JPH0460292A - Manufacture of fiber reinforced resin pipe - Google Patents

Abstract

PURPOSE:To improve fiber reinforcing effect and dimensional accuracy of a pipe, in which the fusion of internal layered pipe and fiber reinforcing complex is excellent, by coating the surface of the extension core of a mold to extrude an internal layered pipe made of thermoplastic resin with fluorine contained resin and winding fiber complex on the outer surface of the internal layered pipe. CONSTITUTION:Rolls 5 and 8 comprising sheets 6 and 9, on which polyethylene resin powder fused, wound around glass fibers, for example, are set to winding devices 17 and 18. Polyethylene resin is fed from an extruder 1 to a mold 2, and an internal layer pipe 16a is extruded along the outer peripheral surface of an extension core 3, to which fluorine contained resin process is applied, and fiber complex is wound around the internal layer pipe 16 with the surface heated by heaters 13a and 13b. This is introduced to a cross-head die and is coated and layered by the polyethylene extruded from an extruder 11. In the next step, this is cooled and hardened in a cooling bath 14 and taken up by a take-up machine 15 becoming a three layered structure reinforced resin pipe 16. As a result, a fiber reinforced resin pipe which is accurate in dimensions can be manufactured.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a fiber-reinforced resin pipe that is suitably used under high temperature and pressure conditions.

[Conventional technology]

As a synthetic resin pipe that is lightweight, does not rust, and has pressure and impact resistance, for example, as described in JP-A-63-152786, fibers are used on the outer surface of an inner pipe made of thermoplastic resin. A method of manufacturing a fiber-reinforced resin pipe has been proposed in which a reinforcing layer made of a reinforced fiber-reinforced thermoplastic resin is provided and the outer surface of the reinforcing layer is further coated with a thermoplastic resin layer.

The manufacturing method for this fiber-reinforced resin tube involves heating the inner layer tube, which serves as the core material, to a temperature that melts the surface, and then winding a strand-shaped reinforcing fiber impregnated with thermoplastic resin between the filaments around the outer circumference of the inner layer tube. Then, a reinforcing layer was provided by fusing the two resins together, or by winding reinforcing fibers around the outer surface of the inner pipe and then heating the inner pipe to a temperature that fuses it to the surface. After that, a thermoplastic resin is extruded and coated on the outer periphery of this reinforcing layer.

[Problem that the invention attempts to solve]

However, in the conventional manufacturing method described above, in order to fuse the reinforcing fibers to the outer surface of the inner layer pipe molded from thermoplastic resin,
It is necessary to heat the tube to a temperature that fuses it to the surface of the inner tube. In this case, there is a problem in that the inner layer tube softened by heating is easily deformed by the tension of the reinforcing fibers wound around it, making it difficult to obtain a fiber-reinforced resin tube with high dimensional accuracy.

The present invention solves the above-mentioned problems of the prior art, has good fusion between the thermoplastic resin inner tube and the fiber-reinforced composite, has an excellent fiber reinforcing effect, and does not cause deformation of the inner tube.
The purpose is to provide a fiber reinforced resin pipe with excellent dimensional accuracy.

[Means to solve the problem]

The method for producing a fiber-reinforced resin pipe of the present invention involves extruding a thermoplastic resin to form an inner layer tube, and making the thermoplastic resin held or fused to reinforcing fibers made of a large number of filaments on the outer surface of the inner layer tube. In a method for manufacturing a fiber-reinforced resin pipe by winding or surrounding a fiber composite to fuse the two resins, an extension core is protruded in the extrusion direction of a mold for extruding the inner layer pipe, and the surface of the extension core is is coated with a fluororesin, and the fiber composite is wound or surrounded on the outer surface of the inner tube on the extended core, thereby achieving the above object.

The present invention will be explained in detail below.

