JPH0472006B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an underdrain drainage pipe that is used by being buried underground in golf courses, wetlands, and other places, and a method for manufacturing the same.

[Conventional technology]

Traditionally, this type of drainage pipe has been
As described in Publication No.-27206, a resin tube is formed by winding a tape-like net in a spiral manner so that the side edges of the net overlap one another, and between the overlapping portions of the net in this resin tube. A structure is known in which a filter made of nonwoven fabric, glass fiber, or other woven fabric is compressed, and reinforcing strips are fused and fixed to the inner and outer peripheries of a resin tube in a threaded manner.

[Problem to be solved by the invention]

This type of underdrain drainage pipe is laid in an underdrain formed under the ground, and the muddy water that seeps into the ground is filtered by a filter and guided into the drain pipe. There are various types of soil in different places, such as muddy soil, clay, or gravel, and the above-mentioned filters made of nonwoven fabric, glass fiber, or other woven fabric cannot handle all of these soil types. .

In other words, in such filters, especially filters made of non-woven fabric, the filter is relatively thick, which increases the resistance to passage of water, and the filtration action is not only achieved through the gaps between the fibers caused by the entanglement of the fibers. Since the mesh is too fine to allow fine particles of mud to pass through, the fine particles remain and accumulate between the fibers on the surface layer of the filter, causing clogging and rendering the filter unusable in a short period of time. There was a problem with that.

Furthermore, since the resin pipe is made of net, when it is installed in an underdrain, the resin pipe is stretched and the filter is torn, causing problems such as muddy water flowing into the drain pipe and accumulating. It was hot.

In addition, woven fabric coarsely woven with narrow flat threads has been used as a filter, but since the mesh is relatively coarse, there is a risk that even sandy soil may pass through. , the pipe becomes misaligned and the inflow of sand becomes even more intense, making it unsuitable for use as an underdrain drainage pipe.

Moreover, the band-shaped tape made of such a woven fabric is wound in a spiral manner so that the end edges overlap to form a tubular body, and reinforcing strips are provided on the side edges of the tape in the outermost layer of the tubular body. If the reinforcing strip is welded together with the tape by melting the bottom of the reinforcing strip, the tape will also melt and its strength will decrease;
There were problems such as the drain pipe being unable to withstand stress such as bending during handling or construction, or external pressure after construction.

The present invention provides an underdrain drain pipe that is almost unaffected by soil quality, can be used for a long time without clogging, and a method for manufacturing the same.

[Means to solve the problem]

In order to achieve the above object, the culvert drainage pipe of the present invention has a cylindrical pipe wall formed by welding a stretched film with a split film in which fine cracks are made in the stretching direction, superimposed on each other at right angles. It has a structure in which a strip of fabric with a large number of pores is wound in a spiral manner with the side parts overlapping each other, and reinforcing strips are placed on the side edges of the overlapping part of the strip of fabric that forms the tube wall. The body is wound in a spiral manner with a low-melting point resin tape interposed therebetween, and the reinforcing strip and the side portions of the strip-shaped cloth are fixed together by melting the low-melting point resin tape. be.

In addition, as a manufacturing method for such an underdrain drain pipe, a split film is produced in which a large number of pores are formed by overlapping and welding a stretched film with fine cracks in the stretching direction at right angles to the stretched film. The fabric is formed into a band of a predetermined width, and the fabric is wound around a forming shaft in a spiral manner so that the side edges overlap one another to form the main body of the pipe. A reinforcing strip is wrapped around the overlapping side edge of the band-shaped split fabric via a low-melting point resin tape, and the reinforcing strip and the overlapping side edge of the band-shaped split fabric are fused together by melting the low-melting point resin tape. It is characterized by allowing

[Effect]

The pipe wall of this underdrain drainage pipe is made of a split cloth with many pores made of orthogonal polymerization and fusion of split films, so it is thin and the pores are formed on the pipe wall. Since there is direct communication between the inner and outer circumferential surfaces of the gravel, the resistance to water passage is extremely small, allowing muddy water in the gravel to flow quickly and easily, allowing smooth drainage and allowing fine particles of mud to pass along with the muddy water. This can eliminate the occurrence of clogging.

Furthermore, even if the pores are closed by gravel, the gravel itself exerts a filtering action, so drainage efficiency will not be reduced.

Furthermore, since the split cloth is made of stretched film,
It has very high tensile strength, so there is no risk of damage to the pipe wall even if tension is applied to the pipe when it is installed in a culvert, etc., and the reinforcement is wrapped around the outer circumference of the pipe wall in a spiral shape. The reinforcing strips maintain torsional strength and pressure resistance, and in addition, the reinforcing strips are wound in a spiral manner on the split fabric that constitutes the pipe wall via a low-melting point resin tape.
Since the reinforcing strip and the split fabric are fixed together by melting this low-melting point resin tape, it is possible to firmly bond them together without melting the split fabric, and the reinforcing strip is narrow and thick. By increasing the effective area for drainage using split cloth,
Moreover, the pressure resistance is further improved, and therefore, the above-mentioned good drainage effect can be maintained for a long period of time.

