JPH09292054A - Repairing method for existing buried pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a welding work and a large-scaled working pit by roll-likely winding a pipe constituting material plastically worked into a flat folded shape so as to carry it in a jobfield, inserting it into an existing buried pipe through a working pit, and applying fluid pressure into the pipe constituting material so as to restore it to its original state. SOLUTION: A pipe constituting material 1 is formed out of a metal pipe such as iron pipe into a flat shape by plastically working, and wound up in a roll on a winding core 2. Under this condition it is carried in a jobfield and installed on the ground. Then it is drawn out toward an existing buried pipe (a) through a manhole (b), and directly after drawing out the winding property is corrected into a straight line by straightening rollers 6. Then it is pulled in the existing buried pipe (a) through guide roller device 7 by a traction rope 8. Next, both ends are clamped and closed, water is supplied into the pipe constituting material 1 from the outlet side of the existing buried pipe (a) so as to pressurize it. Hence the pipe constituting material 1 is restored to a circular form. After perfectly restoring, pressure is released, both ends are cut, and hence the laying is completed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for repairing an existing buried pipe, more specifically, by laying a new metal new pipe inside an existing buried pipe such as a sewer pipe, city gas pipe, water pipe, etc. Regarding the repair method to update.

[0002]

2. Description of the Related Art Conventionally, as a method of repairing an existing buried pipe, a standard length steel pipe is inserted into the existing buried pipe while successively adding them by applying welding means in a working pit formed by excavation in the middle of the existing buried pipe. A so-called pipe-in-pipe method of laying a new metal pipe inside the buried pipe has been proposed.

[0003]

However, in the conventional pipe-in-pipe construction method described above, it is necessary to add fixed-length steel pipes by welding in the work pits one by one, which requires a great deal of labor and time for welding. In addition to being not very efficient, it requires a large work space for welding additions and requires excavation and formation of a large-scale work pit, which is not suitable for repairing sewer pipes that use manholes as work pits, for example. It was

[0004] The present invention has been made to solve the above-mentioned conventional problems.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a new metal having an outer diameter corresponding to the inner diameter of an existing buried pipe is plastically deformed into a flat fold shape so as to reduce the effective outer diameter, and is pressurized and expanded from the inside. A pipe pit that can be restored to a pipe is rolled up into the construction site and installed on the ground, and then the pipe pit is pulled out from the winding roll to form a work pit in the ground. After inserting into the embedded pipe through the both ends of the pipe, the pipe constituent material is thereafter restored to a circular cross-sectional shape by fluid pressurization from the inside, whereby the shape of the pipe constituent material is restored in the embedded pipe. This relates to a method of repairing an existing buried pipe, which is characterized by laying a new metal pipe.

Further, according to the present invention, the existing buried pipe is a sewer pipe, and the repair construction method according to claim 1 is applied to the sewer pipe so that a new metal pipe is formed inside and outside, and a peripheral gap is formed between them. The repairing method is characterized in that the backfilling material is injected and filled in the above-mentioned circumferential gap.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the repairing method of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a pipe component 1 according to the method of the present invention.
The state of the insertion process into the existing buried pipe is schematically shown. As the existing buried pipe a, a sewer pipe is shown in the illustrated embodiment.

The pipe component 1 is installed at a construction site in a rolled-up state, and the roll core 2 is a pipe component 1.
In order to easily and smoothly wind up, a large winding diameter is used.

The pipe component 1 is made of a metal pipe such as iron, stainless steel, aluminum, etc., and is plastically deformed into a flat shape so that it can be rolled up. In this flattening process, in order to make an effective cross section that can be inserted into the existing buried pipe a, the flattened shape of the crushed pipe is further folded into two folds.

FIG. 2 schematically shows the procedure of the flat folding process in the order of steps. The original pipe 1a of the pipe component 1 is shown in FIG.
As shown in (a), it has a circular cross section, and its outer diameter is substantially equal to the inner diameter of the existing buried pipe a. The thickness of the raw pipe 1a is relatively thin in consideration of plastic deformation processing, and is, for example, 0.5 to
From within the range of about 4.0 mm 1/100 to 1/5 of the caliber
It is appropriately selected and determined so as to be about 00 in consideration of the material and the like.

