Patent Description:
Many liquids are transported via subterranean/underwater pipelines. When a leakage crack or hole forms in the pipeline, the liquid leaks therefrom. Often, it takes a long time to detect a leakage and yet longer to locate the leakage site. Oil, gas and water transportation are thus subject to tremendous losses due to pipeline leakage.

There is thus a need to maintain and seal leaky subterranean/underwater pipelines quickly in situ. A non-limiting example could be potable water pipes that leak due to defects in the pipe materials. These could be defective lead-run cast iron joints, defective asbestos cement collars, longitudinal cracks in PVC pipes and in ferrous pipes caused by hoop stress, split bell caused by transverse stresses on the pipe joint, circumferential breaks due to longitudinal thermal contraction, displaced 'O' rings on PVC joints, failed welds on MDPE joints and service connections on the external ferrule connecting the customer service pipe to the mains. Typical leak sizes can range from <NUM> liters-per-hour to <NUM>,<NUM> liters-per-hour. <CIT> discloses systems and 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.

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> 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.

There still remains an urgent need to develop systems and methods for sealing and curing pipeline leakages, with long-term curing effects.

It is an object of some aspects of the present invention to provide methods of forming fiber-in-liquid sealant compositions for use in systems and methods for sealing and/or curing pipeline leakages. The cured pipelines have been tested for long-term curing. It has been found that the longevity of cured pipes applying the fibers- in-sealant composition exceeds <NUM> to <NUM> years.

The present invention provides a system according to claim <NUM>. Embodiments of the invention are defined by the dependent claims. The fibers may be in a yarn (a continuous often-plied strand, composed of either natural or man-made fibers or filaments).

The system may be provided for sealing water transport pipelines.

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

Furthermore, according to an embodiment of the present invention, the at least one gel pig includes two gel pigs and the at least one FISIC composition in a carrier fluid includes one FISIC composition.

Further, according to an embodiment of the present invention, the at least one gel pig includes three gel pigs and the at least one FISIC composition includes two FISIC compositions.

Moreover, according to an embodiment of the present invention, the pig train is adapted to move along the pipeline at a speed of <NUM> to <NUM>/s.

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

Furthermore, according to an embodiment of the present invention, the at least one of the two pigs has an average diameter of at least <NUM>% less than an internal diameter of the pipeline.

Additionally, according to an embodiment of the present invention, at least one of the two pigs has an average diameter of at least <NUM>% less than an internal diameter of the pipeline.

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

Furthermore, according to an embodiment of the present invention, the at least one gel pig further includes;.

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

Moreover, according to an embodiment of the present invention, the at least one gel pig includes a rear pig and a front pig of different compositions.

Additionally, according to an embodiment of the present invention, the pig train is adapted to conform to an inner profile of the pipeline.

Furthermore, according to an embodiment of the present invention, the inner profile of the pipeline is reduced in diameter in at least one section by at least <NUM>%.

Additionally, according to an embodiment of the present invention, the inner profile of the pipeline is reduced in diameter in at least one section by at least <NUM>%.

Further, according to an embodiment of the present invention, the inner profile of the pipeline is reduced in diameter in at least one section by at least <NUM>%.

Yet further, according to an embodiment of the present invention, the inner profile of the pipeline is further increased in the diameter in at least one section by at least <NUM>%.

Additionally, according to an embodiment of the present invention, the inner profile of the pipeline is increased in the diameter in at least one section by at least <NUM>%.

Importantly, according to an embodiment of the present invention, the inner profile of the pipeline is increased in the diameter in at least one section by at least <NUM>%.

Additionally, according to an embodiment of the present invention, the system further includes said pipeline and a pressurized fluid for propelling the system from a first end thereof along the pipeline.

Furthermore, according to an embodiment of the present invention, the pressurized fluid includes a liquid.

Additionally, according to an embodiment of the present invention, the pressurized fluid includes a gas.

Furthermore, according to an embodiment of the present invention, the pressurized fluid includes a tri-phase composition.

Additionally, according to an embodiment of the present invention, the pressurized fluid is at a pressure of <NUM>-<NUM> bar.

Moreover, according to an embodiment of the present invention, the pig train is adapted to prevent a bypass of a propelling product by of more than <NUM>%.

