JP2021115750A - Existing pipe renovation method - Google Patents

Abstract

To provide a method of preventing occurrence of buckling in the neighborhood of a pipe edge of the renovation pipe, in an expander pipe making method.SOLUTION: A spiral pipe shaped renovation pipe 3 is made into smaller diameter than the existing pipe 1 and arranged in the existing pipe 1. Edge portions 13 and 14 are made to be in a relatively slidably weakly restrained state toward the winding direction in order of from a pipe edge 3f of the second end side of the renovation pipe 3 toward the first side, and by sending the belt like member 10 to the renovation pipe 3 by an expansion pipe making machine 20 installed in a manhole 4, the pipe portion having a weakly restrained state in the renovation pipe 3 is enlarged. After the enlarging process is performed close to a pipe mouth 1e, the renovation pipe 3 is separated from the expansion pipe making machine 20. After the renovation pipe 3 is made a weakly restrained state up to the pipe edge 3e, and after the separation step, a first side pipe portion 3g of the renovation pipe 3 is naturally expanded.SELECTED DRAWING: Figure 5

Description

The present invention relates to a method for rehabilitating an old existing pipe, and more particularly to an existing pipe rehabilitation method for constructing a spiral tubular rehabilitation pipe along the inner circumference of the existing pipe.

A method of constructing a rehabilitation pipe in an existing pipe such as an aged sewer pipe to rehabilitate the existing pipe is known. As a rehabilitation tube, a spiral tubular rehabilitation tube in which a strip-shaped member is spirally wound and adjacent edge portions are joined by concave-convex fitting is known.
In Patent Document 1, a spiral tubular rehabilitation pipe having a diameter smaller than that of the existing pipe is manufactured and installed in the existing pipe, and then an expansion machine is used to wind the adjacent edge portions of the strip-shaped members constituting the rehabilitation pipe. An expander pipe manufacturing method for expanding (expanding) the diameter of a rehabilitated pipe by sliding it relative to each other in a direction is described. The expanded rehabilitation pipe sticks to the entire circumference of the existing pipe.

In the expander pipe making method of Patent Document 2, an extrusion type pipe making machine is installed in a manhole where the pipe openings on the first side of the existing pipe are connected, and the pipe making machine is used to make the rehabilitated pipe and expand the diameter. I do. At the time of pipe making, a restraining strip is sandwiched between adjacent edge portions of the spirally wound strip-shaped member. After pipe making, the pipe making machine (expansion) while pulling out the restraint strip sequentially from the end of the rehabilitated pipe on the side opposite to the pipe making machine (second side) toward the pipe making machine side (first side). By driving the pipe making machine), the band portion of the band-shaped member connected to the rehabilitation pipe is sent to the rehabilitation pipe. As a result, the diameter of the portion of the rehabilitation pipe from which the restraining strip has been pulled out is expanded (expanded). The portion of the rehabilitation tube that is undergoing diameter expansion deformation becomes a cone shape (conical shape) that expands in diameter toward the second side. A straight pipe portion with an enlarged diameter is connected to the second side.

International Publication No. WO87 / 05677 Japanese Unexamined Patent Publication No. 04-232023

When constructing this type of expander pipe, it is important to control the length of the cone-shaped pipe during diameter expansion and deformation. If the cone-shaped pipe portion is too long, poor sticking to the inner surface of the existing pipe will occur.
On the other hand, if the cone-shaped tube portion is too short, the taper angle becomes excessive, and the buckling (edge portions) is formed between the undiametered tube portion (the unpulled portion of the restraint strip) and the cone-shaped tube portion. Breakage of uneven fitting) occurs. In particular, at the stage where the diameter of the rehabilitated pipe is expanded to the vicinity of the pipe end on the expansion pipe making machine side (first side), the length of the cone-shaped pipe portion cannot be secured and buckling is likely to occur. Once buckling occurs, complicated repair work is required, and in some cases, pipe production must be redone, resulting in a large work loss.
In view of such circumstances, it is an object of the present invention to prevent buckling from occurring near the pipe end of the rehabilitated pipe, particularly on the expansion pipe making machine side (first side), in the expander pipe making method.

