JP2603598B2 - Culvert drain - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a culvert drain pipe buried in a golf course, a wetland, or other underground.

[0002]

2. Description of the Related Art Conventionally, as this type of drain pipe, as described in Japanese Utility Model Publication No. 54-27206,
The tape-shaped net is spirally wound so that the side edges thereof are sequentially overlapped to form the inner and outer layers, and a filter made of non-woven fabric or glass fiber or other woven fabric is interposed between these layers. There is known a structure in which a reinforcing strip is spirally fused and fixed to the inner and outer circumferences of a pipe.

[0003]

Such a culvert drain pipe is laid in a culvert formed under the ground, and filters muddy water that has penetrated under the ground by a filter and guides the muddy water into the drain pipe. However, there are various types of soil at the burial site of the culvert drainage pipe, for example, mud, clay or gravel, and the above-mentioned culvert drainage pipe cannot cope with all these soil qualities.

[0004] That is, the net forming the inner and outer layers of the pipe is used for the purpose of maintaining the shape and strength of the pipe. Is hardly exhibited, and the function as a filter has a structure in which only the nonwoven fabric is used. Therefore, the non-woven fabric must be relatively thick, which increases the resistance to water passage and performs a filtering action through a gap between the fibers caused by the entanglement of the fibers. This makes it difficult to pass the fine particles of the mud, and the fine particles remain and accumulate between the fibers in the surface layer of the filter to cause clogging, which makes the filter unusable in a short time.

Further, the net forming the inner and outer layers of the pipe is easily stretched by a tensile force at the time of handling or at the time of piping, and the stretching force breaks the nonwoven fabric, so that the filtering action cannot be exerted. However, there is a problem that muddy water flows into and accumulates in the drainpipe, and in addition, since the nonwoven fabric is exposed to the outside through the coarse mesh of the net, there is a possibility that the nonwoven fabric may be damaged by rubbing with earth and sand. Was.

Although a woven fabric coarsely woven by a narrow flat yarn is also used as a filter, there is a possibility that the woven cloth may pass through sand even due to the relatively coarse mesh. In addition, misalignment occurs, and the inflow of sand becomes more intense, which is not suitable for use as an underdrain drain pipe. SUMMARY OF THE INVENTION The present invention provides an underdrain drainpipe capable of exhibiting a stable drainage capability for a long period of time without being clogged, almost without being affected by soil properties.

[0007]

In order to achieve the above object, a drainage pipe of a culvert according to the present invention comprises two or more stretched synthetic resin films having a number of parallel cuts in the drawing direction, wherein the cut directions are orthogonal to each other. A polymer film having a large number of pores formed by polymerizing and fusion bonding is used as an outer layer of the tube wall, and a thin non-woven fabric having a thickness of 0.5 mm or less is polymerized integrally as an inner layer on the inner peripheral surface of the outer layer. It has a structure consisting of A reinforcing strip may be spirally wound around the outer peripheral surface of the tube.

[0008]

The outer layer of the wall of the culvert drainage pipe has a plurality of stretched films having a large number of parallel cuts, and a plurality of fine films formed by polymerizing and fusing such that the cut directions are orthogonal to each other. Since it is formed from a film, the non-woven fabric disposed as an inner layer is entirely covered and protected, and the thin non-woven fabric can be prevented from being broken by sliding contact with earth and sand, and the polymerization formed from a stretched film. The film is
Since the tensile strength is extremely high, even if the pipe is stretched in a culvert, etc., the tensile force is hardly applied to the nonwoven fabric, and therefore, the nonwoven fabric can be used for a long time. It is.

Further, the thickness of the stretched film is small, and the large number of pores formed by the intersection and polymerization of the cuts provided in the film always maintain a predetermined size and shape so that they can pass directly into the pipe. Because of the communication, the muddy water in the earth and sand can be quickly and easily circulated through the pores and the muddy water in the earth and sand can be smoothly and smoothly drained, and the fine particles of the mud can be passed together with the muddy water to eliminate clogging. In addition, even if the pores are closed by the gravel, the gravel itself exerts a filtering action, so that the drainage capacity is not reduced.

[0010] Further, the large soil particles that are going to pass through the pores are prevented from passing into the pipe by the nonwoven fabric polymerized on the inner peripheral surface side of the film provided with the pores,
Only small particles can be passed along with water. At this time, since the non-woven fabric is thin, the fine particles do not remain between the fibers of the non-woven fabric and easily pass through the pipe without clogging. If the reinforcing strip is spirally wound around the outer circumference of the pipe, the torsional strength and pressure resistance of the pipe can be maintained.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
1 and 2, reference numeral 1 denotes a cylindrical pipe wall which mainly constitutes a drain pipe, and a polymerization film 2 having a large number of rectangular pores 3, 3... Is 0.5mm,
Preferably, the nonwoven fabric 4 having a thickness of 0.2 mm or less is laminated as an inner layer and partially adhered and integrated, and the reinforcing strip 5 is spirally wound around the outer peripheral surface of the tube wall 1 at a constant pitch. It is fused and integrated.

Polymerized film 2 for forming the outer layer of the tube wall
Is generally referred to as splitting cloth and has a thickness of 0.07 to
For films such as polyethylene film of about 0.15mm,
Using a split film having a large number of cuts in the stretching direction, at least two or more films having the large number of cuts are cross-linked by polymerizing and fusing the cut direction and the stretching direction so as to be orthogonal to each other. A large number of pores 3 are formed in the portion, and the size of the pores 3 can be appropriately changed depending on the width between cuts, but it is preferably 1.0 mm or less and about 0.2 mm.

On the other hand, the porosity of the nonwoven fabric 4 forming the inner layer of the tube wall 1 is not more than half of the porosity of the above-mentioned polymerized film 2, and the nonwoven fabric 4 is formed through the pores of the pores 3 of the polymerized film 2. Is exposed.

