JP2011110856A - Existing conduit repairing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an existing conduit repairing method smoothening insertion operation of a new conduit in a repairing method of the existing conduit by making an intermediate cylindrical body intervene between a new conduit and the existing conduit, and stabilizing the quality of a regenerated conduit after repair and increasing aseismicity. <P>SOLUTION: The existing conduit repairing method includes an intermediate cylindrical body 12 introducing process introducing the intermediate cylindrical body 12 having flexibility in the thickness direction and containing an expansive member into the existing conduit 10 before introducing a new conduit 20 into the existing conduit 10; and a new conduit insertion process inserting the new conduit 20 into the intermediate cylindrical body 12 before the introduced intermediate cylindrical body 12 expands. The repairing method allows easy insertion of the new conduit into the intermediate cylindrical body, and expansion of the intermediate cylindrical body after the introduction of the new conduit fills the space between the existing conduit and the new conduit, to stabilize the new conduit and increase the aseismicity. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an existing pipe repair method, and more particularly to an existing pipe repair method for repairing an existing pipe by inserting a new pipe, which is a new tubular body, into the existing pipe to be repaired.

  In general, for pipes buried in the ground such as sewer pipes, it is inevitable that various deformations will occur over the years since installation, such as cracks, steps due to misalignment, diameter changes, etc. For this reason, there are problems that the flow force of the sewage pipe decreases and the amount of treated sewage increases due to the ingress of groundwater into the pipe. Even in situations where there is no particular deformation, countermeasures for aging and prevention of accidents are necessary, and various repairs are required for existing pipes that have passed a predetermined period after installation. Has been done.

  Currently, the sewage pipe regeneration repair technique is to excavate the ground by work from the ground, excavate the old pipe from the ground and insert a new pipe, repair the inner surface of the pipe from inside the pipe without digging The work method and the method of putting a new pipe in non-open cut are adopted.

  As a repair method for inserting a new pipe by non-open cutting, an uncured tubular lining material is introduced into the existing pipe to be repaired, and after expanding the diameter in the existing pipe, it is cured by light irradiation or heat treatment. In addition to the method of making rehabilitated pipes, as a method of making it easier to ensure homogenization of rehabilitated pipes after completion, so-called sheath pipes are introduced into existing pipes by sequentially connecting new pipes of a predetermined length manufactured in advance at the factory. A construction method called “Sayakan” is known.

  In such a sheath pipe construction method, after the new pipe insertion work is completed, in order to stabilize the structure, a gap filling work is performed between the outer peripheral surface of the new pipe and the inner peripheral surface of the existing pipe, and normally curable filling is performed. Filling with a material such as cement mortar is performed. In order to facilitate the insertion work and the gap filling work, a new pipe having a smaller outer diameter is generally adopted, and the distance between the inner peripheral surface of the existing pipe and the outer peripheral face of the new pipe is relatively large. In this way, in the sheath tube, the new tube inevitably has a smaller inner diameter, and the flow-down capacity is reduced.

  In addition, the applicant of the present invention connects the rehabilitated pipe pieces as disclosed in Patent Document 1 so as to improve the efficiency of the gap filling work and prevent the filling material from leaking into the ground so that the gaps can be filled evenly. Then, in the method of forming a new pipe in the existing pipe, a flexible outer cylinder material is installed between the new pipe and the existing pipe, and fluidity hardening is performed between the new pipe and the outer cylinder material. It proposes a technology that fills the material and finally hardens it to complete the entire rehabilitation pipe. As described above, when a new pipe is inserted into an existing pipe and the existing pipe is repaired, various techniques for filling and curing the filler between the two have been conventionally employed.

Japanese Patent Laid-Open No. 2008-95729

  However, in the above-described conventional technique, it is necessary to perform a work of filling a small space outside the new pipe inserted into the ready-made pipe with a curable filler, but this work is not easy to fill evenly. In addition, installation of a large-scale apparatus and complicated and time-consuming work are required. In addition, if this filling work is not performed accurately, a space will remain between the existing pipe and the new pipe, which will not only adversely affect the quality of the renovated pipe structure after repair. However, there is a risk that groundwater will flow through the remaining space as a passageway, leading to road collapse. Further, since the new pipe and the existing pipe are firmly bonded by the filler, there is a problem that the new pipe and the existing pipe are not flexible and are easily broken during an earthquake.

  In addition, considering the flow capacity of the rehabilitated pipe after construction, it is necessary to suppress the reduction of the inner diameter of the pipe as much as possible. As a result, the reduction in the cross-sectional area becomes large.

