Patent Description:
Many liquids and gases are transported overland via pipelines, which extend for hundreds of kilometers. These pipelines are subject to ageing, corrosion, cracks, earthquakes and other impacts, which can cause minor or major leakage. The leakage may be difficult to detect and yet more difficult to stop.

A leakage may be discovered by a sharp pressure-drop over the length of the pipeline, or by emission of the gas/liquid from the pipeline. This may lead to significant environmental pollutions and to massive financial loss. The repair of underground pipelines poses a series of complicated technological problems considering the relevant factors, including, difficult accessibility, partial or complete replacement of part of the pipeline, or in situ pipeline repair.

<CIT> describes a method of in-situ repair by injecting specific chemical substances from both sides of a damaged leakage location.

<CIT>, describes a method of repairing leakage in pipelines. The method includes the steps of forming a first and second openings (14a, 14b) in the pipeline (<NUM>) upstream and downstream, respectively, of the leakage location, inserting through the first opening (14a) a first body (C1), filling the space arrear of the first body (C1) with a first viscous sealing material (M1), inserting through the first opening (14a) a second body (C2) arrear of the first viscous sealing material (M1) compressing the first sealing material by applying a pressure against the first and the second bodies (C1, C2) in opposite directions, causing the first and second bodies (C1, C2) and the compressed first sealing material (M1) to move in unison in the direction of the second opening (14b), and retrieving the first and second bodies (C1, C2). Preferably, the method is performed using three bodies (C1, C2, C3) and two sealing materials (M1, M2).

<CIT> provides pipeline pigs for maintenance of a pipeline, the pig including two adjacent ovular sections generally symmetrically disposed about a vertical axis, a polymeric band disposed along the vertical axis, the band being adapted to reduce a cross section of the pig along the axis and a longitudinal inner support member disposed centrally along the ovular sections and perpendicularly to the vertical axis.

<CIT>, describes systems for curing a leakage in a pipeline, the system including at least one gel pig and at least one sealant composition; wherein the at least one gel pig and the at least one sealant composition form a pig train, adapted to move along the pipeline to a region of the leakage and to seal the leakage.

<CIT>, describes methods for curing a leakage in a pipeline, the system including at least one gel pig and at least one sealant composition; wherein the at least one gel pig and the at least one sealant composition form a pig train, adapted to move along the pipeline to a region of the leakage and to seal the leakage.

<CIT>, provides leakage plugging devices and methods for sealing a leakage at a remote site in a pipe, the device including a porous carrier plug of a deformable material including pores and at least one sealant composition disposed in the pores, wherein the porous carrier plug is adapted to transport the at least one sealant composition from a first site to a remote site and to plug the leakage at the remote site.

Many industrial applications use fibers. Typically, fibers are used in compositions for building purposes. Some fibers are in the form of a yarn, that is, a continuous often-plied strand composed of either natural or man-made fibers or filaments.

In one non-limiting example, hemp yarn has a size of Nm <NUM> (Nm <NUM> yarn = <NUM>,<NUM> meters per kilogram, or about <NUM>,<NUM> yards per pound) from single to multiple plies of <NUM>, <NUM>, <NUM>, <NUM> and <NUM> in either natural or bleached (using peroxide) Made from earth-friendly wet spun hemp, these yarns are smooth and durable The yarns may be provided on spools or in packages and may be single-ply, <NUM>-ply, <NUM>-ply, <NUM>-ply, <NUM>-ply and <NUM>-ply or combinations thereof.

Several technologies have been developed to seal mains pipelines, but there remains a need to seal lateral pipelines. In many urban communities, up to <NUM>% of the total water is lost due from a large number of service and lateral pipes.

Thus, there still remains a need for improved methods for sealing leaks in lateral pipelines.

The present invention provides a method according to claim <NUM> and a system according to claim <NUM> for sealing at least one leak in at least one of at least one lateral pipe and a mains pipe, the method including passing a at least one of a pig train and said sealant composition under pressure along at least one of said main pipeline and said at least one lateral pipe such that a portion of the sealant composition enters at least one leakage site to seal and cure the at least one leak.

