JP3498809B2 - Method of forming cable laying pipe - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for laying a cable such as a power line or a communication line, which mainly uses an existing pipeline buried in the ground, and a method for forming the cable laying pipe. Is.

[0002]

2. Description of the Related Art Conventionally, a cable such as a power line or a communication line has been laid by inserting it into a pipeline buried in the ground. In particular, in the communication line, the diameter of the conduit was considerably large in order to secure as many lines as possible.

However, in recent years, the performance of cables has been improved, and moreover, optical fiber cables have been widely used, and it has become possible to support a large number of lines with a small diameter, and a plurality of cables can be installed in an existing pipeline. It has become conceivable to lay it and make effective use of large-diameter pipelines.

An example of such a cable laying pipe is Japanese Patent Laid-Open No. Sho 63
The one described in No. 181608 is known. This is one in which a plurality of tubes are inserted into an existing pipeline, and a cable is inserted into each of the tubes to be laid.

[0005]

However, in this method, the tube inserted into the conduit has a flexible small diameter, and is not restricted to the conduit so that Since it was in a state where it could move freely, the position of the tube was not stable and it was difficult to insert the cable.

[0006] Many of the pipelines have been buried in the ground for a long period of time and may be damaged. However, in the above method, the pipelines themselves are not repaired or reinforced, so they are damaged. There were cases where groundwater, etc. entered from the department.

The present invention has been made in view of the above circumstances, in which the existing pipeline is lined and repaired, and
It is intended to form a plurality of through holes for inserting a cable, which are fixed to the conduit, in the inside thereof.

[0008]

[0009]

[0010]

According to the present invention, therefore, one end of the airtight tube for inversion is fixed in an annular shape at one end of the main tubular body, and pressure is applied to the rear portion of the annular fixing portion by the reaction-curable resin liquid. Then, while the inversion airtight tube is inverted so that the inner side is the outer side in the folded portion formed in the annular fixing portion, the folded portion is advanced into the main pipe body, and the inverted airtightness is inverted to the inner surface of the main pipe body. Forming an airtight layer by a flexible tube, filling the reaction-curable resin liquid in the airtight layer, and connected to the other end of the reversing airtight tube as the reversal of the reversing airtight tube progresses. A plurality of individual tubes are pulled into the reversing airtight tube, and the reversing airtight tube which has been turned upside down over substantially the entire length of the main tube is inserted therethrough. The reaction-curable resin liquid is filled in the space between the airtight tube for reversing and the individual tube, and the reaction-curable resin liquid is filled in a cylindrical shape. It is characterized in that the resin liquid is cured.

In this method, a string-shaped long object is inserted into the airtight tube for inversion over its entire length, and the string-shaped elongated object protruding from the folded portion of the airtight tube for inversion is inserted. By pulling through the main pipe, the folded-back portion can be advanced.

Further, in this method, by applying a fluid pressure in the individual tube, the reaction-curable resin liquid can be cured in a state where the individual tube is expanded in a cylindrical shape.

In this method, it is also possible to use, as the individual tube, one having an external pressure-retaining property that is not easily crushed by the external pressure of the reaction-curing resin liquid.

In the method of the present invention, the reversing airtight tube is inserted over substantially the entire length of the main tube, and the individual tube is inserted into the reversing airtight tube. Both ends are heated from the outside of the reversible airtight tube to cure the reaction-curable resin liquid at the relevant point, and even after that, even when the reaction-curable resin liquid inside is uncured, the reversible airtightness is kept at the relevant point. The flexible tube, cured resin and individual tube can be cut.

Furthermore, the individual tube in the method of the present invention can be removed from the cured resin after the reaction-curable resin liquid is cured.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a cable laying pipe formed by the present invention. Reference numeral 1 is a main pipe, and an existing pipe line buried in the ground is used as it is.

Reference numeral 2 is an airtight layer, and a flexible plastic tube or pipe is used. It is also possible to use a tubular woven or non-woven fabric having an airtight plastic tube attached to the inner surface.