  In view of such a situation, the applicant of the present application is not a method of feeding a curable filler while maintaining fluidity between the outer peripheral surface of the new pipe and the inner peripheral surface of the existing pipe. Prior to introducing a pipe into an existing pipe, a technique has been proposed in which an intermediate cylindrical body is introduced into the existing pipe and a new pipe is inserted inside the pipe while being in close contact with the peripheral surface of the intermediate cylindrical body. According to this construction method, it is possible to avoid the occurrence of uneven filling of the filler in the gap between the new pipe and the existing pipe, and it is possible to always ensure stable quality of the renovated pipe.

  In this construction method, when the new tube is inserted into the intermediate cylindrical body, the insertion operation must be performed while bringing the both into close contact so as not to cause a gap. The insertion operation must be performed more smoothly without damaging the body.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to insert a new pipe in a method of repairing an existing pipe by interposing an intermediate tubular body between the new pipe and the existing pipe. The purpose is to provide an existing pipe repair method that can be smoothed, stabilize the quality of the rehabilitated pipe after repair, and improve the earthquake resistance.

In order to solve the above problem, the existing pipe repair method according to claim 1 is:
In the existing pipe repair method in which the existing pipe is repaired by introducing a ready-made new pipe into the existing pipe to be repaired,
Before introducing the new pipe into the existing pipe, the intermediate tubular body having elasticity in the thickness direction and including the expandable member is placed in the existing pipe in a state where the expandable member is not at least completely expanded. An intermediate tubular body introducing step, and a new tube inserting step of inserting the new tube into the intermediate cylindrical body before the introduced intermediate tubular body is at least completely expanded. And

  According to this configuration, since the inflatable member is in a state where the inflatable member is not completely inflated, the intermediate tube is thin and stretchable in the thickness direction. The restraining force and frictional force received from the body are reduced. Accordingly, since the new tube can be smoothly inserted, the insertion operation can be facilitated. In addition, after the introduction of the new pipe, the expansion of the inflatable member further expands the entire intermediate cylindrical body, so that the gap between the new pipe and the existing pipe is filled, effectively avoiding the generation of the remaining space. It is possible to obtain a stable new tube installation state that is elastically constrained by a certain restraining force.

  Furthermore, the smooth insertion of the new pipe prevents the occurrence of damage during the movement of the new pipe in the existing pipe, and the intermediate cylinder as a filling function member for the gap between the new pipe and the existing pipe. It becomes possible to improve the quality of the shape. Since the intermediate cylindrical body has elasticity in the thickness direction and can be compressed, the new pipe can be stably held when the new pipe is inserted, and the existing pipe and intermediate cylindrical body can be used when an earthquake occurs. In addition, due to the configuration of the entire new pipe, the intermediate cylindrical body absorbs the stress due to the earthquake, and the earthquake resistance of the entire pipe can be improved, and a high-performance rehabilitation pipe is formed.

  The existing pipe repair method according to claim 2 is the existing pipe repair method according to claim 1, wherein the intermediate cylindrical body has a thickness that does not exceed the width of the gap between the existing pipe and the new pipe in a normal state. It has a thickness greater than the width when expanded.

  According to this configuration, the thickness of the normal (before expansion) intermediate cylindrical body does not exceed the width of the gap between the existing pipe and the new pipe. Because the restraining force on the new tube is small, the operation of the new tube progressing while closely contacting the intermediate cylindrical body to the peripheral surface of the intermediate cylindrical body becomes smoother, and the rapid processing of this method is achieved. be able to. In addition, since the thickness of the intermediate cylindrical body expands beyond the width of the gap during expansion, the intermediate cylindrical body that has started to expand after insertion of the new tube has reached its thickness after reaching the width of the gap. The expansion force acts in the direction of increasing the density of the intermediate cylindrical body, so that the gap can be reliably filled, so that a more stable installation state of the new pipe can be obtained.

The existing pipe repair method according to claim 3 is the existing pipe repair method according to claim 1 or 2,
The inflatable member is composed of a nonwoven fabric or a woven fabric containing a water-expandable material.

  Existing pipes to be repaired by the method of the present invention are often installed underground, but since there is a lot of underground water underground, this underground water penetrates into the intermediate tubular body through the damaged part of the existing pipe. Then, the water-swellable material swells spontaneously, and the entire intermediate cylindrical body can be expanded. Since the intermediate cylindrical body expands spontaneously in this way, the construction method can be facilitated. In addition, since the inflatable material is composed of a nonwoven fabric or a woven fabric, it is easy to manufacture and easy to handle on site, and since it has a certain water permeability, water permeation is smooth and uniform. Further, after expansion, the water permeability is remarkably lowered, and it is difficult to form a passage for groundwater or the like. As time goes on, the soil particles in the groundwater become clogged and the water permeability is almost lost.

