Patent Description:
Aspects of the present disclosure generally relate to an armored cable having one or more optical fibers contained therein. More particularly, aspects of the present disclosure relate to a fiber optic cable having an armored tube and one or more optical fibers adhered to an inner wall of the armored tube and techniques for fabricating such a cable.

In the last few decades, the deployment of optical fibers has exploded, not only for the transmission of information, but also for measuring various physical parameters. By its intrinsic nature, the optical fiber can serve as a distributed sensor through its scattering characteristics. For example, Rayleigh scattering has been used for monitoring optical power along the fiber path, Raman scattering has been used to measure the temperature profile along the fiber, and Brillouin scattering has been used to measure the fiber strain profile. In addition, an optical fiber's local optical properties can be modified to reflect signals dependent on local physical parameters. For example, fiber Bragg gratings (FBGs) reflect optical signals centered at varying wavelengths according to the local fiber temperature and/or strain.

In the last couple of decades, optical fibers have been increasingly used to monitor oil and gas wells. The small diameter and long reach of fibers are ideal for insertion in such wells and do not obstruct the wells significantly to alter their primary function as fluid conduits. In addition, since optical fibers are made of glass, the fibers may remain inert even in the high temperature and pressure conditions downhole, which are too harsh for most materials. One drawback of optical fibers is their fragility against mechanical scratching and crushing; consequently, optical fibers are typically embedded in a mechanically protective layer to form an optical fiber cable. Tubes composed of corrosion-resistant alloys are the mechanical protective layer generally used in oil and gas wells, for optical fibers transmitting optical signals between the surface and individual point optical sensors downhole.

<CIT> teaches techniques and corresponding apparatus for making armored cables with optical fibers contained therein. The techniques may be utilized to control an amount of excess fiber length (EFL) in the armored cables. The techniques may also allow introduction of optical fibers directly into a welding process without using an inner tube in the final armored cable.

<CIT> teaches a means for producing an optical fibre cable. At least one fibre is introduced into a metal tube which has grooves extending with axial spacings in the circumferential direction. The fibre, which is bonded at least in punctiform fashion to the metal tube, extends in an undulating fashion.

Certain aspects of the present disclosure provide a method for making an armored cable as defined in claim <NUM>.

So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

Certain aspects of the present disclosure provide armored fiber optic cables having an armor tube and one or more optical fibers attached to an inner wall of the armor tube, as well as techniques for making these cables. Such fiber optic cables may be capable of deployment in oil and gas wells, for example, for monitoring of the wells.

Downhole optical fiber cables may be manufactured using an outer armor tubing for protection of one or more optical fibers and/or wires contained therein. To form the armor tubing, flat tube strip stock may be fed to a tube-forming stage, which gradually rolls up the sides of the tube strip stock into a tube as the tube strip stock moves through the process at a particular feed rate. The seam in the nearly completed tube is then welded in a welding zone to form a seam-welded armor tubing. After welding, the armor tubing may be further formed with rollers or a sizing die, for example, to produce a desired finished diameter for the armor tubing (e.g., ¼" diameter).

Protection of the optical fibers and/or wires from the armor tubing welding process may be provided by using guide tubes. The guide tubes may be fixed in position in the welding zone, at or near the welding point. The guide tube's fiber or wire entrance (i.e., inlet) may be located (just) before or in the armor tube's tube-forming stage. The guide tube's fiber or wire exit (i.e., outlet) may be disposed inside the welded armor tube, beyond a point at which heat from welding would damage the fibers and/or wires and, in some cases, beyond the final size-forming process of the tube.

It is often desirable to have some amount of excess fiber length (EFL) in the armored cable, for example, to reduce strain on the optical fibers. EFL generally refers to an excess length of the fiber relative to the armor tubing. The amount of EFL in the finished armored cable may be controlled by the ratio of the fiber pushing speed to the armor tubing welding line speed (e.g., the ratio of these feed rates generally determines the amount of EFL). The optical fiber may be pushed through the guide tube with a fiber feed device, which is a mechanism that can feed the fiber from a fiber source at a controlled rate. The EFL can then be managed by controlling the fiber's feed rate as compared to the armor tubing welding line speed (i.e., the tube rate). In some cases, the optical fiber(s) may be put into an armor tubing after the armor tubing is manufactured by pushing fiber into the armor tubing with the aid of gas or liquids.