In the original pipe 1a, as shown in FIG. 2B, the folded-back portions 1b [FIG.
Curvature control members 3 and 3 for controlling the radius of curvature of [C] are attached and fixed in a temporarily attached state that can be appropriately peeled off over the entire length in the tube axis direction.

In the state shown in FIG. 2B, the original pipe 1a is gradually deformed from a circular cross section to a flat cross section by applying, for example, a flattening roll from the vertical direction, and finally, as shown in FIG. It becomes flat as shown in (c). From this flat state, a deformation processing means is applied as shown in FIG. 2D to perform a deformation processing into a V shape, and as shown in FIG. 2E, a curvature control member is provided at the lower end of the V-shaped valley 5. After the 4 is temporarily attached or freely installed, as shown in FIG. 2F, a flat-folded tube component 1 that can be wound into a roll is obtained by folding it into two folds.

As shown in the enlarged view in FIG. 3, the control members 3 and 4 are sandwiched in the folded-back portions 1b and the intermediate folded-back portion 1c of the pipe component 1, so that the folded-back portions 1b are formed. The folded ends 1b ₁ and 1c ₁ of 1c are not bent at an acute angle. Thus, the control members 3, 4
By properly selecting the material, thickness, cross-sectional shape, etc. of
The radii of curvature of the folded ends 1b ₁ and 1c ₁ can be controlled to a predetermined value.

As the material of the control members 3 and 4, rubber having a cushioning property is suitable, but other materials such as plastic and metal may be used. The cross-sectional shape is shown in FIG.
In addition to the flat plate shape as shown in FIG. 4 and the circular shape as shown in FIG. The use of the control materials 3 and 4 is not always necessary and may be omitted in some cases.

The pipe component 1 is, for example, after being deformed from the raw pipe 1a into a flat folded state or after being deformed in a pipe factory through the steps (a) to (f) shown in FIG. While being rolled up, it is wound into a roll, and under this rolled-up state, as shown in FIG.

As shown in FIG. 1, the pipe constituent member 1 is composed of an existing buried pipe a through a manhole b from a roll installed on the ground.
Be drawn towards.

The pipe component 1 pulled out from the roll passes through the straightening roller device 6 immediately after it is pulled out, the curl is removed during the passage of the roller device 6, and the manhole b is almost straight in the manhole b. It moves downward and is inserted into the existing buried pipe a at the lower end of the manhole b while changing its direction from the vertical direction to the horizontal direction while passing through the guide roller device 7.

As a means for inserting the pipe component 1 into the existing buried pipe a while pulling it out from the roll, a pulling rope 8 is shown in the drawing, and the rope 8 is, for example, a winch (not shown).
Then, the pipe component 1 is pulled and inserted.

After inserting the pipe constituting material 1 over the entire length in the existing buried pipe a between the manholes b, b, the pipe constituting material 1 is separated from the roll side as shown in FIG. For example, a clamp device 9 for restraining the mouth portion in a crimped state is applied and sealed, and further, inlets and outlets 10 and 11 of pressurized fluid such as pressurized water are applied to the vicinity of the clamp devices 9 and 9 by welding means. Install.

Next, as shown in FIG. 6, after the valve 12 on the outlet 11 side is opened, the pump 13 is operated from the inlet 10 side into the pipe component 1 to supply and fill water. The valve 12 is closed, and then the pump 13 is operated to increase the water pressure. When the water pressure in the pipe constituent material 1 reaches a pressure sufficient to plastically deform the pipe constituent material 1, the pipe constituent material 1 moves from the flat folded state (see FIG. 2F) to the original pipe 1a.
Gradually restore to the circular cross section (see Figure 2 (a)).

When the shape restoration progresses to a certain extent, the pipe constituent member 1 tends to open, for example, in a V shape as shown in FIG. 2 (E), and the control member 4 installed in the valley 5 becomes the pipe constituent member 1.
Since it becomes free from the above, at this time, while continuing the pressurization or temporarily stopping it, the control member 4 is replaced with the existing buried pipe a.
Remove from inside.

After removing the control member 4, pressurization is further continued to restore the shape of the pipe component 1 to the state of the original pipe 1a.

