JP3181383B2 - Manufacturing method of fiber reinforced synthetic resin tube - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a fiber-reinforced synthetic resin pipe suitable for use in a drain pipe or the like which is mainly provided with a downward slope.

[0002]

2. Description of the Related Art Conventionally, drain pipes (hereinafter referred to as "inclined pipes") which are piped on high-gradient terrain where flow velocity needs to be adjusted, when the inner surface is a curved surface having a high lubricity, the fluid flowing therethrough is used. Acceleration is applied to the pipe, and the inner surface of the pipe becomes severely worn, shortening the service life.Thus, the wall thickness must be increased, resulting in high cost.Also, even if the wall thickness is increased, If excessive fluid pressure is applied to the connecting pipe and the connecting part separates, or if there is a water collecting basin directly under the drain pipe, a dent is formed at the bottom of the basin due to the water pressure that quickly falls into the basin, The flow after that was not able to proceed smoothly, and in severe cases, the basin itself could be destroyed. And the case of the fiber reinforced synthetic resin pipe was no exception.

By the way, as a method of manufacturing a fiber-reinforced synthetic resin tube, for example, a curable resin-impregnated reinforcing fiber is spirally wound on a core mold which moves in the axial direction while rotating in the circumferential direction.
The so-called filament winding method (hereinafter referred to as "FW method") for curing a resin to produce a fiber-reinforced synthetic resin tube.
Is common.

As a means for solving this problem, there is known a technique in which the inner surface of a fiber-reinforced synthetic resin inclined tube is made rough by making the inner surface uneven, thereby reducing the flow of fluid.

[0005]

However, in order to form irregularities on the inner surface of the tube by the FW method, it is necessary to use a core mold having a corresponding concave and convex strip on the surface thereof. Of course, the special core mold cannot be used for the normal FW method, but when molding a mold with different irregularities,
In each case, it is necessary to prepare a core mold having the corresponding ridges and protrusions, and there has been a problem that the equipment cost increases.

The present invention solves the above-mentioned disadvantages of the prior art, and provides a fiber-reinforced synthetic resin tube used for an inclined tube or the like by using F
In the case of manufacturing using the W method, not only a normal fiber-reinforced synthetic resin pipe having the same core shape and a smooth inner surface, but also a method of manufacturing a fiber-reinforced synthetic resin pipe capable of forming various irregularities on the inner surface. The purpose of this is to provide.

[0007]

SUMMARY OF THE INVENTION According to the present invention, there is provided a " rotation in the circumferential direction.
In the method of manufacturing a fiber reinforced synthetic resin pipe by spirally winding a curable resin-impregnated reinforcing fiber on a core mold moving in the axial direction while moving , in advance, a winding pitch of the reinforcing fiber is set on the core mold. A method of manufacturing a fiber-reinforced synthetic resin pipe, comprising forming a concave-convex strip by winding a spacer having a short width so as to be peelable, and spirally winding a reinforcing fiber thereon. Things.

That is, prior to winding the resin-impregnated reinforcing fibers on a core mold used in a normal FW method, a spacer is spirally wound with a space between the spacers to form a spiral on the core mold. The main point is to form a rough surface on the inner surface of the fiber-reinforced synthetic resin layer formed on it so that the rough surface can be removed. is there.

The method for producing a fiber-reinforced synthetic resin tube of the present invention uses the FW method, and various methods are conventionally known. In other words, cardboard is spiraled into a cantilevered metal tube
Wound adjacent to each other, moved in the axial direction, and
A core mold that moves in the axial direction while rolling is formed.
Core type that moves in the axial direction while rotating in the circumferential direction formed by
A method of spirally winding a curable resin-impregnated reinforcing fiber ,
A curable resin is applied to a cylindrical core formed by spirally winding an endless steel belt around a rotating mandrel.
The impregnated reinforcing fiber is spirally wound and formed, and after curing, an endless steel belt is passed through the axial cavity of the mandrel, and a method of using a Dorstholm machine to return to the winding start position, etc. In the present invention, any of the above methods can be applied.

