KR100775634B1 - Non-excavating repair materials of a pipe and repair method using the same - Google Patents

Abstract

A non-excavating repair member for a conduit and a method of repairing the conduit using the repairing member are provided to fix the damaged conduit regardless of stepped or irregular surfaces on inner walls of the conduit by winding a sleeve of the repair member into a contracted cylindrical shape and inserting the sleeve into the damaged conduit. Sleeve is unwound inside the conduit and corrugated grooves and protrusions on outer circumference of the sleeve allow the sleeve to be flexible and maintain a gap between the sleeve and the inner walls of the conduit, maintaining enough room for the sleeve to inject repairing agent through injection ports disposed on o-rings fitted on outer circumference of the sleeve. In a non-excavating repair member wound into a cylindrical shape and inserted into a conduit(P) and then unwound in the conduit to repair the damaged section of the conduit, the repair member includes a sleeve(110) wound into a cylindrical shape and capable of unwinding back to original shape with the elastic force. The sleeve has plural corrugation grooves(111) on an outer circumference. O-rings(120) are installed on two ends and on middle section of the sleeve respectively to seal outer surface of the sleeve and inner walls of the conduit, and to provide insertion ports(115) for injecting repairing agent into outer surface of the sleeve and on inner walls of the conduit respectively. An elastic band is wrapped around the outer circumference of the sleeve. Plural protrusions(131) are disposed along the outer surface of elastic bands with regular intervals between the protrusions for maintaining a gap between the outer surface of the sleeve and the inner walls of the conduit. Contraction prevention units prevent the sleeve from contracting back once the sleeve is unwound. The protrusions on the elastic bands and the corrugation grooves allow the sleeve to maintain preset gap between the outer surfaces of the sleeve and stepped part or irregular surfaces on inner walls of the conduit.

Description

NON-EXCAVATING REPAIR MATERIALS OF A PIPE AND REPAIR METHOD USING THE SAME}

1 is a perspective view of a repair member according to the present invention.

Figure 2 is an exploded perspective view of a part of the repair member according to the present invention.

Figure 3 is a partially exploded perspective view showing a part of the repair member according to the present invention.

Figure 4 is a cross-sectional view of the repair member according to the present invention.

5 is a flow chart for explaining the repair method of the present invention.

6 to 12 are a series of reference diagrams for explaining the repair method of the present invention.

* Description of the symbols for the main parts of the drawings *

110: sleeve 111: corrugated bone

120: siling O-ring 131: spacing projection

133: band 140: guide belt

141: latch hole 143: latch

The present invention relates to a pipeline repair method, and since it can be easily repaired even at the site where the stepped connection part of the pipeline and the inner wall are irregular in shape, the non-excavated pipeline repair capable of high quality repair over the entire pipeline section The present invention relates to a member and a pipeline repair method using the same.

In general, the non-excavation repair method refers to a method for repairing abnormal parts in case of various problems that may cause leaks such as partially ruptured pipes, open joints, or steps.

In this repair method, the whole repair method is repaired by inserting the synthetic resin tube into the abnormal part as a whole. The adhesive resin solution is applied to the glass fiber using only the adhesive resin solution and the glass fiber to impregnate the glass fiber to be impregnated, and then partially cured. Lining method for repairing, and a reinforcing ring method for installing a non-excavation repair member of stainless steel configured to be wound in a cylindrical shape in close contact with the pipe.

Among the above methods, the lining method can relatively clean the damage and cracks of the pipe which caused the leakage compared to other methods, and the inside of the pipe is smooth after construction, which does not interfere with the flow of sewage. It has been widely used.

However, the lining method was structurally very weak because the lining material coated on the inner wall of the pipeline is liquid or soft and must secure itself so as not to fall off until it is cured. Therefore, this caused various problems.

First, the process of coating lining material on the inner wall of the pipeline was quite difficult and complicated, which required expensive equipment and required a lot of construction time.

Second, since the lining material has to be thickly coated to secure the coating strength, the amount of lining material used is large, increasing the construction cost and reducing the diameter. In addition, the curing time of the lining material was considerably taken.

Third, even when the lining material is thickly coated, the structural rigidity is still weak and cracks are generated during the curing of the coated lining material.

Fourth, even after the lining material was cured, the coated lining material was always exposed to the risk of easily falling off the inner wall of the pipeline.