Additionally, according to an embodiment of the present invention, the pig train is adapted to be extracted from the pipeline via a conduit of less than two inch diameter at a pressure of less than <NUM> bar.

Additionally, according to an embodiment of the present invention, the system further includes a counter pressurized fluid for counter-pressurizing the pig train from a second end thereof.

Furthermore, according to an embodiment of the present invention, the counter pressurized fluid is for controlling velocity of movement of the pig train along the pipeline.

Additionally, according to an embodiment of the present invention, the pig train can be launched from a pipe of a diameter of less than <NUM>% of the pipeline.

Further, according to an embodiment of the present invention, the pig train can be launched from a pipe of a diameter of less than <NUM>% of the pipeline.

Additionally, according to an embodiment of the present invention, herein the pig train can be launched from a pipe of a diameter of less than <NUM>% of the pipeline.

Additionally, according to an embodiment of the present invention, A the pig train can be launched from a pipe at an angle of greater than <NUM>° to the pipeline.

Further, according to an embodiment of the present invention, the pig train can be launched from a pipe at an angle of greater than <NUM>° to the pipeline.

Yet further, according to an embodiment of the present invention, the pig train can be launched from a pipe at an angle of greater than <NUM>° to the pipeline.

Additionally, according to an embodiment of the present invention, the pig train can be launched from a pipe at a pressure in the range of <NUM>-<NUM> bar.

Moreover, according to an embodiment of the present invention, the pig train can be launched from a pipe at a pressure of <NUM> - <NUM> bar.

Additionally, according to an embodiment of the present invention, the pig train is adapted to travel through an obstruction in the pipeline and to be operative thereafter.

Further, according to an embodiment of the present invention, the obstruction selected from the group consisting of tuberculation, encrustation, a butterfly valve, a wedge, a nail, a screw, an obstructing element, an in-pipe meter, a service pipe ferrule, a baffle, a broomstick seal and combinations thereof.

The present invention will be more fully understood from the following detailed description of the preferred embodiments thereof, taken together with the drawings.

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 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.

Reference is now made to <FIG>, which is a simplified pictorial illustration showing a system <NUM> for sealing a pipeline, in accordance with an embodiment of the present invention.

System <NUM> is constructed and configured to seal a pipeline <NUM> comprising at least one leakage site <NUM>, such as a crack or hole.

By "seal" or "sealing", is meant stopping flow from a leakage site, such as a crack or hole.

By "cure" or "curing" is meant permanently preventing flow from a leakage site, such as a crack or hole, enduring pressure, temperature and other environmental changes for extensive periods of time. The cure may last one or more years, one or more decades or longer.

System <NUM> comprises a sealant composition comprising fibers in a carrier fluid <NUM> (termed herein fibers-in-sealant-in-carrier (FISIC) composition, per fibers-in-sealant composition (FISIC) <NUM>, <FIG> hereinbelow) and at least one gel pig <NUM>. System <NUM> is adapted to travel along the pipeline using a first pressure force <NUM> to the rear of the gel pig and a counter force <NUM> upstream (lesser than force <NUM>). Some non-limiting examples of the gel pig compositions appear in the examples hereinbelow. Some non-limiting examples of the sealant compositions are hereinbelow in table <NUM>.

A non-limiting example of fibers-in-sealant-in-carrier (FISIC) composition <NUM> is:.

Another non-limiting example of fibers-in-sealant-in-carrier (FISIC) composition <NUM> is:.

Another non-limiting example of fibers-in-sealant-in carrier fluid (FISIC) composition <NUM> is:.

Additionally, according to an embodiment of the present invention, the at least one gel pig <NUM> includes;.

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

Some examples of the sealant compositions are provided in the following examples.

The natural fibers may comprise fibers of a plant, animal, mineral, petrochemical origin and combinations thereof.

The fibers collected from the seeds of various plants are known as seed fibers. Fibers collected from the cells of a leaf are known as leaf fibers, such as ex. -pina, banana, etc..

Bast fibers are collected from the outer cell layers of the plant's stem. These fibers are used for durable yarn, fabric, packaging, and paper. Some non-limiting examples are flax, jute, kenaf, industrial hemp, ramie, rattan and vine fibers.

Fibers may be collected from the fruit of the plant, e.g. coconut fiber (coir) from the stalks of plants, e.g. straws of wheat, rice, barley, bamboo and straw.

