JP2020093550A - Method for producing corrugated composite tube - Google Patents

Abstract

To produce a method for producing a corrugated composite tube capable of obtaining a corrugated composite tube in which pasting between a tubular body and a covered body is suppressed.SOLUTION: Provided is a method for producing a corrugated composite tube 1 comprising: a sheet member arrangement step (104) where a sheet member S is arranged at the outer surface of a tubular body 2 formed into a tubular shape; a covering step (105) where the outer surface of the sheet member S arranged in the tubular body 2 is covered with a molten material M1 for covering to form a covered body 3; and a corrugating step (106) where a waveform continuous to the axial direction of the tubular body 2 is formed at the covered body 3.SELECTED DRAWING: Figure 2

Description

The present invention relates to a method for manufacturing a corrugated composite pipe.

The conventional method of manufacturing a corrugated composite pipe is to make the outer layer side of the inner layer (tubular body), the intermediate layer and the outer layer coextruded in the mold adhere to the die surface, thereby causing the outer layer to be corrugated. There is a method of manufacturing a corrugated composite tube having a coating (for example, refer to Patent Document 1).

JP, 2004-322583, A

In such a corrugated composite pipe, it is possible to protect the inner layer by covering the inner layer (tubular body) with the intermediate layer and the outer layer, but when connecting only the inner layer to a joint, etc. And the outer layer must be locally removed or axially shrunk.

However, in the conventional manufacturing method, since a plurality of molding materials are co-extruded to form a multilayer structure in advance, when all layers are integrated (adhered), the intermediate layer and the outer layer enclosing the inner layer serve as a covering body, and the inner layer It was difficult to remove it locally or shrink it axially.

An object of the present invention is to provide a method of manufacturing a corrugated composite pipe, which can obtain a corrugated composite pipe in which sticking between a tubular body and a covering body is suppressed.

The method for producing a corrugated composite pipe according to the present invention is a sheet member disposing step of disposing a sheet member on the outer surface of a tubular body formed in a tubular shape, and an outer surface of the sheet member disposed on the tubular body, The method includes a coating step of coating with a molten coating material to form a coating body, and a corrugating step of forming a continuous wave shape in the coating body in the axial direction of the tubular body.
According to the corrugated composite pipe manufacturing method of the present invention, it is possible to provide a corrugated composite pipe manufacturing method capable of obtaining a corrugated composite pipe in which sticking between the tubular body and the covering body is suppressed. .

In the method for manufacturing a corrugated composite pipe according to the present invention, the tubular body may be formed from a molten molding material, and the curing may be completed before the sheet member disposing step. .
In this case, it becomes easy to manufacture the corrugated composite pipe in which sticking between the tubular body and the covering body is suppressed.

In the method for manufacturing a corrugated composite pipe according to the present invention, the tubular body may be formed from a molten molding material, and the curing may be completed after the corrugating step is completed. .
In this case, the tubular body to the corrugated composite pipe can be continuously formed, and the production efficiency can be improved.

In the method for manufacturing a corrugated composite pipe according to the present invention, it is preferable that the sheet member is made of foamed resin.
In this case, it is possible to manufacture a corrugated composite tube having excellent resistance to external force while suppressing sticking between the tubular body and the covering body.

In the method for manufacturing a corrugated composite pipe according to the present invention, it is preferable that, in the sheet member arranging step, the surface temperature of the tubular body is set to a temperature lower than a melting temperature of the sheet member.
In this case, the sheet member does not melt due to the surface temperature of the tubular body, so that sticking between the tubular body and the covering body can be suppressed.

In the method for manufacturing a corrugated composite pipe according to the present invention, it is preferable that, in the coating step, the molten coating material forming the coating body has a temperature higher than a melting temperature of the sheet member.
In this case, the coating material can be welded to the sheet member, and the coating body can be easily integrally molded.

According to the corrugated composite pipe manufacturing method of the present invention, it is possible to provide a corrugated composite pipe manufacturing method capable of obtaining a corrugated composite pipe in which sticking between the tubular body and the covering body is suppressed. it can.

