JPS60203428A - Manufacture of frp pipe - Google Patents

Abstract

PURPOSE:To manufacture an FRP pipe whose thickness is thin, strength and rigidity are high, by making reinforced fibers of the innermost layer and the outermost layer are made to continue unitarily. CONSTITUTION:A molding material is obtained by laminating cloth prepreg 2, 2a having an identical width with a circumference of a pipe on the top and bottom of cloth prepreg 1 whose thickness is about two times of the circumference of the pipe cut off so that fiber is arranged at an angle of 45 deg. with the direction of a pipe axis. Then the molding material is laminated by winding the same around a core metal 3 so that the innermost layer and the outermost layer are continued unitarily and cured by heating and pressing the same. With this construction, an anisotropic and thin pipe whose torsional rigidity and strength are high and reinforcing fibers in a bias and parallel directions with the pipe axis are laminated each other can be manufactured easily.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a method for manufacturing a motherboard made of FRP.

[Prior art]

FRP t4? In pipes in which tensile, compressive, and torsional forces act on the rib, the S fibers can be moved in a direction parallel to the *iso axis (hereinafter referred to as the O0 direction) and in a bias direction (hereinafter referred to as diagonally intersecting the *iso axis). (referred to as 45° direction)
It is necessary to strengthen the fibers.

In such a pipe, the fibers are arranged in the KO'' direction in either or both of the innermost layer and the outermost layer, and the pipe can withstand extreme temperature differences from around -150°C to around +100°C, such as under space environment conditions. If it is large, the resin layer may crack parallel to the fibers in the zero direction fiber material due to thermal stress due to the difference in thermal expansion coefficient between the Oo direction reinforced fiber material and the 45° direction reinforced fiber material. One way to prevent this phenomenon is to arrange reinforcing fibers in the 45° direction on the inner and outer layers of the vibrator.

In this way, the inner and outer layers of the pipe are reinforced with axial fibers (
a) The innermost reinforcing fiber layer is provided in the 45° direction using the filament winding method, and then the fibers are pulled in one direction.
Material that has been impregnated with resin and pre-cured in advance (
1) Prepreg (hereinafter referred to as prepreg) is provided as a θ° direction reinforcing fiber layer, and finally, a 45° direction is provided and hardened using the filament winding method.

(b) As the 45° reinforcing fiber material for the outermost layer, a cross prepreg material made by impregnating resin into a cross woven with fibers perpendicular to each other is cut diagonally at a 45° angle, and the fibers are arranged in a 45° direction with respect to the axis of the core metal. After wrapping the material in the same manner as in (a), a 00 direction reinforcing fiber layer of UD prepreg is provided as in (a), and finally, the above cross prepreg is wound again as a 45° direction reinforcing fiber material and hardened.

It was manufactured using manufacturing methods such as

By the way, when manufacturing a pipe made of carbon fiber-reinforced plastic using the above method (a), for example, the number of fibers to be implanted is the same as that of a cloth material woven from carbon fibers with a thickness of about 0.05 to 0.1. Even if the filament winding method is set to helical winding in the i545a direction, it is difficult to wind the fibers uniformly with the exact same precision as cloth material due to the precision of the winding machine, and it is difficult to wind the fibers uniformly with the same precision as cloth material. It was difficult to achieve the thickness reduction of 0.05 to 0.1 M unless the bundle was flattened.

Moreover, the innermost layer has a 45° direction winding, and the middle layer has a 0
Since the molding process is divided into three steps: winding in the 45° direction layer and winding the outermost layer in the 45° direction, the manufacturing process has the drawback of requiring a lot of time.

In addition, according to method (b), since a cloth prepreg is used as the 45° direction reinforcing fiber material, the cloth is impregnated with resin in advance and passed between two rolls in the process of semi-curing. Although it is possible to change the shape of the fibers into a flat shape and create a thin 45° reinforcing fiber layer with a high fiber content, it is not possible to make the 45° oriented fibers continue to both ends of the pipe as in the filament winding method in (a). Impossible, pipe thread rigidity 2
There was a drawback that the strength was lower than that of pipes made using the filament winding method.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the conventional products as described above.
By laminating UD prepregs with fibers oriented in the ``direction'' and wrapping them around a pipe that serves as a core metal, the innermost layer of reinforcing fiber material in the 45° direction continues to the outermost layer, resulting in a thin wall with high strength and high strength. The purpose is to provide a method for manufacturing a rigid FRP pipe.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

Figures 2 and 3 show the molding material of the pipe used in this invention. First, Figure 2 shows a cloth prepreg (with fibers arranged at 45 degrees to the pipe axis) having a width twice the circumference of the pipe. This is a cross prep for reinforcing fibers in the 45° direction, which has a width twice the width of the UD prepreg, which is the same width as the pipe circumference.

By using the molding materials shown in Figures 2 and 3 above and attaching them to the core metal 3, which will become the pipe material, as shown in Figures 4-5, the laminated materials will become as shown in Figures 6-7, respectively. .

By curing the pipe laminated in this manner by applying heat and pressure, a thin-walled pipe in which the fibers of the 45° fiber-reinforced cross prepreg l in the innermost layer continue integrally to the outermost layer can be manufactured.

In the embodiment, the case where the pipe 3 has a circular cross section has been described, but FRP pipes with various cross-sectional shapes can be manufactured by using triangular, quadrangular, or other shapes. In addition, although we have explained the case where one layer of cross prepreg is placed on the innermost and outermost I#, if the width of the cross prepreg is made twice or three times the pipe circumference, the outermost layer can be made into two or three layers. is also possible.

〔Effect of the invention〕

As described above, according to the present invention, reinforcing fibers are arranged in the innermost 1 m and outermost layers in the bias direction with respect to the pipe axis direction,
FRP with reinforcing fibers arranged parallel to the pipe axis in the middle layer
In manufactured pipes, the innermost layer and outermost layer are integrated and continuous, which improves the torsional rigidity and strength of the pipe, and also allows reinforcing fibers to be alternately laminated in the bias direction and parallel direction to the pipe hem. Thin-walled pipes with a certain degree of anisotropy can be easily produced. In addition, since the parallel reinforcing fiber layer is wrapped in a sandwich-like manner from both the inner layer and the outer layer with the cross material in the bias direction, the resin layer in the parallel fiber layer will not resist thermal stress even when exposed to low temperatures of around -150°C. It has the advantage of not causing any cracks.

[Brief explanation of the drawing]

FIG. 1 is a broken perspective view of an FRP pipe according to the present invention.
Figures 2 and 3 are perspective views of reinforcing fibers preformed in a direction parallel to the bias direction to form a pipe, and Figures 4 and 5 are of a state in which they are wound around a core metal. The perspective view, FIGS. 6 and 7 are enlarged cross-sectional views of the finished pipe product. 1... Cross prepreg in bias direction, 2, 2a.
... UD prepreg in parallel direction, 3... Core metal. In addition, in the figure, the same-shrine/number indicates the same- or Buddhist monk part. Figure 6 Figure 7

Claims (1)

[Claims] FRP in which reinforcing fibers are arranged in the bias direction with respect to the pipe axis direction in the innermost layer and outermost layer in the cross-sectional configuration of the FRP arm eve, and reinforcing fibers are arranged in the middle layer parallel to the pipe axis.
Made by A? A method for manufacturing an FRP pipe, characterized in that the innermost layer and the outermost layer are integrally continuous when obtaining the Iso.