<FIG> illustrates fabrication of an armored cable, in accordance with previously known techniques. The armored cable comprises an armor tubing <NUM> and one or more optical fibers and/or wires <NUM> (only one optical fiber or wire is illustrated in <FIG> for simplicity). To form the armor tubing <NUM>, flat tube strip stock at <NUM> may be fed to a tube-forming stage <NUM>, which gradually rolls up the sides of the tube strip stock into a tube as the tube strip stock moves through the process at a particular tube rate. The seam (which may be a <NUM>/<NUM> in. seam) in the nearly completed tube is then welded in the welding zone <NUM> by a welder <NUM> (e.g., an arc welder or a welding torch) to form a completed, seam-welded armor tubing.

Protection of the fibers and/or wires <NUM> from the armor tubing welding process may be provided by using guide tubes <NUM>. The guide tubes <NUM> may be made of metal, ceramic, or any of various other suitable heat-resistant materials. The guide tubes <NUM> may be fixed in position in the welding zone <NUM>, at or near the welding point. The guide tube's fiber entrance (i.e., inlet) <NUM> may be located (just) before or in the armor tubing's tube forming stage <NUM>. The guide tube's exit <NUM> (i.e., outlet) may be disposed inside the welded armor tubing, beyond a point at which heat from welding would damage the fibers.

The amount of EFL in the finished armored cable may be controlled by the ratio of the fiber pushing speed to the armor tubing welding line speed (e.g., the ratio of these feed rates generally determines the amount of EFL). The fiber is pushed through the guide tube <NUM> with a fiber feed device <NUM>, a mechanism that can feed the fiber from a fiber source <NUM> at a controlled rate. The EFL can then be managed by controlling the fiber's feed rate as compared to the armor tubing welding line speed (i.e., the tube rate).

<FIG> illustrates an example conventional fiber optic cable <NUM> design. The example conventional fiber optic cable <NUM> has a small-diameter inner tube <NUM> that may contain optical fibers and/or wires <NUM>, <NUM>, and <NUM> along with a gel material <NUM>. The nature of the small-diameter tube and gel prevents the optical fibers and/or wires from shifting. The small-diameter tube is surrounded by a buffer material <NUM> to hold the small-diameter tube centralized within the outer armor tube <NUM>. This design containing an inner tube and buffer is typical of previous designs. To isolate fiber Bragg gratings (FBGs) within a cable, elaborate and costly methods of construction have been developed that include cutting the cable to insert FBGs and then splicing the cable segments together.

In order to reduce the cost of optical fiber cables used for downhole oil and gas sensing, cables may be manufactured with minimal components. Some cable designs include only an outer armor tube with optical fibers enclosed (e.g., small diameter fibers having a cladding with a typical diameter of <NUM>). The optical fibers, if not supported, may shift axially within the armor tube, especially when the tube is vertical. The optical fiber may then be compressed in areas, causing optical loss and possible fracture failure from bending. Another problem that may be created by an axial shift of the optical fiber is an inability to isolate FBGs from strain within the cable, despite the presence of EFL in the cable.

Certain aspects of the present disclosure provide an armored cable having one or more optical fibers and/or wires adhered to an inner wall of the armored cable. The armored cable having one or more optical fibers and/or wires adhered to an inner wall of the armored cable may help overcome difficulties caused by optical fibers and/or wires shifting longitudinally, due to the weight of the optical fibers and/or wires when the armored cable is deployed downhole.