Plant fibers are often rich in cellulose and they are a cheap, easily renewable source of fibers with the potential for polymer reinforcement. The presence of surface impurities and the large amount of hydroxyl groups make plant fibers less attractive for reinforcement of polymeric materials. Hemp, sisal, jute, and kapok fibers may be subjected to alkalization by using sodium hydroxide.

The nanofibers are bundles of cellulose fibers of widths, typically ranging between <NUM> and <NUM> and estimated lengths of several micrometers. The chemical analysis showed that selective chemical treatments increased the α-cellulose content of hemp nanofibers from <NUM> to <NUM>%.

Natural fibers may include one or more of hemp, jute, flax cotton, soft wood, Ramie, Sisal and Bamboo.

Typically, the natural fibers are received as a long yarn. The long yarn may be one-ply, two-ply, three-ply, four-ply or any number of ply or combinations thereof. The long yarns are cut in a cutting step to be of easily manageable dimensions. For example, they may be prepared to be <NUM> and <NUM>-ply. The cut fibers may be stored in a storing step before use.

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>, <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 hemp fibers may be, for example, the following types: NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply), NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply), NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply) and NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply) <NUM>% hemp long fiber yarn ringspun/bleached. eco-friendly, anti-bacteria, anti-UV and moisture-absorbent.

The yarns may be provided on spools or in packages and may be single-ply, <NUM>-ply, <NUM>-ply, <NUM>-ply, <NUM>-ply, <NUM>-ply, <NUM>-ply and <NUM>-ply or combinations thereof. In some cases, the following types are used: NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply), NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply), NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply) and NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply) long fiber yarn ringspun/OE bleached, eco-friendly, anti-bacterial, anti-UV and moisture-absorbent <NUM>% hemp.

According to other embodiments, the fibers may be selected from of a plant, animal, mineral, petrochemical origin and combinations thereof.

The fibers collected from the seeds of various plants are known as seed fibers. Fibers may be collected from the cells of a leaf, which are known as leaf fibers, such as ex. -pina, banana, etc..

Bast fibers are collected from the outer cell layers of the plant's stem. These fibers are used for durable yarn, fabric, packaging, and paper. Some examples are flax, jute, kenaf, industrial hemp, ramie, rattan and vine fibers.

Fibers collected from the fruit of the plant, e.g. coconut fiber (coir) from the stalks of plants, e.g. straws of wheat, rice, barley, bamboo and straw.

Plant fibers are rich in cellulose and they are a cheap, easily renewable source of fibers with the potential for polymer reinforcement. The presence of surface impurities and the large amount of hydroxyl groups make plant fibers less attractive for reinforcement of polymeric materials. Hemp, sisal, jute, and kapok fibers may be subjected to alkalization by using sodium hydroxide (Mwaikambo et al.

The nanofibers are bundles of cellulose fibers of widths ranging between <NUM> and <NUM> and estimated lengths of several micrometers. The chemical analysis showed that selective chemical treatments increased the α-cellulose content of hemp nanofibers from <NUM> to <NUM>% (Wang et al.

Bogoeva-Gaceva et al. , <NUM> compare the natural properties of various natural fibers, such as hemp, jute, flax cotton, soft wood, Ramie, Sisal and Bamboo. Typical properties include density, elongation at break, fracture stress and Young's modulus.

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

A non-limiting example of a gel-pig(s) composition <NUM> is:.

The fibers are wound fibers, yarns or combinations thereof.

<FIG> shows a simplified pictorial illustration showing another system <NUM> for sealing a pipeline, in accordance with an embodiment of the present invention. System <NUM> comprises two gel pigs <NUM>, <NUM>. These gel pigs may be of identical or different compositions. These are termed herein a rear gel pig <NUM> and a front gel pig <NUM>. Dispersed between the two gel pigs is fiber-in-sealant-in-carrier fluid (FISIC) composition <NUM>. Some non-limiting examples of the fiber-in-liquid (FISIC) compositions appear in the examples hereinbelow and are further described with respect to <FIG>.

There can be seen in <FIG> a simplified pictorial illustration showing another system <NUM> for sealing a pipeline, in accordance with an embodiment of the present invention. System <NUM> comprises three gel pigs <NUM>, <NUM>, <NUM> and two FISIC compositions <NUM>, <NUM>. These gel pigs may be of identical or different compositions. Likewise, FISIC compositions <NUM>, <NUM> may be identical or different. Some non-limiting examples of the gel pig compositions appear in the examples hereinbelow and with respect to <FIG> hereinbelow.

