JP2003065463A - Pipeline regenerative pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight and easy to handle synthetic resin conduit body provided with flexibility and softness demanded in a pipeline regenerative pipe and of a form provided with gas barrier performance. SOLUTION: The conduit body comprises an inner pipe 1 and an outer pipe 2. The outer pipe 2 is formed into a spiral corrugated shape by a resin material superior in gas barrier performance. The inner pipe 1 is cylindrically formed of a synthetic resin raw material and it is adhered to inner circumferential faces of trough parts in the spiral corrugated shape of the outer pipe 2. A spiral slit 12 with the same pitch as the spiral corrugated shape of the outer pipe 2 is provided in portion excluding adhered parts 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin pipe formed on inner and outer double walls of an inner pipe and an outer pipe. More specifically, gas leaks, etc. should be inserted inside existing pipes that have a short period of safe use, such as city gas supply pipes buried underground and gas pressure pipes piped in chemical plants. The present invention relates to a pipe body for pipe line rehabilitation, which is suitable for use to prevent the occurrence of the above.

[0002]

2. Description of the Related Art When a gas pipeline is rehabilitated using this type of pipeline rehabilitation pipe, there is a portion of the gas pipeline that is installed at a right angle. In order to facilitate the above, it is essential to have considerable flexibility. As this tubular body, it is conceivable to use a commercially available synthetic resin tube having an inner and outer double wall that is widely used.

[0003]

However, in the case where the commercially available pipe is a PVC resin pipe, even if the pipe wall is a double wall pipe, as an air supply pipe for gas to be fed under internal pressure, There is a problem that it cannot be used as a rehabilitating pipe for gas pipelines due to its poor physical properties as a gas barrier. It has a problem that it is difficult to insert the pipe into the section.

Therefore, the present invention is intended to solve the above problems, and is a pipe which has the flexibility and flexibility required for a pipe rehabilitation pipe, is lightweight, and is easy to handle.
Furthermore, a tubular body having a gas barrier function is proposed here.

[0005]

The structure of the present invention, which was devised to achieve the above object, will be described with reference to the reference numerals used in the drawings showing the embodiments. The outer tube 2 is formed of a resin material having excellent gas barrier performance into a spiral undulating corrugated shape, the inner tube 1 is formed of a synthetic resin material into a substantially cylindrical shape, and the trough portion of the spiral undulation waveform of the outer tube 2 is formed. The outer peripheral surface of the outer tube 21 is bonded to the inner peripheral surface of the outer tube 21, and a spiral slit 12 having the same pitch as that of the spiral corrugated waveform of the outer tube 2 is provided on a portion other than the bonded portion 11.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention has such a structure. In carrying out the present invention, not only is the outer tube 2 formed of a continuous wall body but also the outer tube 2 itself. The structure itself is a non-continuous wall and is continuous through a part 13 of the inner pipe 1, or the outer pipe 2 is formed of nylon resin having excellent gas barrier properties. be able to. In addition, it is preferable from the viewpoint of wear resistance that the outer wall of the outer tube 2 is made thicker than the inner wall of the inner tube 1.

In addition to the nylon resin, polyamide, ethylene-vinyl alcohol copolymer, polyvinylidene chloride copolymer, and fluorine can be used as the resin material having excellent gas barrier properties for forming the outer tube 2 according to the present invention. , Polyethylene terephthalate, polyacrylonitrile, etc.
It is preferable to selectively use these resins.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are drawings showing a pipe rehabilitation pipe of a main embodiment of the present invention, and FIG. 1 shows an outer shape and a cross-sectional shape by longitudinally cutting an upper half portion of a pipe body. 2 and 3 are enlarged cross-sectional views of the cross section of the tubular body.

The pipe rehabilitation pipe P shown in this embodiment is made of a synthetic resin material as a whole, and
As can be seen from No. 2, it is a tubular body having an inner and outer double wall composed of an inner tube 1 formed in a substantially cylindrical shape and an outer tube 2 formed in an uneven spiral wave shape.

Thus, the inner tube 1 shown in the embodiment is formed of a soft nylon resin material by forming a band material 10 in which the left and right side edge portions are flattened in cross section and are successively thinned. On the core material, the left and right side edge portions are spirally wound while being polymerized in a non-adhered state to form a substantially smooth cylindrical body. In this way, the inner tube 1 having the spiral slit 12 between the overlapping portions of the strip 10 is formed.
As a means for bringing the overlapped portion of the strip 10 into the non-adhesive state, the strip 10 produced at room temperature in advance may be used, or the extruded strip may be wound while being cooled to a required temperature. .

As the outer tube 2, nylon # 12 having excellent gas barrier performance is selected, and a band material 20 made of this resin material and having a substantially U-shaped cross-section is used as a tube forming core. The material is extruded and formed by an extruder disposed on the side of the material, and both side edges 2a and 2b of the material 20 are spirally wound while being polymerized with each other on the widthwise intermediate portion of the inner tube forming material 10. It is rotated, and the superposed surfaces are fused together to be integrated, and at the same time, the inner tube forming strip 10 is also fused between the superposed surfaces 11 or is adhered via an adhesive,
The outer tube 2 having a spiral corrugated shape is formed.

