Patent Description:
Piping systems, including municipal water systems, can develop breaks in pipe walls that can cause leaking. Example of breaks in a pipe wall can include radial cracks, axial cracks, point crack, etc. Repairing a break in a pipe wall often requires the piping system to be shut off, which can be inconvenient for customers and costly for providers. Further, repairs can necessitate grandiose construction, including the digging up of streets, sidewalks, and the like, which can be costly and time-consuming.

<CIT> discloses a repair sleeve comprising a flexible, hose-like main part and a spiral spring, which, when the sleeve is mounted in a pipe line, pretensions the hose-like main part into sealing engagement against the inner wall of the surrounding pipe.

<CIT> discloses a cylindrical body is provided whose sleeve is constructed as a cylindrical spring. Its external diameter in the unstressed state is greater than the internal diameter of the cylindrical surface. The two ends of the cylindrical spring can be rotated by a drive relative to one another, about the spring axis, such that the external diameter of the cylindrical spring with the drive switched on is reduced to a predetermined diameter which is smaller than the diameter of the cylindrical surface. By reversing the direction of rotation of the drive, the cylindrical spring is relieved of stress and presses against the cylindrical surface.

The features and components of the following figures are illustrated to emphasize the general principles of the present disclosure. Corresponding features and components throughout the figures may be designated by matching reference characters for the sake of consistency and clarity.

The present disclosure can be understood more readily by reference to the following detailed description, examples, drawings, and claims, and the previous and following description. However, before the present devices, systems, and/or methods are disclosed and described, it is to be understood that this disclosure is not limited to the specific devices, systems, and/or methods disclosed unless otherwise specified, and, as such, can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting.

Disclosed in the present application is a stent for repairing a pipe and associated methods, systems, devices, and various apparatus. Example aspects of the stent can comprise a spring and a sealing layer. It would be understood by one of skill in the art that the disclosed stent is described in but a few exemplary aspects among many. No particular terminology or description should be considered limiting on the disclosure or the scope of any claims issuing therefrom, whereas the invention is solely disclosed in the appended claims.

<FIG> illustrates a first aspect of a stent <NUM>, according to the present disclosure. The stent <NUM> can comprise a spring <NUM> and a sealing layer <NUM>. Example aspects of the stent <NUM> can be expandable and compressible, such that the stent <NUM> can be oriented in an expanded configuration <NUM>, as shown in <FIG>, and a compressed configuration <NUM>, as shown in <FIG>. (Note that in <FIG>, the sealing layer <NUM> is removed for visibility of the spring <NUM>. ) According to example aspects, the stent <NUM> can be expanded within a pipe <NUM> (shown in <FIG>) such that the sealing layer <NUM> can engage an inner wall <NUM> of the pipe <NUM>. In a pipe <NUM> where a crack <NUM> (shown in <FIG>) or other damage is present, the sealing layer <NUM> can create a watertight seal between the stent <NUM> and the inner surface of the pipe <NUM> at the location of the damage to prevent leaking at the damage site.

As shown in <FIG>, the spring <NUM> can bias the stent <NUM> to the expanded configuration <NUM>. In the depicted aspect, the spring <NUM> can be formed as a substantially tubular mesh structure <NUM> defining opposing open ends 112a,b. The spring <NUM> can further define an outer surface <NUM> (best seen in <FIG>) and an opposite inner surface <NUM>. The inner surface <NUM> can define an inner diameter of the spring <NUM> and the outer surface <NUM> can define an outer diameter of the spring <NUM>. Furthermore, the inner surface <NUM> can define a void <NUM> extending between the open ends 112a,b of the spring <NUM> and an axis <NUM> extending through a center of the void <NUM>. The opposing open ends 112a,b of the spring <NUM> can allow for fluid flow through the void <NUM>. Moreover, the spring <NUM> can define a spring force. In some aspects, the spring <NUM> can be formed from a plastic material, such as, for example, nylon, POM (polyoxymethylene), or PVC (polyvinyl chloride). In other aspects, the spring <NUM> can be formed from a metal material, such as stainless steel, spring steel, aluminum, nitinol, cobalt chromium, or any other suitable material. Optionally, the material can be an NSF certified material that can comply with various public health safety standards. For example, in some aspects, the material can be approved as safe for use in drinking-water applications. Furthermore, in some aspects, the spring can comprise a corrosion-resistant coating. In some aspects, instead of the spring <NUM>, the stent can comprise a balloon for biasing the stent <NUM> from the compressed configuration <NUM> to the expanded configuration <NUM>, or any other suitable mechanism for expanding the stent <NUM>.