After the shape of the pipe constituent material 1 is restored to the state of the original pipe 1a, the pressure is released, and the surplus ends of both ends are cut and removed, so that the metal in the existing embedded pipe a is The new pipe 1A can be installed.

The control members 3 and 3 are left in the laid new metal pipe 1A. The remaining control members 3 and 3 (not shown in FIG. 7) can be removed from the inside of the new pipe 1A by pulling in the folding direction using a wire material (not shown).

Although depending on the flattening condition of the pipe component 1, the new pipe 1A may have wrinkles, though slight plastic strain, at the folded portions 1b and 1c. In order to remove this wrinkle and adjust the shape of the new pipe 1A to have a circular cross section, FIG.
As shown in FIG. 8, by forcibly inserting the pipe expanding device 14 into the new pipe 1A and expanding the pipe, the new pipe 1A can be installed in the existing pipe a in a substantially close contact state as shown in FIG.

When the existing buried pipe receives pressure from the inside like a city gas pipe, a water pipe, etc., the new metal pipe 1A is made of, for example, stainless steel. Since it has a large pressure resistance, there is no particular problem.

However, when pressure from the outside is a problem, such as in a sewer pipe, the new metal pipe 1A is relatively thin and cannot sufficiently resist the external pressure. It is necessary to take

9 to 13 show an example of measures for strengthening against external pressure. According to this strengthening measure, as shown in FIG. 9, another new pipe 1B having a diameter slightly smaller than that of the new pipe 1A is applied to the inside of the new pipe 1A by applying the repairing method described above. After being installed, the latter new pipe 1B is shaped by applying the pipe expanding device 15, as shown in FIG.

The state after shaping is shown in FIG. 11, and a circumferential gap 16 is formed between the inner and outer new pipes 1A, 1B based on the difference in diameter between these new pipes 1A, 1B.

In the space 16 between the new tubes 1A and 1B, as shown in FIG.
As shown in FIG. 2, a back-filling material 17 such as cement milk is injected and filled, and the back-filling material 17 is cured by curing, whereby the pressure resistance against external pressure can be increased.

In order to prevent the deformation of the inner new tube 1B during the filling and filling of the backfill material 17, the inside of the new tube 1B is
Between the plugs 18, 18 installed at both ends, such as water,
The incompressible fluid 19 is filled. If you do this,
As shown in FIG. 13, the outer new pipe 1A is deformed along the unevenness of the inner surface of the buried pipe a by receiving the filling pressure of the backfill material 17,
The inner new tube 1B is beautifully finished in a straight line.

The pressing force required to restore the pipe component 1 to the new pipe 1A varies depending on the material, the diameter, the wall thickness, etc.
For example, in the case of 150 mm (caliber) × 0.8 mm (thickness) made of stainless steel, a pressing force of about 25 to 30 kg / cm ² is sufficient.

FIG. 14 shows an example of a method for manufacturing the pipe component 1, in which the electric resistance welded pipe 22 is manufactured from the coil of the metal strip 20 through the pipe manufacturing line 21 while the electric resistance welded pipe 22 is flattened. It is adapted to be deformed into a flat state during passage, and further to be rolled into a roll at the roll winding section 25 while being folded into a folded state while passing through the folding section 24. In the figure, 26 is a supply part of the curvature control members 3 and 3, 27 is a supply part of the curvature control member 4, and 28 is a winding guide part.

FIG. 15 is a plan view of the flattened portion 23,
A plurality of pairs of left and right processing rolls 23a, 23a, for example, 5
The sets are spaced apart and the spacing between the rolls is progressively narrower on subsequent ones.

The folding processing section 24 is the V-shaped processing section 2 in the first half.
The flat shape is deformed into a V-shape during passage of 4a, and the V-shape can be folded during passage of the folding portion 24b in the latter half. 16 is V
The top view of the type | mold processing part 24a is shown.

In addition, the pipe constituent member 1 may be wound into a roll while being deformed from a flat state to a folded state as in the case of FIG.

[0038]

According to the repairing method of the present invention, the following effects can be obtained.