In the present invention, thermoplastic resins used as raw materials for the inner layer of the fiber-reinforced resin tube include, for example, polyvinyl chloride, chlorinated polyvinyl chloride, polyethylene, polypropylene, polystyrene, polyamide, polycarbonate, polyphenylene sulfide. , polysulfone, polyetherketone, etc., and there is no particular limitation as long as it can be extruded into a tubular shape, and a thermoplastic resin suitable for the intended use of the resin pipe can be used as appropriate. These thermoplastic resins may be used alone or in combination. In addition, these thermoplastic resins contain heat stabilizers, plasticizers, lubricants,
Additives such as antioxidants, ultraviolet absorbers, pigments, inorganic fillers, reinforcing fibers, fillers, processing aids, modifiers, etc. may be added depending on the purpose of use. Moreover, the inner layer tube may be a laminate formed by laminating a plurality of layers of thermoplastic resins selected from the above. The fiber composite wound around or surrounding the outer surface of the inner tube may be one in which reinforcing fibers consisting of a large number of continuous filaments are impregnated with a thermoplastic resin, or the thermoplastic resin may be melted and made into a sheet. is used. Examples of the reinforcing fibers used include glass fibers, carbon fibers, metal fibers, and various synthetic fibers such as aramid fibers and vinylon fibers.
Rovings made up of several thousand strands or string-like or tape-like ones made from yarn are generally used. If the thickness of the fiber composite is too thin, it lacks strength, and if it exceeds 2 m, it becomes difficult to wind. .

The thermoplastic resin that is retained or fused to the reinforcing fibers by impregnation or the like is not particularly limited as long as it can be fused to the inner layer tube, but it must be highly compatible with the inner layer tube and equivalent to the resin of the inner layer tube. A thermoplastic resin that melts or softens at a temperature higher than that or lower is preferable. That is, from among the thermoplastic resins used as raw materials for the inner layer tube, it is preferable to use a resin whose melting point or thermal deformation temperature is lower than that of the inner layer tube.

The fiber composite is produced by (1) passing strand-shaped reinforcing fibers such as rovings or yarns made of filaments through a fluidized bed of powdered thermoplastic resin to impregnate the spaces between the filaments with the thermoplastic resin; (3) pass through a bath of molten thermoplastic resin to adhere the thermoplastic resin between the fibers, and then dry; The fiber composite may be formed as is, or it may be integrated using a heated pressure roll and formed into a string or tape shape.

In the case of methods (1) and (2), the thermoplastic resin impregnated between the filaments can also be used in powder form. The ratio of the reinforcing fibers and the thermoplastic resin in the fiber composite is selected as appropriate within the range of 5 to 80% by volume of the reinforcing fibers.

It is difficult to obtain a reinforcing effect by the reinforcing fibers, and if the content exceeds 80% by volume, it becomes impossible to fuse the inner layer resin pipe with the interface, making it difficult to obtain a sufficiently fused fiber-reinforced pipe with high strength. The term fusion-bondable as used herein refers to a state in which both resins are heated until they become molten and pressed together, and the fused interface is not easily cut after cooling.

FIG. 1 is a front view illustrating an embodiment of the present invention.

The manufacturing apparatus used in one embodiment of the present invention includes an extruder 1 for extruding a thermoplastic resin, a mold 2 attached to the tip of the extruder 1 for extruding a hollow thermoplastic resin tube 16a, and a mold 2 for extruding a hollow thermoplastic resin tube 16a. a winding device 17.18 for winding the fiber composite 6.9 around the outer surface of the inner layer tube 16a extruded from the inner layer tube 16a;
An extruder 11 for extruding resin to form a resin layer is attached to the outer surface of the cylindrical body 16b in which the fiber composite 6.9 is wound around the outer surface of the inner tube 16a, and an extruder 11 is attached to the tip of the extruder If. A crosshead die 12, a cooling device 14 such as a water tank, and a take-up machine 15 are provided. An extension core 3 protrudes in the extrusion direction of the molding die 2, and the surface of the extension core 3 is coated with a fluororesin. Here, examples of the fluororesin to be coated include polytetrafluoroethylene, polytetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, and tetrafluoroethylene-ethylene copolymer. , polychlorotrifluoroethylene, etc., and those that are heat resistant, firmly adhere to the core metal, and have a low surface friction coefficient are particularly suitable for solving the above problems.

Further, the protrusion length of the extension core 3 is not particularly limited, but it may be extended to a position where the fiber composite 6.9 is wound around the outer surface of the inner layer tube 16a.

The winding devices 17 and 18 have spindles 4 and 7 that support rolls 5 and 8 around which the fiber composites 6 and 9 are wound, and rotate around the inner layer tube 16a to rotate each roll. The fiber composites 5.8 to 6.9 are wound in sequence.