In example aspects, the sealing layer <NUM> can be formed as a continuous, tubular sleeve structure <NUM> defining an outer surface <NUM> and an inner surface <NUM>. The inner surface <NUM> can define an inner diameter of the sealing layer <NUM>, and the outer surface <NUM> can define an outer diameter of the sealing layer <NUM>. The outer diameter of the sealing layer <NUM> can be defined as the diameter of the stent <NUM> (the "stent diameter"). The inner surface <NUM> of the sealing layer <NUM> can engage the outer surface <NUM> of the spring <NUM>. In some aspects, the sealing layer <NUM> can wrap around a circumference of the spring <NUM> and can cover the entire outer surface <NUM> of the spring <NUM>, as shown. However, in other aspects, such as the aspect of <FIG>, the sealing layer <NUM> can wrap around the circumference of the spring <NUM> and can cover only a portion of the outer surface <NUM> of the spring <NUM>. In still other aspects, the sealing layer <NUM> does not wrap around the entire circumference of the spring <NUM>.

Example aspects of the sealing layer <NUM> can comprise a flexible and compressible material, such as, for example, neoprene. In other aspects, the sealing layer <NUM> can be formed from another synthetic rubber material such as EPDM rubber, natural rubber, foam, epoxy, silicone, a resin-soaked cloth, or any other suitable flexible material for providing a watertight seat between the stent <NUM> and the inner wall <NUM> of the pipe <NUM> (pipe <NUM> shown in <FIG>). According to example aspects, the inner diameter of the sealing layer <NUM> can substantially match or be slightly smaller than the outer diameter of the spring <NUM>, such that the sealing layer <NUM> can fit snugly on the spring <NUM>. The sealing layer <NUM> in some aspects can be coupled to the spring <NUM> by a fastener (not shown), such as, for example, stitching, adhesives, ties, or any other suitable fastener known in the art.

In the expanded configuration <NUM>, as shown in <FIG>, the spring force can bias the spring <NUM> and the sealing layer <NUM> radially outward relative to the axis <NUM>, such that each of the spring <NUM> and sealing layer <NUM> define the relatively tubular shapes, as shown. In the expanded configuration <NUM>, the stent <NUM> can define its largest possible stent diameter. In the compressed configuration <NUM>, as shown in <FIG>, a compression force can be applied to the outer surface <NUM> of the sealing layer <NUM> by a compression mechanism (not shown). The compression force can overcome the spring force, and the sealing layer <NUM> and spring <NUM> can compress or fold radially inward towards the void <NUM> to define a smaller stent diameter and a smaller overall stent volume than in the expanded configuration <NUM> (shown in <FIG>). When the compression force is removed or reduced to less than the spring force, the spring force can bias the stent <NUM> back to the expanded configuration <NUM>. In other aspects, instead of a compression force, a tension force (i.e., a pulling force) or any other suitable force can be applied the stent <NUM> to bias the stent <NUM> to the compressed configuration <NUM>.

An expansion ratio can be defined as the ratio between the stent diameter in the expanded configuration <NUM> and the stent diameter in the compressed configuration <NUM>. In example aspects, the expansion ratio can be between about <NUM>/<NUM> and <NUM>/<NUM>. In other aspects, the expansion ratio can be between about <NUM>/<NUM> and <NUM>/<NUM>. In still other aspects, the expansion ratio can be about <NUM>/<NUM>. As will be described in further detail below, in the compressed configuration <NUM>, the reduced stent diameter can allow for easier insertion of the stent <NUM> into a pipeline (not shown) and easier navigation of the stent <NUM> through the pipeline.