In order to solve the above problems, the present invention is a method of rehabilitating an existing pipe with a spiral tubular rehabilitation pipe.
The rehabilitation is performed by winding the strip-shaped member in a spiral along the inner surface of the existing pipe and joining the adjacent edge portions of the strip-shaped member on both sides in the band width direction so as to be in a strongly restrained state. A pipe making process for producing a pipe having a smaller diameter than the existing pipe,
A restraint weakening step in which the edge portions of the rehabilitated pipe are sequentially slidable in the winding direction from the end of the second side to the first side.
By the expansion pipe making machine that engages with the pipe end on the first side of the rehabilitation pipe, the band portion of the strip-shaped member following the rehabilitation pipe is sent to the rehabilitation pipe to bring the rehabilitation pipe into the weakly restrained state. The diameter expansion process to expand the diameter of the pipe that has become
After performing the diameter expansion step until the first end of the diameter-expanded pipe portion is arranged at a predetermined position near the expansion pipe making machine, the rehabilitation pipe is removed from the expansion pipe making machine. The separation process to separate and
After the rehabilitation pipe is brought into the weak restraint state to the first side pipe end by the restraint weakening step and after the separation step, from the predetermined position of the rehabilitation pipe to the first side pipe end. A natural diameter expansion process that naturally expands the diameter of the first side pipe,
It is characterized by being equipped with.

The strong restraint state means a state in which the binding force (friction resistance) between the edge portions is stronger than the weak restraint state.
The natural diameter expansion means that the first side pipe portion is naturally expanded in diameter by its own elastic force to return to the flat plate state without applying a diameter expansion force to the first side pipe portion from the outside.
Since the first side pipe portion is released from the expansion pipe making machine and is in a weakly restrained state, the diameter is naturally expanded by the elastic force that tries to return to the flat plate state by itself. At this time, since an unreasonable external force does not act on the first side pipe portion, buckling hardly occurs. Therefore, the first side pipe portion can be attached to the inner peripheral surface near the pipe mouth of the existing pipe while preventing buckling. There is no need to repair the buckling or redo the pipe making, and work loss can be avoided.

It is preferable that the manual diameter-expanding step of forcibly increasing the diameter of the first-side pipe portion by manually twisting the pipe end on the first side is interposed in the natural diameter-expanding step.
By auxiliary manual diameter expansion, the first side pipe portion can be reliably attached to the first side pipe opening of the existing pipe. Preferably, at the time of manual diameter expansion, the taper angle, length, joint state between the edge portions, etc. of the cone-shaped pipe portion during the diameter expansion deformation in the first side pipe portion are visually observed so that buckling does not occur. Adjust the twisting force. When buckling is likely to occur, the twisting operation can be stopped immediately because it is manual, and the necessary treatment can be performed.

In the pipe making step, the pipe end on the first side of the rehabilitation pipe is projected from the pipe mouth on the first side of the existing pipe.
In the cutting step, the rehabilitated pipe is cut outside the pipe mouth, and the cutting distance between the cutting position and the pipe mouth is increased by expanding the diameter of the first side pipe portion. It is preferable that the end of the pipe is located in the mouth of the pipe or is set so as to protrude from the mouth of the pipe.
Along with the natural diameter expansion of the first side pipe portion, the pipe end (cut end) on the first side of the rehabilitated pipe protruding from the pipe mouth is gradually shifted toward the pipe mouth. On the other hand, by setting the cutting distance, the end of the rehabilitated pipe on the first side does not finally retract into the existing pipe from the pipe mouth after the natural diameter expansion or the like. As a result, the rehabilitation pipe can be attached to the pipe mouth of the existing pipe. It is possible to prevent the inner peripheral surface of the pipe opening from being exposed due to insufficient dimensions of the rehabilitated pipe.

In the pipe making process, a strip is sandwiched between the edge portions of the strip-shaped member.
In the restraint weakening step, it is preferable to sequentially pull out the strip by pulling a take-up portion drawn from the rehabilitation pipe in the strip and passed through the inner space of the rehabilitation pipe.
By pulling out the strip, the binding force between the edge portions can be weakened.