<FIG> is a cross-sectional view of an example fiber optic cable <NUM> with an adhesive material <NUM> attached to an inner wall of the armor tubing, according to certain aspects of the present disclosure. In the fiber optic cable <NUM>, an armor tubing <NUM> may have one or more optical fibers and/or wires <NUM> attached to an inner wall <NUM> of the armor tubing <NUM>.

According to aspects of the present disclosure, the armor tubing <NUM> may be composed of a metal.

According to the claims, one or more strips of adhesive material <NUM> are used to attach the one or more optical fibers and/or wires <NUM> to the inner wall <NUM> of the armor tubing <NUM>. The adhesive material <NUM> may be applied within the armor tubing <NUM> either j, in an example not according to the claims, just beyond where the armor tubing is welded or, according to the claims, on the tube strip stock before or during the tube-forming and welding process. The optical fibers and/or wires may or may not be continuously adhered to the inner wall of the armor tubing. For example, if an armored cable includes EFL, then the optical fibers will be fed into the tubing at a faster rate than the armor tubing is moving through the welding line, possibly resulting in the optical fibers randomly, periodically, or intermittently contacting the adhesive material.

The adhesive material <NUM> may comprise, for example, a sticky, tacky, or gel-like substance, such as silicone, or any of various other suitable materials for attaching an optical fiber or wire to an inner wall <NUM> of the armor tubing <NUM>. The adhesive material may not necessarily create a permanent bond with the inner wall <NUM>, but may allow the optical fiber(s) and/or wire(s) to release if a force greater than the weight of the fiber(s) and/or wire(s) is applied.

According to aspects of the present disclosure, each of the one or more strips of adhesive material <NUM> has a first side <NUM> and a second side <NUM>. As illustrated in <FIG>, the first side <NUM> may be attached to the inner wall <NUM> of the armor tubing <NUM>, and the second side <NUM> may be attached to one or more of the optical fibers and/or wires <NUM>. For other aspects, the adhesive material may have a cross-section with more or less than four sides. That is, the adhesive material may have, for example, a triangular cross-section or a hexagonal cross-section. For certain aspects, the adhesive material may have no discernable sides. For example, the adhesive material may be circular or elliptical in cross-section or have a cross-section similar to a sector or segment of a circle (e.g., semicircular).

<FIG> illustrates fabrication of an armored cable, in accordance with certain aspects of the present disclosure. The fabrication and armored cable illustrated in <FIG> are similar to the fabrication and armored cable illustrated in <FIG>, and items previously described in the description of <FIG> are not further described. The armored cable comprises an armor tubing <NUM>, one or more optical fibers and/or wires <NUM> (only one optical fiber is illustrated in <FIG> for simplicity), and adhesive material <NUM>. The adhesive material <NUM> may be applied to the tube strip stock <NUM> by an adhesive applicator <NUM>. The adhesive material <NUM> may be implemented as a continuous strip, as illustrated. Alternatively, the adhesive material <NUM> may be implemented as a plurality of discontinuous strips or a plurality of discrete quantities (e.g., beads, droplets, or dollops). The exit <NUM> of the guide tube <NUM> may be configured to allow the optical fibers and/or wires <NUM> to contact the adhesive material <NUM> (e.g., via gravity) after the optical fibers or wires exit the guide tube. For certain aspects, the exit <NUM> of the guide tube <NUM> may be configured to direct the optical fibers and/or wires <NUM> toward the adhesive material <NUM> after the optical fibers or wires exit the guide tube.

<FIG> illustrates an example fiber optic cable <NUM> wherein at least one of the strips of adhesive may be a continuous strip <NUM> of adhesive material.

<FIG> illustrates an example fiber optic cable <NUM> wherein a plurality of strips <NUM>, <NUM>, <NUM>, and <NUM> of adhesive material are arranged intermittently within an armor tubing <NUM>, according to certain aspects of the present disclosure.

In aspects of the present disclosure, an intermittent strip of adhesive material may comprise a continuous strip having a plurality of adhesive sections interspersed with a plurality of sections that have no adhesive materials (e.g., blank sections with no material or non-adhesive material).