Example aspects of the spring <NUM> can be oriented in a rolled configuration <NUM> for use, as shown in <FIG>, and an unrolled configuration <NUM>, as shown in <FIG>. In example aspects, the spring <NUM> can be manufactured in the unrolled configuration <NUM>, and rolled into the rolled configuration <NUM> thereafter for use. Referring to <FIG>, in the unrolled configuration <NUM>, the spring <NUM> can be substantially flat and can define a first end <NUM> and an opposing second end <NUM>. Example aspects of the spring <NUM> can be rolled into the rolled configuration <NUM> from the unrolled configuration <NUM>. The first end <NUM> of the spring <NUM> can be coupled to the second end <NUM> to retain the spring <NUM> in the rolled configuration <NUM>, as shown in <FIG>. According to example aspects, the first end <NUM> can be coupled to the second end <NUM> by a fastener, such as, for example, one or more nut and bolt assemblies <NUM>, as best seen in <FIG>. In other aspects, the fastener can be adhesives, clips, snaps, ties, or any other suitable fastener or combination of fasteners know in the art.

<FIG> illustrates the stent <NUM> according to another aspect of the disclosure, wherein the stent <NUM> is in the expanded configuration <NUM> within a void <NUM> of the pipe <NUM>. The pipe <NUM> is illustrated as translucent for improved visibility of the stent <NUM>. The void <NUM> can be defined by the inner wall <NUM> of the pipe. Like the stent <NUM> of <FIG>, the stent <NUM> of the current aspect comprises the spring <NUM> and the sealing layer <NUM>. In the present aspect, the spring <NUM> can be a wave-pattern spring <NUM>. The wave-pattern spring <NUM> can comprise a metal wire <NUM> defining a wave pattern in the axial direction. The spring <NUM> can be rolled into a tubular structure <NUM> as shown. The spring <NUM> in the rolled configuration <NUM> can define the void <NUM> and the axis <NUM> (shown in <FIG>) extending through the void <NUM>. Example aspects of the void <NUM> can be concentric to the void <NUM> of the pipe <NUM>. The sealing layer <NUM> can form the sleeve <NUM> and can wrap around the circumference of the spring <NUM>, engaging the outer surface <NUM> (shown in <FIG>) of the spring <NUM>. As shown in the present aspect, portions of the spring <NUM> can extend beyond the sealing layer <NUM>, such that the sealing layer <NUM> covers only a portion of the outer surface <NUM> of the spring <NUM>. In other aspects, the sealing layer <NUM> can completely cover the outer surface <NUM> of the spring <NUM>. In still other aspects, the sealing layer <NUM> may not extend around the entire circumference of the spring <NUM>. In the present aspect, the sealing layer <NUM> is coupled to the spring <NUM> by zip ties <NUM>. The zip ties <NUM> can be looped through spring loops <NUM> formed on the spring <NUM> and can engage the material of the sealing layer <NUM> to secure the sealing layer <NUM> to the spring <NUM>. In other aspects, however, a fastener other than the zip ties <NUM> can be used to attach the sealing layer <NUM> to the spring <NUM>, such as, for example, sewing or an adhesive.

As shown, example aspects of the spring <NUM> can further comprise one or more tabs <NUM> extending inward towards the void <NUM>. Each of the tabs <NUM> can define an opening therethrough. In example aspects, a cable (not shown) can pass through the opening of each of the tabs <NUM> and can be tightened to contract the stent <NUM> to the compressed configuration through tension in the cable. The cable can be cut to release the contracting force on the stent <NUM> and to allow the spring <NUM> to bias the stent <NUM> to the expanded configuration <NUM>. In other aspects, the stent <NUM> can be compressed by another compression or contraction mechanism, such as a compression sleeve, a dissolvable wire, or any other suitable mechanisms known in the art. In an aspect comprising a dissolvable wire, the wire can be dissolved by electricity, chemicals, water, or any other suitable dissolving mechanism. In still another aspect, the compression mechanism can be a hose clamp. In some aspects, the hose clamp or other compression mechanism can comprise a worm drive.