A plurality of fitting protrusions are formed on one edge portion of the strip-shaped member, and a plurality of fitting grooves into which the fitting protrusions are fitted are formed on the other edge portion.
It is preferable that a part of the fitting convex portion is cut by pulling out the strip in the restraint weakening step.
By cutting the part of the fitting convex portion, the binding force between the edge portions can be surely weakened.

A pipe making machine is installed in a manhole connected to the pipe opening on the first side of the existing pipe, and the pipe making process is performed by the pipe making machine.
After that, it is preferable to use the pipe making machine as the extended pipe making machine.
As a result, the pipe making process and the diameter expanding process can be performed using the same device.

According to the present invention, it is possible to prevent buckling from occurring near the pipe end on the expansion pipe making machine side of the rehabilitated pipe during expander pipe making.

FIG. 1 is a cross-sectional view showing an existing pipe under rehabilitation work in a state at the end of the pipe making process of the rehabilitated pipe. FIG. 2A shows an example of a strip-shaped member constituting the rehabilitation tube, and is a cross-sectional view taken along the line IIa-IIa of FIG. FIG. 2B is an enlarged cross-sectional view of the circular portion IIb of FIG. 1 showing a fitting structure between adjacent edge portions of the spiral strip-shaped member in the rehabilitation pipe in a strongly restrained state. FIG. 2C is an enlarged cross-sectional view of the circular portion IIc of FIG. 3 showing the fitting structure in a weakly restrained state. FIG. 3 is a cross-sectional view showing a restraint weakening step and a diameter expanding step in the rehabilitation work of the existing pipe. FIG. 4A is a cross-sectional view showing one aspect of the cutting step in the rehabilitation work of the existing pipe. FIG. 4B is a cross-sectional view showing another aspect of the cutting step. FIG. 5 is a cross-sectional view showing a natural diameter expansion process in the rehabilitation work of the existing pipe. FIG. 6 is a cross-sectional view showing an auxiliary manual diameter expansion process for natural diameter expansion. FIG. 7 is a cross-sectional view showing the end of the natural diameter expansion step and the like.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the existing pipe 1 to be rehabilitated is, for example, a sewer pipe buried in the ground, but the present invention is not limited to this, and the present invention is not limited to this, and is a water pipe, an agricultural water pipe, a gas pipe, and a hydraulic power generation. In addition to water pipes and other buried pipes, tunnels and the like can be mentioned. The existing pipe 1 is rehabilitated by lining the rehabilitation pipe 3 on the inner circumference of the aged existing pipe 1.

The rehabilitation pipe 3 is a spiral pipe made of a strip-shaped member 10. The material of the strip-shaped member 10 is made of a synthetic resin such as polyvinyl chloride (PVC).
As shown in FIG. 2A, the strip-shaped member 10 has a constant cross-sectional shape and extends in the strip length direction orthogonal to the paper surface in the figure. Specifically, the strip-shaped member 10 includes a flat strip-shaped strip portion 11, a plurality of ribs 12 in the middle of the strip portion 11 in the strip width direction, and uneven fitting portions 13 on both sides in the strip width direction. It has 14 integrally. A first fitting portion 13 is provided on the edge portion 10a on one side of the strip-shaped member 10 in the band width direction. The first fitting portion 13 includes two (plurality) fitting convex portions 13a and 13b. A second fitting portion 14 is provided on the edge portion 10b on the other side of the strip-shaped member 10 in the band width direction. The second fitting portion 14 includes two (plural) fitting grooves 14a and 14b.
The cross-sectional shape of the strip-shaped member 10 can be appropriately modified.

