JPS60220715A - Continuous forming process of carbon fiber reinforced plastic cylinder - Google Patents

Abstract

PURPOSE:To draw form the CFRP having no breakages or orientation disorders of fibers, high strength and a thin wall by dividing a pultrusion hot die into three parts, i.e. a resin drawing zone, a gelling zone and a curing zone, and regulating the temperature of each part independently. CONSTITUTION:A carbon fiber prepreg 7 wound on a mandrel 8 is passed through the hot die 10 divided into three parts, and is drawn in (C) direction at take up mechanism 9. Thus, a cylindrical CFRP may be formed. The temperature of the resin drawing zone 11 with 4-6 deg. drawing angle (a) is slightly low, and the temperature of gellation zone 12 is sufficient for gellation of the resin for impregnation, and then the curing zone 13 has slightly large inner diameter and its temperature is kept by controlling at the sufficient temperature for curing the resin. The drawing angle (a) is caused to be a suitable angle, and in the front half part of the gelling zone 12 the resin for impregnation gels perfectly, and then in the curing zone 13 the resin is cured at uncontact condition, whereby CFRP having no defects or orientation disorders of the fibers, high strength and a thin wall may be manufactured.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to carbon fiber reinforced plastic (hereinafter referred to as 0FRP).
Regarding continuous cylindrical forming method.

In particular, the present invention relates to a method that can be applied to continuous molding of thin-walled 0FRP cylinders that are lightweight, long, and have high mechanical strength, such as those used as members for large space structures.

[Prior art]

A pultrusion method is well known as a continuous molding method for a long molded product having a constant cross-sectional shape, such as a cylinder made of fiber-reinforced plastic (hereinafter referred to as FRP) impregnated with a thermosetting resin to form a matrix.

BACKGROUND ART Thick-walled insulating pipes, corrosion-resistant pipes, and the like have been manufactured using glass fiber as a reinforcing material.

FIG. 1 is a sectional view illustrating a conventional pultrusion method.

In the figure, (1) is a fiber aggregate impregnated with a thermosetting resin, (2) is a core bar, and (3) is a take-off mechanism.

In this example, the roller, (4) is a hot mold, or hot die, (5) is a hot die (41 inlet constriction part, (6)
is the flat part.

Next, the molding method will be explained. Wrap the fiber aggregate (11) impregnated with a thermosetting resin around the core bar (2), and move it from the trap in the direction of arrow B by rotating the take-up mechanism (3) in the direction of arrow B. Excess resin is removed from the fiber aggregate by the aperture MX151 at the entrance of the hot die (4), the outer shape of the entire co-pressure is adjusted, and the flat part (6) is cured to obtain a cylindrical molded product.

However, such a molding method is used, for example, as a member for a large space structure.

Using carbon fiber as a reinforcing fiber and taking advantage of its superior specific strength and specific modulus cannot be adequately applied to the molding of lightweight, thin-walled 0FRP long cylinders. Namely.

Such molded products are required to be as light as possible to meet the required strength, and to achieve this, it is necessary to reduce the weight by 30M% through thinner walls and molding precision.
It is necessary to improve the strength retention rate of the molded product against the theoretical value due to the composite agent, but conventional molding methods can only achieve this by 30M%.
No consideration has been given to

Conventional pultrusion molding methods are mainly for thick-walled products, and a large amount of excess thermosetting resin is removed.2For example,
The drawing angle of the drawing part (5) is increased or multistage drawing is performed, but this makes the carbon fiber, which is inherently brittle, more likely to break.

In addition, in order to suppress the reverse tension in the drawing process (5), the drawing speed and temperature are set so that the thermosetting resin gels in the latter half of the hot die process (4). As the distance becomes longer, the orientation of the fibers is more likely to be disturbed, both of which cause a decrease in 30M%.

[Summary of the invention]

This invention was made in order to eliminate the above-mentioned drawbacks of the conventional method, and consists of a hot die consisting of three zones: a resin squeezing zone, a resin gelling zone, and a resin hardening zone. By adjusting the temperature individually and completing gelation in the first half of the resin gelation zone, it is possible to continuously obtain 0FRP cylinders with less reduction in ROM% due to bending and disordered orientation of carbon fibers. It is an object.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Second
The figure is a sectional view illustrating a method according to an embodiment of the present invention.
FIG. 3 is an enlarged sectional view of a part of FIG. 2. In the figure, (7) is a carbon fiber prepreg impregnated with a thermosetting resin. Generally, the fibers are used while being impregnated by passing them through a thermosetting resin bath (not shown), or the fibers are pre-impregnated with a thermosetting resin. In some cases, a sheet or tape-like material (prepreg) impregnated with resin is used.