As shown in FIG.
A pair of spindles 4.7 of the winding devices 17.18 are arranged on both sides of the winding device 17.a so that the fiber composite 6.9 unwound from the rolls 5°8 is inclined with respect to the axial direction of the inner layer tube 16a. are arranged at a suitable angle, and both rolls 5.8 are arranged to rotate in opposite directions around the inner tube 16a. In this way, as shown in Figure 2,
The fiber composite 6.9 is wound like a braid around the outer surface of the inner layer pipe 16a, resulting in a fiber reinforced resin pipe 1 with excellent internal pressure resistance.
As the winding devices 17 and 18 for obtaining 6, a commonly used total composition forming machine is used. Further, the heating devices 3a, 3b may be provided with only one winding device or three or more winding devices, and are arranged in the portion where the fiber composite 6.9 is wound.

The shape of the introduction port of the rad die 12 to the cross is the cylindrical body 16b.
The resin extruded from the extruder 11 is a thermoplastic resin, similar to the resin extruded from the extruder jli1.

The thermoplastic resin extruded from the extrusion III passes through the mold 2 to form the inner layer tube 16a. Note that the shape of the inner layer tube 16a may be cylindrical or rectangular, etc. depending on the shape of the mold 2.

Next, a fiber composite 6°9 impregnated with a thermoplastic resin is wound around the outer surface of the inner pipe 16a from a winding device 17°18, and the resin is melted using heating devices 13a and 13b to separate the inner pipe 16a and the fibers. Integrate with complex 6.9.

Next, the fiber composite 6. is wound around the outer surface of the inner layer tube 16a.
9 is heated on the outer surface of the inner pipe 16a by the heating devices 13a and 13b, softened along the surface of the inner pipe 6a, and fused and integrated with the inner pipe 16a. Here, in order to increase the fusion strength of the fiber composites 6.9, the inner layer tube 16a is pressed while pressing the fiber composites 6, 9 with a roll-shaped pressing.
It may be wound and fused.

Next, the cylindrical body 16b around which the fiber composites 6 and 9 are wound in this manner is guided to the crosshead tie 12, and the outer surface of the cylindrical body 16b is coated with synthetic resin to form an outer layer 16C. be done. Here, it is highly preferable that the fiber composites 6 and 9 be coated with a thermoplastic resin of the same quality as the thermoplastic resin impregnated, and the outer layer 16C will be firmly adhered to the outer surface of the cylindrical body 16b. Thereafter, it is supplied to a cooling device 14 to be cooled, and then taken off by a take-off machine 15 to obtain a fiber-reinforced resin pipe 16.

In this way, the fiber composite 6,
Fiber-reinforced resin pipe 1 with high pressure resistance and integrated coating 9
6 is obtained.

FIG. 3 is a front view illustrating another embodiment of the present invention.

The sheet-like fiber composite 24 is continuously fed from behind the inner mold 22 through an annular gap formed by the outer periphery of the inner mold 22 and the shaping rolls 25 and 26, so that the continuous fibers are Form a cylindrical body 30a arranged in the direction (fourth
(see figure).

At this time, the sheet-like fiber composite 24 is heated by the heating means 37.
By heating the cylindrical body 30a, the forming roll 2526 can be heated to facilitate the formation of the cylindrical body 30a.
It may be heated to a temperature higher than the softening temperature of No. 4.

Subsequently, the cylindrical body 30a is introduced into the annular space formed by the inner core 221 and the outer mold 222.

Here, the thermoplastic resin extruded from the extruder 21 is formed into a cylindrical shape by an inner core 221, and the inner layer thermoplastic resin is extruded and laminated inside the cylindrical body 30a within the inner core 221 to form a two-layer tube 30b. do.

Next, the winding device 28 is rotated to wind the fiber composite 29 around the two-layer tube 30b, and the fiber composite 29 is heated by the surface heating means 38 to fuse the glabella, and the continuous fibers are arranged in the circumferential direction of the tube. A three-layer pipe 30c provided with a reinforced layer is formed.

At this time, on the outside of the extension core 23 that protrudes in the extrusion direction of the inner core 221 and whose surface is coated with fluororesin,
A method of winding the fiber composite 29 on the outer surface of the 3N pipe 30C is adopted to prevent the two-layer pipe 30b from being deformed when the fiber composite 29 is wound.

