JPH07117178B2 - Composite pipe - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a composite pipe in which a resin layer is reinforced with continuous fibers and reinforcement layers are laminated.

(Prior Art) A resin pipe is widely used because it has excellent characteristics such as being lighter in weight and not rusting as compared with a metal pipe. However, this resin pipe is inferior to the metal pipe in pressure resistance and impact resistance. Therefore, as a resin tube having pressure resistance and impact resistance, there has been proposed a composite tube in which a reinforced layer of a resin reinforced with continuous fibers is provided on the outer periphery of a thermoplastic resin tube. For example, JP-A-59-47590 and JP-B-62-773 disclose a composite pipe in which a reinforced layer of a thermosetting resin reinforced with continuous fibers is provided on the outer periphery of a thermoplastic resin pipe, Japanese Unexamined Patent Publication (Kokai) No. 63-152786 discloses a composite pipe in which a reinforced layer of a thermoplastic resin reinforced with continuous fibers is provided on the outer circumference of the thermoplastic resin pipe.

(Problems to be Solved by the Invention) However, in the above-mentioned conventional composite pipe, the thermoplastic resin or thermosetting resin reinforced by continuous fibers is simply reinforced on the outer periphery of the thermoplastic resin pipe or thermosetting resin pipe of the inner layer. Since a layer is provided, if the difference in the coefficient of linear expansion between the thermoplastic resin tube of the inner layer and the reinforced layer is large, when hot water is flowed through such a composite tube or when it is used at high temperature, the inner layer of There is a problem that peeling easily occurs at the interface between the thermoplastic resin tube and the reinforcing layer.

The present invention has been made to solve the above-mentioned problems, and its object is to have excellent pressure resistance and impact resistance, and to provide an inner layer when hot water is used or when it is used at high temperature. An object of the present invention is to provide a composite pipe in which the interface between the thermoplastic resin pipe and the reinforcing layer is hard to peel off.

(Means for Solving the Problems) The composite pipe in the present invention has a continuous fiber material arranged along the longitudinal direction of the pipe on the outer periphery of the thermoplastic resin pipe of the inner layer formed by being embedded in the pipe wall, The composite pipe is characterized in that a reinforced layer of a resin reinforced with continuous fibers is provided.

The thermoplastic resin used for the thermoplastic resin tube of the inner layer is not particularly limited as long as it can be extruded into a tubular shape, and a thermoplastic resin suitable for the purpose of use of the tube is used. For example,
Examples thereof include polyvinyl chloride, chlorinated polyvinyl chloride, polyethylene, polypropylene, polystyrene, polyamide, polycarbonate, polyphenylene sulfide, polysulfone, and polyether ether ketone. These thermoplastic resins may be used alone or as a mixture of two or more. Further, additives such as heat stabilizers, plasticizers, lubricants, antioxidants, ultraviolet absorbers, pigments, inorganic fillers, reinforcing fibers, fillers, processing aids and modifiers may be added.

As the continuous fiber material embedded in the thermoplastic resin tube,
A fiber material having a linear expansion coefficient smaller than that of the thermoplastic resin used, such as glass fiber, carbon fiber, metal fiber, or synthetic fiber such as aramid fiber or vinylon is used.

Further, when the continuous fiber material is composed of a large number of filaments, the fact that the filaments are embedded in a state in which the thermoplastic resin is sufficiently impregnated between the filaments means that the pipe is watertight,
Also, it is preferable in that the adhesiveness between the continuous fiber material and the thermoplastic resin is enhanced, and the continuous fiber material is subjected to a surface treatment such that the thermoplastic resin is previously impregnated between the filaments in order to enhance the adhesiveness with the resin. Is preferably used. In this case, the thermoplastic resin previously impregnated into the continuous fiber material does not need to be the same as the thermoplastic resin forming the thermoplastic resin tube of the inner layer, and the thermoplastic resin having high compatibility with each other and capable of being fused. If The term "fusible" as used herein means a state in which both resins are heated to a molten state and then pressure-bonded, and after cooling, the fused interface does not easily break.