It is an object of some aspects of the present invention to provide methods for sealing leaks in lateral pipelines.

In some embodiments of the present invention, improved methods are provided for sealing leaks in lateral pipelines.

In other embodiments of the present invention, pipeline sealant compositions are provided for sealing lateral pipeline leaks. The mains pipelines may be of any length. The lateral pipes are typically, but not necessarily less than <NUM>, <NUM> or <NUM>. Typically, lateral pipes have internal diameters of <NUM>/<NUM>, ½, ¾, <NUM>, <NUM> and <NUM> inches. The pipes or pipelines may be made of any suitable material or material combination, selected from, but not limited to, cast iron, ductile iron, steel, HDPE/MDPE, PVC and the like.

In additional embodiments for the present invention, quick-curing pipeline sealant compositions are provided which are introduced into a mains line in order to seal a leak in a lateral pipeline.

The present invention provides a method of sealing a leak in a lateral pipe, the method including passing a repair composition under pressure along a main pipeline such that a portion of the repair composition enters the lateral pipe from the main pipeline and allowing the portion to reach the leak and to seal the leak.

According to several embodiments, in some case, the terminus of the lateral is isolated (i.e. terminated or valved off) and the sealant composition or pig train is drawn into the lateral by virtue of the leakage flow alone. According to other embodiments, a tap is disposed at the terminus of the lateral pipe to discharge liquid thus compensating for cases where the leakage flow alone is small.

There is thus provided according to an embodiment of the present invention, a method for sealing a leak in a lateral pipe, the method including;.

There is thus provided according to another embodiment of the present invention, a method for sealing a leak in a second lateral pipe, the method comprising:.

There is thus provided according to another embodiment of the present invention, a method for sealing a leak in a first lateral pipeline, the method comprising:.

The present invention provides systems and methods for curing a leakage in a pipeline, the system including at least one fiber-in-liquid sealant composition and at least one gel pig; wherein the at least one gel pig and the at least one fiber-in-liquid sealant and form a pig train, adapted to move along the pipeline to a region of the leakage and to seal the leakage.

There is thus provided according to an embodiment of the present invention, a system for curing at one leakage site in a pipeline, the system including;.

A non-limiting example of a sealant composition is:.

Additionally, according to an embodiment of the present invention, the main pipeline and lateral pipe are adapted to convey a fluid selected from the group consisting of water, oil, gas, petrol, a heating fluid and a cooling fluid.

Moreover, according to an embodiment of the present invention, the repair composition is disposed in a repair composition train.

Further, according to an embodiment of the present invention, the repair composition train includes two pigs with the repair composition disposed therebetween.

Furthermore, according to an embodiment of the present invention, the repair composition train includes a rear pig and the repair composition.

Yet further, according to an embodiment of the present invention, the repair composition train includes three pigs with the repair composition disposed between a first and a second the pigs and a second repair composition disposed the second and a third pig.

Additionally, according to an embodiment of the present invention, the pigs are liquid phase pigs.

Additionally or alternatively, according to an embodiment of the present invention, the pigs are solid phase pigs.

Importantly, according to an embodiment of the present invention, the repair composition is at a temperature of <NUM>-<NUM>.

Additionally, according to an embodiment of the present invention, the repair composition includes;.

Moreover, according to an embodiment of the present invention, the liquid phase pigs include;.

Further, according to an embodiment of the present invention, the liquid phase pigs further include;.

Additionally, according to an embodiment of the present invention, the liquid phase pigs further include an oil.

Yet further, according to an embodiment of the present invention, the leak is selected from the group consisting of a hole, a crack, a corroded section and combinations thereof.

It should be noted that according to an embodiment of the present invention, the leak loses <NUM>-<NUM>,<NUM><NUM>/hr of the fluid.

Additionally, according to an embodiment of the present invention, the method further includes sealing at least one leak in the main pipeline.