With the stent <NUM> in the expanded configuration <NUM> within the pipe <NUM>, the outer surface <NUM> of the sealing layer <NUM> (shown in <FIG>) can press against the inner wall <NUM> of the pipe <NUM> to retain the stent <NUM> in position relative the pipe <NUM>. Furthermore, the sealing layer <NUM> can press against a crack <NUM> in the pipe <NUM>, or other damage to the pipe <NUM>, to seal the crack <NUM> and prevent leakage at the crack <NUM>.

<FIG> illustrates the stent <NUM> of <FIG> with a secondary sealing layer <NUM>. The secondary sealing layer <NUM> can be formed from the same material as the sealing layer <NUM>, or can be formed from a different material. For example, in one aspect, the sealing layer <NUM> can be formed from neoprene and the secondary sealing layer <NUM> can be formed from an epoxy. Other aspects of the sealing layer <NUM> and secondary sealing layer <NUM> can be formed from other materials. In example aspects, the secondary sealing layer <NUM> can be provided for improved sealing capability at the site of the crack <NUM> or other damage. For example, the sealing layer <NUM> can serve as a general sealing solution and can provide support to the secondary sealing layer <NUM>, while the secondary sealing layer <NUM> can serve as a more acute sealing solution. In some example aspects, the secondary sealing layer <NUM> can comprise a compliant material that can be pressed into the crack <NUM> or other damage. Furthermore, in some aspects, the sealing layer <NUM> can comprise a less compliant material configured to provide structure to the stent and support to the secondary sealing layer.

An example aspect of a method for using the stent <NUM> is also disclosed. A compression force (or contraction force in some instances) can be applied to the stent <NUM> to orient the stent <NUM> in the compressed configuration <NUM>, wherein the stent <NUM> has a reduced stent diameter as compared to the stent diameter in the expanded configuration <NUM>. In one aspect, the compression force can be applied by a compression sleeve (not shown) having a smaller diameter than the stent diameter in the expanded configuration <NUM>. In other aspects, the compression force can be applied by cables, ties, or another suitable compression mechanism.

In the compressed configuration <NUM>, the reduced stent diameter and reduced stent volume can allow for easy insertion of the stent <NUM> into the pipeline (not shown) and navigation through the pipeline. The pipeline can comprise one or more pipes, such as the pipe <NUM> shown in <FIG>. According to example aspects, the pipeline can transport a fluid along the pipeline, such as, for example, water, oil, or natural gas. The stent <NUM> can be inserted into the pipeline in the compressed configuration <NUM> at an existing access point. In an example aspect, the existing access point can be a fire hydrant. In other aspects, the existing access point can be the entrance or exit of the pipeline, a service entrance, or another suitable point of entry that allows for easy insertion of the stent <NUM> into the pipeline.

Once inserted into the pipeline, the stent <NUM> can be mechanically driven or motor-driven through the pipeline to the location of the crack <NUM> or other damage. In instances where the stent <NUM> is moving through the pipeline in the direction of the fluid flow, a current of the fluid can assist in moving the stent <NUM> through the pipeline. As the stent <NUM> moves through the pipeline, fluid in the pipeline can continue to flow around and/or through the compressed stent <NUM>. As such, the flow of fluid in the pipeline can continue uninterrupted as the stent <NUM> is navigated through the pipeline. Such a configuration prevents the need to shut off the fluid flow during repairs, which can save costs for the service provider and prevent interruption of service to customers. Furthermore, inserting the stent <NUM> into the pipeline at an existing access point and remotely navigating the stent <NUM> through the pipeline can eliminate the need to dig up the surrounding terrain to access the damaged pipe, which can save time and costs when performing repairs.

The compressed stent <NUM> can be positioned in the pipeline proximate to the crack <NUM> in the pipe <NUM>. The compression force applied to the stent <NUM> by the compression sleeve, or other compression mechanism, can be removed or reduced, such that the spring force can bias the stent <NUM> to the expanded configuration <NUM>. In the expanded configuration <NUM>, the outer surface <NUM> of the sealing layer <NUM> of the stent <NUM> can contact the inner wall <NUM> of the pipe <NUM> and can press against the crack <NUM> to create a watertight seal and prevent leakage at the crack location. In some aspects, a portion of the sealing layer <NUM> can be pushed into the crack <NUM> for an improved seal. In example aspects, fluid pressure from the fluid flow in the pipeline can also assist in biasing the stent <NUM> against the inner wall <NUM> of the pipe <NUM>.