A method for obtaining a continuous fiber material by impregnating a filament with a thermoplastic resin is to pass a roving-like or strand-like continuous fiber material composed of a large number of filaments through (i) a fluidized bed of powdery thermoplastic resin. How to (ii)
A method in which the powdery thermoplastic resin is impregnated between the filaments by passing through a tank of a liquid in which the powdery thermoplastic resin is dispersed and then dried, and then heated above the melting temperature to integrate the fiber and the resin. Is preferably adopted. Further, in the case of a resin having a low melting temperature, it is possible to impregnate the continuous fiber material by a method of immersing the continuous fiber material in a bath of the molten resin.

The reinforced layer provided on the outer periphery of the thermoplastic resin tube is a continuous fiber reinforced material impregnated with a resin on the outer periphery of the thermoplastic resin tube of the inner layer in which the continuous fiber material is embedded in the longitudinal direction of the extruded tube. It is obtained by winding one layer or multiple layers and then curing or melting and integrating the resin.

The continuous fiber reinforcing material used for the reinforcing layer is exemplified by the same continuous fiber material embedded in the thermoplastic resin tube.
The resin used for impregnating the continuous fiber reinforcing material of the reinforcing layer is a thermosetting resin such as unsaturated polyester, epoxy resin, imide resin, or polyvinyl chloride or chlorine used for molding the thermoplastic resin pipe. Polyvinyl chloride,
Examples thereof include thermoplastic resins such as polyethylene, polypropylene, polystyrene and polyamide. The resin used for the reinforcing layer is a thermoplastic resin that is highly compatible with the thermoplastic resin used for the thermoplastic resin tube of the inner layer and has good fusion properties, and the reinforcing layer is fused to the outer circumference of the thermoplastic resin tube of the inner layer. By providing in, the adhesiveness between the thermoplastic resin tube and the reinforcing layer is high,
A composite tube with excellent reliability can be obtained.

As a method for providing the fused reinforcing layer, a method of winding a continuous fiber reinforcing material impregnated with a thermoplastic resin while heating the thermoplastic resin tube of the inner layer, a continuous fiber reinforcing material by a heating means after winding and For example, a method of heating the thermoplastic resin tubes of the inner layer to fuse them to each other is adopted.

When the continuous fiber material and the continuous fiber material of the reinforcing layer are continuous fibers composed of a large number of filaments, it is preferable that the resin is sufficiently impregnated between the filaments. It is preferable in that a tube can be obtained.

When a thermosetting resin is used as the impregnating resin for the continuous fiber reinforcement, it is obtained by immersing roving-shaped or strand-shaped continuous fibers composed of a large number of filaments in a water tank of liquid thermosetting resin. When a thermoplastic resin is used as the resin, it can be obtained by the same method as impregnating the above continuous fiber material.

Hereinafter, a method for producing the composite pipe of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 is a sectional view of a composite pipe according to the present invention. In the figure, reference numeral 1 denotes a composite pipe, and the composite pipe 1 includes a thermoplastic resin pipe 3 as an inner layer, which is a core material in which a continuous fiber material 2 is embedded in a longitudinal direction, and a reinforcement layer 4 formed from a continuous fiber reinforcement material. It consists of and.

In FIG. 2, the continuous fiber material 2 is introduced into the resin flow path 13 from the rear of the crosshead type pipe die 12 connected to the extruder 11, and is continuously introduced into the thermoplastic resin extruded by the extruder 11. By embedding the fibrous material 2 and molding it into a tubular shape, the thermoplastic resin tube 3 of the inner layer to be the core material is formed.

Subsequently, a winding device (not shown) is rotated around the thermoplastic resin tube 3 to wind the continuous fiber reinforcing material 6, and the heating device 14 heats the continuous fiber reinforcing material 6 from the surroundings to reinforce the thermoplastic resin tube 3. Fusing material 6 to form a first reinforcing layer, and
Similarly, the continuous fiber reinforcing material 6 is wound around the outer surface and heated from the periphery by the heating device 14 to be fused to form the reinforcing layer 4 to form the composite tube 1.

Then, the extruder is introduced to the outer periphery of the reinforcing layer 4 by being guided to the coating mold 16.
A thermoplastic resin is extruded from 15 through a coating mold 16 to form an outer layer 5 on the outer periphery of the reinforcing layer 4. The hot composite pipe 1 on which the outer layer 5 is formed is subsequently cooled by a cooling device 17 such as a water tank and then taken by a take-up machine 18.

As the extruders 11 and 15, various types of extruders such as an extruder used for molding a usual thermoplastic resin pipe can be used.