The rehabilitation tube 3 is produced by the following expander tube manufacturing method.
<Pipe making process>
As shown in FIG. 1, a push-type pipe making machine 20 is prepared. The pipe making machine 20 is installed at the bottom of a manhole 4 connected to the pipe opening 1e on the starting side (first side) of the existing pipe 1. The strip-shaped member 10 is sequentially fed from the take-up drum (not shown) on the ground and supplied to the pipe making machine 20.
In the pipe making machine 20, the strip-shaped member 10 is spirally wound, and the fitting portions 13 and 14 of the adjacent edge portions 10a and 10b, which are offset from each other by one circumference, are joined by uneven fitting. As a result, the spiral rehabilitation tube 3 is produced. As shown in FIG. 2B, the fitting convex portion 13a is fitted into the fitting groove 14a, and the fitting convex portion 13b is fitted into the fitting groove 14b. Due to the uneven fitting of the two strips (plurality) of the fitting portions 13 and 14, the edge portions 10a and 10b are in a strongly restrained state in which they cannot slide relative to each other in the winding direction.
Preferably, the adhesive 51 is provided in the fitting groove 14a, and the sealing agent 52 is provided in the fitting groove 14b. More preferably, the sealant 52 has lubricity.

At the same time, the wire 41 (strand) is fed out from the feeding reel 42 and introduced into the pipe making machine 20. In the pipe making machine 20, the wire 41 is inserted between the fitting protrusions 13a and 13b and sandwiched between the fitting portions 13 and 14.
The take-up portion 41b on the tip side of the wire 41 is pulled out in advance from the tip 3f of the rehabilitation pipe 3 in the unwinding stage before the main push pipe making, folded back, passed through the internal space of the rehabilitation pipe 3, and the starting side person. It is wound around the take-up reel 43 in the hole 4. A folded portion 41c of the wire 41 is provided at the tip 3f.

The rehabilitation pipe 3 thus produced is sequentially extruded from the pipe making machine 20 and inserted into the existing pipe 1. The tip 3f (the end of the second side) of the rehabilitation pipe 3 may be towed.
As shown in FIG. 1, the outer diameter (pipe making diameter) of the rehabilitated pipe 3 at the time of pipe making is made smaller than the inner diameter of the existing pipe 1. As a result, the friction between the rehabilitation pipe 3 and the existing pipe 1 being pushed into the existing pipe 1 is reduced.

The pipe manufacturing is performed until the tip 3f of the rehabilitation pipe 3 reaches the pipe opening 1f on the reaching side (second side) of the existing pipe 1. As a result, the rehabilitation pipe 3 is arranged in the entire area of the existing pipe 1. Preferably, the tip 3f of the rehabilitation pipe 3 is prevented from rotating with respect to the pipe opening 1f by a jig (not shown) or the like.
The pipe end on the starting side (first side) of the rehabilitation pipe 3 is engaged with the pipe making machine 20 in the manhole 4.

By the pipe making step, the wire 41 is embedded in the rehabilitation pipe 3 in a state of being spirally wound along the strip-shaped member 10 over the entire area of the rehabilitation pipe 3. The take-up portion 41b of the wire 41 is passed through the entire internal space of the rehabilitation pipe 3 so as to connect the tip 3f and the take-up reel 43.

<Restriction weakening process>
After the pipe is manufactured, as shown in FIG. 3, the take-up portion 41b is wound by the take-up reel 43 and pulled in the direction of the pipe axis. As a result, the embedded portion 41a of the wire 41 is sequentially pulled out from the rehabilitation pipe 3, and the folded portion 41c of the wire 41 spirals from the second side to the first side (from the right side to the left side in FIG. 3). It is transferred along the winding direction of. At this time, as shown in FIG. 2C, the root portion of a part of the fitting convex portion 13a of the fitting portion 13 is cut by the folded-back portion 41c of the wire 41. As a result, the binding force between the edge portions 10a and 10b is sequentially weakened from the tip 3f of the rehabilitation tube 3 toward the first side, and the edge portions 10a and 10b are weakly restrained so as to be relatively slidable in the winding direction. Become in a state.

