. The delay time for hydrogen may be due to diffusion transit time through the hydrogen-delay barrier and hydrogen traps related to hydrogen solubility within the barrier material. Once the hydrogen-delay barrier is fully saturated with hydrogen or internal hydride formation sites are exhausted, excess hydrogen may eventually break through across the hydrogen-delay barrier with a flux rate dependent on surface area, differential partial pressure of hydrogen, and diffusivity at temperature. As a result of the hydrogen-delay barrier, measurements of the hybrid electro-optical cable may have increased operational lifetimes, measurement reliability, and accuracy over long time periods. 
     Illustrative examples are given to introduce the reader to the general subject matter discussed herein and are not intended to limit the scope of the disclosed concepts. The following sections describe various additional features and examples with reference to the drawings in which like numerals indicate like elements, and directional descriptions are used to describe the illustrative aspects, but, like the illustrative aspects, should not be used to limit the present disclosure. 
       FIG. 1  is a cross-sectional view of an example of a well system  100  that includes a hybrid electro-optical cable  110  according to one example of the present disclosure. In the example shown in  FIG. 1 , the well system  100  includes a wellbore  102  extending through a hydrocarbon bearing subterranean formation  104 . A casing string  106  extends from the well surface  108  into the subterranean formation  104 . The casing string  106  can provide a conduit via which formation fluids, such as production fluids produced from the subterranean formation  104 , can travel from the wellbore  102  to the well surface  108 . 
     The well system  100  can also include a well tool  114  (e.g., a formation testing tool, a logging while drilling tool, or a reservoir monitoring tool). In some examples, the well tool  114  can include a fluid monitoring tool, a cement monitoring tool, a multi-phase flow monitoring system, a valve, a gauge, a sensor (e.g., a sensor for detecting pressure, strain, temperature, fluid density, fluid viscosity, acoustic vibrations, a chemical, an electric field, a magnetic field, or another parameter), an optical device or system, or any combination of these. The well tool  114  can be positioned in the wellbore  102  via the hybrid electro-optical cable  110 . For example, the well tool  114  can be lowered into the wellbore  102  by manipulating a winch  112  or pulley, unreeling the hybrid electro-optical cable  110  from a spool, or both. The hybrid electro-optical cable  110  may be fed through a wellhead exit or feedthrough packers. In some examples, the hybrid electro-optical cable  110  can also be extracted or removed from the wellbore  102  (e.g., to remove the well tool  114  from the wellbore  102 ). 
     In some examples, the hybrid electro-optical cable  110  can include a tube, such as a stainless steel tube or a polymer tube, which includes one or more optical fibers. The one or more optical fibers can include an enhanced backscatter fiber and a combination of single-mode fibers and multimode fibers. The tube can be coated in a material with a low hydrogen diffusivity and solubility that acts as a hydrogen-permeation delay barrier. The optical fibers can be used for communicating data between an optical device  118  (e.g., at the well surface  108  or elsewhere in the well system  100 ) and the well tool  114 . For example, the optical device  118  can transmit data encoded in optical signals to another optical device  116  positioned in the well tool  114  via the hybrid electro-optical cable  110 . The optical device  116  of the well tool  114  can receive the optical signals and determine the data from the optical signals. As another example, the well tool  114  can transmit data encoded in optical signals to the optical device  118  via the hybrid electro-optical cable  110 . The optical device  118  can receive the optical signals and determine the data from the optical signals. In this manner, two-way communication between the optical devices  116  and  118  can be achieved. The hybrid electro-optical cable  110  may be used to communicate distributed acoustic sensing measurements, distributed strain sensing measurements, or distributed temperature sensing measurements between the optical devices  116  and  118 . 
       FIG. 2  is a cross-sectional schematic of an example of a hybrid electro-optical cable  206  with insulated conductors and an optical fiber within a tube having a hydrogen-delay barrier according to some aspects of the present disclosure. The hybrid electro-optical cable  206  can be deployed downhole in a wellbore for transmitting data from downhole to an optical device. The hybrid electro-optical cable  206  can include a tube  200  in which one or more optical fibers  205  and one or more insulated conductors  202  are positioned. The tube  200  may be a fiber-in-metal-tube or a polymer tube. The optical fibers  205  can transmit optical signals between one or more optical devices, and the insulated conductors  202  can transmit electricity between surface equipment and a well tool. The optical fibers  205  and insulated conductors  202  may be parallel to each other or twisted helically. 