Subsequently, a thermoplastic resin is introduced from the extruder 31 through the coating mold 32 to form a coating layer around the outer periphery of the three-layer pipe 30c, and then
A fiber-reinforced resin pipe 30 is produced by cooling and sizing using a cooling device 34 such as a water tank, and then taken by a taking machine 35 .

[Effect]

In the method for manufacturing a fiber composite tube of the present invention, an extension core is protruded in the extrusion direction of a mold for extruding an inner layer tube, the surface of the extension core is coated with a fluororesin, and a fiber composite tube is coated on the outer surface of the inner layer tube on this extension core. Because it wraps or surrounds the body, it prevents the extruded inner layer from coming into close contact with the core, and effectively prevents the inner tube from deforming when the reinforcing fiber layer is wound around the outer surface of the inner tube.
In addition, the frictional resistance between the molded tube and the core is significantly reduced,
The reinforced resin tube can be moved without deforming it by pulling the tube in the distal direction with a pulling device.

〔Example〕

1 ship 1 Using the device shown in Figure 1, sheets 6.9 made by adhering polyethylene resin powder to glass fibers and fusing them were wound around the spindles 4.7 of the winding devices 17 and 18, respectively. Rolls 5 and 8 were set. The thickness of this sheet 6.9 is 0.
It had three views and a width of 30 temples.

Polyethylene resin is sent from extruder 1 to mold 2 whose temperature is controlled at 180°C, and extension core 3 is processed with fluororesin.
(outer diameter 90 mm), push out the inner layer tube 16a with an outer diameter of 100 mm, and place the heater 1 on the surface of the inner layer tube 16a.
3a and 13b while heating to about 180°C. This was introduced into a cloth whose temperature was controlled at 180°C through a Rad die, and then covered with a polyethylene resin extruded from an extruder 11 and laminated thereon. Next, it is introduced into a cooling tank 14 to be cooled and solidified, and taken out by a take-up machine 15 to form a reinforced resin pipe 16 with a three-layer structure.
I got it. The outer diameter of the obtained reinforced resin tube 16 was 108 cm. At this time, the inner NN does not come into close contact with the core, and the fiber-reinforced resin tube does not deform when the reinforced resin layer is wound or taken off by a take-off machine, and the fiber-reinforced resin tube has good dimensional accuracy. could be manufactured.

〔effect〕

In the method for manufacturing a fiber-reinforced resin pipe of the present invention, an extension core is protruded in the extrusion direction of a mold for extruding an inner layer pipe, the surface of the extension core is coated with a fluororesin, and the outer surface of the inner layer pipe is coated on the extension core. Since the fiber composite is wound or surrounded by the core, the inner resin layer does not come into close contact with the core.
Further, the fiber reinforced resin tube is not deformed when the reinforced resin layer is wound and taken off by a take-off machine, and a fiber reinforced resin tube with good dimensional accuracy can be manufactured.

[Brief explanation of the drawing]

FIG. 1 is a front view illustrating one embodiment of the present invention, FIG. 2 is a partially cutaway front view showing a composite pipe manufactured according to the embodiment of FIG. 1, and FIG. 3 is another embodiment of the present invention. FIG. 4 is a front view for explaining an example, and FIG. 4 is a plan view showing a state in which a reinforcing fiber layer is surrounded between an inner core and a forming roll to form a fiber composite in the embodiment of FIG. 3. 1.21... Extruder, 2,22... Mold, 3.23
...Extended core, 6.9.24.29・Reinforced composite, 1
1.31...Extruder, 12.32...Cross rad die, 14.34...Cooling device, 15.35...Take-off machine, 16.30...Fiber reinforced resin pipe.

Claims (1)

[Claims] (1) A thermoplastic resin is extruded to form an inner layer tube, and a fiber composite in which the thermoplastic resin is held or fused to reinforcing fibers made of a large number of filaments is wound or surrounded on the outer surface of the inner layer tube. In the method for manufacturing a fiber-reinforced resin pipe in which both resins are fused together, an extension core is protruded in the extrusion direction of a mold for extruding the inner layer pipe, the surface of the extension core is coated with a fluororesin, and this A method for manufacturing a fiber-reinforced resin pipe, comprising winding or surrounding the fiber composite on the outer surface of the inner layer pipe on an extended core.