The existing pipe repair method according to claim 4 is the existing pipe repair method according to any one of claims 1 to 3,
The inflatable member is formed of a non-inflatable non-woven fabric or woven fabric on the outer side and a non-woven fabric or woven fabric containing the water-expandable material on the inner side.

  After starting to introduce the intermediate cylindrical body into the existing pipe, it takes a certain amount of time to insert the new pipe into the intermediate cylindrical body. When working in a place where there is a lot of groundwater, during the work of introducing the intermediate tube and new pipe, the groundwater penetrates the intermediate tube through the damaged part of the existing pipe earlier than the intended time. It may expand. If the intermediate cylindrical body expands during the operation of introducing the intermediate cylindrical body and the new pipe, the object of the present invention of smoothly inserting the new pipe cannot be achieved. However, according to this configuration, even if groundwater penetrates into the intermediate tubular body through the damaged portion of the existing pipe, the groundwater penetrates to the non-woven fabric or woven fabric containing the water-expandable material provided inside the intermediate tubular body. Can be prevented for a predetermined time by the non-inflatable nonwoven fabric or woven fabric provided outside the intermediate cylindrical body, so that the unintended early expansion can be avoided, and the intermediate cylindrical body before the expansion The new tube can be inserted in the state.

The existing pipe repair method according to claim 5 is the existing pipe repair method according to any one of claims 1 to 4,
A water-soluble film is provided on the outer peripheral surface of the intermediate cylindrical body.

  According to this configuration, when the intermediate tubular body comes into contact with groundwater in the introduction work of the intermediate tubular body and the new pipe, the water-soluble thin film serves as a barrier (wall), and the water penetration into the intermediate tubular body is prevented. It can be prevented for a predetermined time. Therefore, the non-expanded state can be kept long, and the time for the new tube insertion process can be secured longer.

The existing pipe repair method according to claim 6 is the existing pipe repair method according to claim 1 or 2,
The expandable member is a thermally expandable material, and the expansion is performed by heating the intermediate cylindrical body.

  With this configuration, when repairing an existing pipe installed in the underground where there is a very large amount of groundwater, since it uses a thermally expandable resin instead of a water expandable resin, it will not expand due to groundwater, Until the new tube is inserted, the intermediate tubular body can be maintained in a normal state (before expansion), and the new tube can be smoothly inserted into the intermediate tubular body. It is also effective for repairing existing pipes installed in the underground where there is no groundwater or there is only a small amount even if it exists. After the new pipe insertion process is completed, the intermediate cylindrical body can be arbitrarily expanded by heating, and the gap between the existing pipe and the new pipe can be filled, and the new pipe can be fixed.

  According to the existing pipe repairing method according to the present invention, by using an expansible member for the intermediate tubular body having elasticity in the thickness direction, it is possible to remove the intermediate pipe from the intermediate tubular body in the insertion operation of the new pipe. Improves the propellability of the new pipe with a low restraining force, achieves smoothness and speediness of the new pipe insertion, and expands the gap between the existing pipe and the new pipe after the new pipe is inserted. By satisfying it reliably, it is possible to prevent rattling and protect the new pipe. Thereby, the improvement of the earthquake resistance by the improvement of the quality and stabilization of the renovated pipe formed by insertion of a new pipe, and the softness | flexibility of an intermediate | middle cylindrical body is achieved without complicating work.

(A) And (B) is explanatory drawing which shows the insertion state of the intermediate | middle cylindrical body to the existing pipe, (C) is an expanded sectional view of an intermediate | middle cylindrical body. It is operation | movement explanatory drawing which performs the new pipe introduction process which concerns on this invention. It is explanatory drawing which shows the state after an intermediate | middle cylindrical body expand | swells after a new tube introduction. It is sectional drawing which shows another form of an intermediate | middle cylindrical body. It is sectional drawing which shows another form of an intermediate | middle cylindrical body. It is sectional drawing which shows another form of an intermediate | middle cylindrical body. It is a schematic block diagram which shows the structural example of the moving body which heats an intermediate | middle cylindrical body. It is explanatory drawing which shows the whole sewer main structure as an example to which this invention is applied.