     In some examples, the optical fibers  205  may include a Verrillon carbon mid-temp acrylate 50/125 VHM2000 multimode fiber, a Verrillon carbon mid-temp acrylate VHS-100 single mode fiber, a high sensitivity single-mode OFS AcoustiSense fiber, which may increase optical signal-to-noise ratio. At least one of the optical fibers  205  can be an enhanced backscatter fiber that provides above Rayleigh-limited backscattering. The enhanced backscatter fiber can be manufactured to yield 10 to 20 dB optical signal-to-noise ratio (OSNR) gain over native Rayleigh-limited backscatter OSNRs. This may provide improved signal-to-noise ratios in distributed acoustic sensing signals, such as 4D vertical seismic profile imaging. Gains outside of the 10 to 20 dB signal-to-noise ratio range may also be possible. In some examples, the enhanced backscatter fiber can have weak continuous internal reflective optical gratings. In alternative examples, the enhanced backscatter fiber may be formed by discrete periodic internal fiber Bragg gratings at fixed distances along the sensing fiber. Enhanced backscatter may be gauge-length independent of the distributed acoustic sensing measurement in a case of periodic discontinuous internal gratings. 
     The enhanced backscatter fiber may not be carbon coated, or may be partially carbon coated. A partial carbon coating may be achieved by using a carbon-coated fiber as the base fiber, and damaging or perforating the carbon coating during ultraviolet or laser inscription of the weak gratings or discrete fiber Bragg gratings to photolithographically write or inscribe the reflective grating features deep within the core of the fiber. The enhanced backscatter fiber may additionally be processed prior to installation into the cable for improved hydrogen performance. For example, the enhanced backscatter fiber may be exposed to deuterium (heavy hydrogen with an additional neutron) over a period of time to allow the deuterium to permeate into the fiber to shift attenuation bands towards longer unused optical wavelengths. 
     In some examples, the insulated conductors  202  can be 18 AWG solid bare copper with black or white fluorinated ethylene propylene insulation. The tube  200  can include a hydrogen scavenging gel  201 , which may prevent internal annular hydrogen near the fiber(s) from reaching the surface of the optical fibers  205  by preferentially absorbing and reacting with free hydrogen. The hydrogen scavenging gel  201  may be Sepigel. 
     In some examples, the hybrid electro-optical cable  206  can include a hydrogen-delay barrier  204  external to the tube  200  and the insulated conductors  202 . The hydrogen-delay barrier  204  can be provided to reduce an amount and rate of hydrogen infill flux that can reach and react with the optical fibers  205 . The hydrogen-delay barrier  204  may be metallurgical and include fabrication via molten metal bath, an aluminum extrusion, an aluminum tube, a copper tube, a carbon-composite tube or any combination thereof. 
     The hybrid electro-optical cable  206  can also include an outer tube  207  that can encapsulate the hydrogen-delay barrier  204 . The outer tube  207  may be an 825 Alloy Sheath Tube per ASTM B704 and UNS N08825 with a wall thickness of 0.89 mm (0.035″) and an outer diameter of 6.35 mm (0.25″). The outer tube  207  may further be encapsulated by a thermoplastic, such as round Santoprene, for example. The hybrid electro-optical cable  206  may be spliced, such that there is electrical and optical continuity across the splice. The hybrid electro-optical cable  206  may also be in a wireline cable configuration. 
       FIG. 3  is a cross-sectional schematic of an example of a hybrid electro-optical cable  311  with a concentric-insulated conductor and tube with a hydrogen-delay barrier according to some aspects of the present disclosure. In some examples, a concentric-insulated conductor may include a conductor layer encapsulated by one or more insulator layers. The conductor layer and insulator layers may be oriented such that the conductor layer and insulator layers are concentric to each other. 
     In some examples, the hybrid electro-optical cable  311  can include a tube  305  encapsulating one or more optical fibers  300  for communicating optical signals. The optical fibers  300  may include a Verrillon carbon mid-temp acrylate 50/125 VHM2000, a Verrillon carbon mid-temp acrylate VHS-100 single mode fiber, an OFS AcoustiSense fiber, which may be a high sensitivity high OSNR single mode fiber. At least one of the optical fibers  300  can be an enhanced backscatter fiber. The hybrid electro-optical cable  311  can include a hydrogen scavenging gel  302  encapsulated by the tube  305  surrounding the optical fibers  300  which may prevent internal annular hydrogen near the fiber(s) from reaching the surface of the optical fibers  300  by preferentially absorbing and reacting with free hydrogen. The hydrogen scavenging gel  302  may be Sepigel. 