In addition, since the main body of such an underdrain drain pipe is formed by winding a strip of cloth around a forming shaft in a threaded manner so that the side edges overlap one after another, continuous production is not possible. It is possible, and moreover, by wrapping a reinforcing strip on the overlapping side edge of this band-shaped split fabric via a low-melting point resin tape, the reinforcing strip and the overlapping side edge of the band-shaped split fabric can be removed by melting the low-melting point resin tape. Since the parts are fused together, the reinforcing strip and the split fabric can be reliably and firmly integrated without melting the split fabric. The tube wall maintains the prescribed shape,
It is possible to easily manufacture an underdrain drain pipe in which a large number of pores provided in the split cloth are present at a uniform density in the length direction and the circumferential direction.

〔Example〕

Embodiments of the present invention will be explained with reference to the drawings: 1
is mainly a drain pipe, and its cylindrical pipe wall 2 has a thickness of
By making two or more split films obtained by making small cracks in the stretching direction of stretched films such as high-density polyethylene films of about 0.07 to 0.15 mm, overlapping them at right angles to each other and welding them together. It is constructed by using a band-shaped divided cloth 3 of a constant width formed by the above-mentioned method, and sequentially wrapping the band-shaped divided cloth 3 in a spiral manner so that the side edges overlap. Due to the orthogonal polymerization of split films having a large number of parallel cracks, an average mesh is formed in the tube wall 2 that communicates in an open state between the inner and outer peripheral surfaces of the tube wall 2.
Many fine rectangular pores of 1.0 mm or less 4, 4...4
is formed.

Reference numeral 5 denotes a narrow, low-melting point synthetic resin tape made of soft polyethylene or the like that melts at a lower temperature than the split cloth 3, which is wound in a spiral manner on the side edge of the strip of split cloth 3 on the outer peripheral surface of the tube wall. On one side, a reinforcing strip 6 made of hard polyethylene resin or the like having the same width and thickness as the tape 5 is overlaid and wound in a spiral manner. Molten resin is filled into the pores 4 of the split cloth 3 that is fused to the bottom surface of the reinforcing strip 6 and forms the tube wall 2, and solidified to bond the tube wall 2 and the reinforcing strip 6 together. It is something.

In addition, such a synthetic resin tape 5 may be interposed between the polymerized split fabrics 3 and 3 corresponding to the bottom surface of the reinforcing strip 6, as shown in FIGS. 3 and 4, and is the divided cloth 3 on the inner circumferential surface of the tube wall.
The synthetic resin tape 5 may be wrapped and fused to the inner surface of the synthetic resin tape 5.
By melting, a portion of the molten resin sufficiently enters into the pores 4 extending from the bottom surface of the reinforcing strip 6 to the innermost layer of the split cloth 3 and solidifies, thereby achieving even stronger adhesion.

Next, we will describe the method for manufacturing the underdrain drain pipe constructed as described above.The method of manufacturing the underdrain drain pipe constructed as described above is as follows. A split fabric is obtained by overlapping two or more films in sequence at right angles to each other and welding them together, and this split fabric is cut and formed into a band of a constant width to obtain a band-shaped split fabric 3.

As shown in FIG. 5, this band-shaped split cloth 3 is wound around a forming shaft 7 in a spiral manner.

At this time, make sure that the next band-shaped cloth part overlaps the surface of the band-shaped cloth 3 wrapped earlier by 1/2 of the width.
That is, the tube wall 2 is formed by winding it in a spiral manner, even with a pitch deviation of 1/2.

In addition, the overlap pitch of the other half-width portion of the strip-shaped cloth 3 that is wrapped around one half-width portion of the strip-shaped cloth 3 that becomes the inner layer and the other half-width portion of the strip-shaped cloth 3 that is wrapped around it and becomes the outer layer is 1 in addition to 1/2. The tube wall 2 may be formed with three or four layers, respectively, by winding the pipes in a spiral manner with a pitch of 1/3 or 1/4.

The tube wall 2 formed in this way is moved forward while being rotated in a spiral manner on the forming shaft in synchronization with the feeding of the band-shaped split cloth 3.
Following the threading of the strip-shaped split fabric 3, a narrow synthetic resin tape made of soft polyethylene or the like having a lower melting point than the split fabric 3 is applied to the side edges, that is, the ears, of the outermost layers of the strip-shaped split fabric 3 that overlap each other. 5 is wound in a threaded manner, and further, a reinforcing strip 6 made of hard polyethylene resin or the like having the same width and thickness as the synthetic resin tape 5 is wound on this synthetic resin tape 5 in a threaded manner, By heating and melting the synthetic resin tape 5, a part of the molten resin is filled into the pores 4 of the split cloth 3 and is fused to the bottom surface of the reinforcing strip 6, and solidified by cooling to form a part of the molten resin into the split cloth 3. This is to fix the reinforcing strips 6 together.

In addition, when wrapping the band-shaped cloth 3 as necessary,
Polymerized split cloth 3 corresponding to the bottom surface of the reinforcing strip 6,
The synthetic resin tape 5 may be interposed between the parts 3 and fused together, or the synthetic resin tape 5 may be wrapped and fused around the inner surface of the split cloth 3 on the inner circumferential surface of the tube wall.

