JPH05118478A - Flexible composite resin tube - Google Patents

Abstract

PURPOSE:To provide a flexible composite resin tube having light weight, high strength against pressure and freedom from a partial fracture. CONSTITUTION:A reinforcement strip 2 having the same cross section as a tube wall corrugation is spirally embedded in a spirally corrugated synthetic resin tube wall 1 in state where the strip 2 is partially polymerized with the tube wall 1 at crest sections 2A and 2A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is mainly used for laying underground such as drainage pipes, electric wire protection pipes and telephone line protection pipes. More specifically, it is a synthetic resin pipe wall formed in a spiral wave shape. And a flexible composite resin pipe in which a spiral strip plate made of a thin metal plate is embedded in the wall thickness.

[0002]

2. Description of the Related Art Conventionally known composite resin tubes of this type are disclosed in, for example, Japanese Utility Model Laid-Open No. 61-141889. While various tube wall cross-sectional shapes are shown in the publication, the cross-sectional shape as a common divisor has a cross-sectional structure as shown in FIG.

In FIG. 9, 01 is a synthetic resin tube wall formed in a spiral wave shape, and 02 is a thin metal plate such as a stainless steel plate having a U-shaped cross section and projecting edges 02a and 02a at its open ends. Of the pipe wall 01 and the side wall portions 01b and 01b continuous with the mountain top portion 01a of the pipe wall 01 are embedded in the reinforcement strip plate 02 with the pipe axis line extending downward. Reinforcing strips A where there is no reinforcing strip are formed in a part of each valley portion 01c of the pipe wall 01 which is buried by the protruding edges 02a, 02a of the reinforcing strips 02, 02 which are adjacent to each other in the direction.

[0004]

The conventional composite resin pipe constructed as described above is lighter and more lightweight than concrete fume pipes and cast iron pipes, which are often used as underground pipes of this type. It has excellent flexibility, is easy to transport and lay, and has the advantage that it can be configured to have a pressure resistance comparable to that of a fume tube, but it has a reinforcing cut A at the valley of the tube wall. Therefore, when it is buried in the ground in a curved shape, a static load is applied to the break A of the reinforcement,
Stress is concentrated on dynamic loads, and cracks and cracks are likely to occur.

Further, when excavating a road or excavating a buried pipe, a pickaxe or a tip blade of an excavator unexpectedly collides,
There was a risk of breaking through the cut portion A. The present invention has been made in view of the above circumstances, is lightweight, and can reliably prevent local damage during excavation,
Moreover, it has an object to provide a flexible composite resin pipe which is superior in flexibility and easily laid and the like as compared with one having equivalent pressure resistance.

[0006]

The flexible composite resin tube according to the present invention is the one described in detail at the beginning, in which a strip-shaped plate made of a thin metal plate having at least two crests is used. The reinforcing strip plate is formed by spirally winding so as to polymerize inside and outside, and the reinforcing strip plate is covered with a spiral wave-shaped synthetic resin.

[0007]

According to the flexible composite resin pipe of the present invention, the entire pipe wall has a spiral wave shape, and the strip made of a thin metal plate is provided at the top of the pipe wall where earth pressure or the like is strongest. By being buried in the entire wall without interruption in a state of overlapping, the pressure resistance is high despite being light, and even if the tip of the pickaxe collides during excavation etc., that part will be punctured. There is no. In addition, since there is a marked difference in flexibility between the valley portion and the crest portion of the pipe wall where the strips do not overlap doubly, the entire pipe is excellent in flexibility despite its large pressure resistance.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show one embodiment of the present invention, in which 1 is a pipe wall made of synthetic resin formed in a spiral wave shape with an arcuate cross section, and 2 is a middle wall thickness of the pipe wall 1. It is a spiral reinforcing strip made of a thin metal plate such as a stainless steel plate embedded in the part.

As shown in FIG.
The strip-shaped plate 2A obtained by roll-forming the two arc-shaped peaks 2a, 2a and the arc-shaped valleys 2b located between them is formed so that the peaks 2a, 2a of ones adjacent to each other in the spiral axis direction are closely superposed inside and outside It is formed by spirally winding.