It is a partial side view showing an example of a corrugated compound pipe which can be manufactured using a manufacturing method of a corrugated compound pipe concerning one embodiment of the present invention in a partial section. It is a system diagram showing an example of a manufacturing system used for a manufacturing method of a corrugated compound pipe concerning one embodiment of the present invention. It is a partial perspective view which shows an example of the concrete means used for the sheet member arrangement|positioning process in the manufacturing system of FIG. FIG. 3 is a partial cross-sectional view showing an example of specific means used in a coating process in the manufacturing system of FIG. 2. It is sectional drawing which shows an example of the concrete means used for the corrugation process in the manufacturing system of FIG. It is sectional drawing which shows an example of the concrete means used for the manufacturing process of the tubular body applicable to the manufacturing system of FIG.

Hereinafter, a method for manufacturing a corrugated composite pipe according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a corrugated composite pipe having a three-layer structure that can be manufactured by using the corrugated composite pipe manufacturing method according to an embodiment of the present invention. The corrugated composite pipe 1 has a main body pipe (tubular body) 2 and a covering body 3 that covers the main body pipe 2. For example, when connecting to a joint or the like, the direction of the axis O of the main body pipe 2 ( Hereinafter, only the main body tube 2 is used by contracting it in the "axial direction"). The main body tube 2 is made of resin or the like. In this example, the main body pipe 2 is a polybutene pipe.

The cover 3 has a wave shape continuous in the axial direction. In this example, the main body tube 2 is surrounded around the axis O and is undulated in a corrugated shape along the axis O to form a bellows shape. The cover 3 has a sheet layer 3 a and a surface layer 3 b, and extends along the axial direction of the main body tube 2.

The sheet layer 3a of the cover 3 is a buffer layer including a sheet member S described later. In the present embodiment, the sheet member S that surrounds the main body tube 2 around the axis is formed into a bellows shape by undulating the corrugated shape along the axial direction. Examples of the sheet member S include non-woven fabric, foamed resin, and glass wool. Examples of the foamed resin include crosslinked polyethylene, non-crosslinked polyethylene (in this case, it is preferable to protect the outer peripheral surface of the sheet member S with another layer such as a PET film), and polyurethane. In this example, the sheet member S is made of polyethylene.

The surface layer 3b of the cover 3 covers the outside of the sheet layer 3a so as to surround the sheet layer 3a around the axis, and is integrally connected to the sheet layer 3. The surface layer 3b is made of, for example, a resin such as polypropylene (PP), polyethylene (PE), or polyamide (PA) typified by nylon. In this example, the surface layer 3b is made of polypropylene or polyethylene. The surface layer 3b is also undulated in a corrugated shape along the axial direction and formed in a bellows shape.

The cover 3 has the sheet layer 3a which is made of the sheet member S and which is not adhered to the main body tube 1, so that the covering body 3 is arranged on the outer surface of the main body tube 2 without being adhered. Therefore, the covering body 3 can be easily exposed by pressing the covering body 3 against the main body tube 2 and contracting it in the axial direction.

Next, a method of manufacturing the corrugated composite pipe 1 according to the embodiment of the present invention will be described.

The manufacturing method of the corrugated composite pipe 1 according to the present embodiment includes a sheet member arranging step of arranging the sheet member S on the outer surface of the main body pipe 2 formed in a tubular shape in a non-adhesive manner, and a main body pipe 2. A coating step of coating the outer surface of the sheet member S with a molten material to form the coating body 3, and a corrugating step of forming a continuous wave shape in the longitudinal direction of the main body tube 2 on the coating body 3. Prepare

FIG. 2 shows a manufacturing system 100 capable of realizing a method for manufacturing a corrugated composite pipe 1 according to an embodiment of the present invention.