Therefore, in order to solve the problems caused by the lining method, recently, in addition to the adhesive resin and the glass fiber, a stainless steel sheet configured to be wound in a cylindrical shape inside the repairing material is used as a reinforcing support tube. Lining partial repair method is used.

Improved lining partial repair method has the advantages of being able to cover the lining material thinner compared to the existing lining method, work process is relatively simple, secure structural rigidity, etc. I was able to solve a large part.

However, the stainless steel sheet used in the improved lining partial repair method had to be provided with high strength because it had to support all loads by itself without any help from the lining material without self-supporting force. In particular, when repairing medium and large pipes, such as a collecting pipe, a stainless steel sheet having a higher strength had to be provided. Therefore, due to the high strength of the stainless steel sheet, it is possible to hardly work in the partly curved section of the pipeline, the stepped connection section, or the irregular shape of the inner wall, or another problem that can not expect good quality work performance. .

Therefore, the present invention has been proposed to solve the conventional problems as described above, the object of the present invention is easy to repair even in the irregular section of the stepped connection portion or the inner wall of the non-excavation can obtain a high quality repair results It is to provide the pipeline repair member and repair method.

In order to achieve the object as described above, the non-excavated pipeline repair member according to the technical idea of the present invention is inserted into the pipeline in a contracted state in a cylindrical shape and then expanded and then damaged and cracked. In the non-excavation repair member, a sleeve having an elastic force to be released to its original state when it is wound in a cylindrical shape, and having a plurality of corrugated bones formed in the circumferential direction on the outer side, and are respectively provided on the outer side surfaces of both ends of the sleeve. Sealing O-rings at both ends of the sleeve to seal between the outer side of the sleeve and the inner wall of the conduit, and at the intermediate portion between the both ends of the sleeve to provide a space for injecting strength and water reinforcement medicine between the outer side of the sleeve and the inner wall of the conduit. And protruded from an outer surface of the sleeve of the intermediate portion, between the outer surface of the sleeve and the inner wall of the conduit. That comprises a plurality of spacing projections for, shrinkage preventing means for restraining to prevent shrinkage after the expansion the sleeve is to keep the price may be characterized on the technical configuration.

Here, the plurality of gap maintaining projections may be coupled to the outer surface of the band provided to surround the outer surface of the sleeve in the circumferential direction at a predetermined interval.

In addition, the shrinkage preventing means, is provided in the circumferential direction on the outer surface of the sleeve comprises a guide belt for guiding to slide the one end of the sleeve, one end of the sleeve is cut through the guide belt penetrating portion It is formed, the guide belt may be characterized in that only the two ends are joined to the outer surface of the sleeve, a sliding section in which one end of the sleeve is guided and slide between the joined both ends.

In addition, the guide belt is provided with a plurality of engaging holes formed along the longitudinal direction, and is bent after extending from one end of the guide belt, when the sleeve is inflated and then contracted from the outside of the guide belt when the contraction hole It may be characterized in that it has a latch for preventing the shrinkage of the sleeve while being caught.

On the other hand, the repair method of the present invention comprises the steps of winding a thin plate-like sleeve having an elastic restoring force in a cylindrical state and shrinking against the elastic force, and installing the sealing O-rings on the outer surfaces of both ends of the sleeve in the wound state; And installing a plurality of spacing projections on the outer side of the sleeve, and expanding the sleeve by inserting the sleeve into a damaged and / or cracked conduit in a contracted state and winding the sleeve. It may be characterized by the technical configuration that comprises the step of injecting and curing the strength and index reinforcing agent between the inner wall.

Here, the plurality of gap holding projections may be coupled to the band provided to surround the outer surface of the sleeve in the circumferential direction at regular intervals in the longitudinal direction thereof.

In addition, any one of the sleeve and the sealing O-ring may be characterized in that the medicine injection hole and the air discharge hole for the discharge of the air when the injection of the medicine is provided.

In addition, the outer surface of the sleeve is configured to include a guide belt for circumferentially guiding one end of the sleeve to slide, one end of the sleeve is formed with a cut through the guide belt is formed, the guide belt It is characterized in that both ends are joined to the outer surface of the sleeve, a sliding section in which one end of the sleeve is guided and slides between the joined ends.