(First embodiment)
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment of the invention will be described in detail with reference to the drawings. FIG. 8 shows an example of a pipe rod to which the existing pipe repairing method of the present invention is applied. As shown in the drawing, a sewer main pipe 10 that is an existing pipe to be repaired is disposed between manholes 100 and 102 installed at a predetermined interval. The case where this sewer main 10 is repaired using the construction method of the present invention will be described as an example.

  1 (A) and 1 (B) show an intermediate tubular body introducing step in the existing pipe repair method according to the present invention, and the state where the intermediate tubular body 12 is introduced into the sewer main pipe 10 to be repaired is shown. It is shown. 1A is a schematic longitudinal sectional view along the extending direction of the sewer main 10, and FIG. 1B is a schematic longitudinal sectional view in a direction orthogonal to the extending direction of the sewer main 10. FIG.

  As shown in the figure, first, an intermediate cylindrical body 12 is drawn into the sewer main pipe 10 from one manhole side (not shown) by, for example, pulling operation by pulling from the other side, and the diameter is increased. There is no state.

  As shown in FIG. 2C, the intermediate cylindrical body 12 is a nonwoven fabric or woven fabric obtained by mixing water-expandable fibers 12a such as sodium polyacrylate and non-expandable fibers 12b such as polyester. The thickness before expansion is set smaller than the width of the gap between the new pipe 20 (new pipe piece 20-1) (shown in FIGS. 2 and 3) and the existing sewer main pipe 10 (for example, 5 mm to 10 mm). And). Since the intermediate cylindrical body is made of a nonwoven fabric or a woven fabric, it has a certain degree of stretchability in the thickness direction.

  In this way, the intermediate cylindrical body 12 is made elastic in the thickness direction, and the thickness is set to be smaller than the gap between the new pipe 20 and the sewer main pipe 10, which will be described later. The new pipe 20 can be introduced smoothly, and the smoothness and quickness of the new pipe 20 insertion work can be achieved. The introduction of the intermediate cylindrical body 12 is not limited to pull-in insertion, and a known reverse insertion method in which the intermediate cylindrical body 12 is fed while being reversed from the inside can also be used.

  FIG. 2 shows a process of inserting the new pipe 20 into the intermediate cylindrical body 12 (new pipe insertion process), and is a sectional view in the pipe axis direction of the sewer main pipe 10 which is an existing pipe. The new pipe 20 is formed in advance by factory production. For example, the new pipe 20 is made of polyethylene, polyvinyl chloride, polybutylene terephthalate, or the like and has an appropriate thickness corresponding to the situation of the sewer main 10 at the installation location. Yes. In addition, the new tube 20 is inserted and installed so that the new tube pieces 20-1 to 20-n formed in a length of about 50 cm to 100 cm, for example, are sequentially connected from the rear, and are continuous over the entire length. Is.

  Further, in the present embodiment, the leading body 14 whose outer diameter gradually decreases toward the leading end is detachably attached to the leading end in the traveling direction of the leading new tube piece 20-1. The head body 14 is formed of, for example, a steel material that is metered and has a hardness that does not deform during the progress, and facilitates the insertion of the new pipe piece 20-1. It is. The maximum outer shape of the top body 14 may be formed slightly larger than the outer shape of the new tube 20.

  The advancement of the new tube piece 20-1 is performed, for example, by pulling the top body 14 in the direction of the arrow 200 with the wire 18 or the like. It is possible to use a normal technique in which a hook portion 16 is provided at the tip of the top body 14 and the hook portion 16 is locked with a wire 18 or the like and pulled. In addition to traction, it is also possible to insert a new pipe by pushing it from the rear (starting side), and using both traction from the front (arrival side) and pushing from the rear (starting side) Can also be done. The new pipe piece 20-1 is shown only at the top, but the new pipe pieces 20-2 to 20-n are sequentially connected from the rear side to connect the new pipe to the entire sewer main 100 to be repaired. Twenty insertions are made.

  In the traveling operation of the new tube 20, the leading body 14 travels while expanding the intermediate tubular body 12. The intermediate tubular body 12 is in a state before expansion (normal state), and its thickness is thinner than the width of the gap between the sewer main pipe 10 and the new pipe 20 which are existing pipes. A space 22 exists between the inner peripheral surface of the sewer main 10. In other words, since there is a certain amount of space for inserting the new tube 20, the new tube 20 can be easily inserted with almost no restraining force (pressing force) from the intermediate cylindrical body.