FIGS. 3 and 4 show another embodiment of the present invention, in which the above-mentioned nonwoven fabric 4 is used as an intermediate layer of the tube wall, and the stretched polymer films 2, 2 'having a large number of pores 3 inside and outside thereof. And the tube wall 1 is formed in a state of being superposed integrally. That is, in the above-described embodiment, the polymer film 2 'is disposed on the inner peripheral surface side of the nonwoven fabric 4, and the nonwoven fabric 4 is sandwiched between the inner and outer films 2, 2'.

In order to manufacture such a drainage pipe, as shown in FIG. 5, a polymer film 2 and a non-woven fabric 4 for forming the pipe wall 1 are combined with a band-shaped film 2a having a desired width and a band-shaped non-woven fabric.
4a, the band-shaped film 2a and the band-shaped nonwoven fabric 4a can be obtained by spirally winding and integrating them on a rotational molding shaft (not shown) such that their side edges sequentially overlap.

More specifically, first, the band-shaped film 2a is first wound on the rotational molding shaft so that the film to be wound next overlaps the surface of the film to be wound once by one-half width, that is, It is spirally wound with a pitch shift of 1/2, and at this time, a narrow binder member 6 is inserted so as to overlap one end edge of the band-shaped film 2a, and the width of the band-shaped film 2a is reduced. The band-shaped nonwoven fabric 4a having a width of about 1/2 of that of the band-shaped film 2a is wrapped spirally in a state where the band-shaped nonwoven fabric 4a is overlapped on one half, and the both ends of the band-shaped nonwoven fabric 4a are melted by heating and melting the binder member 6. The tube wall is formed by being integrally bonded to the belt-like film 2a.

Further, at the time of forming the tube wall, a reinforcing strip 5 made of a thick hard polyethylene resin or the like is spirally formed at the same pitch on the other end of the band-like film 2a forming the outer layer via a binder member 7. And the binder member 7 is heated and melted to be integrally wound.

The culvert drainage pipe thus obtained has a state in which the other half of the band-shaped film 2a is coated on the band-shaped nonwoven fabric 4a to form an outer layer of the tube, and the band-shaped nonwoven fabric 4a is disposed in the middle layer. One half of the film 2a forms an inner layer, which becomes the culvert drainage pipe shown in FIG.
In the case of forming a culvert drainage pipe composed of a double layer as shown in FIG. 5, a band-shaped nonwoven fabric 4a is spirally wound on a rotational molding shaft while polymerizing and bonding both end edges thereof to each other. The band-shaped film 2a may be spirally wound around, and the right portion may be bonded to the band-shaped nonwoven fabric 4a via an appropriate band-ider. The culvert drainage pipe configured as described above is drawn and laid in the culvert below the ground, and performs the above drainage action.

[0019]

As described above, according to the culvert drainage pipe of the present invention, a plurality of stretched films having a large number of parallel cuts are polymerized and fusion-bonded such that the cut directions are orthogonal to each other. The polymer film with holes is used as the outer layer of the tube wall, and the inner layer of the outer layer is formed by integrally polymerizing a thin non-woven fabric having a thickness of 0.5 mm or less as the inner layer. Not only is it easy to handle, but it also has excellent flexibility, making piping work easier during installation.
In addition, the nonwoven fabric disposed as the inner layer is entirely covered and protected by the polymerized stretched film, so that the thinly formed nonwoven fabric can be prevented from being broken by sliding contact with earth and sand, and the polymerized film formed by the stretched film. Since the tensile strength of the film is extremely high, even if the pipe is stretched due to laying in a culvert or due to earth pressure, etc., almost no tensile force acts on the non-woven fabric, eliminating damage to the pipe wall. And can be used for a long time.

Further, the thickness of the stretched film is small, and the above-mentioned many pores formed by the intersection and polymerization of the cuts provided in the film always maintain a predetermined size and shape so that they can pass directly into the pipe. Because of the communication, the passage resistance of water is extremely small, and muddy water in the earth and sand can be quickly and easily circulated through the pores. Therefore, smooth drainage is possible, and fine particles of the mud are allowed to pass together with the muddy water and clogged. In addition, even if the pores are closed by gravel, the gravel itself exerts a filtering action,
Does not reduce drainage capacity.

Further, the large soil particles which are going to pass through the pores are prevented from passing into the pipe by the nonwoven fabric polymerized on the inner peripheral surface side of the film having the pores,
Only small particles can be passed together with water. At this time, since the nonwoven fabric is thin, the fine particles do not remain between the fibers of the nonwoven fabric and easily pass through the pipe to ensure reliable and good drainage over a long period of time. Can be played.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view of Example 1.

FIG. 2 is a partially enlarged cross-sectional view thereof,

FIG. 3 is a partially cutaway side view of Example 2.

FIG. 4 is a partially enlarged sectional view thereof,

FIG. 5 is a cross-sectional view for explaining a manufacturing method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pipe wall 2 Polymerized stretch film 3 Pores 4 Nonwoven fabric

Claims (2)

(57) [Claims] 1. A polymer film having a large number of pores formed by polymerizing and fusing two or more stretched synthetic resin films having a number of parallel cuts in the drawing direction so that the cut directions are orthogonal to each other. A culvert drain pipe comprising an outer layer of a pipe wall, and a thin nonwoven fabric having a thickness of 0.5 mm or less as an inner layer integrally polymerized on an inner peripheral surface of the outer layer. 2. The method according to claim 1, wherein the polymerization film is an inner or outer layer of a tube wall.
Underdrain pipe according to claim 1, characterized in that it is interposed as an intermediate layer the nonwoven fabric therebetween