Additionally or alternatively, according to an embodiment of the present invention, the method further includes sealing a plurality of leaks in a plurality of lateral pipes.

Furthermore, according to an embodiment of the present invention, the pressure is in a range of <NUM>-<NUM> bar.

Moreover, according to an embodiment of the present invention, at least part of the rear pig and at least a portion of the repair composition enter the lateral pipe.

Additionally, according to an embodiment of the present invention, the seal is formed in less than twenty minutes after reaching the leak.

Further, according to an embodiment of the present invention, the seal is formed in less than five minutes after reaching the leak.

Additionally, according to an embodiment of the present invention, the seal is cured in less than three hours after sealing the leak.

There is thus provided according to an embodiment of the present invention, a system for sealing a leak in a lateral pipe from a main pipeline, the system including;.

Additionally, according to an embodiment of the present invention, the at least one repair composition includes two repair compositions.

Further, according to an embodiment of the present invention, the at least one pig includes one pig.

Additionally, according to an embodiment of the present invention, the at least one pig includes two pigs.

Furthermore, according to an embodiment of the present invention, the at least one pig includes three pigs.

Additionally, according to an embodiment of the present invention, the at least one pig includes a gel pig.

Moreover, according to an embodiment of the present invention, the at least one pig includes a plurality of gel pigs.

Further, according to an embodiment of the present invention, the method further includes enabling remains of the repair composition to return to the main pipeline after sealing the leak.

Additionally, according to an embodiment of the present invention inlet and outlet valves of the main pipeline section are closed.

The invention will now be described in connection with certain preferred embodiments with reference to the following illustrative figures so that it may be more and fully understood.

With specific reference now to the figures in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of the preferred embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the invention. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the invention may be embodied in practice.

In all the figures similar reference numerals identify similar parts.

In the detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that these are specific embodiments and that the present invention may be practiced also in different ways that embody the characterizing features of the invention as described and claimed herein.

The pigs, sealant compositions, carrier fluid compositions and chips used in the present invention may be any described in the following patents/patent applications: <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT> and <CIT>.

Reference is now made to <FIG>, which is a simplified schematic diagram of a system <NUM> for curing a leak <NUM> in a lateral (service) pipe <NUM>, connected to a mains pipe <NUM>, in accordance with an embodiment of the present invention.

A sealant composition and/or pig train <NUM> is fed from a mains pipe <NUM> into the service pipe <NUM> and seals the leak/hole/crack <NUM>. The sealant composition and/or pig train <NUM> exits the mains pipe in a flow stream <NUM> (having been introduced into the mains pipe at entry <NUM>. For all examples in this invention, network valves are closed upstream (valve <NUM>) and downstream (valve <NUM>) is open and, if required, a service pipe valve <NUM> is also closed. The closure of network valves is typically several hundred meters (D) away from the service pipe. The service pipe valve is closed during the leak curing process. It should be understood that this figure is a simplification of the actual pipe network, which comprises numerous service pipes, some of which leak and some of which are intact. This methodology is repeated for each hole/crack etc. in each service pipe until no further leaks are detected.

The pig train and/or sealant composition will typically not enter an intact service pipe due a lack of flow thereof into it.

It should be noted that the methods and systems of the present invention, there is no set limit on the length of the lateral. According to some embodiments, there is an upper diameter limit of <NUM>" for the laterals. In practice, a length of a lateral pipe is typically, but not always, less than <NUM>-<NUM> meters.

Reference is now made to <FIG>, which is a simplified schematic diagram of another system <NUM> for curing a small leak <NUM> in a lateral (service) pipe <NUM> connected to a mains pipe <NUM>, in accordance with an embodiment of the present invention.

A sealant composition and/or pig train <NUM> is fed from a mains pipe <NUM> into the service pipe <NUM> and seals the leak/hole/crack <NUM>. The sealant composition and/or pig train (not shown) exits the mains pipe in a flow stream <NUM> (having been introduced into the mains pipe at entry <NUM>. For all examples in this invention, network valves are typically closed upstream (valve <NUM>) and downstream (valve <NUM>) is open. In this case a service pipe valve <NUM> is open to induce a flow of <NUM>-<NUM>/hr out of valve <NUM> into the lateral pipe to seal the leakage <NUM>, in passing through.