In the case of carbon fibers, it is preferable to use the latter in order to minimize breakage. (8) is the core bar, (9) is the take-off mechanism, QO is the hot die, and I is the resin drawing zone.

02 is the resin gelling zone, J is the resin curing zone, +
141 is a flat cap of the resin squeezing zone, and 19 is a temperature control mechanism for heat insulation.

Next, the formation method will be explained. A tape or sheet of carbon fiber prepreg impregnated with thermosetting resin is attached to a core bar (8
), grab it with the take-up mechanism (9) and follow the arrow 0.
By moving in the direction of , continuously pull through the hot die a value. Hot die Q [I is composed of three cylindrical zones: a resin squeezing zone aυ, a resin gelling zone (LZ, and 0 rows of resin curing zones), and each zone aυ, (
12 and +13 are individually temperature controlled. Moreover, each zone aυ, (12, Q3 has a mating structure that can be split into two, for example, in a cross-sectional direction parallel to the axis of the zero cylinder, in order to facilitate later disassembly and cleaning.

The carbon fiber prepreg, that is, the fiber aggregate (7) wound around the core metal (8) is once returned to a fluid state by a predetermined heating when passing through the resin squeezing zone a9, and the excess resin is removed by the squeezing action. The overall outer diameter is adjusted in the flat portion I, and the fibers are further aligned and moved to the primary resin gelling zone f13.

The squeezing angle of the resin curing zone c111 is made small to prevent the carbon fiber from breaking, and the angle is 4.
Preferably, the angle is within the range of 6° to 6°. This range was set based on the results of various studies.

This is because when the angle is 6 degrees or more, there is a decrease of 80 M%, and when it is 4 degrees or less, the reverse tension increases significantly due to a decrease in the squeezing effect. In addition, the resin squeezing zone (Il+) is set at a relatively low temperature (for example, 90
±10°C (in this example, 90°), whereas in the primary resin gelation zone 02, the temperature is adjusted to a high temperature (for example, 140°) to complete the gelation in the short first half.
C±20°C (1d140°C in this example), and the connecting portions of both zones aD and α2 are in close contact to prevent the carbon fibers from breaking. Therefore, the temperature difference at this connection is approximately 50°C to 100°C.
Since it is not enough to control the temperature of the entire temperature zone at °C, a temperature control mechanism (c), such as a heat or refrigerant circulation path, is required for the flat Tsuzumi 4 of the resin-wrapped zone. It has been incorporated. , (arrows indicate the direction of flow of heat and refrigerant.) Therefore, the restriction zone +
Gelation within Ill is difficult to occur, and even if gelation occurs, it will be confined to the flat portion a4 and will not lead to an increase in reverse tension.

Fiber aggregate (7) wrapped around the core bar (8) that has moved from the resin squeezing zone +111 to the resin gelling zone a3
As described above, the thermosetting resin of
2 is set at a high temperature, gelation occurs in M'c), and a certain gelation state is reached during a short period of time, that is, a relatively short moving distance in the first half, so that the subsequent fiber orientation is disturbed. hard. Therefore, if gelation is carried out in the resin gelling zone (I2) to the extent that the shape of the molded product is deformed, all that is left is to complete the curing with heat, so the diameter of the resin curing zone α is The diameter of the molded product (7), that is, the resin gelation zone α2 exists.

Thus, according to the embodiment described above, the resin squeezing zone a
By reducing the drawing angle of υ to 4° to 6° and connecting the resin drawing zone aυ and the resin gelling zone az without creating a gap between them, bending of the carbon fibers can be suppressed as much as possible. By performing gelation in the resin gelation zone α2 over a short moving distance in the first half, disordered orientation of the fibers can be eliminated.

This is the resin squeezing zone t111 and the resin gelling zone α
In addition to the temperature control mechanism (not shown) for the entire zones u and Q2, an adiabatic temperature control mechanism is incorporated between the zones αB and α2 so that the temperature of each zone αB and α2 can be adjusted completely independently. As a result, there is no increase in reverse tension due to gelation in the resin squeezing zone O1, and 0FRP has less ROM% decrease due to fiber bending and orientation disorder.
Thin cylinders can be obtained continuously.