     In some examples, the hybrid electro-optical cable  311  can include a hydrogen-delay barrier  304  that encapsulates and is concentric with the tube  305 . The hydrogen-delay barrier  304  may reduce an amount of hydrogen that reacts with the optical fibers  300 . The hydrogen-delay barrier  304  may be metallurgical and include fabrication via molten metal bath, an aluminum extrusion, an aluminum tube, a copper tube, a carbon-composite tube or any combination thereof. The hybrid electro-optical cable may also include a conductor  306  coupled with an insulator  308  to form a concentric-insulated conductor. The conductor  306  may be concentric with the insulator  308 . The insulated conductor may be encapsulated by and concentric with an outer tube  310  for protection. In this example, the insulator  308  and conductor  306  may be concentric with the tube  305  containing the one or more optical fibers  300 , and the hydrogen-delay barrier  304 , and the outer tube  310 . The tube  305  can be encapsulated by the concentric-insulated conductor, which can be encapsulated by the outer tube  310 . 
       FIG. 4  is a cross-sectional schematic of another example of a hybrid electro-optical cable  400  with insulated conductors and an optical fiber  416  within a tube having a hydrogen-delay barrier according to some aspects of the present disclosure. 
     In some examples, the hybrid electro-optical cable  400  can include a tube  412  encapsulating one or more optical fibers  416 . The tube  412  can further encapsulate a hydrogen scavenging gel  414 , which may prevent internal annular hydrogen near the fiber(s) from reaching the surface of the optical fibers  416  by preferentially absorbing and reacting with free hydrogen. The hydrogen scavenging gel  414  may be Sepigel. The optical fibers  416  may include a Verrillon carbon mid-temp acrylate 50/125 VHM2000 multimode fiber, a Verrillon carbon mid-temp acrylate VHS-100 single mode fiber, a high sensitivity single-mode OFS AcoustiSense fiber, which may increase optical signal-to-noise ratio. The optical fibers  416  may not have a full carbon coating. The tube  412  containing the optical fibers  416  and hydrogen scavenging gel  414  can be encapsulated by a hydrogen-delay barrier  418  with a low hydrogen diffusivity to reduce hydrogen darkening. 
     The hybrid electro-optical cable  400  can also include insulated conductors  408 . The insulated conductors  408  can be 18 AWG solid bare copper with fluorinated ethylene propylene insulation. The outer diameter of the tube  412  with the hydrogen-delay barrier  418  can be the same outer diameter as the insulated conductors  408 . For example, the outer diameter of the tube  412  with the hydrogen-delay barrier  418  and the insulated conductors  408  can be 1.8 mm (0.070″). The hybrid electro-optical cable  400  may have a central strength member  410 . For example, the central strength member  410  can be an epoxy fiberglass rod used to twist the tube  412  and at least one of the insulated conductors  408  together. 
     In some examples, the insulated conductors  408  and tube  412  can be further encapsulated into a fiber belt  406 , such as fluorinated ethylene propylene. The fiber belt  406  can be encapsulated into an outer tube  404 . For example, the outer tube  404  can be an 825 Alloy Sheath Tube with a wall thickness of 0.89 mm (0.035″) and an outer diameter of 6.35 mm (0.25″). As another example, the outer tube  404  may be a ¼″ control line made of Iconel A825 or stainless steel. In some examples, the hydrogen-delay barrier  418  may additionally or alternatively be applied between twisted cables of the tube  412  and the outer tube  404 . The hybrid electro-optical cable  400  can further include an encapsulation  402  around the outer tube  404  that encapsulates the fiber belt  406 . The encapsulation  402  can be a thermoplastic, such as round Santoprene, with an outer diameter of 11.0 mm (0.433″), for example. 
       FIG. 5  is a cross-sectional schematic of an example of a hybrid electro-optical cable  512  with multiple concentrically arranged concentric-insulated conductors and a tube with a hydrogen-delay barrier according to some aspects of the present disclosure. 
     In this example, the hybrid electro-optical cable  512  can include one or more optical fibers  500  for communicating optical signals. The one or more optical fibers  500  may include a Verrillon carbon mid-temp acrylate 50/125 VHM2000 multimode fiber, a Verrillon carbon mid-temp acrylate VHS-100 single mode fiber, a high sensitivity single-mode OFS AcoustiSense fiber, which may have an increased optical signal-to-noise ratio. The hybrid electro-optical cable  512  may be spliced, such that there is electrical and optical continuity across the splice. The hybrid electro-optical cable  512  may also be in a wireline configuration. The hybrid electro-optical cable  512  can include a hydrogen scavenging gel  501 , which may prevent hydrogen from reacting with the optical fibers  500  by reacting preferentially with hydrogen. 