<Diameter (expansion) process>
In parallel with the restraint weakening step by winding the wire 41, the pipe making machine 20 sends the band portion 19 following the rehabilitation pipe 3 in the band-shaped member 10 to the rehabilitation pipe 3 and incorporates it into the rehabilitation pipe 3. As a result, the straight pipe portion 3a having a constant diameter in the rehabilitated pipe 3 in the strongly restrained state is twisted. That is, the entire straight tube portion 3a is pushed to the second side (right side in FIG. 3) while being integrally rotated. In the weakly restrained pipe portion of the rehabilitated pipe 3, the edge portions 10a and 10b slide so as to be displaced from each other along the winding direction, and the diameter is expanded (expanded). In the tube portion in the weakly restrained state, the tube portion 3c undergoing diameter expansion deformation becomes a cone shape (conical cone shape) whose diameter expands toward the second side. A straight pipe portion 3b having an enlarged diameter is connected to the second side of the cone-shaped pipe portion 3c. The straight pipe portion 3b has a larger diameter than the straight pipe portion 3a in the strongly restrained state, and is attached to the entire inner peripheral surface of the existing pipe 1.
The pipe making machine 20 used in the pipe making process becomes an extended pipe making machine.

The restraint weakening step and the diameter expanding step are not limited to be performed in parallel, and the restraint weakening step and the diameter expanding step may be alternately performed little by little. Care should be taken so that the restraint weakening step is preceded too much and the diameter of the first side portion is expanded first so that sticking defects do not occur.
As the restraint weakening step and the diameter expanding step progress, the cone-shaped tube portion 3c shifts to the first side (left side in FIG. 3), the large-diameter straight tube portion 3b extends to the first side, and the small-diameter straight portion 3b. The shape tube portion 3a shrinks.

As shown in FIG. 4, the first end of the enlarged pipe portions 3c and 3b, that is, the small diameter side end portion 3d of the cone-shaped pipe portion 3c is a predetermined portion near the pipe opening 1e and the pipe making machine 20. The restraint weakening step and the diameter expanding step are performed in parallel until the position 1d is reached.
The predetermined position 1d is set in consideration of the distance to the pipe making machine 20 and the like so that the cone-shaped pipe portion 3c can be maintained at a taper angle and length that do not cause buckling.
_{The predetermined distance L 1} between the pipe opening 1e and the predetermined position 1d is preferably about _{L 1} = 1 × P _3a to 30 × P _{3a with} respect to _{the winding pitch P 3a} of the straight pipe portion 3a.

As shown in FIG. 4, when the small diameter side end portion 3d of the cone-shaped tube portion 3c reaches the predetermined position 1d, the diameter expansion step is terminated.
<Separation process>
Then, the rehabilitation pipe 3 is separated from the expansion pipe making machine 20 in the manhole 4. Specifically, the rehabilitation pipe 3 is cut at the position 3p between the expansion pipe making machine 20 and the pipe opening 1e. Cutting the cutting distance L ₂ between the position 3p and Kanguchi 1e, the first side of the pipe end 3e (cut end) of the rehabilitating pipe 3 after later natural diameter step and manual diameter step is slightly above the tube opening 1e Set to protrude. Preferably consider in setting the diameter difference between the straight tube portion 3a and Kanguchi 1e, the distance _{L 1,} the pitch _{P 3a} like.

<Step of weakening restraint of 1st side pipe 3g>
Before and after the cutting step, the entire area of the small-diameter straight first side pipe portion 3g from the predetermined position 1d to the pipe end 3e in the rehabilitation pipe 3 is put into a weakly restrained state.
As shown in FIG. 4A, when the restraint weakening step of the first side pipe portion 3g is performed before the cutting step, the wire 41 is taken up to at least the position 3p, and then the rehabilitation pipe 3 is cut at the position 3p. do.

As shown in FIG. 4B, when the restraint weakening step of the first side pipe portion 3g is performed after the cutting step, the take-up reel without cutting the take-up portion 41b of the wire 41 during the cutting step. Connect with 43. The embedded portion 41a of the wire 41 is cut together with the rehabilitation pipe 3 and separated from the feeding reel 42. The cut end 41e of the buried portion 41a after cutting is fastened to the pipe end 3e of the rehabilitation pipe 3 with a clamp 44. Then, after the cutting step, the wire 41 is wound by the take-up reel 43.