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

<FIG> is a simplified pictorial illustration showing another system <NUM> for sealing a pipeline, in accordance with an embodiment of the present invention. System <NUM> comprises two gel pigs <NUM>, <NUM> and a FISIC composition <NUM> or <NUM> disposed therebetween. The front gel pig <NUM> may be similar or identical to those described herein. The rear gel pig <NUM> comprises at least two or three different compositions <NUM>, <NUM>, <NUM>, for introduction into a pipeline sequentially (first <NUM>, then <NUM> and thereafter <NUM>).

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

Additionally or alternatively, the rear gel pig comprises four compositions, five compositions, six compositions, seven compositions, eight compositions or another multiplicity of compositions. A fourth composition <NUM> (not shown), a fifth composition <NUM> (not shown), a sixth composition <NUM> (not shown).

When six compositions are applied the first composition (front to back) serves as a separator between the sealing composition and the second composition. It has a density of <NUM>-<NUM>/cm<NUM>. The second composition, together with the third composition, forms a two (horizontal) layer sealant body preventing the bypass of the liquid propellant. The second composition has a density of <NUM>-<NUM>/cm<NUM> and the third composition has a density of <NUM>-<NUM>/cm<NUM>. The fourth and fifth compositions isolate the third composition from the propelling liquid. Respective densities are <NUM>-<NUM>/cm<NUM> and <NUM>-<NUM>/cm<NUM>. The sixth composition is a gel sealant, whose purpose is to temporarily seal the pig train from the rear upon launch. It has a density of <NUM>-<NUM>/cm<NUM>.

Reference is now made to <FIG>, which is a simplified flow chart of a method <NUM> for sealing a pipeline, in accordance with an embodiment of the present invention, with reference to <FIG>. A sealant composition, such as FISIC composition <NUM> is introduced to pipeline <NUM> in a (FISIC) composition introducing step <NUM>. This may be performed from one end of the pipe or from a manhole or vertical.

Thereafter, gel pig <NUM> is introduced from the same end of the pipe as the sealant composition or from a manhole or vertical, in a gel pig composition introducing step <NUM>.

The combination of the FISIC composition <NUM> and gel pig <NUM> is termed herein a "pig train". The pig train travels along the pipe in a travelling step <NUM> to site <NUM> of the leakage. The sealant composition within the FISIC operative to seal the leakage in a sealing step <NUM>. It typically takes a few minutes to several hours until the seal is fully cured.

Typically, gel pig <NUM> is of approximately the same diameter as the inner diameter of the pipe and is typically <NUM>-<NUM> diameters in length. The physical properties of the gel pig appear in Table <NUM>.

The pipeline may comprise one or more pipes or mains pipes, one or more laterals and one or more secondary laterals. The pipeline is shown as a straight pipe for the sake of simplicity and should not be deemed as limiting. The pipeline may further comprise valves, meters, joints, welds etc. These are not shown for the sake of simplicity.

Reference is now made to <FIG>, which is a simplified flow chart of another method <NUM> for sealing a pipeline, in accordance with an embodiment of the present invention, with reference to <FIG>.

A first gel pig <NUM> is introduced to the pipe in an optional introducing pig step <NUM>. The fiber-in-liquid pig may be introduced from a fire hydrant, from a manhole, vertical, lateral pipe, communications pipe or from a branch pipe.

A fiber-in-sealant-in carrier fluid (FISIC) composition, such as FISIC composition <NUM> is introduced to pipeline <NUM>, from a fire hydrant, from a manhole, vertical, lateral pipe, communication pipe or from a branch pipe, in a FISIC composition introducing step <NUM>. This may be performed from one end of the pipe or from a manhole or vertical.

Thereafter, a second gel pig <NUM> is introduced from the same end of the pipe, from a fire hydrant, from a manhole, vertical, lateral pipe, communication pipe or from a branch pipe, as the FISIC composition or from a manhole or vertical, in a second gel pig composition introducing step <NUM>.