Reference numeral 101 is a main body tube supply unit that supplies the main body tube 2. In the present embodiment, the main body tube supply unit 101 supplies the main body tube 2 which is formed from a melted molding material M2 such as a thermoplastic material and which is then cured. In addition, when the cured main body tube 2 is wound up and stored in advance, the main body tube supply unit 101 can release the curl remaining in the main body tube 2 and straighten it. In addition, "the curing is completed" means a state in which the crystal structure has been changed and the crystal structure has become stable. Specifically, when the main body tube 2 is polybutene, it means a tubular body in which the crystal phase transition is completed from an unstable tetragonal crystal (type II) to a stable trigonal crystal (type I).

Reference numeral 102 is a sheet member supply unit that supplies the flat sheet member S. In the present embodiment, the sheet member supply unit 102 is an extrusion molding machine that extrudes foamed non-crosslinked polyethylene foam into a sheet shape. Reference numeral 103 is a cutting portion for cutting the sheet member S (in this example, non-crosslinked polyethylene foam). The cutting unit 103 cuts the sheet member S extruded from the sheet member supply unit 102 into an appropriate size.

Reference numeral 104 is a sheet member placement portion. In the sheet member placement unit 104, a sheet member placement step of placing the sheet member S on the outer surface of the main body tube 2 is executed.

The sheet member arranging unit 104 covers the main body tube 2 by arranging the sheet member S on the outer surface of the main body tube 2 in a non-adhesive manner. In the manufacturing system 100 of the present example, the sheet member disposing unit 104 has a tubular guide member 104a into which the sheet member S is inserted together with the main body tube 2, as shown in FIG. The sheet member S is introduced into the inside of the guide member 104a together with the main body tube 2 while surrounding the main body tube 2 around the axis O. Thereby, the sheet member S is arranged on the outer surface of the main body tube 2 in a non-adhesive manner, so that the sheet layer 3 a is formed on the outer side of the main body tube 2.

Next, in FIG. 2, reference numeral 105 is a coating portion for coating the outer surface of the sheet layer 3a with a molten coating material M1 such as a thermoplastic material to form the coating 3. In the coating unit 105, a coating step is performed in which the outer surface of the sheet member S coated on the main body tube 2 is coated with the molten material M1 to form the coating body 3.

In the manufacturing system 100 of this example, as shown in FIG. 4, the coating unit 105 includes an extrusion molding machine having a crosshead die 105a. In the covering portion 105, the molten coating material M1 is extruded from the direction orthogonal to the feeding direction of the body tube 2 wrapped in the sheet layer 3a, so that the outer surface of the sheet layer 3a enclosing the body tube 2 is extruded. Coating with the molten coating material M1. In the manufacturing system 100 of this example, polypropylene is used as the molten coating material M1. As a result, the covering body 3 having the sheet layer 3a that is not adhered to the main body tube 2 and the surface layer 3b bonded to the sheet layer 3a is formed on the outer surface of the main body tube 2.

Further, in FIG. 2, reference numeral 106 is a corrugating portion that forms a continuous wave shape in the covering body 3 in the direction of the axis O of the main body tube 2. In the corrugating unit 106, a corrugating process of forming a continuous wave shape in the axis O direction on the covering body 3 is performed.

The covering 3 formed by the covering portion 105 is in a semi-cured state in which the molten coating material M1 is not completely cured. In the manufacturing system 100 of this example, as shown in FIG. 5, the corrugating unit 106 has a corrugating molding machine 107. The corrugating molding machine 107 has two molds 107a and 107b. Corrugation grooves 107c are formed on the mating surface sides of the molds 107a and 107b, respectively. The corrugated groove 107c forms a cavity inside the molds 107a and 107b by clamping the two molds 107a and 107b. The cavity forms the external shape of the corrugated composite tube 1, that is, the external shape of the cover 3.

Further, in the manufacturing system 100 of this example, a vacuum device (suction device) 107d is provided on each of the molds 107a and 107b. The vacuum device 107d can suck the air in the cavity through the corrugated grooves 107c of the two molds 107a and 107b. Therefore, when the main body tube 2 provided with the covering body 3 is clamped by the corrugating molding machine 107 and then suctioned by the vacuum device 107d, only the covering body 3 which is not adhered to the main body tube 2 is corrugated groove 107c. And is pressed against the corrugated groove 107c. As a result, only the covering 3 can be formed into a corrugated shape.