     The one or more optical fibers  500  and the hydrogen scavenging gel  501  may be encapsulated by a tube  502 , which may be further encapsulated by a hydrogen-delay barrier  504 . The hydrogen-delay barrier  504  may reduce the amount of hydrogen that permeates into the tube  502 , thereby reducing the amount of hydrogen that reacts with the optical fibers  500 . The hydrogen-delay barrier  504  may be metallurgical and include fabrication via molten metal bath, an aluminum extrusion, an aluminum tube, a copper tube, a carbon-composite tube or any combination thereof. The hybrid electro-optical cable  512  may also include a first conductor layer  506 . The first conductor layer  506  may encapsulate the hydrogen-delay barrier  504 . The first conductor layer  506  may be a tape made of a metal, such as copper. The first conductor layer  506  may be encapsulated by a first insulation layer  508  to form a concentric-insulated conductor. 
     In some examples, the first insulation layer  508  may be encapsulated by a second conductor layer  509 . The second conductor layer  509  may be insulated on its inner diameter by the first insulation layer  508 . The second conductor layer  509  may further insulated on its outer diameter by a second insulation layer  510 . The second conductor layer  509  may be a tape made of a metal, such as copper. The second insulation layer  510  may be encapsulated by an outer tube  511  for protection. The outer tube  511  may be a ¼″ control line made of Iconel A825 or stainless steel, which may further by encapsulated by a thermoplastic such as Santoprene. 
       FIG. 6  is a cross-sectional schematic of an example of a wireline-configured hybrid electro-optical cable  614  with a hydrogen-delay barrier for reducing hydrogen darkening according to some aspects of the present disclosure. 
     The hybrid electro-optical cable  614  can include a tube  604  including one or more optical fibers  600  for communicating optical signals. The tube  604  may be encapsulated by a hydrogen-delay barrier  606  that may reduce an amount of hydrogen that reacts with the optical fibers  600 . The hydrogen-delay barrier  606  may be metallurgical and include fabrication via molten metal bath, an aluminum extrusion, an aluminum tube, a copper tube, a carbon-composite tube or any combination thereof. The hybrid electro-optical cable  614  may also include one or more insulated conductors  602 , which may be used for conducting electricity between surface equipment and a well tool. The one or more insulated conductors  602  and the tube  604  can be encapsulated into an outer tube  610 , which, in a wireline configuration, can be further encapsulated by armor  612 . The armor  612  may be made of interlocked steel, interlocked aluminum, or welded aluminum. 
       FIG. 7  is a flowchart of a process for using a hybrid electro-optical cable to transmit data during a wellbore operation. The hybrid electro-optical cable may be any of the hybrid electro-optical cables described in  FIGS. 2-6 . 
     In block  702 , data is transmitted, through a hybrid electro-optical cable, from a first optical device to a second optical device positionable in a well tool. The hybrid electro-optical cable can include a tube including one or more optical fibers for communicating optical signals. The hybrid electro-optical cable can include a hydrogen-delay barrier that may reduce an amount of hydrogen that reacts with the optical fibers. The hydrogen-delay barrier may be metallurgical and include a molten metal bath, an aluminum extrusion, an aluminum tube, a copper tube, or any combination thereof. The hybrid electro-optical cable may also include an insulated conductor capable of conducting electricity. The tube and the one or more insulated conductors can be encapsulated into an outer tube, which can be further encapsulated by a thermoplastic encapsulation. The tube may also include a hydrogen scavenging gel which may prevent internal annular hydrogen near the fiber(s) from reaching the surface of said optical fibers by preferentially absorbing and reacting with free hydrogen. The hydrogen scavenging gel may be Sepigel. The hybrid electro-optical cable may include an enhanced backscatter fiber, which may be capable of above-Rayleigh backscattering. The data may be passed through the hybrid electro-optical cable as one or more optical signals. The data may be encoded in the optical signals via intensity modulation, frequency modulation, or optical phase modulation. The data may be used for distributed acoustic sensing, distributed strain sensing, or distributed temperature sensing. 
     In block  704 , a measurement is determined for a wellbore operation based on the data. The measurement may be used in vertical seismic profiling or reservoir diagnostics. The measurement may be determined with a photodiode or other light-detecting apparatus. The first or second optical device can receive the optical signals from the hybrid electro-optical cable and determine the measurement based on the optical signals. For example, strain measurements, temperature measurements, or other downhole measurements may be determined by the first or second optical device. The measurements may be used to adjust the wellbore operation. For example, drilling or production parameters may be adjusted based on the measurements. 