  FIG. 3 is an explanatory view showing a state after the intermediate cylindrical body is expanded after the new tube is inserted. After the new pipe 20 is inserted, the water-expandable fiber 12a contained in the intermediate cylindrical body 12 expands and the entire intermediate cylindrical body 12 expands to increase the thickness, and the sewer main pipe 10 and the new one that existed in FIG. The space between the pipes 20 is filled, and a stable installation state of the new pipe 20 without rattling is obtained.

  Sewer pipes are generally installed at a depth of about 2 to 3 meters underground, but underground underground at this depth usually contains a lot of ground water, and this ground water passes through damaged parts of the sewer main 10. It penetrates into the intermediate cylindrical body 12. After the new pipe 20 is inserted, the water-expandable fiber 12a contained in the intermediate cylindrical body is expanded by the groundwater, so that the intermediate cylindrical body 12 is expanded and the gap between the new pipe 20 and the sewer main pipe 12 is filled. be able to. Since the intermediate cylindrical body 12 expands to the thickness of the width of the gap between the sewer main pipe 10 and the new pipe 20, it is impossible to expand further, so the expansion force proceeds in the direction of increasing the density. Thereby, the installation state of the new pipe 20 is stabilized, and the intermediate tubular body 12 has flexibility, so that the seismic performance of the new pipe 20 is improved when an earthquake occurs.

  FIG. 4 is a cross-sectional view showing another form of the intermediate cylindrical body. As shown in FIG. 1 (C), the intermediate cylindrical body is not only a nonwoven fabric or a woven fabric in which water-expandable fibers 12a and non-expandable fibers 12b are simply mixed. 12 has a two-layer structure, the upper existing pipe side is a non-expandable fiber layer 32, and the lower new pipe side is a water-expandable fiber layer 30. In order to smoothly introduce the new pipe 20, from the start of the introduction work of the intermediate tubular body 12 to the completion of the new pipe 20 insertion work, the intermediate tubular body 12 is prevented from expanding due to groundwater, and before the expansion. Although it is necessary to maintain a thin state, since the intermediate cylindrical body 12 has a two-layer structure in this way, groundwater that has entered from the outside of the intermediate cylindrical body 12 does not first expand and is not inflatable. Since it penetrates into the fiber layer 32 and then penetrates to the water expansion fiber layer 30, the time for the entire intermediate cylindrical body 12 to start to expand can be delayed. You may change the ratio of the thickness of two layers according to the quantity of the groundwater which exists underground.

  Although not shown, a non-expandable fiber layer 32 may be provided on the peripheral surface of the new tube 20 so that the water-expandable fiber layer 30 is sandwiched between the non-expandable fiber layers 32. With such a configuration, when the intermediate tubular body 12 is inserted into the sewer main pipe 10, even if groundwater enters the inside of the intermediate tubular body 12, a new operation is started from the start of the introduction work of the intermediate tubular body 12. It is possible to ensure a sufficiently long time for inserting the tube 20. A water-expandable foam such as urethane foam that expands with water can be used instead of the water-expandable fiber.

  FIG. 5 is a cross-sectional view showing another form of the intermediate cylindrical body. The intermediate tubular body 12 of this embodiment is obtained by embedding a granular water-expandable foam 34 in a non-expandable fiber layer 36. The granular water-expandable foam 34 has a diameter of 2 to 3 mm. Even with this configuration, as described above, even if groundwater enters the intermediate tubular body 12, the intermediate tubular body 12 can be prevented from expanding while the non-expandable fiber layer 36 is infiltrated. The penetration of groundwater up to the water-expandable foam 34 can be delayed. In addition, you may increase / decrease the magnitude | size and number of the water-expandable foam 34 suitably according to the amount of groundwater similarly to the above.

  FIG. 6 is a cross-sectional view showing another form of the intermediate cylindrical body. In the intermediate cylindrical body 12 of this embodiment, the water-soluble film 40 is provided on both the outer peripheral surface and the inner peripheral surface of the intermediate cylindrical body 12. As shown in FIG. 1 (C), the portion sandwiched between the water-soluble wire membranes 40 is a mixture of water-expandable fibers 12a and non-expandable fibers 12b to form a nonwoven fabric or woven fabric, or in FIGS. 4 and 5 above. Any of those described may be used. The water-soluble film 40 has a thickness of 0.1 to 0.3 mm and is made of a water-soluble polymer such as a water-soluble polyamide. By providing the water-soluble film 40, even when the intermediate cylindrical body 12 and the ground water are in contact with each other during the introduction work of the intermediate cylindrical body 12 and the new pipe 20, the water-soluble film 40 does not allow ground water to reach the intermediate cylindrical body 12. It plays a role of preventing permeation for a predetermined time, and the intermediate cylindrical body 12 and the new pipe 20 can be introduced before the intermediate cylindrical body 12 expands. Moreover, you may change the thickness of the water-soluble film | membrane 40 according to the quantity of the groundwater which exists underground.