In addition, the guide belt is provided with a plurality of engaging holes formed along the longitudinal direction, and is bent after extending from one end of the guide belt, when the sleeve is inflated and then contracted from the outside of the guide belt when the contraction hole It may be characterized in that it has a latch for preventing the shrinkage of the sleeve while being caught.

In addition, the sleeve may be characterized in that it has a plurality of corrugated bone formed in the circumferential direction on the outer surface.

In addition, the medicine may be characterized in that the polyester or polyurethane.

In addition, the sleeve may be characterized in that continuously installed in the pipeline.

Hereinafter, embodiments of the present invention as described above will be described in detail with reference to the accompanying drawings.

EXAMPLE

1 is a perspective view of a repair member according to the present invention, Figure 2 is an exploded perspective view of a part of the repair member according to the present invention, Figure 3 is a partially exploded perspective view showing a part of the repair member according to the present invention. 4 is a cross-sectional view of the repair member according to the present invention.

As shown, the repair member 100 of the present invention is a sleeve 110 having a plurality of corrugated bone 111, a pair of sealing O-ring 120, and a plurality of gap maintaining projections 131 And, it comprises a guide belt 140, which is a shrinkage preventing means.

Repair member 100 of the present invention is appropriate between the inner wall and the sleeve 110 in the irregular section, such as the stepped portion in the pipeline centered on the corrugated bone 111 and the gap maintaining projection 131 of the sleeve 110. It is configured to keep the interval evenly, which ensures higher quality maintenance and reliable index status when injecting medicine.

The sleeve 110 has an elastic force that tends to be released as it is when it is wound in a cylindrical shape, and is made of a material excellent in corrosion resistance and corrosion resistance. Any material having the above characteristics as the material of the sleeve 110 may be adopted, and stainless steel is suitable. The thickness of the sleeve 110 is formed as thin as possible so as to bend easily within the range that satisfies the conditions for easy contraction and expansion while having elastic force. This is because the repair member 100 of the present invention, unlike the conventional repair member 100, is to avoid the use of a simple lining material to support the support force, so that the use of the strength and exponential reinforcing agent in mind. Furthermore, the sleeve 110 has a plurality of corrugated bones 111 formed on the outer surface in the circumferential direction, so that the sleeve 110 can be easily curved without being rigid within a limited range. Therefore, it is easy to install regardless of the stepped connection part or the inner wall irregular section. The corrugated bone 111 of the sleeve 110 may be formed on the whole or part of the sleeve 110 as necessary, and can be easily formed on the sleeve 110 if a forming roller is used.

One end portion of the sleeve 110 is formed with an incision 113 through which the guide belt 140 penetrates so that the guide belt 140 can be guided during contraction and expansion.

The sealing O-ring 120 is installed on the outer surface of both ends of the sleeve 110, respectively. As a result, the sealing O-ring 120 is pressed between both ends of the sleeve 110 when the sleeve 110 is in close contact with the inner wall of the pipe, and seals between the outer surface of the sleeve 110 and the inner wall of the pipe. As a result, a gap space is provided between the outer surface of the sleeve 110 and the inner wall of the conduit at an intermediate portion located between both ends of the sleeve 110 to allow the injection of strength and exponential reinforcing medicine. In this case, the height of the gap space for injecting the medicine depends on the compressed thickness of the sealing O-ring 120. The sealing O-ring 120 has a medicine injection hole 115 for injecting the medicine to the gap space formed between the outer surface of the sleeve 110 and the inner wall of the pipe. In addition, it is provided with an air discharge hole 117 so that the air is discharged when the medicine is injected through the medicine injection hole 115. However, the medicine injection hole 115 and the air discharge hole 117 provided in the sealing O-ring 120 may be provided in the sleeve 110, and optionally provided in any one place. However, in the drawing (FIG. 2), for convenience of description, the medicine injection hole 115 and the air discharge hole 117 are illustrated as being provided in both the sealing O-ring 120 and the sleeve 110. But only in one place.