In addition, in the above embodiment, the collection machine frame (9) shown in FIG. 2 has been described, but the present invention is not limited to this.

For example, other rollers such as the roller (3) shown in FIG. 1 may be used.

Further, in the above embodiment, a case has been described in which the heat-insulating temperature adjustment mechanism α9 is provided in the resin squeezing zone αB, but it may be provided in the resin gelling zone α2. However, in this case, the state of connection of both zones αn and a"a is preferably such that the reverse pressure resin squeeze zone fiυ is depressed and the resin gelation zone a2 is protruded, which is different from that shown in FIG. 3.

In some cases, such as rice fields made of thermosetting resin, the same effects as in the above embodiment can be achieved even without the heat-insulating temperature control mechanism α9.

In addition, in the above embodiment, in order to suppress the reverse tension due to contact resistance, the diameter of the resin hardening zone α9 was changed to the diameter of the resin gelling zone α9.
We have explained the case where the diameter is slightly larger than that of 2, but even if it is not necessarily thicker, a considerable improvement of 80M% can be expected.

〔Effect of the invention〕

As described above, according to the present invention, the hot die is composed of three zones: a resin drawing zone, a resin gelling zone, and a resin curing zone, and each of these zones is individually temperature-controlled, and the resin gelling zone is Since gelation is completed in the first half of the gelation zone, it is possible to continuously obtain 0FRP cylinders with less ROM deterioration due to bending or disordered orientation of carbon fibers.

[Brief explanation of the drawing]

FIG. 1 is a sectional view illustrating a conventional pultrusion method. Figure 2 illustrates a molding method according to an embodiment of the present invention.
3 is an enlarged sectional view of a part of FIG. 2. In the figure, (1) is a fiber aggregate impregnated with a thermosetting resin, +21. +81 is the core metal, +31. (91 is the pulling mechanism, +41°α [is the hot die, (5) is the drawing part, (6) is the flat part, (7) is the carbon fiber prepreg,
αB is the resin squeezing zone, (12 is the resin gelation zone, α
9 is a resin curing zone. The same reference numerals in the five figures indicate the same or corresponding parts. Applicant: Ita Hirobe Yoda, Director of the Agency of Industrial Science and Technology 1. Kyohaku 2. Former No. 3 Written amendment to the prison procedure (spontaneous) Date of issue: 1985, month λλ, Mr. Commissioner of the Japan Patent Office 1. Indication of the case: % Application No. 59-65158 2. Title of the invention Continuous forming method of carbon fiber reinforced plastic circles 4, Address of person making the correction Name Agency of Industrial Science and Technology Next Generation Industrial Technology Planning Office Shi (50)
1) 1511 extensions 4601 to 46054 Target of amendment Detailed explanation of the invention in Specification A 5, contents of amendment (υ "(7) in page 5, lines 8 to 9 of the specification is a thermosetting resin '' should be corrected to ``(7) is a thermosetting resin (epoxy resin in this example).'' (2) Same, page 9, line 19 to page 10, line 4 ``is desirable.'' (4) Same, 1st
Correct "ROM decrease" on page 0, line 20 to "ROM% decrease."that's all

Claims (1)

[Claims] (11) In a device in which a carbon fiber prepreg impregnated with a thermosetting resin is wound around a core metal and continuously drawn out through a hot die for continuous molding, the hot die is connected to a resin drawing zone, a resin gelling zone, etc. The resin curing zone is composed of three zones: a resin curing zone, and a resin curing zone. The temperature of each of these zones is adjusted individually, and gelation is completed in the first half of the resin gelation zone. Continuous molding method for carbon fiber and reinforced plastic cylinders. (2) The squeezing angle of the fallen fat squeezing zone is within the range of 4° to 6°, and the temperature for insulation is maintained between the resin squeezing zone and the resin gelling zone. A method for continuous molding of a carbon fiber reinforced plastic cylinder according to claim 1, wherein the 31 valley zone has a mating structure that can be separated along the axis of the core metal. A method for continuously forming a carbon fiber reinforced plastic cylinder according to claim w1 or claim 2.