According to certain aspects of the present disclosure, one or more of the strips of adhesive material for attaching the one or more optical fibers and/or wires to the inner wall of the armor tube may be a hard-curing material. For certain aspects, the hard-curing material may be an epoxy.

In aspects of the present disclosure, the armor tubing has a central longitudinal axis, and the one or more optical fibers and/or wires are disposed radially away from the central longitudinal axis.

According to certain aspects of the present disclosure, no other tube is disposed in the armor tubing along the entire length of the fiber optic cable. For other aspects, no other tube is disposed in the armor tubing along at least a portion of the length of the fiber optic cable.

According to certain aspects of the present disclosure, a fluid may be disposed inside the armor tubing. In certain aspects, the fluid may be a gas. For example, the gas may be air or argon (e.g., introduced by the welding process). For other aspects, the fluid may be a gel. For example, the gel may include conventional thixotropic gels, grease compounds, and/or foams commonly used in the fiber optic cable industry for water blocking, hydrogen scavenging, and/or filling.

<FIG> is a cross-sectional view of fabrication of an example armored cable <NUM>, according to certain aspects of the present disclosure. The armored cable <NUM> is shown in a welding zone (e.g., welding zone <NUM>, shown in <FIG>) of a fabrication process. The armored cable <NUM> comprises armor tubing <NUM>, adhesive material <NUM>, and an optical fiber or wire <NUM>. Seam-welding of the armor tubing is represented at weld <NUM>. The optical fiber or wire <NUM> is protected (e.g., from heat associated with welding) by a guide tube <NUM>, which may be an example of the guide tube <NUM> (shown in <FIG>), in accordance with aspects of the present disclosure. According to the claims, the guide tube <NUM> is supported by a plurality of legs <NUM> so as to prevent the guide tube <NUM> from contacting the adhesive material <NUM>. The legs <NUM> are attached to the guide tube <NUM>, as described in more detail below with reference to <FIG>. The legs <NUM> may be curved or the ends (or end portions) of the legs may have a coating (e.g., a lubricant, such as graphite), to aid with sliding of the armor tubing and to prevent scratching or other damage to an inner surface of the armor tubing.

<FIG> illustrates an overhead view of an exemplary guide tube <NUM> and legs <NUM>, according to aspects of the present disclosure. As illustrated, each of the legs 610a-B and 610b-B includes a middle portion 660a-B or 660b-B that is attached (e.g., welded) to the guide tube <NUM> and an end portion 650a-B or 650b-B that may contact the armor tubing (see <FIG>) to support the guide tube <NUM> and prevent the guide tube <NUM> from contacting the adhesive material (see <FIG>). The legs <NUM> may optionally, as represented by the dashed lines, comprise a plurality of middle portions that are attached to the guide tube and other portions that contact the armor tubing.

<FIG> illustrates an overhead view of an exemplary guide tube <NUM> and legs <NUM>, according to aspects of the present disclosure. As illustrated, each of the legs 610a-C and 610b-C is formed from an end portion 650a-C or 650b-C that extends from a middle portion <NUM>-C that is wrapped around the guide tube <NUM>. This design may be similar to a hose clamp. The end portions 650a-C and 650b-C may contact the armor tubing (see <FIG>) to support the guide tube <NUM> and prevent the guide tube <NUM> from contacting the adhesive material (see <FIG>). The middle portion <NUM>-C may optionally be attached (e.g., welded or soldered) to the guide tube <NUM>. Optionally, as represented by the dashed lines, a plurality of legs <NUM> may support the guide tube <NUM> and contact the armor tubing.