With the stent <NUM> positioned in the pipe <NUM> in the expanded configuration <NUM>, fluid in the pipeline can flow through the void <NUM> in the stent <NUM>. Example aspects of the stent <NUM> can be sized and shaped to fit tightly in the pipeline in the expanded configuration <NUM>. For example, in one aspect, the stent diameter in the fully expanded configuration <NUM> can be slightly greater than a diameter of the inner wall <NUM> of the pipe <NUM>. The tight fit of the stent <NUM> within the pipe <NUM>, along with fluid pressure against the stent <NUM>, can aid in retaining the stent <NUM> in position at the location of the crack <NUM> or other damage. In some aspects, the stent <NUM> in the expanded configuration <NUM> can also serve to add structural integrity to the pipe <NUM>. In such aspects, the stent <NUM> can be formed from materials of a sufficient strength and can be provided with a sufficient spring force for providing structural support to the pipe <NUM> at the location of the stent <NUM>. Some aspects of the stent <NUM> further can include a fastener for attaching the stent <NUM> to the inner wall <NUM> of the pipe <NUM>, such as, for example, an adhesive. However, in other aspects, any other suitable fastener known in the art can be used to attach the stent <NUM> to the pipe <NUM>.

Example aspects of the spring <NUM> can be cut from a sheet <NUM> of material. Referring to <FIG>, the spring <NUM> of <FIG> can be cut from a flat sheet <NUM> of metal material, such as, for example, stainless steel. Other aspects of the spring <NUM> can be formed from a sheet <NUM> of another material, such as spring steel, aluminum, plastic, nitinol, or any other suitable material in sheet form. A pattern of the spring <NUM>, such as the wave pattern <NUM> depicted, can be etched, stamped, or otherwise cut into the sheet <NUM>, and any excess sheet material <NUM> can be removed.

In another aspect, the spring <NUM> can be formed from a wire (not shown) and worked into the wave-pattern shape of the wave-pattern spring <NUM>. For example, the wire can be hot worked or cold worked into the wave-pattern shape. In other aspects, the wire can be worked into another desired spring shape. Furthermore, in example aspects, after working the wire into the desired shape, the spring <NUM> can be heat treated to allow the spring <NUM> to retain a spring temper.

<FIG> illustrates the spring <NUM> in the unrolled configuration <NUM> with the excess sheet material <NUM> removed. As shown, the spring <NUM> can define the first end <NUM> and the opposite second end <NUM>. The first end <NUM> can define a pair of L-shaped hooks <NUM> extending downwardly therefrom, relative to the orientation shown. The second end <NUM> can define a pair of mating L-shaped hooks <NUM> extending upwardly therefrom, relative to the orientation shown. The spring <NUM> can be rolled to define the tubular structure <NUM> shown in <FIG>, and the hooks <NUM> at the first end <NUM> can engage the mating hooks <NUM> at the second end <NUM> to retain the spring <NUM> in the rolled configuration <NUM>.

<FIG> illustrates another aspect of the spring <NUM>. In this aspect, the spring <NUM> can be a wave pattern spring <NUM> substantially similar to the spring <NUM> of <FIG>; however, the spring <NUM> can define a length L<NUM> greater than a length L<NUM> (shown in <FIG>) of the spring <NUM>. For example, in one aspect, the spring <NUM> can define a length L<NUM> of between about <NUM> inches and <NUM> inches, and in other aspects, the spring <NUM> can define a length L<NUM> of about <NUM> inches. Furthermore, in one aspect, the spring <NUM> can define a length L<NUM> of between about <NUM> inches and <NUM> inches, and in other aspects, the spring <NUM> can define a length L<NUM> of about <NUM> inches. In other aspects, the lengths L<NUM>, L<NUM> of the springs <NUM>,<NUM>, respectively, can be greater or less than the example aspects described, and this disclosure should not be viewed as limiting.