(A) For laying a new pipe in the existing buried pipe,
Despite the fact that the pipe is a metal pipe, it can be performed without complicated labor such as welding addition, and the new pipe can be installed and the repair can be efficiently performed.

(B) The work pit needs only to have a space through which the flat-folded metal pipe material can pass, and a small-scale work suffices, and the number of steps required for excavating and forming the work pit can be reduced. In the case of a sewer pipe, the manhole can be directly used as a work pit.

(C) In the case of a sewer pipe, a new metal pipe is installed in the inner and outer double pipes and backfilling is performed in the circumferential space between the inner and outer double pipes to enhance the pressure resistance against external pressure. it can.

[Brief description of drawings]

FIG. 1 is an explanatory view schematically showing a situation of a step of inserting a pipe constituent material into an existing buried pipe in a repairing method of the present invention.

FIG. 2 is a schematic explanatory view showing a flattening process state of a pipe constituent material in the order of steps.

FIG. 3 is an explanatory view schematically showing the application state of the curvature control member to the folded-back portion of the pipe constituent material.

FIG. 4 is a diagram showing a modification of FIG. 3;

FIG. 5 is an explanatory view schematically showing an insertion state of a pipe constituent member into an existing buried pipe and a terminal processing state thereof.

FIG. 6 is an explanatory view schematically showing a shape restoration state of a pipe constituent material.

FIG. 7 is an explanatory view schematically showing a shaping condition of a new pipe laid inside the pipe.

FIG. 8 is an explanatory diagram schematically showing a situation after shaping.

FIG. 9 is an explanatory view schematically showing a situation in which another new metal pipe is laid inside the new metal pipe.

FIG. 10 is an explanatory view schematically showing the shaping situation of another new metal pipe.

FIG. 11 is an explanatory view schematically showing the laying situation of two inner and outer new metal pipes.

FIG. 12 is an explanatory view schematically showing a situation where backfilling is performed in the circumferential gap between the inner and outer new metal pipes.

FIG. 13 is an explanatory diagram schematically showing the situation after the backfilling work is completed.

FIG. 14 is an overall side view schematically showing an example of a method for manufacturing a pipe component.

FIG. 15 is a plan view of a flattened portion in FIG.

FIG. 16 is a side view of the folding portion in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe constituent material 2 Core 3 Curvature control member 4 Curvature control member 5 Valley 6 Straightening roller device part 7 Guide roller device part 8 Traction rope 9 Clamping device 10 Inlet 11 Outlet 12 Valve 13 Pump 14 Tube expanding device 15 Tube expanding device 16 Circumferential gap 17 Backfilling Material 18 Plug 19 Fluid 20 Metal Strip 21 Pipe Line 22 ERW Pipe 23 1st Flat Machining Part 24 2nd Flat Machining Part 25 Roll Rewinding Part 26 Curvature Control Member Supply Part 27 Curvature Control Member Supply Part 28 winding guide part

Claims (4)

[Claims] 1. A pipe which is plastically deformed into a flat fold shape so as to reduce the effective outer diameter and can be restored to a new metal pipe having an outer diameter corresponding to the inner diameter of an existing buried pipe by pressure expansion from the inside. After the components are wound into a roll and carried to the construction site and installed on the ground, then while the pipe components are pulled out from the winding roll and inserted into the buried pipe through the work pit formed in the ground Both ends thereof are sealed, and thereafter, the pipe constituent material is restored to a circular cross-sectional shape by fluid pressurization from the inside, so that a new metal pipe is restored in the buried pipe by restoring the shape of the pipe constituent material. A characteristic method of repairing existing buried pipes. 2. The existing buried pipe is a sewer pipe, and a new metal pipe is laid inside the sewer pipe by applying the repairing method according to claim 1 so as to form a gap between the inner and outer double pipes. The repairing method according to claim 1, further comprising injecting and filling a backfill material into the circumferential gap. 3. The repairing method according to claim 2, wherein the backfilling material is injected and filled in a state in which an incompressible fluid is filled in the inner metal new pipe. 4. The pipe forming material is restored to a circular cross-sectional shape, a new metal pipe is laid, and then the new pipe is expanded and shaped by applying a pipe expanding device from the inside. Repair method.