As shown in FIG. 3, the continuous fiber material 2 impregnated with the thermoplastic resin is a fluidized bed 19 in which the powder of the thermoplastic resin 8 fluidizes the roving-like continuous fibers 7 made of filaments.
After passing through the inside and adhering the powdery thermoplastic resin 8 between the filaments, the mold 20 having a circular opening is drawn out, and the thermoplastic resin 8 is melted and integrated with the continuous fiber material 7. To manufacture.

As shown in FIG. 4, the continuous fiber reinforcing material 6 comprises a roving-like continuous fiber 7 made of filaments and a thermoplastic resin 8.
After passing through the fluidized bed 19 in which the powder is fluidized to adhere the powdery thermoplastic resin 8 between the filaments, the thermoplastic resin 8 is heated / pressurized by the heating roll 21.
Is melted to integrate the continuous fibers 7 into a tape.

As shown in FIG. 2, the continuous fiber reinforcing material 6 may be wound by rotating in opposite directions, and the continuous reinforcing fibers may be wound around the outer circumference of the thermoplastic resin tube 3. Is preferable, and a composite tube having excellent pressure resistance can be obtained, which is preferable. The continuous fiber reinforcement 6 is wound around the outer periphery of the thermoplastic resin pipe 3 so that no gaps or overlaps occur, and the thermoplastic resin pipe 3 and the continuous fiber reinforcement 6 are fused and integrated.

In order to prevent the thermoplastic resin tube 3 from being deformed when the continuous fiber reinforcing material 6 is wound and fused around the outer periphery of the thermoplastic resin tube 3, the inner core protruding from the resin outlet of the mold 12 in the extrusion direction. And a continuous fiber reinforcing material 6 is wound around the outer periphery of the thermoplastic resin tube 3 at a position outside the inner core, or a mold.
A method in which cooling air is blown into the thermoplastic resin tube 3 from the tip of 12 to cool the inner surface of the thermoplastic resin tube 3 and the continuous fiber reinforcing material 6 is wound may be adopted.

In the above description, an example in which the composite pipe is manufactured by continuously performing a series of manufacturing steps while being taken by a take-up machine has been described, but as shown in FIG. A reinforcing layer of continuous fiber reinforcement may be provided in a separate step on the outer periphery of the thermoplastic resin tube of the inner layer.

Further, on the outer periphery of the reinforced layer, a thermoplastic resin tube is introduced into the coating mold, and the thermoplastic resin extruded from the extruder is extrusion-coated on the outer periphery of the reinforced layer, and after providing an outer layer, cooling means such as a water tank. Although an example of manufacturing a composite pipe by cooling with
A composite pipe without an outer layer may be used. When the outer layer is provided, the thermoplastic resin used for the outer layer may be any thermoplastic resin without particular limitation, but when the resin of the reinforcing layer is a thermoplastic resin, it is used for the reinforcing layer. It is preferable to use a thermoplastic resin that has a high compatibility with the thermoplastic resin and can be fused, because a composite tube in which the reinforcing layer and the outer layer are firmly fused and integrated can be obtained.

(Operation) The thermoplastic resin tube of the inner layer is formed by embedding continuous fibers arranged in the longitudinal direction of the tube inside the tube wall, and at the outer periphery of the thermoplastic resin tube, a resin (thermoplastic resin or A reinforcing layer made of a continuous fiber reinforcing material impregnated with a curable resin) is provided, and is fused and integrated with the thermoplastic resin tube.
Therefore, the continuous fiber material suppresses the linear expansion of the thermoplastic resin tube of the inner layer, peeling is less likely to occur at the interface with the reinforcing layer, and the watertightness is excellent.

(Example) An example is described based on a drawing.

Example 1 1) Preparation of continuous fiber material in which thermoplastic resin is impregnated between filaments As shown in FIG. 3, roving glass fiber (800tex) 7 composed of filaments having a diameter of 13 μm was replaced with polyvinyl chloride resin. The powdery thermoplastic resin composition 8 containing as a main component and having a particle diameter of about 250 μm is passed through the fluidized bed 19 which is fluidized by the air 19a, and powdery heat is generated between the filaments of the glass fiber 7. After attaching the plastic resin,
A mold 20 having a circular opening with a diameter of 1 mm, which was heated to 200 ° C., was drawn out, the thermoplastic resin was melted and integrated with the glass fiber 7, and the thermoplastic resin was impregnated between the filaments of a diameter of 1 mm. Continuous fiber material 2 was prepared.