As shown in FIG. 3, synthetic resin strips 1A, 1A having the same thickness are sequentially wound on the inner peripheral surface and the outer peripheral surface of the above-mentioned spiral reinforcing strip 2 so that both side edges thereof are superposed on each other. The synthetic resin pipe wall 1 is formed by coating twice and heat-sealing the polymerized side edges. The band-shaped plate 2A may be a punching metal having a large number of small holes, a flat plate having no small holes, or small holes formed only on the peaks that are polymerized inside or outside, or only on the valleys. Then, the inner and outer synthetic resin bands 1A and 1A may be integrated through the small holes.

FIG. 4 and subsequent figures respectively show other embodiments of the present invention, and only the differences from the above embodiments will be described. In the embodiment shown in FIG. 4, the resin portion 1B exists between the crests 2a, 2a of the strip-shaped plate 2A that is polymerized inside and outside.
The synthetic resin strips 1A and 1A covering the entire strip 2A are spirally wound so that one peak portion is superposed inward and outward, and the superposed portion is heat-sealed.

In the embodiment shown in FIG. 5, the overlapped positional relationship between the peaks 2a, 2a of the strip plate 2A is alternately reversed inside and outside along the axial direction. In the embodiment shown in FIG. 6, the mountain tops 2a and 2a are overlapped with each other by about half of the above embodiment.

In the embodiment shown in FIG. 7, the reinforcing strip plate 2A has a triangular corrugated cross section, and FIG. 8 has a rectangular corrugated cross section. May be Although not shown, the strip-shaped plate 2A may have three or four or more peaks.

In the described embodiment, the reinforcing strip 2 is attached to the pipe wall 1.
However, the reinforcing strip 2 may be biased toward the inside of the tube wall 1. In particular, when the reinforcing strip 2 is formed of a material obtained by laminating a synthetic resin on a metal plate, since the synthetic resin used as the metal laminate is inside the reinforcing strip 2, the pipe wall 1 is formed. It is not necessary to form the synthetic resin layer.

[0015]

As described above, according to the flexible composite resin pipe of the present invention, since the strip-shaped plate made of a thin metal plate is continuous without interruption over the entire circumference of the pipe, compared with a fume pipe or a cast iron pipe. It is lightweight and easy to handle during transportation and installation.
Even if a pickaxe, a digging blade, or the like collides unexpectedly during road digging or pipe digging, there is no risk of puncturing of the pickaxe, and it can be used safely for a long period of time.

Further, even when laid underground, the peak of the pipe wall that receives the strongest dynamic load, earth pressure, etc. is reinforced by the double metal thin strip plate, so that the pressure resistance is large,
Compared with the case of single-strength reinforcement, the flexibility of the entire pipe can be made excellent in order to obtain the same pressure resistance strength, which makes it easier to lay it in the ground.

[Brief description of drawings]

1 is a partially cutaway side view,

FIG. 2 is an enlarged side view of a reinforcing strip plate,

FIG. 3 is an enlarged vertical side view of an essential part of FIG.

FIG. 4 is an enlarged vertical sectional side view of a main part showing another embodiment,

FIG. 5 is an enlarged vertical cross-sectional side view of essential parts showing another embodiment,

FIG. 6 is an enlarged vertical sectional side view of a main part showing another embodiment.

FIG. 7 is an enlarged vertical cross-sectional side view of a main part showing another embodiment,

FIG. 8 is an enlarged vertical cross-sectional side view of essential parts showing another embodiment,

FIG. 9 is an enlarged vertical side view of a main part of a conventional example.

[Explanation of symbols]

 1 Synthetic resin pipe wall 1A Synthetic resin strip 2 Reinforcement strip 2A Strip 2a Peak 2b Valley

Claims (1)

[Claims] 1. A flexible composite resin pipe in which a spiral reinforcing strip plate made of a thin metal plate is embedded within the wall thickness of a synthetic resin pipe wall formed in a spiral wave shape. A reinforcing strip is formed by spirally winding a thin metal strip having a mountain top so that one of the mountain tops overlaps inside and outside, and this reinforcing strip is formed into a spiral wave shape. Flexible composite resin tube coated with resin.