JPH11241786A - Remaking method for existing conduit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a remaking method for an existing conduit which can line the inner surface of the existing conduit having an intermittent part with a pipe liner having shape recoverability. SOLUTION: This remaking method for an existing conduit is to line the inner surface of the existing conduit 2 having an intermittent part with a thermoplastic resin made pipe liner 1. Using a liner deformed so that its cross section outline area is reduced in a condition that shape recoverability performance is added to a cylindrical body at a shape memory temperature as the pipe liner 1, the pipe liner 1 is inserted into the existing conduit 2. In addition, the method consists of a process for installing the pipe liner 1 on the intermittent part of the existing conduit 2, a process for covering a split cylinder shaped body 3 for controlling outline over the outside of the pipe liner 1 on the intermittent part of the existing conduit 2, a process for heating the pipe liner 1 from inside up to the shape memory temperature to recover the conduit to substantially original cylinder body, and a subsequent process for expanding the cylinder body 1' by air pressurization from inside in a preheating condition, adhering it to the inner surfaces of the existing conduit 2 and the split cylinder shaped body 3 for controlling outline, and then air-cooling it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for rehabilitating an existing pipeline in which an inner surface of the existing pipeline having an intermittent portion is lined with a pipe liner made of a thermoplastic resin.

[0002]

2. Description of the Related Art Conventionally, as a method of rehabilitating an aging pipe made of reinforced concrete pipe (fume pipe) or steel pipe, a new resin pipe having a predetermined length and a small diameter is inserted into an existing pipe while sequentially connecting the pipes. And laying a rehabilitation pipeline,
There is known a method of sealing by injecting a backfill material such as mortar or a foamable resin material into a gap with an existing pipeline.

In the rehabilitation method using this backfill material, there is a problem that the effective flow rate is reduced because the inner diameter of the rehabilitation pipe is considerably smaller than the inner diameter of the existing pipe. Since it is necessary to inject a sealing material into the gap between the road and the seal, there is a problem that workability is poor and rehabilitation work is slow.

In view of this point, for example, Japanese Patent Laid-Open No.
No. 31 discloses a pipe liner deformed into a U-shaped cross section having a cylindrical shape at a shape memory temperature made of a thermoplastic resin and drawn into a pipe inner surface such as a sewage pipe by heating and pressure expansion. And lining the inner surface of the pipe.

[0005]

However, in the process of inserting the pipe liner into an existing pipeline laid in a substantially horizontal direction, there is a human hole in the middle of the construction span, or there is an open cut for branch joining. Even when there are intermittent parts such as parts, the construction is performed in a lump with spans by directly indexing to the standing pile.

However, when the pipe liner in this state is heated and pressurized and expanded, the intermittent portion of the existing pipeline is
Since there is no member that regulates the outer shape, there is a problem in that the pipe diameter becomes larger than other portions, or only that portion becomes thinner, which tends to cause uneven thickness.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and a method for rehabilitating an existing pipeline in which an inner surface of the existing pipeline having an intermittent portion can be lined with a pipe liner having shape recoverability. The purpose of this is to provide.

[0008]

The invention according to claim 1 of the present application (invention 1) is a method of lining an existing pipeline having an intermittent portion with a pipe liner made of a thermoplastic resin. A method of rehabilitation, wherein the pipe liner is modified so that the cross-sectional outer area is reduced in a state where the performance of recovering the shape of the cylinder at the shape memory temperature is imparted. Inserting into the existing pipeline and laying also in the intermittent portion of the existing pipeline, covering the outside of the pipe liner of the intermittent portion of the existing pipeline with the outer cylindrical cylinder for regulating the outer shape, Heating the shape from the inside to the shape memory temperature to recover the shape to the substantially original cylinder, and then pressurizing the cylinder with air from the inside in a preheated state to expand the existing pipe and the split cylinder for outer shape regulation Dense on the inner surface of the body After a rehabilitation method of the existing pipe line comprising the step of air cooling.

In the present invention, examples of the material of the pipe liner include a thermoplastic resin such as polyethylene which can be used as a pipe for normal rehabilitation, and high density polyethylene is particularly preferable.

In the present invention, as the pipe liner, a cylindrical pipe extruded from an extruder is cooled to a shape memory temperature, and a shape of recovering a cylindrical shape at the shape memory temperature is given. What deform | transformed so that an inner area may be reduced and what was wound on the drum in this state is used.

[0011]

In the method for rehabilitating an existing pipeline according to the present invention, the pipe liner is deformed so as to have a reduced cross-sectional outer area in a state where the performance of recovering the shape of the cylindrical body at the shape memory temperature is imparted. A step of inserting the pipe liner into the existing pipeline and laying the pipe liner also at the intermittent portion of the existing pipeline, using Covering the body, heating the pipe liner to the shape memory temperature from the inside to recover the shape to the substantially original cylinder, and then pressurizing the cylinder with air from the inside in a residual heat state to expand the existing cylinder. After being brought into close contact with the inner surface of the pipeline and the outer cylinder for outer shape regulation, by the step of air cooling, the outer cylinder for outer shape regulation is put on the outside of the pipe liner in the intermittent portion of the existing pipeline. Regulate its expansion Since steam can be continuously supplied to the inside of a pipe liner inserted into an existing pipeline laid in a substantially horizontal direction, the shape of the pipe liner is uniformly recovered, and the remaining heat inside the cylinder A lining having a smooth inner surface can be obtained by expanding the internal pressure.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a part of a pipe liner used in the present invention, and FIG. 2 is a front view for explaining a manufacturing process of the pipe liner shown in FIG.