The combination of the FISIC composition <NUM> and gel pigs <NUM>, <NUM> is termed herein a "pig train". The pig train travels along the pipe in a travelling step <NUM> to site <NUM> of the leakage. The sealant composition in the FISIC is operative to seal the leakage in a sealing step <NUM>. It typically takes a few minutes to several hours until the seal is fully cured.

Typically, gel pigs <NUM>, <NUM> are of approximately the same diameter as the inner diameter of the pipe and is typically <NUM> -<NUM> diameters in length. The physical properties of the front gel pig <NUM> appear in Table <NUM>.

The pig train is typically recovered from the pipeline in an exit pipe step <NUM>.

<FIG> is a simplified flow chart of another method <NUM> for sealing a pipeline, in accordance with an embodiment of the present invention, with reference to <FIG>.

A first gel pig <NUM> is introduced to the pipe in an optional first introducing pig step <NUM>. The first gel pig <NUM> may be introduced from a fire hydrant, from a manhole, vertical, lateral pipe, communication pipe or from a branch pipe.

A FISIC composition <NUM> is introduced to pipeline <NUM> in a first sealant composition introducing step <NUM>. This may be performed from one end of the pipe or from a manhole from a fire hydrant, lateral pipe, communication pipe or from a branch pipe or vertical.

Thereafter, a second gel pig <NUM> is introduced from the same end of the pipe as the first FISIC composition or from a fire hydrant, from a manhole, vertical, lateral pipe, communication pipe or from a manhole or vertical, in a second gel pig composition introducing step <NUM>.

A second FISIC composition <NUM> is introduced to pipeline <NUM> from a fire hydrant, from a manhole, vertical, lateral pipe, communication pipe or from a branch pipe in a second FISIC composition introducing step <NUM>. This may be performed from one end of the pipe or from a manhole or vertical.

Thereafter, a third gel pig <NUM> is introduced from the same end of the pipe as the first and second FISIC composition from a fire hydrant, from a manhole, vertical, lateral pipe, communication pipe or from a branch or from a manhole or vertical, in a third gel pig composition introducing step <NUM>.

The combination of the FISIC compositions <NUM>, <NUM> and gel pigs <NUM>, <NUM> and <NUM> is termed herein a "pig train". The pig train travels along the pipe in a travelling step <NUM> to site <NUM> of the leakage. The FISIC composition(s) is/are operative to seal the leakage in a sealing step <NUM>. It typically takes a few minutes to several hours until the seal is fully cured.

Typically, gel pigs <NUM>, <NUM>, <NUM> are of approximately the same diameter as the inner diameter of the pipe and is typically <NUM> -<NUM> diameters in length. The physical properties of the front/middle gel pig <NUM>/<NUM> appear in Table <NUM>.

The pig train is typically recovered from the pipeline in an exit pipe step <NUM>. In some cases, one or more of the gel pigs may be replaced with a polymer pig, such as polyurethane.

System <NUM> comprises an optional front gel pig <NUM> and at least one real gel pig <NUM>. A FISIC composition <NUM> is disposed between pigs <NUM> and <NUM>, forming a pig train <NUM>. A fluid <NUM> is inserted into a pipeline <NUM>, from a fire hydrant, from a manhole, vertical, lateral pipe, communication pipe or from a branch pipe, and a first pressure P<NUM> <NUM> is applied to fluid <NUM>. Additionally a second counter-pressure P<NUM>, <NUM> is applied to a second fluid <NUM>. Typically P<NUM> is much greater than P<NUM>. The average velocity of pig train <NUM> is determined by the fluid properties and a pressure difference (P<NUM>-P<NUM>). In some cases, front gel pig is not present.

Pressure P1 is introduced by a pump <NUM>, pressure from an existing network or any other suitable pressure introducing means, known in the art. The pressure P1 is typically regulated by control means, as are known in the art.

Pressure P2 may be introduced by any suitable passive means, such as a pressure relief valve <NUM>, a discharge valve, a pressure regulator or the like.

The gel pigs of the present invention provide the following advantages: -.

In this example, the values percent of the compositions A and B per <FIG> hereinbelow, and exemplary weight concentration ranges are provided.

These materials once cured serve to provide robust long term plugging of the leakage with a longevity of similar order of magnitude to the remaining useful life of the host pipe. They also serve to withstand changing environmental conditions. The cured product having a similar thermal coefficient in order of magnitude to the host pipe typically expands and contracts under changing temperatures in unison with the host pipe so as not to create a secondary leak under these conditions.