The airtight layer 2 may be adhered to the main pipe body 1 with an adhesive, but it does not matter if it is adhered only along the inner surface of the main pipe body 1 without being adhered. Absent.

The inside of the airtight layer 2 is filled with a resin 3 obtained by curing a reaction-curable resin liquid, and the resin 3 is provided with a plurality of cables along the length direction of the main pipe body 1. A through hole 4 for insertion is formed.

The cable insertion through-hole 4 is simply made of resin 3.
However, it is preferable that the inner surface of each cable insertion through hole 4 be lined with an individual tube 5 as shown in the drawing.

The individual tube 5 is suitably a plastic tube or a tubular fiber material reinforced with the same, and the individual tube 5 is preferably adhered to the inner surface of the cable insertion through hole 4.

Next, FIG. 2 shows an embodiment in which a cable laying pipe is formed by the method of the present invention.

In FIG. 2, 1 is a main tube, and 6 is a reversing airtight tube. One end of the reversing airtight tube 6 is fixed in an annular shape at an upper part outside one end of the main tube 1. ing.

When pressure is applied by the reaction-curable resin liquid 7 to the rear portion of the annular fixing portion of the reversing airtight tube 6, the reversing airtight tube 6 is placed inside the folded portion 8 formed in the annular fixing portion. The folded-back portion 8 moves forward while reversing so as to be outside.

When the folded-back portion 8 is guided into the main pipe body 1, the folded-back portion 8 advances in the main pipe body 1 from one end to the other end, while the reversing airtight tube 6 is filled with the reaction-curable resin liquid 7. Due to the pressure, the inside of the folded-back portion 8 is sequentially inverted so that the inside is the outside.

At this time, by applying an adhesive to the inner surface of the non-inverted reversing airtight tube 6, the reversing airtight tube 6 is turned over by the reversing of the reversing airtight tube 6. It is located on the outer side of, and the airtight tube 6 for inversion and the main tube body 1 can be bonded to each other.

As a means for advancing the folded-back portion 8, the string-shaped elongated member 10 is previously inserted into the airtight tube 6 for inversion over its entire length, and as shown in FIG. By pulling the string-like elongated object 10 protruding from the folded-back portion 8 of the sex tube 6 through the main pipe body 1, the folded-back portion 8 can be advanced.

In this case, the pressure applied by the reaction-curable resin liquid 7 acting on the folded-back portion 8 may be a pressure sufficient to press the reversing airtight tube 6 onto the inner surface of the main tubular body 1, and the reversing It is not necessary to exert sufficient pressure to positively flip the airtight tube 6.

A plurality of individual tubes 5 are connected to the other end of the reversing airtight tube 6. Then, the reversing airtight tube 6 is reversed at the folded portion 8, and the unreversed reversible airtight tube 6 has already been reversed as the folded portion 8 advances in the main pipe body 1. The individual tube 5 is subsequently drawn in.

Then, the reversing airtight tube 6 is turned over for almost the entire length thereof, and the other end of the reversing airtight tube 6 reaches up to the front end of the main pipe body 1, whereby each individual tube 5 Also, it is inserted over the entire length in the reversing airtight tube 6 which has already been turned over.

In this state, the reaction-curable resin liquid 7 is reactively cured while holding the individual tube 5 in a circular cross-section, so that the reversible airtight tube 6 for reversing is placed on the inner surface of the main tube body 1 to form an airtight layer. 2 and the cured reaction-curable resin liquid 7 forms the resin 3 filled in the reversing tube 2, and the individual tube 5 becomes the cable insertion through hole 4
A cable laying pipe disposed on the inner surface is formed.

The individual tube 5 may be removed after the reaction-curable resin liquid 7 has hardened, leaving only the cable insertion through hole 4.

As the individual tube 5, a reaction-curable resin liquid 7 for advancing inside out of the airtight tube 6 for reversal
By using an external pressure-retaining material that can withstand the external pressure equivalent to the
The reaction-curable resin liquid 7 can be cured while maintaining the circular cross section of the individual tube 5 without taking any special measures.