As shown in FIG. 1, the pipe liner 1 is
It is made of high-density polyethylene, and has a concave portion 11 along the axial direction on the outer periphery in a state where the capability of recovering a cylindrical shape at the shape memory temperature is provided, so that the area in the cross-sectional outer shape is reduced. It has been transformed. This pipe liner 1
Is laid in an existing pipeline, steam is continuously supplied into the pipe liner 1 to restore the shape of the cylinder, and the cylinder is expanded by applying internal pressure in a preheated state. It is used as a lining material that is tightly fixed to the inner surface of the pipeline.

As a method for manufacturing the pipe liner 1, for example, as shown in FIG. 2, a cylindrical tube is extruded by an extruder 21 (extrusion temperature 190 ° C.), and the cylindrical tube is passed through a cooling water tank 22. Then, it is cooled by a deforming device 23 and pulled by a pulling device 24 so as to have a concave portion along the axial direction on the outer periphery at a shape memory temperature (resin temperature 125 ° C.) at a shape memory temperature (resin temperature 125 ° C.). For example, a method of winding on the 26 is adopted.

Hereinafter, an example of a method for rehabilitating an existing pipeline having an intermittent portion according to the present invention will be described with reference to FIG. First, in the first step, as shown in FIG. 3A, the pipe liner 1 is inserted into the existing pipeline 2 and also laid in the intermittent portion of the existing pipeline.

In the next step, as shown in FIG. 3 (b), the outer cylindrical pipe 3 for regulating the outer shape is fixed to the outside of the pipe liner 1 at the intermittent portion of the existing pipeline. As shown in FIG. 4, the outer shape regulating split tubular body 3 is divided into two such that a tubular body having an inner shape substantially equal to the inner shape of the existing pipeline is cut in the axial direction. A pair of split tubular bodies 31, 31 are hinged between one side edges thereof, and flange portions 32, 32 are formed on the other side edge, and the flange portions 32, 32 can be fixed with fasteners 33. It has been. The outer cylindrical cylinder for regulating the outer shape is not limited to the one having the above-mentioned structure, but can be appropriately used as long as it can be attached to and detached from the outside of the pipe liner at the intermittent portion of the existing pipeline. It may be a fixed type or a band type whose diameter can be freely changed.

In this state, the pipe end of the pipe liner 1 is heated to a shape memory temperature of 125 ° C. As a result, as shown in FIG. 3C, the opposite end of the pipe liner 1 is heated and restored to the cylindrical body 1 ′ whose outer periphery is regulated by the outer tubular member 3.

Finally, as shown in FIG. 3 (d), compressed air is sent into the cylindrical body 1 'from a steam generating / pressurizing unit (not shown) to expand the inside of the cylindrical body 1' and pressurize and expand the existing pipeline 2 and the outer shape. In close contact with the inner surface of the regulating split cylindrical body 3, in this pressurized state,
After cooling and fixing, the lining on the inner surface of the existing pipeline 2 is completed. At this time, the outer-section regulating split tubular body 3 covering the intermittent portion of the existing pipeline 2 may be left as it is, or may be removed.

[0019]

According to the method for rehabilitating an existing pipeline of the present invention as described above, the inner surface of the existing pipeline having an intermittent portion can be lined with a pipe liner having shape recovery properties. .

[Brief description of the drawings]

FIG. 1 is a perspective view showing a part of an example of a pipe liner used in the present invention.

FIG. 2 is a front view showing an example of a method of forming the pipe liner shown in FIG.

FIG. 3 is an explanatory view of a step of an example of a method for rehabilitating an existing pipeline according to the present invention. FIG. 3 (a) shows a step of inserting a pipe liner into the existing pipeline and laying it also in an intermittent portion of the existing pipeline. (B) is a partial cross-sectional view for explaining a step of covering and fixing an outer shape regulating split tubular body to the outside of a pipe liner at an intermittent portion of an existing pipeline, and (c) is a partial cross-sectional view for explaining. A partial cross-sectional view for explaining a process of heating and restoring a pipe liner to a cylindrical body whose outer periphery is regulated by an outer shape regulating split tubular body,
(D) is a partial cross-sectional view for explaining a step of sending compressed air into the cylindrical body, pressurizing and expanding the inside from the inside, and bringing the compressed air into close contact with the existing pipe and the inner surface of the outer shape regulating split tubular body.

FIG. 4 is a front view showing an example of an outer shape regulating split tubular body used in the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe liner 1 'Cylindrical body 3 Split cylindrical body for external shape regulation

Claims (1)

[Claims] 1. A method for rehabilitating an existing pipeline in which an inner surface of the existing pipeline having an intermittent portion is lined with a pipe liner made of a thermoplastic resin, wherein the pipe liner is formed into a cylindrical body at a shape memory temperature. In a state where the recovering performance is provided, the pipe liner is inserted into the existing pipeline using a deformed one having a reduced cross-sectional outer area, and also laid in an intermittent portion of the existing pipeline. Performing a step of covering the pipe liner at the intermittent portion of the existing pipe with an outer shape regulating cylindrical body, and heating the pipe liner to a shape memory temperature from the inside to recover the shape to a substantially original cylindrical body. After that, the cylindrical body is air-pressurized from the inside in a preheated state, expanded and brought into close contact with the existing pipe and the inner surface of the outer shape regulating split cylindrical body, and then air-cooled. Existing How to rehabilitate the pipeline.