This example shows the composition of the sealant plug covering the hole in the pipe and the pipe remains in the field of repair of.

A gel pig is formed according to the following method.

The front and/or rear gel pigs may comprise any combination of components as appear in Tables 1A-1C hereinbelow.

Another non-limiting example of composition of a gel pig is in accordance with the composition in table 1C below:.

According to some embodiments, the physical properties of the gel pigs appear as in tables <NUM> and/or <NUM>.

According to one or more embodiments, hydrophobic solvents are liquid oils originating from synthetic, vegetable, marine or animal sources. The canola oil exemplified may be replaced by any suitable liquid oil including saturated, unsaturated or polyunsaturated oils. By way of example, the unsaturated oil may be olive oil, corn oil, soybean oil, cottonseed oil, coconut oil, sesame oil, sunflower oil, borage seed oil, syzigium aromaticum oil, hempseed oil, herring oil, cod-liver oil, salmon oil, flaxseed oil, wheat germ oil, canola oil, evening primrose oils or mixtures thereof, in any proportion.

According to one or more embodiments, the silica exemplified may be replaced by a) microsponges, b) silica, c) mineral bodies like zeolite, bentonite, (iii) graphite, including polymers, dendrimers and liposomes, or mixtures thereof, in any proportion.

According to one or more embodiments, the aluminum hydroxide exemplified may be replaced by minerals such as aluminum phosphate and calcium phosphate or mixtures thereof, in any proportion.

According to one or more embodiments, the hydroxyethyl cellulose exemplified may be replaced by any at least one polymeric additive selected from the group consisting of polysaccharides, natural polysaccharides, derivatives thereof, modified poysaccharides, derivatives thereof, starch, dextrin, glycogen, cellulose and chitin, glycosaminoglycans (GAG's), chondroitin sulphate, dermatan sulphate, keratan sulphate, heparan sulphate, heparin, and hyaluronan, amylose and amylopectin, cellulose derivatives, xanthan gum, sodium CMC, methylcellulose, and hydroxyl propyl methyl cellulose or mixtures thereof, in any proportion.

Specific non limiting examples of surfactants are an ionic surfactant, a nonionic surfactant, a hydrophobic surfactant or mixtures thereof, in any proportion.

Exemplary hygroscopic agents that can be used in accordance with one or more embodiments include, for example, naturally-occurring polymeric materials, such as locust bean gum, sodium alginate, sodium caseinate, egg albumin, gelatin agar, carrageenan gum, sodium alginate, xanthan gum, quince seed extract, tragacanth gum, guar gum, starch, chemically modified starches and the like, semi-synthetic polymeric materials such as cellulose ethers (e.g. hydroxyethyl cellulose, methyl cellulose, carboxymethyl cellulose, hydroxy propylmethyl cellulose), guar gum, hydroxypropyl guar gum, soluble starch, cationic celluloses, cationic guars, and the like, and synthetic polymeric materials, such as carboxyvinyl polymers, polyvinylpyrrolidone, polyvinyl alcohol, polyacrylic acid polymers, polymethacrylic acid polymers, polyvinyl acetate polymers, polyvinyl chloride polymers, polyvinylidene chloride polymers and the like. Mixtures of the above compounds are contemplated.

According to some further embodiments, a base may be selected from sodium hydroxide, magnesium hydroxide, aluminum hydroxide, potassium hydroxide and combinations thereof.

Reference is now made to <FIG>, which is a simplified pictorial illustration of a fiber <NUM> before and after <NUM> being soaked in a liquid <NUM>, in accordance with an embodiment of the present invention.

<FIG> is a simplified pictorial illustration of a three dimensional structure <NUM> of fibers <NUM>, <NUM> trapping a liquid <NUM>, in accordance with an embodiment of the present invention.

Reference is now made to <FIG>, which shows a simplified flowchart <NUM> of a method for the preparation of a FISIC composition <NUM> in accordance with an embodiment of the present invention.

One or more natural fibers <NUM> are cut in a cutting step <NUM>.

For example, the hemp fiber used may comprise one or more of the following: NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply), NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply), NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply) and NM8. <NUM>/<NUM> (count <NUM> with <NUM> ply) <NUM>% hemp long fiber yarn ringspun/OE bleached or non-bleached, eco-friendly, anti-bacteria, anti-UV and moisture-absorbent.