The closure of network valves is typically several hundred meters (D) away from the service pipe. The service pipe valve is closed during the leak curing process. It should be understood that this figure is a simplification of the actual pipe network, which comprises numerous service pipes, some of which leak and some of which are intact. This methodology is repeated for each hole/crack etc. in each service pipe until no further leaks are detected.

The pig train and/or sealant composition will typically not enter by any significant measure into a service pipe if the flow into said service pipe is too low.

Turning to <FIG>, there is seen another simplified schematic diagram of a system <NUM> for curing a leak <NUM> in a lateral (service) pipe <NUM>, in accordance with an embodiment of the present invention. In this case, a sealant composition and/or pig train <NUM> is fed in from the service pipe and exits through the hole/crack <NUM> via small stream <NUM> from the service pipe and in main stream <NUM> from a mains pipe <NUM>. For sake of simplicity, not all pumps, valves etc. are not all shown in the ensuing diagrams. The upstream service pipe <NUM> is closed by means of a valve <NUM>.

Additionally, <FIG> shows a simplified schematic diagram of a system <NUM> for curing a leak <NUM> in a second lateral (service) pipe <NUM>, in accordance with an embodiment of the present invention. In this case, the sealant composition and/or pig train <NUM> is fed in through a first service pipe <NUM>, travels through a mains pipe <NUM> in stream <NUM> to the second service pipe and exits the second service pipe in stream <NUM> through the hole/crack etc. Valves <NUM> and303 in the mains pipe are closed.

Reference is now made to <FIG>, which is a simplified schematic diagram of different types of leaks <NUM>, <NUM> in a mains <NUM> or lateral (service) pipe <NUM>, in accordance with an embodiment of the present invention. Leak <NUM> is a leak along a connection/weld area between the service pipe and the mains, leading to a fracture/longitudinal leak area <NUM>. Leak <NUM> is due to a misalignment of two parts of the mains pipe, leading to a spray of the liquid <NUM> out of the leak. Many other examples of pipe leaks exist and these examples are not meant to be limiting, but rather exemplary. The liquid or fluid (such as water) <NUM> flows along a mains pipe <NUM> and leaks at leaks <NUM> and <NUM>. Some of the liquid exits a service pipe <NUM> in stream <NUM> and some in stream <NUM> from the mains pipe. The total liquid leaked is the leakage volume of =<NUM>- (<NUM>+<NUM>).

Turning to <FIG>, there is seen a simplified schematic diagram of a system <NUM> for curing a leak site <NUM> in a mains pipe <NUM>, in accordance with an embodiment of the present invention. A leak flow <NUM> exits leak site <NUM>. A sealant composition and/or pig train <NUM> is fed via a service pipe <NUM> into the mains pipe. It exits the mains pipe in stream <NUM>.

Additionally, <FIG> shows another simplified schematic diagram of a system <NUM> for curing a leak <NUM> exiting from a leak site <NUM> in a mains pipe <NUM>, in accordance with an embodiment of the present invention. A sealant composition and/or pig train <NUM> is fed via a first service pipe <NUM> into the mains pipe. It exits the mains pipe via second service pipe <NUM> in stream <NUM>.

Reference is now made to <FIG>, which is a simplified schematic diagram of a system <NUM> for curing a leak <NUM> from a leak site <NUM> in a branch pipe <NUM>, in accordance with an embodiment of the present invention. A flow of a liquid <NUM> passes in a mains pipe <NUM>. In order to cure leak <NUM>, flow in the mains pipe <NUM> is stopped by valve <NUM>, downstream of the branch pipe. This increases the pressure of flow <NUM> and allows a sealant composition and/or pig train to travel from <NUM> into the branch pipe and to seal and cure leak site <NUM>.