The gap maintaining protrusion 131 is installed in the form of a plurality of protrusions on the outer surface of the sleeve (110). To this end, an O-ring type rubber band 133 is provided to surround the outer surface of the sleeve 110 in the circumferential direction. And the gap maintenance projections 131 on the outer surface of the band 133 is coupled and fixed at a predetermined interval. As such, when the band 133 and the space keeping protrusion 131 are provided in an integrated form, it is very easy to install the space keeping protrusion 131 on the sleeve 110. The gap maintaining protrusion 131 is installed in one row along the band 133 at regular intervals, and the sleeve 110 is installed in a row along another band 133 provided separately. A plurality of rows are installed in a row. As a result, the gap between the outer surface of the sleeve 110 and the inner wall of the pipeline 110 may be uniformly maintained. That is, it is possible to make the height of the gap space for the injection of the strength and exponential reinforcing medicine. As such, if the interval between the outer surface of the sleeve 110 and the inner wall of the pipe is uniformly maintained throughout the sleeve 110, the thickness of the medicine that is injected and cured can be uniformized, thereby making it possible to repair the pipe of high quality.

The guide belt 140, which is the shrinkage preventing means, is installed in the circumferential direction on the outer side of the sleeve 110 (basically installed on the other end of the outer side of the sleeve 110 and installed from the other end to one end in its entirety). Can be). As a result, the guide belt 140 serves to guide one end of the sleeve 110 to slide along the outer surface of the sleeve 110 when the sleeve 110 is contracted and expanded in the wound state.

Looking at the configuration of the guide belt 140 in more detail, both ends of the guide belt 140 in the state passing through the cutout portion 113 formed in one end of the sleeve 110 of the sleeve 110 It is installed on the outer side in the circumferential direction. Thus, both ends of the guide belt 140 is bonded to the outer surface of the sleeve 110, but the non-bonded section between both ends is a sliding section (D) in which one end of the sleeve 110 is slid. Here, the guide belt 140 is a plurality of appropriately installed in accordance with the width width of the sleeve 110. The length of the guide belt 140 may be a little more than the distance that one end of the sleeve 110 moves during contraction and expansion of the sleeve 110. Due to the installation of the guide belt 140, when the sleeve 110 contracts and expands, one end of the sleeve 110 slides along its outer surface, thereby achieving a more stable contraction and expansion operation.

The guide belt 140 is provided with a plurality of engaging holes 141 formed along the longitudinal direction. The catching hole 141 is perforated in a rectangular shape. In addition, the guide belt 140 has a latch 141 formed by extending from one end of the guide belt 140 and being bent, and the latch 141 is contracted after the sleeve 110 is expanded. When it is restrained while being caught by the locking hole 141 from the outside of the guide belt 140 to prevent the shrinkage of the sleeve 110. The latch 143 is bent inward by 60 ° to 45 ° so that it can be caught only upon contraction.

Subsequently, the non-excavation pipeline repair method of the present invention using the non-excavation repair member 100 described above will be described.

5 is a flow chart for explaining the repair method of the present invention, Figures 6 to 12 is a series of reference diagrams for explaining the repair method of the present invention.

First, in order to install the repair member 100 in the conduit (P) in the repair method of the present invention, a body 10 is required to be stretchable. For reference, the repair device 10 may be used without limitation as long as it can be widely expanded after the repair member 100 of the present invention is placed inside the pipeline P requiring repair. However, for convenience, it will be described with the conservative 10 in the form of a tube in which the body 31 is expanded by air injection.

As such, when the repair device 10 is provided, the repair method of the present invention may refer to FIG. 5, as shown in FIG. 5, the contraction step of the repair member (S100), the installation step of the sealing O-ring (S200), the preparation step of the medicine injection hole and the air outlet hole (S300), the installation step of maintaining the gap (S400), the injection step in the pipeline of the repair member (S500), the expansion step of the repair member (S600), the injection step of the medicine (S700).

In the contraction step (S100) of the repair member, the thin plate-like sleeve 110 having an elastic restoring force is wound in a cylindrical shape and contracted against the elastic force. To this end, the sleeve 110 of the repair member 100 is covered with the body of the repairer 10 while the body of the repairer 10 is contracted. At this time, the sleeve 110 may have a tendency to be inflated, but is not inflated by the guide belt 140 installed at the outer surface thereof.

In the installation step (S200) of the sealing O-ring, the sealing O-rings 120 are respectively installed on outer surfaces of both ends of the sleeve 110 in a wound state. Since the sealing O-ring 120 is made of a rubber material, the sealing O-ring 120 may be slightly opened and simply covered on the outer surface of the sleeve 110. The sealing O-ring 120 helps the guide belt 140 to stably hold the sleeve 110 in a tendency to expand in a contracted state.