As another method of pressing the covering body 3 into the corrugated groove 107c, a method of pressing the covering body 3 into the corrugated groove 107c using a pressurizing device for increasing the pressure between the main body tube 2 and the covering body 3 is used. Is mentioned. The pressurizing device may be, for example, one using a compressor as a pressure source.

As described above, when the manufacturing system 100 of FIG. 2 is operated, the sheet member arranging step, the covering step, and the corrugating step are executed, so that only the covering body 3 that is not adhered to the main body tube 2 is corrugated. The corrugated composite tube 1 can be manufactured.

The corrugated composite pipe 1 manufacturing method according to the present embodiment includes a sheet member arranging step of arranging a sheet member S on an outer surface of a main body pipe 2 formed in a tubular shape, and a sheet member S arranged on the main body pipe 2. A coating step of coating the outer surface with the molten coating material M1 to form the coating 3 and a corrugation step of forming a continuous wave shape in the direction of the axis O on the coating 3 are provided. .. According to the method for manufacturing a corrugated composite pipe 1 according to the present embodiment, it is possible to obtain the corrugated composite pipe 1 in which sticking between the main body pipe 2 and the covering body 3 is suppressed, and a method for manufacturing a corrugated composite pipe. Can be provided.

Particularly, in the method for manufacturing the corrugated composite pipe 1 according to the present embodiment, the outer shape of the main body tube 2 is formed from the molten molding material M2, and the main body tube 2 that has been cured after the outer shape is formed is Supply from the main body pipe supply unit to the sheet member arranging step. In this case, since the main body tube 2 that has been cured in advance is used for manufacturing the corrugated composite tube 1, it is easy to manufacture the corrugated composite tube 1 in which sticking between the main body tube 2 and the covering body 3 is suppressed. Become.

Further, according to the method for manufacturing the corrugated composite pipe 1 of the present invention, the main body pipe 2 is formed from the molten molding material M2, and the curing is completed after the corrugation process is completed. Can be Specifically, in the manufacturing system 100 of FIG. 2, the main body tube supply unit 101 uses an extrusion molding machine having an injection nozzle 101a as shown in FIG. From the injection nozzle 101a, the molten molding material M2 shaped into the outer shape of the main body tube 2, in other words, the main body before completion of curing, that is, the semi-cured main body tube (semi-cured tubular body) 2a, is a sheet member. It is sent to the placement unit 104. Thereby, the hardening of the molten molding material M2 that forms the main body tube 2 (hardening of the main body tube 2) is completed after the corrugation process is completed. In this case, the formation from the main body pipe 2 to the corrugated composite pipe 1 can be continuously performed, and thus the production efficiency can be improved.

In the method of manufacturing the corrugated composite pipe 1 according to the present embodiment, the sheet member S is formed of foamed resin such as polyurethane foam. In this case, it is possible to manufacture the corrugated composite pipe 1 having excellent resistance to external force while suppressing sticking between the main body pipe 2 and the covering body 3.

In the method for manufacturing the corrugated composite pipe 1 according to the present invention, in the sheet member arranging step, the surface temperature of the main body pipe 2 is set to the melting temperature of the sheet member S (for example, in LDPE (low density polyethylene), the softening point is about 80 to 100C). It is preferable that the temperature is lower than (°). As a specific example, the sheet member is formed by using either the main body tube 2 whose surface temperature has been cooled to the melting temperature of the sheet member S or less and which has been completely cured, or the main body tube 2 which has been completely cured after the corrugation process is completed. An example is a case where the placement step is executed. In such a case, since the sheet member S does not melt due to the surface temperature of the main body tube 2, sticking between the main body tube 2 and the covering body 3 (the sheet layer 3a in the present embodiment) can be suppressed.