2) Preparation of continuous fiber reinforced material in which thermoplastic resin is impregnated between filaments As shown in Fig. 4, roving glass fiber (4400tex) 7 composed of filaments having a diameter of 23 µm was mixed with vinyl acetate-vinyl chloride. The powdery thermoplastic resin composition 8 having a polymer resin as a main component and a particle size of about 250 μm is
After passing through the fluidized bed 19 fluidized by 9a to adhere the powdery thermoplastic resin between the filaments of the glass fiber 7, it is heated and heated by a pair of rolls 21 heated to about 180 ° C. Press to melt the thermoplastic resin and glass fiber 7
A tape-shaped continuous fiber reinforcing material 6 having a width of about 30 mm and a thickness of 0.5 mm in which a thermoplastic resin was impregnated between the filaments was prepared.

3) Manufacture of composite pipe With the device shown in Fig. 2, the diameter created in 1) is about 1 m.
Eight continuous fiber materials 2 impregnated with polyvinyl chloride resin were introduced between the filaments of m into the resin flow path 13 from the rear of the mold (temperature = about 205 ° C) 12 and chlorine was discharged from the extruder 11. The modified polyvinyl chloride resin composition was extruded to form a thermoplastic resin tube 3 (outer diameter = 40 mm, wall thickness = 2 mm) in which eight continuous fiber materials 2 were evenly embedded in the tube wall.

Then, on the outer periphery of the thermoplastic resin tube 3, created in 2),
A continuous fiber reinforcement 6 impregnated with a vinyl acetate-vinyl chloride copolymer resin is wound between filaments and heated by a heating device 14 of a far infrared heater, and the thermoplastic resin tube 3 and the continuous fiber reinforcement 6 are fused and integrated. To form a reinforcing layer 4 having a thickness of about 1 mm.

Then, the tubular body provided with the reinforcing layer is introduced into the coating die 16, and the polyvinyl chloride resin extruded from the extruder 15 is added to the reinforcing layer 4.
The outer layer 5 with a thickness of about 1 mm is formed by coating the outer periphery of the water tank 1
Cooled at 7.

The above-mentioned series of steps was carried out while taking the composite pipe 1 continuously.

The obtained composite pipe 1 has an outer diameter of 44 mm, and in the longitudinal direction of the pipe,
A continuous glass fiber material 2 in which a polyvinyl chloride resin is impregnated between filaments is provided on the outer periphery of a polyvinyl chloride chloride resin tube 3 embedded in the tube wall, and is a continuous glass fiber-reinforced vinyl acetate-vinyl chloride copolymer. The resin reinforcing layer 4 was fused, and the outer layer 5 made of polyvinyl chloride resin was fused to the outer periphery of the reinforcing layer.

Example 2 1) Preparation of thermoplastic resin tube Using the extruder 11 and the mold 12 shown in FIG. 2, as continuous fiber material 2, ten yarn-shaped aramid fibers (1500 denier) composed of filaments having a diameter of 12 μm were used. Is introduced into the resin path 13 from the rear of the mold 12, the polyphenylene sulfide resin is extruded from the extruder 11 and formed into a tubular shape, and the water tank
While being cooled at 17, it was continuously taken up by a take-up machine 18 to prepare a thermoplastic resin pipe 3 in which ten reinforcing materials 2 were evenly embedded and arranged in the pipe wall.

1) Manufacture of composite pipe Cut the thermoplastic resin pipe 3 created in 1) to a length of 3 m,
Set it on the winding device 23 as shown in FIG.
While rotating the thermoplastic resin tube 3 with a winding device, after winding the roving glass fiber impregnated with the unsaturated polyester resin containing the room temperature curing agent and the curing accelerator around the outer periphery of the thermoplastic resin tube 3, 30 The unsaturated polyester resin was allowed to stand for 5 hours in an atmosphere of ° C to cure the unsaturated polyester resin to form a reinforcing layer 4 having a thickness of about 1 mm, to obtain a composite tube 1.

The obtained composite pipe has an outer diameter of about 42 mm, and the continuous aramid fiber material arranged in the longitudinal direction of the pipe was reinforced with continuous glass fibers on the outer periphery of the polyphenylene sulfide resin pipe embedded in the pipe wall. It is a composite tube provided with a reinforced layer of unsaturated polyester resin.