<FIG> is a cross-sectional view of fabrication of an example armored cable <NUM>, according to certain aspects of the present disclosure. The armored cable <NUM> is shown in a welding zone (e.g., welding zone <NUM>, shown in <FIG>) of a fabrication process. The armored cable <NUM> comprises armor tubing <NUM>, adhesive material <NUM>, a first optical fiber or wire 602a, and a second optical fiber or wire 602b. Seam-welding of the armor tubing is represented by weld <NUM>. The optical fibers or wires <NUM> are protected (e.g., from heat associated with welding) by a first guide tube 708a and a second guide tube 708b, which may be examples of the guide tube <NUM> (shown in <FIG>), in accordance with aspects of the present disclosure. While the armored cable <NUM> is shown with two optical fibers or wires each protected by a guide tube, the present disclosure is not so limited, and additional optical fibers or wires may be protected by additional guide tubes. For other aspects, each guide tube may include more than one optical fiber or wire. According to the claims, the first guide tube 708a is supported by a plurality of legs <NUM> so as to prevent the guide tube 708a from contacting the adhesive material <NUM>. The legs <NUM> are attached to the guide tube 708a, as described in more detail above with reference to <FIG>. The second guide tube 708b may be attached (e.g., welded) to the first guide tube 708a, such that the second guide tube 708b is supported by the first guide tube 708a and prevented from contacting the adhesive material <NUM>.

<FIG> is a cross-sectional view of fabrication of an example armored cable <NUM>, according to certain aspects of the present disclosure. The armored cable <NUM> is shown in a welding zone (e.g., welding zone <NUM>, shown in <FIG>) of a fabrication process. The armored cable <NUM> comprises armor tubing <NUM>, adhesive material <NUM>, a first optical fiber or wire 602a, and a second optical fiber or wire 602b. Seam-welding of the armor tubing is represented by weld <NUM>. The optical fibers or wires <NUM> are protected (e.g., from heat associated with welding) by a first guide tube 758a and a second guide tube 758b, which may be examples of the guide tube <NUM> (shown in <FIG>), in accordance with aspects of the present disclosure. While the armored cable <NUM> is shown with two optical fibers or wires each protected by a guide tube, the present disclosure is not so limited, and additional optical fibers or wires may be protected by additional guide tubes. For other aspects, each guide tube may include more than one optical fiber or wire. According to the claims, the first guide tube 758a is supported by a plurality of legs <NUM> so as to prevent the guide tube 758a from contacting the adhesive material <NUM>. The legs <NUM> are attached to the guide tube 758a, as described in more detail above with reference to <FIG>. The second guide tube 758b may also be supported by a plurality of legs <NUM> so as to prevent the guide tube 758a from contacting the adhesive material <NUM>. The legs <NUM> may be attached to the guide tube 758b, as described in more detail above with reference to <FIG>. For certain aspects, the legs <NUM> may be located at a different axial position than the legs <NUM> (i.e., legs <NUM> are offset from legs <NUM>).

<FIG> illustrates fabrication of an armored cable. The fabrication and armored cable illustrated in <FIG> are similar to the fabrication and armored cable illustrated in <FIG>, and items previously described in the description of <FIG> are not further described. The armored cable comprises an armor tubing <NUM>, one or more optical fibers and/or wires <NUM> (only one optical fiber or wire is illustrated in <FIG> for simplicity), and adhesive material <NUM>. The adhesive material <NUM> may be a mixture of a first material and a second material (e.g., two different materials). The first material may be supplied from a source <NUM> via a first injection tube <NUM> that extends through the welding zone <NUM>. Similarly, the second material may be supplied from a source <NUM> via a second injection tube <NUM> that extends through the welding zone <NUM>. The first material and the second material may be mixed after passing through the welding zone, and the mixture may be applied to an inner surface of the armor tubing <NUM>. The adhesive material <NUM> (i.e., the mixture) may be a continuously applied liquid or gel, as illustrated. Alternatively, the adhesive material <NUM> may be applied as a plurality of discrete quantities (e.g., beads, droplets, or dollops) of the mixture. The first material and the second material may be optionally mixed in a static mixer <NUM>, which may be attached to the first injection tube <NUM> and the second injection tube <NUM>. The exit(s) <NUM> of the guide tube(s) may be configured to allow the optical fibers and/or wires <NUM> to contact the mixture after the optical fibers and/or wires exit the guide tube(s). For certain aspects, the exit(s) <NUM> of the guide tube(s) may be configured to direct the optical fibers and/or wires <NUM> toward the mixture after the optical fibers and/or wires exit the guide tube(s).