In the preparing step of the medicine injection hole and the air discharge hole (S300), by selectively drilling the sealing O-ring 120 or the sleeve 110 to provide a medicine injection hole 115 and the air discharge hole 117. . This step is preferably the first to proceed.

In the installation step (S400) of the spacing maintenance projections, a plurality of spacing maintenance projections 131 are installed on the outer surface of the sleeve 110. To this end, the gap maintaining protrusion 131 is coupled to the rubber band 133 provided to surround the outer surface of the sleeve 110 in the circumferential direction at regular intervals in the longitudinal direction thereof. And when the construction is in progress it is possible to simply install the gap holding projection 131 by covering the rubber band 133 on the outer surface of the sleeve 110. The gap maintaining protrusion 131 serves to uniformly maintain the distance between the outer surface of the sleeve 110 and the inner wall of the pipeline P evenly over the entire section of the sleeve 110.

In the conduit input step (S500) of the repair member, the repair device 10 and the repair member 100 mounted thereon in the contracted state of the body is inserted into the pipeline (P) as shown in FIG. Position it correctly in position. Thereafter, when the body of the water retainer 10 is expanded as shown in FIG. 7, the sleeve 110 is gradually expanded. In this process, one end of the sleeve 110 is slid from the outer surface of the sleeve 110 along the guide belt 140 penetrating the cutout 113 and gradually moves to the end thereof. Then, when the sleeve 110 gradually expands, the sleeve 110 is brought into close contact with the inner wall of the pipeline P. In this case, the sealing O-ring 120 installed on the outer surface of the sleeve 110 is compressed between the sleeve 110 and the inner wall of the conduit P, and the sealed gap for injecting medicine to the intermediate point between both sides of the sleeve 110 is sealed. Provide a space S. As such, the expanded state of the sleeve 110 is illustrated in FIG. 8.

Referring to FIG. 8, in the state in which the sleeve 110 is expanded in the conduit P, the outer surface of the sleeve 110 and the conduit P are formed by a sealing O-ring 120 installed on the outer surface of the sleeve 110. A gap space (S) for injecting medicine is provided without being completely adhered between the inner walls. At this time, although the inner wall of the pipe (P) is stepped, the sleeve 110 is naturally curved by the corrugated bone 111, and for the gap maintaining protrusion 131 installed on the outer surface of the sleeve 110 The gap space (S) for injecting medicine is formed at a uniform height in the whole range. In addition, the sleeve 110 is provided with a thinner thickness in consideration of the strength and exponential reinforcing medicine (C) as described above. Thus, the sleeve 110 is naturally curved without great difficulty. If the conventional repair member 100 using a conventional lining material that can not be expected at all, if the strength is excluded, the thickness of the sleeve 110 is too thick when repairing a heavy pipe, such as a collecting pipe line none. Because of this, unlike the repair member 100 of the present invention can not be expected to bend itself.

In the injection step (S700) of the medicine, strength and index reinforcement between the outer surface of the sleeve 110 and the inner wall of the pipe (P) through the medicine injection hole 115 of the repair member 100 installed as shown in FIG. Inject medicine (C). At this time, while the medicine (C) is injected into the space (S) formed between the outer surface of the sleeve 110 and the inner wall of the pipe (P), the air filling the space (S) as shown by the arrow air discharge hole 117 Is discharged through). Subsequently, when the medicine is completely filled in the medicine injection space (S) as shown in FIG. 10, the injection of the medicine is stopped.

After the time has elapsed and the medicine C filled in the medicine injection space S is cured, the exponential property of the sleeve 110 due to the cured medicine C is wrapped in the outer surface of the sleeve 110. And support strength is further improved. Due to the strength reinforcement function of the strength and the exponential reinforcement (C) can be formed in the sleeve 110, the corrugated bone (111), which can cause a weakening of the strength, as well as in the step portion in the pipeline (P) It is possible to use a sleeve 110 of a thin material that is relatively weak in strength to be more flexible close contact. Here, the medicine (C) may be used for the index and strength reinforcement while surrounding the outer side of the repair member 100, it is suitable if the polyester (Polyester) or polyurethane (Polyurethan).