When a tube having no external pressure shape retention property is used as the individual tube 5, the reversing airtight tube 6 is completely turned over and the individual tube 5 is inserted into the reversing airtight tube 6. After that, it is preferable to cure the reaction-curable resin liquid 7 while feeding a pressure fluid into the individual tube 5 to expand it into a circular cross section.

In the method of the present invention, the reaction-curable resin liquid 7 filled between the inverted airtight tube 6 for reversing and the individual tube 5 inserted therein is the main tube body 1.
It is also possible to cut the reversing airtight tube 6 and its internal structure at the end of the main pipe body 1 after it has hardened over the entire length of, but the cutting time can be shortened and the construction time can be shortened by the following operation. Can be shortened.

That is, after the turning over of the reversing airtight tube 6 and the insertion of the individual tube 5 are completed, the heater 9 attached to the end of the main tube 1 causes the main tube 1 and the reversing airtight tube 6 to pass through. By heating the reaction-curable resin liquid 7 therein, the curing of the reaction-curable resin liquid 7 at the relevant portion is promoted.

As a result, the reaction-curable resin liquid 7 at both ends of the main pipe body 1 has been cured, so that the reversible airtight tube 6, the cured reaction-curable resin liquid 7 and the individual tube 5 are cut at that location. be able to.

At this time, in most of the central portion of the main pipe 1 excluding both ends, the reaction-curable resin liquid 7 is uncured and retains fluidity, but the already-cured reaction-cured resin liquid at both ends is cured. The mold resin liquid 7 serves as a plug to prevent the uncured reaction-curable resin liquid 7 from flowing out and to allow cutting.

Then, with the working time for adjusting the terminals and the lapse of sufficient time thereafter, the reaction hardening type resin liquid 7 inside is also hardened, and a cable laying pipe filled with the hardened resin 3 is obtained over the entire length. Be done.

In the above embodiment, the heater 9 attached to the main pipe 1 is used for heating, but it is also possible to use other suitable means such as blowing hot air or steam instead.

[0041]

In the cable laying pipe formed according to the present invention, since the airtight layer 2 is arranged on the inner surface of the main pipe body 1, even when the main pipe body 1 is damaged, the damage is caused by the airtight layer 2. It is possible to prevent the outflow of the resin 3 and the inflow of groundwater.

A plurality of cables can be individually arranged by inserting a cable of a communication line or a power line into the cable insertion through hole 4 or the individual tube 5 arranged on the inner surface thereof.

In the method for forming a cable laying pipe of the present invention, the reversing airtightness is reversed by inserting the reversing airtight tube 6 into the main pipe body 1 while reversing it with the pressure of the reaction-curing resin liquid 7. The tube 6 adheres to the inner surface of the main pipe 1 to form the airtight layer 2, and the damaged portion of the main pipe body 1 is repaired.

As the reversing airtight tube 6 is turned over, a plurality of individual tubes 5 connected to the other end of the reversing airtight tube 6 are drawn into the reversing airtight tube 6 and the individual tubes 5 and airtight tube 6 for inversion
The space between and is solidified with the reaction hardening type resin liquid 7, and the individual tube 5 is fixed.

[0045]

According to the cable laying pipe formed according to the present invention, therefore, the damaged portion of the main pipe body 1 is repaired by the airtight layer 2, and the cable insertion through hole 4 through which the cable is to be inserted is formed in the main pipe body 1. Since it is fixed with respect to, the operation of inserting the cable into the cable insertion through hole 4 can be easily performed.

Further, by disposing the individual tube 5 on the inner surface of the cable insertion through hole 4, the cable insertion through hole 4 is formed.
The inner surface of the cable can be made smooth, and the cable can be inserted more smoothly and easily.

According to the method of the present invention, the airtight tube 6 for reversal is inserted into the elongated main tube 1 to form the airtight layer 2 in one step, and the airtight tube 6 for reversal is formed. By inserting the individual tube 5 and filling the reaction-curable resin liquid 7 between the individual tube 5 and the reversing airtight tube 6 and curing the reaction-curable resin liquid 7, the present invention can be easily performed. It is possible to form a cable laying pipe.