Turning to <FIG>, there is seen a simplified schematic diagram of a system <NUM> for curing a leak flow <NUM> from a leak site <NUM> in a riser pipe <NUM>, in accordance with an embodiment of the present invention. Typically a mains pipe <NUM> is at a depth of a+b from a ground level <NUM>. A riser pipe <NUM> conveys fluids from the mains to one or more service/lateral pipes <NUM> to one or more commercial or residential buildings <NUM>, at a depth a. In order to cure leak <NUM>, a sealant composition and/or pig train travels via flow <NUM> up the riser pipe and out of the lateral pipe at flow <NUM> and seals and cures the leak in the riser pipe en passant. Additionally or alternatively, this may be performed in the opposite direction.

Additionally, <FIG> shows a simplified schematic diagram of a system <NUM> for curing a leak <NUM> in a secondary service (lateral) pipe <NUM>, in accordance with an embodiment of the present invention. A pig train is introduced to a mains pipe <NUM> in a flow <NUM>. Some of the liquid flows into a primary service pipe or riser <NUM> and then into secondary lateral pipe <NUM> (but not into secondary lateral pipe <NUM>, into which there is no leak). If there is sufficient liquid, it flows through the leak area, the flow of sealant composition will seal and cure leak <NUM> en passant. Valves <NUM> and <NUM> are closed. The sealant composition exits the system at flow <NUM> out of hole/crack <NUM> and <NUM>. In some cases, flow <NUM> will be stopped with a suitable valve or other mechanical device.

Reference is now made to <FIG>, which is another simplified schematic diagram of a system <NUM> for curing a leak <NUM> in a secondary service (lateral) pipe <NUM>, in accordance with an embodiment of the present invention. A plurality of secondary lateral pipes <NUM>, <NUM> and <NUM> provide residential buildings <NUM>, <NUM> and <NUM> with water from a mains pipe <NUM>, via a riser or primary service pipe <NUM>.

A sealant composition and/or pig train is introduced to a mains pipe <NUM> in a flow <NUM>. Some of the liquid flows into the primary service pipe or riser <NUM>, and then into lateral <NUM>. Valves931, <NUM>, <NUM> and <NUM> are closed. If there is sufficient liquid flow through the leak area, the flow of sealant composition will seal and cure leak <NUM> with flow <NUM> through the leak/crack/hole. The sealant composition and/or pig train exits the system at flow <NUM>.

Turning to <FIG>, there is seen a simplified schematic diagram of a system <NUM> for curing a large leak <NUM> in a branch pipe <NUM>, in accordance with an embodiment of the present invention. A sealant composition and/or pig train is introduced to a mains pipe <NUM> in a flow <NUM>. Valve <NUM> stoppers the mains pipe <NUM> or by any other suitable flow stopping device. The sealant composition and/or pig train passes through the branch pipe in flow <NUM> past the leak <NUM>. A large volume of sealant <NUM> passes through the leak until it is sealed and cured. The sealant composition and/or pig train exits the system at flow <NUM>.

Reference is now made to <FIG>, which is a simplified schematic diagram of a system <NUM> for curing a leak <NUM> from a leak site <NUM> in a residential buried pipe <NUM>, in accordance with an embodiment of the present invention. A sealant composition and/or pig train is introduced to a lateral pipe <NUM>. The lateral pipe has one or more fluidly-connected secondary laterals <NUM>, <NUM>, each servicing one or more residential buildings <NUM>, and <NUM>, <NUM>, respectively. Residential building <NUM> comprises a number of apartments <NUM>, <NUM>, <NUM> and <NUM>. Residential building <NUM> and <NUM> are houses, for example. A continuation of pipe <NUM> is pipe <NUM>, which leads to a boundary box <NUM>, disposed on a boundary line <NUM>, separating private residential ground <NUM> from municipal property <NUM>. Another lateral <NUM> connects the boundary box to a mains pipe <NUM>.