<FIG> is a cross-sectional view of fabrication of an example armored cable <NUM>. The armored cable <NUM> is shown in a welding zone (e.g., welding zone <NUM>, shown in <FIG>) of a fabrication process. The armored cable <NUM> comprises armor tubing <NUM>, adhesive material <NUM> (not shown, see <FIG>), and a plurality of optical fibers and/or wires <NUM>. Seam- welding of the armor tubing is represented by weld <NUM>. The optical fibers and/or wires <NUM> are each protected (e.g., from heat associated with welding) by a guide tube <NUM>, which may be examples of the guide tube <NUM> (shown in <FIG>). As illustrated, injection tubes <NUM> and <NUM> extend through the welding zone adjacent to the guide tubes <NUM>. Although two guide tubes <NUM> are shown, the reader is to understand that more or fewer than two guide tubes may be used in the fabrication of the armored cable. In an example not according to the claims, the guide tubes <NUM> and injection tubes <NUM> and <NUM> may be supported and contained by an outer guide tube <NUM>. Alternatively, the outer guide tube <NUM> may not be present, and each of the guide tubes <NUM> and injection tubes <NUM> and <NUM> may be supported by the armor tubing <NUM>. Space <NUM> within the outer guide tube may optionally allow for introduction of an inert and/or cooling gas during the fabrication process.

<FIG> is a flow diagram of example operations <NUM> for making an armored cable, in accordance with aspects of the present disclosure. The operations <NUM> may begin, at block <NUM>, by applying an adhesive material to a strip stock.

At block <NUM>, operations <NUM> continue with forming the strip stock with the adhesive material into an armor tubing.

Operations <NUM> continue at block <NUM><NUM> with welding a seam of the armor tubing in a welding zone.

At block <NUM>, operations <NUM> continue with inserting at least one of a first optical fiber or a first wire into a first end of a first guide tube, wherein: the first guide tube extends through the welding zone; the first guide tube protects the at least one of the first optical fiber or the first wire during the welding of the seam; the at least one of the first optical fiber or the first wire contacts the adhesive material after exiting a second end of the first guide tube; and the first guide tube is not part of the armored cable after the making of the armored cable.

According to certain aspects of the present disclosure, applying the adhesive material at block <NUM> includes applying a strip of the adhesive material to the strip stock.

In certain aspects of the present disclosure, applying the adhesive material at block <NUM> includes applying discrete quantities of the adhesive material to the strip stock.

According to the claims, operations <NUM> further include supporting the first guide tube within the armor tubing such that the first guide tube does not contact the armor tubing. Supporting the first guide tube comprises preventing the first guide tube from contacting the adhesive material in certain aspects of the present disclosure. A second end of the first guide tube is supported by a plurality of support legs. A middle portion of a support wire is attached to the first guide tube and at least one end portion of the support wire is one of the plurality of support legs. A support wire may extend axially along the first guide tube, a plurality of first portions of the support wire may be attached to the first guide tube, and a plurality of second portions of the support wire may be spaced from the first guide tube and may each form one of the plurality of support legs, in certain aspects. According to certain aspects of the present disclosure, a middle portion of a support wire may be wrapped around the first guide tube and at least one end portion of the support wire may be one of the plurality of support legs.

In certain aspects of the present disclosure, not according to the claims, the first guide tube may be disposed within an outer guide tube. According to certain aspects of the present disclosure, operations <NUM> may further include introducing a gas within the outer guide tube.

According to certain aspects of the present disclosure, operations <NUM> may further include inserting at least one of a second optical fiber or a second wire into a first end of a second guide tube, wherein: the second guide tube extends through the welding zone; the second guide tube protects the at least one of the second optical fiber or the second wire during the welding; the at least one of the second optical fiber or the second wire contacts the adhesive material after exiting a second end of the second guide tube; and the second guide tube is not part of the armored cable after the making of the armored cable.