(Second Embodiment)
In the second embodiment, a member (thermally expandable member) that expands by heat is used as the expandable member included in the intermediate cylindrical body. As in the first embodiment, the heat-expandable member may be incorporated into a nonwoven fabric or woven fabric made of non-expandable fibers, or the entire intermediate cylindrical member may be made of a heat-expandable member. As the thermally expandable member, thermally foamed urethane or the like can be used.

  Similar to the first embodiment, the intermediate cylindrical body including the thermally expandable member is introduced into the existing pipe, and the new pipe is inserted into the intermediate cylindrical body. Thereafter, heat is applied to the thermally expandable member to expand the intermediate cylindrical body, thereby filling the gap between the existing pipe and the new pipe.

  A heating process is performed by moving a moving body provided with a heating part in a new pipe, heating a new pipe, and transmitting the heat to an intermediate cylindrical body. FIG. 7 is a schematic configuration diagram showing an example of the configuration of the moving body 50. For example, heating means 54 for a heating element such as a heating wire or an infrared light emitting means is loaded inside the casing 52, and this heat is supplied from the casing 52. Is transmitted to the new tube using hot air or light rays as a medium. For example, when a light emitter such as an infrared lamp is used, heat can be accurately transferred to the new tube by configuring the casing 52 with a light-transmitting member. Moreover, when using a heat generating body, it is suitable to attach a fan etc. to a casing and to blow off the heat in a casing to the new tube side. The heating temperature is determined according to the expansion temperature of the thermally expandable member to be used.

  This embodiment is effective for existing pipes installed in the underground where a large amount of groundwater is contained. That is, even if the intermediate tubular body shown in FIGS. 4, 5, and 6 is subjected to the early expansion prevention measures, the intermediate tubular body expands when the intermediate tubular body and the new pipe are introduced. In addition, by using the intermediate tubular body containing the thermally expandable resin shown in the present embodiment, the intermediate tubular body can smoothly insert the new tube in a state before expansion, and after the new tube is inserted Can be inflated arbitrarily. Furthermore, the present embodiment is effective for existing pipes installed in the underground where there is no groundwater or only a small amount even if it exists.

  In addition, this invention is not limited to the structure of said each embodiment, A various deformation | transformation is possible within the range of the summary of invention.

10 Sewer main pipe 12 Intermediate cylindrical body 14 Lead body 16 Hook part 18 Wire 20 New pipe 30 Water-expandable fiber layer 32 Non-expandable fiber layer 34 Water-expandable foam 36 Non-expandable fiber 40 Water-soluble thin film 100, 102 Manhole

Claims (6)

In the existing pipe repair method in which the existing pipe is repaired by introducing a ready-made new pipe into the existing pipe to be repaired,
Before introducing the new pipe into the existing pipe, the intermediate tubular body having elasticity in the thickness direction and including the expandable member is placed in the existing pipe in a state where the expandable member is not at least completely expanded. An intermediate cylindrical body introducing step to be introduced into
A new tube inserting step of inserting the new tube into the intermediate cylindrical body before the introduced intermediate cylindrical body is at least completely expanded;
The existing pipe repair method characterized by including.   The said intermediate cylindrical body has thickness which does not exceed the width | variety of the gap | interval of the said existing pipe and the said new pipe normally, and has the thickness more than the said width | variety at the time of expansion | expansion. Existing pipe repair method.   The existing pipe repairing method according to claim 1 or 2, wherein the inflatable member is made of a nonwoven fabric or a woven fabric containing a water-expandable material.   4. The expandable member according to any one of claims 1 to 3, wherein an outer side is composed of a non-expandable nonwoven fabric or woven fabric, and an inner side is composed of a nonwoven fabric or woven fabric containing the water-swellable material. The existing pipe repair method described.   The existing pipe repair method according to any one of claims 1 to 4, wherein a water-soluble film is provided on an outer peripheral surface of the intermediate cylindrical body. The expandable member is a thermally expandable material,
The existing pipe repair method according to claim 1 or 2, wherein the expansion is performed by heating the intermediate cylindrical body.

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