<Natural diameter expansion process>
As shown in FIG. 5, the first side tube portion 3g is left for a while after the cutting step and after the restraint weakening step of the first side tube portion 3g. Since the first side pipe portion 3g is released from the pipe making machine 20 and is in a weakly restrained state, the diameter is naturally expanded by the elastic force that tries to return to the flat plate state by itself. At this time, since an unreasonable external force does not act on the first side pipe portion 3g, buckling hardly occurs. Therefore, as shown in FIG. 7, the first side pipe portion 3g can be attached to the inner peripheral surface of the existing pipe 1 near the pipe opening 1e while preventing buckling.

<Manual diameter expansion process>
As shown in FIG. 6, when the sticking is insufficient or it takes a long time, the manual diameter expansion step may be additionally intervened in the natural diameter expansion process. That is, the diameter of the first side pipe portion 3g is forcibly expanded by manually twisting the pipe end 3e.
In the manual diameter expansion step, preferably, a hole 3h is formed near the pipe end 3e, a rod material 5 such as a straight pipe is penetrated, and the rod material 5 is turned by hand to obtain a first side pipe portion of 3 g. Apply a twisting force to. The hole 3h is formed so as to avoid the fitting portions 13 and 14 and thus the embedded portion 41a of the wire 41.

By manually expanding the diameter of the first side tube portion 3g, the taper angle of the cone-shaped tube portion 3c during the diameter expansion deformation and the fitting state of the fitting portions 13 and 14 can be visually observed. Thereby, the torsional force can be adjusted so that the buckling does not occur in the first side pipe portion 3g, particularly in the cone-shaped pipe portion 3c. When buckling is likely to occur, the twisting operation can be stopped immediately because it is manual, and the necessary treatment can be performed. As a result, the diameter of the first side pipe portion 3g can be increased while preventing buckling from occurring, and the first side pipe portion 3g can be attached to the inner peripheral surface of the existing pipe 1. Therefore, it is not necessary to repair the buckling or redo the pipe making, and work loss can be avoided.

With the natural and manual diameter expansion of the first side pipe portion 3g, the pipe end 3e protruding into the manhole 4 is gradually retracted toward the pipe opening 1e. On the other hand, by setting the cutting distance L ₂ described above, the tube end 3e is never retracts existing pipe 1 than even the tube opening 1e as it no matter how retracted. Therefore, as shown in FIG. 7, the rehabilitation pipe 3 can be reliably attached to the pipe opening 1e of the existing pipe 1. It is possible to prevent the inner peripheral surface of the pipe opening 1e from being exposed due to insufficient dimensions of the rehabilitation pipe 3.
As positioned naturally expanded and manual diameter after pipe end 3e exactly tube opening within 1e, may set the cut distance L _2.
A backfilling material such as mortar may be filled between the inner peripheral surface of the existing pipe 1 and the rehabilitation pipe 3.
In this way, the existing pipe 1 is rehabilitated.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, after the natural diameter expansion immediately after the first side pipe portion 3g is released by the cutting step, the diameter is forcibly expanded until the first side pipe portion 3g sticks to the inner peripheral surface of the existing pipe 1 by manual diameter expansion. You may let me.
In the pipe making process, restraining strips are sandwiched between adjacent edge portions of the spiral strip-shaped members in the rehabilitation pipe to put these edge portions in a strongly restrained state, and in the restraint weakening step, the restraining strip is placed. By pulling out the body from the gap between the edge portions, the strong restraint state may be released and the weak restraint state may be obtained.
In the cutting step, the expansion pipe making machine may be disassembled to separate from the rehabilitation pipe 3.
The extended pipe making machine may be prepared separately from the pipe making machine that performs the pipe making process. The pipe making process may be performed by a traction type pipe making machine, and the diameter expanding process may be performed by an extended pipe making machine including a push-type pipe making machine.
The cross-sectional shape of the rehabilitation tube after the diameter expansion (expansion) does not have to be a circle, but may be an ellipse or a square.

The present invention can be applied to, for example, rehabilitation work of an aged sewer pipe.