Comparative Example In the section "2) Production of composite pipe" of Example 2, the thermoplastic resin pipe 3 was made of a polyphenylene sulfide resin which was not one in which the continuous fiber material was embedded in the pipe wall.
A composite tube was manufactured in a similar manner.

The obtained composite pipe is a composite pipe in which a reinforced layer of an unsaturated polyester resin reinforced with continuous glass fibers is provided on the outer periphery of a polyphenylene sulfide resin pipe.

(Evaluation) The composite pipes obtained in Example 1, Example 2 and Comparative Example are each 1 m in length.
Cut into hot water (90 ℃) and cold water (25 ℃) in each composite pipe.
℃) was repeated alternately every 15 minutes to carry out the cold heat repeated test.

Observing the state after 5000 cycles of the above test,
The above was not observed in the composite pipes obtained in Examples 1 and 2, but in the composite pipes obtained in Comparative Examples, peeling occurred at the interface between the thermoplastic resin pipe of the inner layer and the reinforcing layer.

(Effect of the invention) In the composite pipe according to the present invention, since the thermoplastic resin pipe of the inner layer is formed by embedding the continuous fibers arranged in the longitudinal direction of the pipe in the pipe wall, when hot water is flown Even when used at high temperature, the inner layer pipe has a small elongation, is less likely to peel at the interface with the reinforcing layer, and is excellent in watertightness. Further, since a reinforced layer of a resin reinforced with continuous fibers is provided on the outer periphery, it has excellent pressure resistance and impact resistance.

Furthermore, in the present invention, the thermoplastic resin tube of the inner layer,
A crosshead type pipe die is used, and continuous fiber material is introduced into the resin passage from the rear of this die, and the continuous fiber material is embedded in the extruded thermoplastic resin for easy and continuous molding. Since it is possible to remove the mandrel from the mandrel like the FRP pipe obtained by forming the thermosetting resin reinforced layer of the inner layer on the mandrel, it is easy to manufacture the composite pipe. There are advantages.

Further, the reinforcing fiber of the reinforcing layer provided on the outer periphery of the thermoplastic resin tube of the inner layer is a continuous fiber and not a short fiber, so roving-shaped or strand-shaped continuous fiber is used in a thermosetting resin liquid bath or in a thermosetting resin solution. There is also an advantage that the material forming the reinforcing layer can be easily and continuously formed only by passing through the fluidized bed of the curable resin powder or the dispersion liquid to impregnate it and then heating.

[Brief description of drawings]

FIG. 1 is a sectional view of a composite pipe according to the present invention, FIG. 2 is a partial sectional view for explaining a process for manufacturing the composite pipe according to the present invention, and FIGS. 3 and 4 are continuous views, respectively. Explanatory drawing which shows the process of impregnating a fiber material with thermoplastic resin, 5th
The figure is an explanatory view showing the winding step. 1; Composite tube, 2; Continuous fiber material 3; Thermoplastic resin tube, 4; Reinforcement layer 5; Outer layer, 6; Continuous fiber reinforcement material 11, 15; Extruder, 12; Mold 14; Heating device, 17; Cooling Device 18; take-off machine

Front Page Continuation (56) References JP-A-63-251685 (JP, A) JP-A-59-47590 (JP, A) JP-A-63-152786 (JP, A) JP-B-62-773 (JP , B2) JP-B 62-22038 (JP, B2) JP-B 51-22960 (JP, B2)

Claims (3)

[Claims] 1. A continuous fiber reinforced resin reinforced layer is provided on the outer periphery of a thermoplastic resin tube which is an inner layer formed by embedding continuous fiber materials arranged in the longitudinal direction of the tube in a tube wall. A composite pipe characterized by being formed. 2. A reinforced layer of a continuous fiber reinforced thermoplastic resin is provided on the outer periphery of a thermoplastic resin tube which is an inner layer formed by embedding continuous fiber materials arranged in the longitudinal direction of the tube in a tube wall. A composite pipe characterized by being fused together. 3. A continuous fiber material is provided on the outer periphery of an inner layer thermoplastic resin tube formed by burying a continuous fiber material in which a thermoplastic resin is impregnated between filaments arranged in the longitudinal direction of the tube and embedded in the tube wall. A composite pipe comprising a reinforced layer of reinforced resin.