     In some aspects, systems and methods for a hybrid electro-optical cable having a hydrogen-delay barrier are provided according to one or more of the following examples: 
     Example 1 is a system comprising a tube comprising one or more optical fibers, a hydrogen-delay barrier encapsulating the tube, an insulated conductor, and an outer tube encapsulating the hydrogen-delay barrier and the insulated conductor. 
     Example 2 is the system of example 1, wherein the hydrogen-delay barrier is positionable between the tube and the outer tube, and the system further comprises a thermoplastic encapsulation encapsulating the outer tube. 
     Example 3 is the system of example 1, further comprising: a hydrogen scavenging gel within the tube and encapsulating the one or more optical fibers for reducing a hydrogen-darkening effect. 
     Example 4 is the system of example 1, wherein the insulated conductor is positionable external to the tube and is configured to have a same outer diameter as the tube with the hydrogen-delay barrier. 
     Example 5 is the system of example 1, wherein the tube is configured to be twisted with the insulated conductor within the outer tube. 
     Example 6 is the system of example 1, wherein at least one of the one or more optical fibers is an enhanced backscatter fiber for providing above-Rayleigh backscattering. 
     Example 7 is the system of example 1, wherein the insulated conductor is a concentric-insulated conductor comprising a conductor layer and one or more insulator layers, and the insulated conductor is configured to encapsulate and be concentric with the tube. 
     Example 8 is the system of example 1, wherein the hydrogen-delay barrier comprises a molten metal bath, an aluminum extrusion, an aluminum tube, or a copper tube. 
     Example 9 is a method comprising: transmitting, through a hybrid electro-optical cable, data from a first optical device to a second optical device positionable in a well tool, the hybrid electro-optical cable comprising: a tube comprising one or more optical fibers, a hydrogen-delay barrier encapsulating the tube, an insulated conductor, and an outer tube encapsulating the hydrogen-delay barrier and the insulated conductor, and determining a measurement for a wellbore operation based on the data. 
     Example 10 is the method of example 9, wherein the hydrogen-delay barrier is positionable between the tube and the outer tube, the hybrid electro-optical cable further comprising a thermoplastic encapsulation that encapsulates the outer tube. 
     Example 11 is the method of example 9, wherein a hydrogen scavenging gel within the tube encapsulates the one or more optical fibers for reducing a hydrogen-darkening effect. 
     Example 12 is the method of example 9, wherein the hydrogen-delay barrier comprises a molten metal bath, an aluminum extrusion, an aluminum tube, or a copper tube. 
     Example 13 is the method of example 9, wherein at least one of the one or more optical fibers is an enhanced backscatter fiber for providing above-Rayleigh backscattering. 
     Example 14 is the method of example 9, wherein the insulated conductor is a concentric-insulated conductor comprising a conductor layer and one or more insulator layers, the insulated conductor being configured to encapsulate and be concentric with the tube. 
     Example 15 is the method of example 9, wherein the insulated conductor is positionable external to the tube and is configured to have a same outer diameter of the tube with the hydrogen-delay. 
     Example 16 is a system comprising: a tool for performing a wellbore operation, and a cable communicatively coupled to the tool for providing communication for the tool, wherein the cable includes a hydrogen-delay barrier encapsulating a tube that includes one or more optical fibers. 
     Example 17 is the system of example 16, wherein the cable further includes: an outer tube configured to encapsulate the hydrogen-delay barrier, an insulated conductor positionable between the tube and the outer tube, and a thermoplastic encapsulation configured to encapsulate the outer tube. 
     Example 18 is the system of example 16, further comprising: a hydrogen scavenging gel within the tube encapsulating the one or more optical fibers for reducing a hydrogen darkening effect. 
     Example 19 is the system of example 17, wherein the tube is configured to be twisted with the insulated conductor within the outer tube. 
     Example 20 is the system of example 16, wherein at least one of the one or more optical fibers is an enhanced backscatter fiber for providing above-Rayleigh backscattering. 
     The foregoing description of certain examples, including illustrated examples, has been presented only for the purpose of illustration and description and is not intended to be exhaustive or to limit the disclosure to the precise forms disclosed. Numerous modifications, adaptations, and uses thereof will be apparent to those skilled in the art without departing from the scope of the disclosure.