Fibers collected from the fruit of the plant, e.g. coconut fiber (coir) bers from the stalks of plants, e.g. straws of wheat, rice, barley, bamboo and straw.

Plant fibers are rich in cellulose and they are a cheap, easily renewable source of fibers with the potential for polymer reinforcement. The presence of surface impurities and the large amount of hydroxyl groups make plant fibers less attractive for reinforcement of polymeric materials. Hemp, sisal, jute, and kapok fibers were subjected to alkalization by using sodium hydroxide.

The nanofibers are bundles of cellulose fibers of widths ranging between <NUM> and <NUM> and estimated lengths of several micrometers. The chemical analysis showed that selective chemical treatments increased the α-cellulose content of hemp nanofibers from <NUM> to <NUM>%.

Typically, the natural fibers <NUM> are received as a long yarn. The long yarn may be one-ply, two-ply, three-ply, four-ply or any number of ply or combinations thereof. The long yarn is cut in a cutting step <NUM> to be of easily manageable dimensions, for example, <NUM> and <NUM>-ply. The cut fibers <NUM> may be stored in a storing step <NUM> before use.

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>, <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, <NUM>-ply, <NUM>-ply and <NUM>-ply or combinations thereof.

According to some embodiments of the present invention, composition A comprises hardener (<NPL>, Bisphenol A <NUM>-<NUM>-<NUM>, Isophorondiamine <NUM>-<NUM>-<NUM>, and Benzyl alcohol <NUM>-<NUM>-<NUM>)-see tables <NUM> and <NUM>.

According to some embodiments of the present invention, composition B comprises Epoxy resin (<NUM>-<NUM>-<NUM> Phenol-Formaldehyde Polymer Glycidyl Ether and <NUM>-<NUM>-<NUM> Alkyl (C12-C14) glycidyl ether) and acts as a resinous composition.

According to some embodiments of the present invention, first composition A and a second composition B are mixed in a first mixing step <NUM>.

In another embodiment of the present invention, the formulation of composition A appears in table <NUM>.

According to some embodiments of the present invention, composition B (see tables <NUM>-<NUM>) comprises Epoxy resin (comprising, for example, <NUM>-<NUM>-<NUM> Phenol-Formaldehyde Polymer Glycidyl Ether and <NUM>-<NUM>-<NUM> Alkyl (C12-C14) glycidyl ether) and acts as a resinous composition.

In another embodiment of the present invention, the formulation of composition B appears in table <NUM>.

The cut fibers <NUM> are mixed with mix <NUM><NUM> in a third mixing step <NUM> to form a third mix <NUM>. This is the fiber-in-sealant composition.

A non-limiting example of the carrier fluid composition appears in Table <NUM> hereinbelow.

Another non-limiting example of a carrier fluid composition <NUM> is provided in Table <NUM> hereinbelow.

In some cases, the vegetable oil may be replaced in part or fully by silicone oil, a synthetic oil, one or more fatty acids, a surfactant, a non-vegetable oil or combinations thereof.

In another embodiment of the present invention, a non-limiting example of mix <NUM>, <NUM> appears in table <NUM> hereinbelow.

In another embodiment of the present invention, a non-limiting example of mix <NUM> (fiber-in-sealant composition), <NUM> appears in table <NUM> hereinbelow.

A non-limiting example of the fiber-in-sealant-in-carrier fluid (FISIC) composition appears in Table <NUM> herein below.

The ratio of A to B ratio is typically between <NUM>:<NUM> to <NUM>:<NUM>, between <NUM>:<NUM> to <NUM>:<NUM>, between <NUM>:<NUM> to <NUM>:<NUM>, between <NUM>:<NUM> to <NUM>:<NUM>. In one embodiment the ratio of A:B is <NUM>:<NUM> i.e. <NUM> parts of A to <NUM> parts of B. A and B are as defined herein. The resultant first mix <NUM> is then mixed in a second mixing step <NUM> with a silica formulation <NUM>.