In this way, the outer tube 2 has a spirally corrugated shape, the inner tube 1 has a substantially cylindrical shape, and inside the mountain portion 22 of the outer tube 2,
The inner and outer double tubes having a structure in which the spiral slit 12 is formed in the inner tube 1 are formed.

In the pipe rehabilitation pipe P having such a structure, the outer pipe 2 bears the deformation resistance against external pressure, and the inner pipe 1 guarantees a smooth flow of the internally flowing gas, but the pipe bends. At times, the inner tube 1 can be freely bent and deformed at the slit 12, and the outer tube 2 is less likely to be bent and deformed. Therefore, the outer tube 2 can be relatively freely and independently bent and deformed. It has the advantage that bent pipes can be easily used.

With respect to nylon # 12 constituting the outer tube 2 shown in the example, a city gas permeability test was conducted in a sheet state. The test results are shown in Table 1.

[0015]

[Table 1]

According to the results of this gas permeation test, the tube formed using nylon # 12 as the tube forming material as in the above example was inserted into the aged city gas pipeline,
It was confirmed that when used as a pipe rehabilitation pipe, it could exhibit sufficient gas barrier performance.

3 and 4 show other embodiments of the pipe rehabilitation pipe P, respectively. The rehabilitation pipe P shown in FIG. 3 forms the inner pipe 1 described in the first embodiment. The cross-sectional shape of the strip 10 to be formed is a simple flat strip in which the left and right side edge portions are vertically formed, and the side tube portions are spirally wound while abutting each other in a butt shape to form the inner pipe 1 It has a tubular structure in which is formed. Further, the outer tube 2 has a trapezoidal concavo-convex shape in which the bottoms of the valleys 21 are flat and the peaks of the peaks 22 are also flat. The other points are the same as the tube structure in the first embodiment.

The pipe rehabilitation pipe P shown in FIG. 4 is a pipe body in which the outer pipe 2 itself is a discontinuous wall body and is continuous through a part 13 of the inner pipe 1. An example is shown in which the lateral width of the strip 20 forming the outer pipe 2 described in the first embodiment is formed to be shorter than the lateral width of the strip 10 forming the inner pipe 1, Strip 1 forming 1
0 on the outer peripheral surface of the strip 20 on both side edges 2a, 2b.
The outer tube 2 is formed by spirally winding them with a slight distance between them and fusion-bonding only the inner tube forming band material 10. In the tube body having such a structure, the part 13 of the inner pipe located between the both side edge portions 2a and 2b of the outer pipe forming band member 20 formed in the valley portion 21 of the outer pipe 2 against the bending external force. Since they will be opposed in a concentrated manner, the flexibility of the bent pipe will be excellent. The inner tube forming band material 10 of the tube body in this embodiment may be made of a flexible resin material in consideration of this effect. Note that the pipe P in the drawings of the embodiment is shown as the one in which the position of the slit 12 in the inner pipe 1 is formed at a position deviated to one side from the central position of the peak portion 22 in the outer pipe 2. In other respects, the structure is similar to the pipe structure shown in the second embodiment.

Although the examples considered to be typical of the present invention have been described above, the present invention has the above-mentioned constitutional requirements, achieves the above-mentioned objects of the invention, and is appropriately modified within a range having the following effects. Can be carried out.

[0020]

As is apparent from the above description, the pipe rehabilitation pipe according to the present invention is an inner-outer double pipe, and the inner pipe is formed in a substantially cylindrical shape having a slit. Since the outer tube is formed in a spiral corrugated shape, it has sufficient resistance to compressive deformation against external pressure, and the resistance of the gas passing through it can be minimized to allow smooth flow. Although it is a tube with excellent barrier properties, when bending deformation is required, the inner tube does not act as a resistance to bending deformation of the outer tube, and the outer tube is relatively free and independent. Since it can be bent and deformed, it has a remarkable advantage that it has sufficient flexibility as a whole tube and can easily be inserted into the rehabilitation tube.

[Brief description of drawings]

FIG. 1 is a cutaway front view of an upper half portion showing a first embodiment.

FIG. 2 is an enlarged sectional view of a tube wall.

FIG. 3 is a front view of an upper half cutaway showing a second embodiment.

FIG. 4 is a cutaway front view of an upper half portion showing a third embodiment.

[Explanation of symbols]

1 inner tube 10 Inner tube forming strip 11 Adhesive part 12 slits 13 Part of the inner tube 2 outer tube 20 Outer tube forming strip 21 Tanibe 22 Yamabe 2a side edge 2b side edge

Claims (3)

[Claims] 1. An outer pipe (2) comprising an inner pipe (1) and an outer pipe (2).
Is formed in a spiral corrugated shape with a resin material having excellent gas barrier performance, the inner pipe (1) is formed in a substantially cylindrical shape with a synthetic resin material, and the valley portion in the spiral corrugated waveform of the outer pipe (2) is formed. It is adhered to the inner peripheral surface of (21), and further the adhered portion (11)
A pipe rehabilitation pipe having a spiral slit (12) having the same pitch as the spiral concave-convex waveform of the outer pipe (2) except for the above. 2. The outer pipe (2) is a discontinuous wall body, and the inner pipe (1)
The conduit rehabilitation pipe according to claim 1, which is continuous through a part (13) of the above. 3. The conduit rehabilitation pipe according to claim 1, wherein the outer pipe (2) is made of nylon resin.