The sealant composition and/or pig train flows along lateral <NUM> to pipe <NUM>. The boundary box may comprise at least one meter <NUM> and at least one valve <NUM>. Leak site <NUM> having leak <NUM> is cured by the sealant composition and/or pig train. The pig train and/or fluid flow <NUM> may be recovered at a tap <NUM> (optionally introduced for the purpose of sealing the pipeline), disposed before/in front of the boundary box, which is in fluid connection via a pipe <NUM>. When performing the sealing and/or curing process as described above, all water valves and/or taps in the residences need to be turned off and, boundary box valve <NUM> needs to be closed.

In some alternate embodiments, the flow direction of the pig train/sealant composition is from pipe <NUM> into lateral pipe <NUM> to cure leak <NUM> and the fluid flow exits via pipe <NUM>.

By lateral pipe is meant any service pipe, communication pipe, small pipe, non-mains pipe being connected to a mains pipe in various types of connections and orientations, often, but not necessarily, at an angle of <NUM>°.

Repair method "inside" lateral (diversion) line pipe.

The present invention relates to a process for repairing pipes, tubing from the "inside", in particular, to methods of repair lateral line pipes.

In accordance with this method, repair materials are fed into a mains pipe, from which the lateral pipe is in fluid connection. The repair materials are fed under pressure into and at a constant speed along the mains pipeline. Upon passing the junction/connection between the main pipeline and the service pipe, some of the repair material passes up the service pipe to the area of the leak and then through the hole/crack, where it hardens after sealing it, leading to the curing of the service pipe. This eliminates or significantly reduces leakage from the service pipe. Some aspects of the present invention provide novel methods and systems for increased reliability in the sealing of leakages in lateral pipes.

At the same time it is assumed to simplify the process of repair of such pipes and avoiding the need to excavate. This goal is achieved by the fact that the repair material is fed into the lateral pipe to be repaired through the main pipe. Thus, the repair material passes as for repair of the main pipe in one direction (one end of the pipeline to the other). After the repair the remaining material is returned to the place of loading and flushed out of the pipe to be repaired.

Another non-limiting example of sealant composition <NUM> is:.

Another non-limiting example of composition <NUM> is:.

Typically, fibers are used in compositions for building purposes. Some fibers are in the form of a yarn, that is, a continuous often-plied strand composed of either natural or man-made fibers or filaments.

In one non-limiting example, hemp yarn has a size of Nm <NUM> (Nm <NUM> yarn = <NUM>,<NUM> meters per kilogram, or about <NUM>,<NUM> yards per pound) from single to multiple plies of <NUM>, <NUM>, <NUM>, <NUM> and <NUM> in either natural or bleached (using peroxide) Made from earth-friendly wet spun hemp, these yarns are smooth and durable The yarns may be provided on spools or in packages and may be single-ply, <NUM>-ply, <NUM>-ply, <NUM>-ply and <NUM>-ply or combinations thereof.

The pigs, sealant compositions, carrier fluid compositions and chips used in the present invention may be any described in the following patents/patent applications, incorporated herein by reference:- <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT> and <CIT>.

The references cited herein teach many principles that are applicable to the present invention.

It is to be understood that the invention is not limited in its application to the details set forth in the description contained herein or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Those skilled in the art will readily appreciate that various modifications and changes can be applied to the embodiments of the invention as hereinbefore described without departing from its scope, defined in and by the appended claims.

Claim 1:
A method for sealing at least one leak (<NUM>, <NUM>, <NUM>) in at least one of a mains pipe (<NUM>, <NUM>, <NUM>) and at least one lateral pipe (<NUM>, <NUM>, <NUM>), the method comprising:
passing at least one pig train comprising at least one gel pig and at least one sealant composition (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising at least one of wound fibers and yarns, under pressure along the mains pipe (<NUM>, <NUM>, <NUM>) and said at least one lateral pipe (<NUM>, <NUM>, <NUM>) such that a portion of said pig train (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) enters said at least one leakage site to seal said at least one leak (<NUM>, <NUM>, <NUM>).