The synthetic resin tape 5 is heated and melted using a molding shaft 7.
This process may be carried out immediately before supplying the material, or may be carried out after winding, and in this case, the melting process is performed at a temperature lower than the melting temperature of the reinforcing strips 6 and the split cloth 3.

In this way, when the tape 5 melts, the bottom surface of the reinforcing strip 6 and the split fabric 3 forming the pipe wall 2 are bonded and integrated via the tape 5, and the melted part of the tape piece is split. It enters and fills the pores 4 of the cloth 3, solidifies in that state, and enables strong adhesion without melting the divided cloth 3.

The underdrain drain pipe manufactured in this way is drawn into the underground drain and laid to perform the above-mentioned drainage function.

〔Effect of the invention〕

As described above, according to the underdrain drainage pipe of the present invention, the pipe wall is composed of a split cloth having a large number of pores made of orthogonal polymerization and fusing of split films. Since the thickness is thin and the pores are in direct communication between the inner and outer peripheral surfaces of the pipe wall, the resistance to water passage is extremely small, and muddy water other than sand and gravel in the earth and sand can be quickly and easily transferred into the pipe through the pores. Therefore, rapid and smooth drainage is possible, and drainage efficiency is significantly improved compared to conventional drainage pipes made of non-woven fabric, etc., and fine particles of mud can also pass through the pores along with the muddy water. This eliminates the occurrence of clogging, and there is almost no decrease in drainage capacity even after long-term use.

Furthermore, even if the pores are closed by gravel, the gravel itself exerts a filtering action, so there is almost no risk of deterioration in drainage efficiency.

Furthermore, since the split cloth is made of stretched film,
The tensile strength is extremely high, so even if a tensile action occurs on the pipe when it is drawn into a culvert, the pipe wall is unlikely to be damaged, and in addition, reinforcing strips are screwed around the outer periphery of the pipe wall. Since the reinforcing strips are wrapped in a shape, the reinforcing strips can maintain sufficient torsional strength and pressure resistance.
This reinforcing strip is wound in a spiral manner onto the split cloth that constitutes the pipe wall via a low-melting point resin tape, and the reinforcing strip and the split fabric are fixed together by melting the low-melting point resin tape. Therefore, it is possible to firmly fix the two without melting the split cloth, and it is also possible to use narrow and thick reinforcing strips to increase the effective drainage area by the split cloth, and,
The pressure resistance is further improved, and therefore a good drainage effect can be maintained for a long period of time.

In addition, in order to manufacture such an underdrain drainage pipe, the main body of the pipe is formed by winding a strip of cloth onto a forming shaft in a threaded manner so that the side edges overlap one after another. , it is easy to carry out continuous production and is suitable for mass production, and furthermore, by wrapping a reinforcing strip on the polymerized side edge of this band-shaped divided cloth via a low-melting point resin tape, the low-melting point resin tape can be produced easily. The reinforcing strip and the overlapping side edge of the split fabric are fused together by melting, so the reinforcing strip and the split fabric can be reliably and firmly integrated without melting the split fabric. The pipe wall made of split cloth maintains a predetermined shape due to the reinforcing strips wrapped in a spiral shape.
It is possible to easily manufacture an underdrain drain pipe with good drainage efficiency in which a large number of pores provided in the split cloth are present at a uniform density in the lengthwise and circumferential directions.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a simplified partially sectional front view, FIG. 2 is a partially enlarged sectional view, and FIGS. 3 and 4 show another embodiment of the present invention. FIG. 5 is an enlarged sectional view showing an example, and FIG. 5 is a front view showing the manufacturing method. 1... Drain pipe main body, 2... Pipe wall, 3... Band-shaped split cloth, 4... Pore, 5... Low melting point resin tape, 6
... Reinforcement strip, 7 ... Shaft for forming.

Claims (1)

[Scope of Claims] 1. A cylindrical tube wall formed by splitting a stretched film with a large number of pores by overlapping and welding a stretched film with fine cracks in the stretching direction at right angles. It has a structure in which cloth is wound in a spiral manner with the side portions overlapping each other, and a reinforcing strip is screwed onto the side edge of the overlapping portion of the band-shaped divided cloth that formed the tube wall via a low-melting point resin tape. An underdrain drainage pipe in which the reinforcing strips and the side portions of the strip-like cloth are fixed together by the melting of this low-melting point resin tape. A split film with fine cracks in the stretching direction is stacked and welded at right angles to form a split film with many pores, and this split film is shaped into a band of a predetermined width. The strip-shaped fabric is wound onto a molding shaft in a spiral manner so that the side portions are sequentially overlapped to form the main body of the tube, and a low-melting point resin tape is applied on the overlapping side edges of the strip-shaped fabric. A method for producing an underdrain drainage pipe, which comprises wrapping a reinforcing strip through the tape, and fusing the reinforcing strip and an overlapping side edge of a strip of cloth together by melting the low melting point resin tape.