According to the second aspect of the present invention, since the reversing airtight tube 6 is advanced by pulling the string-like elongated object 10, the reaction curable resin that acts in the reversing airtight tube 6 is used. As the pressure of the liquid 7, the head pressure between the annular fixing portion and the folded portion 8 can be used, and the work is easy because no means for pressurizing or a sealing means for holding the pressure is required. .

Further, according to the invention of claim 5, after inserting the reversing airtight tube 6 and the individual tube 5 into the main pipe body 1, only the reaction-curable resin liquid 7 at both ends of the main pipe body 1 is cured early. By doing so, cutting can be performed without waiting for the curing of the reaction-curable resin liquid 7 inside, and the construction time can be shortened.

[Brief description of drawings]

FIG. 1 shows an example of a cable laying pipe formed according to the present invention, in which (a) is a central longitudinal sectional view and (b) is
FIG.

FIG. 2 is a central longitudinal sectional view showing a state in which a cable laying pipe is formed by the method of the present invention.

[Explanation of symbols]

1 main body 2 Airtight layer 3 resin 4 Cable insertion hole 5 individual tubes 6 Airtight tube for inversion 7 Reaction curable resin liquid 8 Folding part 9 heater 10 Long string

Claims (6)

(57) [Claims] 1. An end of an airtight tube for inversion (6) is fixed in an annular shape at one end of a main pipe body (1), and a pressure is applied to a rear portion of the annular fixing portion by a reaction hardening type resin liquid (7). Then, in the folded portion (8) formed in the annular fixing portion, the folded airtight tube (6) is inverted so that the inside is the outside, and the folded portion (8) is inside the main pipe body (1). And the reaction hardening type resin liquid (7) is formed in the airtight layer (2) while forming the airtight layer (2) by the inverted airtight tube (6) on the inner surface of the main tubular body (1). A plurality of individual tubes (5) that are filled and connected to the other end of the reversing airtight tube (6) as the reversal of the reversing airtight tube (6) progresses It is pulled in, and is turned inside out over the entire length of the main pipe (1). The reversing airtight tube (6) is inserted, the plurality of individual tubes (5) are inserted into the reversing airtight tube (6), and the reversing airtight tube (6) and the individual tube (5) are inserted. ) Is filled with the reaction-curable resin liquid (7), and the reaction-curable resin liquid (7) is cured in a state in which the individual tubes (5) each have a cylindrical shape. A method of forming a cable laying pipe, characterized in that 2. A fold-back portion (8) of the reversing airtight tube (6), wherein a long string-like object (10) is inserted through the entire length of the reversing airtight tube (6). 4. The formation of the cable laying pipe according to claim 3, characterized in that the folded portion (8) is advanced by pulling a string-like elongated object (10) protruding from the main pipe body (1). Method 3. The reaction-curable resin liquid (7) is cured in a state where the individual tube (5) is expanded in a cylindrical shape by applying a fluid pressure to the individual tube (5).
Method for forming the cable laying pipe described in 4. The individual tube (5) has an external pressure shape-retaining property such that the individual tube (5) is not easily crushed by the external pressure of the reaction-curable resin liquid (7). Method for forming a cable laying pipe according to 4 5. The reversing airtight tube (6) is inserted over substantially the entire length of the main pipe body (1), and the individual tube (5) is inserted in the reversing airtight tube (6). In this state, both ends of the main pipe body (1) are heated from the outside of the reversible airtight tube (6) to cure the reaction-curable resin liquid (7) at the relevant location, and then the reversible airtightness is provided at the relevant location. A method for forming a cable laying pipe according to claim 3, 4, 5 or 6, characterized in that the flexible tube (6), the cured resin (3) and the individual tube (5) are cut. 6. After the reaction-curable resin liquid (7) is cured,
The method for forming a cable laying pipe according to claim 3, 4, 5, 6 or 7, wherein the individual tube (5) is removed from the cured resin (3).