L ₁ Predetermined distance L ₂ Cutting distance P _3a Winding pitch 1 Existing pipe 1d Predetermined position 1e Tube mouth 1f on the starting side (first side) Pipe mouth on the reaching side (second side) 3 Rehabilitation pipe 3a Small diameter straight pipe 3b Large-diameter straight pipe 3c Cone-shaped pipe 3d Small-diameter side end (first end of the enlarged pipe)
3e pipe end (first side pipe end)
3f tip (2nd side pipe end)
3g 1st side pipe part 3p Cutting position 4 Manhole 10 Band-shaped members 10a, 10b Edge part 13 1st fitting part (fitting part)
13a Fitting convex part (partial fitting convex part 13b fitting convex part 14 second fitting part (fitting part)
14a, 14b Fitting groove 19 Band part 20 Pipe making machine (Expanded pipe making machine)
41 wire (strand body)
41a Buried part 41b Take-up part 41c Folded part 41e Cut end 44 Clamp (fastening means)

Claims (6)

It is a method of rehabilitating an existing pipe with a spiral tubular rehabilitation pipe.
The rehabilitation is performed by winding the strip-shaped member in a spiral along the inner surface of the existing pipe and joining the adjacent edge portions of the strip-shaped member on both sides in the band width direction so as to be in a strongly restrained state. A pipe making process for producing a pipe having a smaller diameter than the existing pipe,
A restraint weakening step in which the edge portions of the rehabilitated pipe are sequentially slidable in the winding direction from the end of the second side to the first side.
By the expansion pipe making machine that engages with the pipe end on the first side of the rehabilitation pipe, the band portion of the strip-shaped member following the rehabilitation pipe is sent to the rehabilitation pipe to bring the rehabilitation pipe into the weakly restrained state. The diameter expansion process to expand the diameter of the pipe that has become
After performing the diameter expansion step until the first end of the diameter-expanded pipe portion is arranged at a predetermined position near the expansion pipe making machine, the rehabilitation pipe is removed from the expansion pipe making machine. The separation process to separate and
After the rehabilitation pipe is brought into the weak restraint state to the first side pipe end by the restraint weakening step and after the separation step, from the predetermined position of the rehabilitation pipe to the first side pipe end. A natural diameter expansion process that naturally expands the diameter of the first side pipe,
An existing pipe rehabilitation method characterized by being equipped with. The first aspect of the present invention is characterized in that a manual diameter-expanding step of forcibly increasing the diameter of the first-side pipe portion by manually twisting the pipe end on the first side is intervened in the natural diameter-expanding step. The existing pipe rehabilitation method described. In the pipe making step, the pipe end on the first side of the rehabilitation pipe is projected from the pipe mouth on the first side of the existing pipe.
In the cutting step, the rehabilitated pipe is cut outside the pipe mouth, and the cutting distance between the cutting position and the pipe mouth is increased by expanding the diameter of the first side pipe portion. The existing pipe rehabilitation method according to claim 1 or 2, wherein the pipe end of the pipe is set to be located in the pipe mouth or protrude from the pipe mouth. In the pipe making process, a strip is sandwiched between the edge portions of the strip-shaped member.
Claims 1 to 3 characterized in that, in the restraint weakening step, the strips are sequentially pulled out by pulling a take-up portion drawn from the rehabilitation pipe in the strip and passed through the inner space of the rehabilitation pipe. The method for rehabilitating an existing pipe according to any one of the above. A plurality of fitting protrusions are formed on one edge portion of the strip-shaped member, and a plurality of fitting grooves into which the fitting protrusions are fitted are formed on the other edge portion.
The existing pipe rehabilitation method according to claim 4, wherein a part of the fitting convex portion is cut by pulling out the strip in the restraint weakening step. A pipe making machine is installed in a manhole connected to the pipe opening on the first side of the existing pipe, and the pipe making process is performed by the pipe making machine.
The existing pipe rehabilitation method according to any one of claims 1 to 5, wherein the pipe making machine is then used as the extended pipe making machine.

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