<FIG> illustrates an exploded view of another aspect of the stent <NUM>. As shown, the stent <NUM> can comprise the spring <NUM> and the sealing layer <NUM>. In the present aspect, the spring <NUM> can be a torsion spring <NUM>. In the compressed configuration, a twisting force can be applied to the torsion spring <NUM>, such that a diameter of the torsion spring <NUM> and the overall stent diameter can be reduced. In the expanded configuration, the twisting force can be removed and the torsion spring <NUM> can spring radially outward, biasing the sealing layer <NUM> radially outward against the inner wall <NUM> of the pipe <NUM> (shown in <FIG>).

In one exemplary aspect, a stent for repairing a pipe can comprise a spring, the spring defining an outer surface and an inner surface, the inner surface defining a void; and a seal on the outer surface of the spring, the stent configurable in a compressed orientation, wherein the spring is compressed, and an expanded orientation, wherein the spring is expanded.

In a further exemplary aspect, a compression force can be applied to the stent in the compressed orientation by a compression mechanism. In a further exemplary aspect, the compression mechanism is selected from one of a compression sleeve, a cable, a hose clamp, and a dissolvable wire. In a further exemplary aspect, a diameter of the stent in the compressed orientation can be smaller than a diameter of the stent in the expanded orientation. In a further exemplary aspect, the spring can comprise at least one of stainless steel, spring steel, nitinol, aluminum, nylon, polyoxymethylene, and polyvinyl chloride. In a further exemplary aspect, the seal can comprise a flexible material, and the flexible material can comprise at least one of foam, natural rubber, synthetic rubber, epoxy, a resin-soaked cloth, and silicone. In a further exemplary aspect, the stent can define a cylindrical structure in the expanded orientation, and the cylindrical structure can define a pair of opposing open ends. In a further exemplary aspect, the spring can define a pattern, and the pattern can be selected from one of a mesh pattern and a wave pattern. In a further exemplary aspect, the seal can be attached to the spring by a fastener. In a further exemplary aspect, the spring can be configurable in an unrolled configuration and a rolled configuration, the spring can define a first end and a second end, and the first end can be attached to the second end in the rolled configuration. In a further exemplary aspect, the spring can comprise sheet metal.

In another exemplary aspect, a pipe assembly can comprise a pipe comprising an inner wall, the inner wall defining a first void; and a stent comprising a spring and a seal, the stent configurable in a compressed orientation and an expanded orientation, the seal defining an outer surface, the outer surface engaging the inner wall in the expanded configuration.

In a further exemplary aspect, the inner wall can define an inner diameter of the pipe and the seal can define an outer diameter of the stent. In a further exemplary aspect, the outer diameter of the stent in the compressed orientation can be smaller than the inner diameter of the pipe. In a further exemplary aspect, the outer diameter of the stent in the expanded orientation can be greater than or equal to the inner diameter of the pipe. In a further exemplary aspect, the spring can define an inner spring surface, the inner spring surface can define a second void, and the second void can be concentric to the first void.

In another exemplary aspect, a method for repairing a pipe can comprise compressing a stent, the stent comprising a spring and a seal; inserting the stent into the pipe; positioning the stent proximate to a leak in the pipe; and expanding the stent to cover the leak with the seal.

Claim 1:
A stent (<NUM>) for repairing a leak in a pipe carrying water, gas, and/or oil, the stent comprising:
a spring (<NUM>) comprising a metal wire (<NUM>) rolled into a tubular structure (<NUM>), wherein the spring defines a wave pattern, the spring defining an outer surface and an inner surface, the inner surface defining a void (<NUM>); and
a sealing layer (<NUM>) of a seal wrapped around the outer surface of the spring, wherein the sealing layer is coupled to the spring by zip ties (<NUM>), the zip ties being looped through spring loops (<NUM>) formed on the spring and engaging material of the sealing layer so to secure the sealing layer to the spring,
the stent being configurable in a compressed orientation, where the spring is compressed, and in an expanded orientation, where the spring is expanded, the spring biasing the stent to the expanded orientation.