In certain aspects of the present disclosure, the adhesive material may adhere the at least one of the first optical fiber or the first wire to an interior surface of the armor tubing.

According to certain aspects of the present disclosure, the adhesive material may adhere a plurality of first portions of the at least one of the first optical fiber or the first wire to a plurality of locations on the interior surface of the armor tubing, and a plurality of second portions of the at least one of the first optical fiber or the first wire may not be adhered to the interior surface of the armor tubing.

<FIG> is a flow diagram of example operations <NUM> for making an armored cable, in accordance with aspects of the present disclosure. The operations <NUM> may begin, at <NUM>, by forming a strip stock into an armor tubing.

At block <NUM>, operations <NUM> continue with welding a seam of the armor tubing in a welding zone.

Operations <NUM> continue at block <NUM> with inserting at least one of a first optical fiber or a first wire into a first end of a first guide tube, wherein: the first guide tube extends through the welding zone; the first guide tube protects the at least one of the first optical fiber or the first wire during the welding of the seam; and the first guide tube is not part of the armored cable after the making of the armored cable.

At block <NUM>, operations <NUM> continue with supporting the first guide tube within the armor tubing by a plurality of support legs such that the first guide tube does not contact the armor tubing.

Operations <NUM> further include applying an adhesive material to an interior surface of the armor tubing, wherein the at least one of the first optical fiber or the first wire contacts the adhesive material after exiting a second end of the first guide tube. In aspects of the present disclosure, not according to the claims, applying the adhesive material may include applying the adhesive material to a welded portion of the armor tubing outside of the welding zone. In aspects of the present disclosure, supporting the first guide tube comprises preventing the first guide tube from contacting the adhesive material. According to aspects of the present disclosure, the operations may also include inserting at least one of a second optical fiber or a second wire into a first end of a second guide tube, wherein: the second guide tube extends through the welding zone; the second guide tube protects the at least one of the second optical fiber or the second wire during the welding; the at least one of the second optical fiber or the second wire contacts the adhesive material after exiting a second end of the second guide tube; and the second guide tube is not part of the armored cable after the making of the armored cable.

According to the claims, a middle portion of a support is attached to the first guide tube and at least one end portion of the support wire may be one of the plurality of support legs in operations <NUM>.

According to aspects of the present disclosure, a support wire may extend axially along the first guide tube, a plurality of first portions of the support wire may be attached to the first guide tube, and a plurality of second portions of the support wire may be spaced from the first guide tube and each form one of the plurality of support legs in operations <NUM>.

In aspects of the present disclosure, a middle portion of a support wire may be wrapped around the first guide tube and at least one end portion of the support wire may be one of the plurality of support legs in operations <NUM>.

According to aspects of the present disclosure, operations <NUM> may further include inserting at least one of a second optical fiber or a second wire into a first end of a second guide tube, wherein: the second guide tube is disposed in the welding zone; the second guide tube protects the at least one of the second optical fiber or the second wire during the welding; and the second guide tube is not part of the armored cable after the making of the armored cable.

<FIG> is a flow diagram of example operations <NUM>, not according to the claims, for making an armored cable. The operations <NUM> may begin, at block <NUM>, by forming a strip stock into an armor tubing.

At block <NUM>, operations <NUM> may continue with welding a seam of the armor tubing in a welding zone.

Operations <NUM> may continue at block <NUM> with applying an adhesive material to a welded portion of the armor tubing outside of the welding zone, wherein the adhesive material comprises a mixture of a first material and a second material and wherein applying the adhesive material to the armor tubing comprises: introducing the first material via a first injection tube that extends through the welding zone; introducing the second material via a second injection tube that extends through the welding zone; mixing the first material and the second material to form the mixture; and applying the mixture of the first material and the second material to an inner surface of the armor tubing.