In a second mixing step <NUM>, ground silica formulation <NUM> (comprising cristobalite (<NPL>), Aluminum oxide <NPL>, Iron(III) oxide <NUM>-<NUM>-<NUM> and Titanium(IV) oxide, anatase <NUM>-<NUM>-<NUM>) is mixed with first mix <NUM> to form a second mix <NUM>. Typically, the ratio of silica formulation <NUM> to first mix <NUM> is <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM> or <NUM>:<NUM>. Preferably the ratio is between <NUM>:<NUM> to <NUM>:<NUM>. The second mix <NUM> is mixed with cut fibers <NUM> to form a third mix <NUM> in a third mixing step <NUM>. Typically, the ratio of cut fibers <NUM> to second mix <NUM> is <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM> or <NUM>:<NUM>. Preferably the ratio is between <NUM>:<NUM> to <NUM>:<NUM>. A carrier fluid <NUM>, as exemplified in Tables <NUM>-<NUM> is introduced and mixed with third mix <NUM> in a fourth mixing step <NUM>. Typically, the ratio of third mix <NUM> to carrier formulation <NUM> is <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM>, <NUM>:<NUM> or <NUM>:<NUM>. Preferably the ratio is between <NUM>:<NUM> to <NUM>:<NUM>. A non-limiting example of a carrier fluid composition <NUM> is provided in Table <NUM> hereinbelow.

A final FISIC composition comprising fibers <NUM>, is then ready for use.

In this example, the values percent of compositions A and B, and exemplary weight concentration ranges are disclosed.

This example shows the composition of the sealant plug covering the hole in the pipe and the pipe remains in the field of repair of pipelines.

Reference is now made to <FIG>, which is a simplified pictorial illustration of a multi-ply fiber <NUM>, in accordance with an embodiment of the present invention. The fiber may comprise <NUM>-<NUM> plies, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or more, for example.

<FIG> is a simplified pictorial illustration <NUM> of a FISEC-sealed leak <NUM> in a cast-iron pipe <NUM>, in accordance with an embodiment of the present invention.

In pipes <NUM> such as cast iron, asbestos cement, PVC, etc. that leak due to defects in the watertight joints, the fibers-in-sealant <NUM> provides the necessary caulking mechanism to reseal the leak. The fibers-in-sealant are introduced into the leaky joint area by the leak flow forming a solid seal between the pipe and one or more outer casings <NUM>, <NUM>.

<FIG> is a simplified pictorial illustration <NUM> of a longitudinal defect <NUM> in a plastic pipe <NUM>, in accordance with an embodiment of the present invention.

<FIG> a simplified pictorial illustration <NUM> of a fiber-in-sealant cure <NUM> within an inner surface <NUM> of the longitudinal defect <NUM> in the plastic pipe <NUM> of <FIG>, in accordance with an embodiment of the present invention.

In plastic pipes such as HDPE, MDPE, PVC etc., longitudinal defects, such as cracks <NUM> may form from exposure to freezing temperatures, over-pressurization or defects in the manufacturing or pipelaying process (<FIG>). The fibers-in-sealant are introduced into leaky cracks by the leak flow forming a solid seal <NUM> from within (<FIG>) on the inner surface. The curing of the sealant provides for long term longevity of the seals to prolong the serviceability of the pipe.

It should be understood that all the flowcharts and methods herein may be repeated in part or fully to seal a number of leakages. Moreover, in some cases the methods or parts thereof may be repeated to improve the sealant and/or curing properties of the seal and/or cure to properly seal one or more pipelines. The flowcharts are simplified herein, for the purpose of explaining the invention, and should not be deemed limiting.

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

Claim 1:
A system (<NUM>, <NUM>, <NUM>, <NUM>) for curing at one leakage site (<NUM>) in a pipeline (<NUM>, <NUM>), the system (<NUM>, <NUM>, <NUM>, <NUM>) comprising:
a) at least one gel pig (<NUM>, <NUM>, <NUM>); and
b) at least one fibers-in-sealant-in carrier fluid (FISIC) composition (<NUM>, <NUM>), also called FISIC composition, wherein said fibers in at least one form selected from the group consisting of: wound fibers, yarns and combinations thereof; and wherein said at least one gel pig (<NUM>, <NUM>, <NUM>) and said at least one FISIC composition (<NUM>, <NUM>) form a pig train, adapted to move along said pipeline (<NUM>, <NUM>) to a region of said at least one leakage (<NUM>) and to seal and cure said at least one leakage (<NUM>).