In the method for manufacturing the corrugated composite pipe 1 according to the present invention, the surface temperature of the main body pipe 2 is changed to the melting temperature of the main body pipe 2 in at least one of all steps of the sheet member arranging step, the covering step and the corrugating step. (For example, in the case of polybutene, it is preferable to set the temperature lower than the softening point 113 to 121C° (specifically, 100°C or lower, for example). In this case, the main body tube 2 is difficult to melt and, by extension, This is effective in suppressing sticking between the main body tube 2 and the cover 3. And more preferably, the surface temperature of the main body tube 2 is set to a temperature lower than the melting temperature of the main body tube 2 in all steps of the sheet member arranging step, the covering step and the corrugating step.

Further, in the method for manufacturing the corrugated composite pipe 1 according to the present invention, it is preferable that, in the coating step, the molten material used for forming the coating body 3 has a temperature higher than the melting temperature of the sheet member. In this case, the molten material can be welded to the sheet member, and the cover can be easily integrally formed.

As described above, according to the method for manufacturing the corrugated composite pipe 1 according to the present embodiment, it is possible to obtain the corrugated composite pipe 1 in which the sticking between the main body tube 2 and the covering body 3 is suppressed. A method of manufacturing the composite pipe 1 can be provided.

The above is only one embodiment of the present invention, and various modifications can be made according to the scope of the claims. For example, in the method of manufacturing the corrugated composite pipe 1 according to the present embodiment, the sheet member S is directly supplied from the extrusion molding machine to the sheet member arranging step, but it is stored as a rolled roll sheet in advance. Alternatively, the sheet member S having a desired length may be drawn out as necessary. Further, the coating body 3 can be composed of three or more layers by using one or more molten coating materials M1 for coating the main body tube 2 in the coating step. Further, the shape of the cross section including the corrugated axis O formed in the covering body 3 is not limited to the corrugated shape formed by the curves as shown in the cross section of FIG. In this case, the cross-sectional shape can be changed to various shapes such as a wavy shape formed by straight lines (segments). Further, as shown in the cross section of FIG. 1, the corrugated shape formed on the cover 3 has a bellows shape in which large-diameter annular portions having a large outer diameter and small-diameter annular portions having a small outer diameter are alternately continuous in the axial direction. Of course, a spiral shape in which a convex portion having a large outer diameter extends while rotating around the axis in the axial direction is also included.

INDUSTRIAL APPLICATION This invention can be utilized as a manufacturing method of the corrugated composite pipe which arrange|positions a sheet member on the outer surface of a tubular body.

1; corrugated composite pipe, 2; main pipe (tubular body), 2a; semi-cured main pipe, 3; coating, 3a; sheet layer, 3b; surface layer, 100; manufacturing system, 101; main pipe supply unit, 102 Sheet member supply unit 103; cutting unit 104; sheet member arrangement unit 105; coating unit 106; corrugation unit M1; molten coating material M2; molten molding material S; sheet member

Claims (6)

A sheet member arranging step of arranging a sheet member on the outer surface of a tubular body formed in a tubular shape;
A coating step of coating the outer surface of the sheet member arranged in the tubular body with a molten coating material to form a coating body,
In the coating body, a corrugation step of forming a continuous wave shape in the axial direction of the tubular body,
A method of manufacturing a corrugated composite pipe, comprising: The method for producing a corrugated composite pipe according to claim 1, wherein the tubular body is formed of a molten molding material, and is cured before the sheet member disposing step. The method for producing a corrugated composite pipe according to claim 1, wherein the tubular body is formed of a molten molding material, and curing is completed after the corrugating step. The method for producing a corrugated composite pipe according to claim 1, wherein the sheet member is formed of foamed resin. 5. The corrugated composite pipe manufacturing method according to claim 1, wherein in the sheet member arranging step, a surface temperature of the tubular body is lower than a melting temperature of the sheet member. The method for producing a corrugated composite pipe according to claim 1, wherein, in the coating step, the molten material forming the coating body is heated to a temperature higher than the melting temperature of the sheet member.

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