Thereafter, as shown in FIG. 11, the water retainer 10 is contracted by the body to be separated from the sleeve 110 and then removed out of the conduit P. Then, only the repair member 100 of the present invention remains in close contact with the inner wall surface of the pipeline (P). This is because the sleeve 110 has a tendency to shrink back to its original state when the body of the water retainer 10 is contracted, but the latch 143 formed in the guide belt 140 is caught and caught by the locking hole 141 to be inflated. This is because it is maintained.

On the other hand, Figure 12 shows that the water supply member 100 of the present invention continuously installed in the pipe (P). This can be achieved by repeating the partial repair method of the pipe line (P) described above, but continuously placing the sleeve 110 in the pipe line (P). At this time, the entire section of the conduit (P) can be repaired by a method of overlapping the adjacent end portions of the adjacent sleeves 110 to some extent.

Although the preferred embodiment of the present invention has been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

As described above, the non-excavated pipeline repairing member and the repairing method according to the present invention are provided between the sleeve and the inner wall of the pipeline even at the stepped connection portion of the pipeline requiring the repair by the gap maintenance protrusion or the irregular shape of the inner wall. The spacing can be kept uniform. Thereby, this invention can apply | coat a chemical | medical agent to uniform thickness.

In addition, the present invention can use a thinner and softer sleeve by using a strength and index reinforcing agent that can reinforce the bearing capacity of the sleeve. Therefore, the sleeve can be bent naturally corresponding to the irregular inner wall of the pipe, such as the stepped portion of the pipe.

In addition, the present invention is to effect the natural bending of the sleeve by a plurality of corrugated bone provided in the sleeve to correspond to the irregular inner wall of the pipeline such as the step portion of the pipeline while maintaining a constant distance between the sleeve and the pipeline throughout the sleeve There is.

In addition, the present invention enables the high quality repair in all sections or partial sections of the pipeline by the above effects.

Claims (8)

In the non-excavation repair member of the pipeline is installed on the inner wall of the pipeline that is expanded and then broken and cracked after being inserted into the pipeline in a contracted state in a cylindrical shape, A sleeve having a plurality of corrugated bones formed in a circumferential direction on an outer surface thereof, having an elastic force to be released to its original state when wound in a cylindrical shape; It is installed on each of the outer surface of both ends of the sleeve to seal between the outer surface of the sleeve and the pipe inner wall at both ends of the sleeve, and in the intermediate portion between the both ends of the sleeve for strength and index reinforcement between the outer surface of the sleeve and the inner wall of the pipe O-ring for sealing to provide a space for injection of medicine; An elastic band provided around the outer surface of the sleeve in a circumferential direction; A plurality of gap maintaining protrusions installed on the outer side of the band at intervals along the longitudinal direction to maintain a gap between the outer side of the sleeve and the inner wall of the conduit; And a contraction preventing means for restraining the sleeve from expanding after the sleeve is inflated. delete Winding a thin plate-like sleeve having elastic restoring force into a cylindrical shape to shrink against elastic force; Installing sealing o-rings on outer surfaces of both ends of the sleeve in a wound state; Installing a plurality of spacing projections on an outer surface of the sleeve; Winding the sleeve and inserting it into the broken and / or cracked conduit in a contracted state to expand it; And hardening by injecting strength and index reinforcing medicine between the outer surface of the sleeve and the inner wall of the conduit, The plurality of gap maintenance projections are non-excavated conduit repair method, characterized in that coupled to the elastic band provided to surround the outer surface of the sleeve in the circumferential direction at intervals in the longitudinal direction. delete The method of claim 3, Any one of the sleeve and the sealing O-ring is a non-excavation pipe repair method, characterized in that the medicine injection hole and the air discharge hole for the discharge of air when the injection of the medicine is provided. The method of claim 3, The sleeve is non-excavated pipeline repair method characterized in that it has a plurality of corrugated bone formed in the circumferential direction on the outer surface. The method of claim 3, The medicine is a non-excavation pipe repair method, characterized in that the polyester or polyurethane. The method of claim 3, When the step of injecting and curing the strength and index reinforcing agent between the outer surface of the sleeve and the inner wall of the pipeline is completed, the steps are repeated, but the non-excavated pipeline, the continuous installation of the sleeve in the pipeline Repair method.

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