At block <NUM>, operations <NUM> continue with inserting at least one of a first optical fiber or a first wire into a first end of a first guide tube, wherein: the first guide tube extends through the welding zone; the first guide tube protects the at least one of the first optical fiber or the first wire during the welding of the seam; the at least one of the first optical fiber or the first wire contacts the mixture after exiting a second end of the first guide tube; and the first guide tube is not part of the armored cable after the making of the armored cable.

The first injection tube may be secured to at least one of the first guide tube or the second injection tube in operations <NUM>.

The first injection tube, the second injection tube, and the first guide tube are disposed within an outer guide tube in operations <NUM>. Operations <NUM> may include introducing a gas within the outer guide tube.

Operations <NUM> may further include inserting at least one of a second optical fiber or a second wire into a first end of a second guide tube, wherein: the second guide tube extends through the welding zone; the second guide tube protects the at least one of the second optical fiber or the second wire during the welding; the at least one of the second optical fiber or the second wire contacts the mixture after exiting a second end of the second guide tube; and the second guide tube is not part of the armored cable after the making of the armored cable.

The mixing of block <NUM> may include introducing the first material and the second material into a static mixer.

Certain examples may be suitable for particular sensing applications, and in some cases, may provide for increased sensitivity compared to conventional fiber optic cables. For example, in acoustic sensing applications such as distributed acoustic sensing (DAS), since the optical fibers are attached to an inner wall of the armor tube, the fiber optic cable described herein may offer increased acoustic sensitivity compared to conventional fiber optic cables, where the acoustic signals have to pass through multiple layers of the cable before reaching the optical fibers. The proximity of the optical fibers to the armor tube may also increase sensitivity to thermal conditions external to the fiber optic cable.

It is understood that the specific order or hierarchy of steps in the processes disclosed above is an illustration of exemplary approaches. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged. Further, some steps may be combined or omitted. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented.

" For example, unless specified otherwise or clear from the context, the phrase "X employs A or B" is intended to mean any of the natural inclusive permutations.

Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean "one and only one" unless specifically so stated, but rather "one or more.

Claim 1:
A method for making an armored cable, comprising:
applying (<NUM>) an adhesive material (<NUM>, <NUM>, <NUM>) to a strip stock (<NUM>);
forming (<NUM>) the strip stock (<NUM>) with the adhesive material (<NUM>, <NUM>, <NUM>) into an armor tubing (<NUM>, <NUM>, <NUM>, <NUM>);
welding (<NUM>) a seam of the armor tubing (<NUM>, <NUM>, <NUM>, <NUM>) in a welding zone (<NUM>);
inserting (<NUM>) at least one of a first optical fiber or a first wire (<NUM>, <NUM>, <NUM>) into a first end (<NUM>) of a first guide tube (<NUM>, <NUM>); and,
supporting (<NUM>) a second end (<NUM>) of the first guide tube (<NUM>, <NUM>) within the armor tubing (<NUM>, <NUM>, <NUM>, <NUM>) with a plurality of support legs (610a, 610b) such that the first guide tube (<NUM>, <NUM>) does not contact the armor tubing (<NUM>, <NUM>, <NUM>, <NUM>), wherein a middle portion (660a, 660b) of a support wire (610a, 610b) is attached to the first guide tube (<NUM>, <NUM>), and wherein at least one end portion (650a, 650b) of the support wire is one of the plurality of support legs (610a, 610b),
wherein:
the first guide tube (<NUM>) extends through the welding zone (<NUM>);
the first guide tube (<NUM>) protects the at least one of the first optical fiber or the first wire (<NUM>, <NUM>, <NUM>) during the welding (<NUM>) of the seam;
the at least one of the first optical fiber or the first wire (<NUM>, <NUM>, <NUM>) contacts the adhesive material (<NUM>, <NUM>, <NUM>) after the at least one of the first optical fiber or the first wire (<NUM>, <NUM>, <NUM>) exits the second end (<NUM>) of the first guide tube (<NUM>, <NUM>); and
the first guide tube (<NUM>, <NUM>) is not part of the armored cable after the making of the armored cable.