[0010] In the present invention, in the step before winding the reinforcing fiber on the core mold, a spacer having a width shorter than the winding pitch of the reinforcing fiber is wound on the core mold in advance to form the uneven strip. Need to be formed. By the way, the winding pitch of the reinforcing fibers referred to here is, for example, as shown in FIG.
In the method of winding and forming the core by rotating it in the axial direction (rightward in the drawing) while rotating it in the circumferential direction, the core die a makes one rotation in the circumferential direction and the distance D1 travels in the axial direction. The movement of the core a is set so that the reinforcing fibers b (shown by virtual lines) are spirally wound adjacent to each other, so that the distance is substantially equal to the width of the reinforcing fibers b. Here, when the spacer c is wound, a spacer D2 having a width shorter than D1 is used to form the concave and convex strips d, d.

The spacer used in the production method of the present invention may be a long strip made of paper, synthetic resin, synthetic rubber or a composite thereof, and may be used after the fiber-reinforced synthetic resin layer formed thereon is cured. Preferred are those which are easily peeled from the synthetic resin layer and those which have elasticity so as to easily fit on the surface of the core mold.

[0012]

The method of manufacturing the fiber reinforced synthetic resin pipe of the present invention employs a so-called FW method, in which a spacer is wound before forming the fiber reinforced synthetic resin layer to form a spiral on the surface of the core mold. Since it was made to form a shape of unevenness,
By setting the width and thickness of the spacer as appropriate, it is possible to form an arbitrary uneven strip on the core mold, and since this spacer is peeled off from the tube after molding, one core mold Thus, not only a tube having a normal smooth inner surface but also a tube having various irregularities can be formed.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a view showing an embodiment of the present invention. In the present embodiment, a FW method in which a core mold is moved in the axial direction while rotating in a circumferential direction and wound and formed is adopted.

In FIG. 1, reference numeral 1 denotes a core type, which is a device which moves in the direction of arrow B while rotating in the direction of arrow A. 2
Is a spacer wound first on the core mold 1,
It consisted of a paper strip having a width of 70 mm and a thickness of 1.5 mm, and the distance between the spacers was 10 mm. Therefore, the winding pitch of the concave and convex strips 3, 3,... Formed on the core mold 1 is 80 mm.
Becomes

Reference numeral 4 denotes a releasable film, which is made of a thermoplastic resin film, and is made of a belt-like body wider than the spacer 2. The releasable film 4 is provided with releasability between the core mold 1 and the spacer 2 and the resin tube to be molded, and also to prevent the resin from entering the interface between the core mold 1 and the spacer 2. It is used. If the spacer 2 has high releasability from the fiber-reinforced synthetic resin layer, it is not necessary.

Reference numeral 5 denotes a thermosetting resin-impregnated reinforcing fiber wound on the peelable film 4 at a winding pitch of 80 mm, and after curing, forms a fiber-reinforced synthetic resin inner layer. 6
Is a resin mortar layer forming material wound on the thermosetting resin-impregnated reinforcing fiber 5, and after curing, forms an intermediate layer made of resin mortar.

Reference numeral 7 denotes a thermosetting resin-impregnated reinforcing fiber wound on the resin mortar layer forming material 6, and after curing, forms a fiber-reinforced synthetic resin outer layer. After each molding material is wound in this way, the molding material is passed through a curing furnace (not shown) to cure the resin and complete the molding.

As shown in FIG. 2, the fiber reinforced synthetic resin pipe P1 formed as described above has a fiber reinforced synthetic resin inner layer 51, a resin mortar layer 61, and a fiber reinforced synthetic resin outer layer 7 as shown in FIG.
1 is a composite tube having a three-layer structure.

The fiber reinforced synthetic resin pipe P1 continuously formed from the forming apparatus is cut to a suitable length. After that, the spacer 2, the releasable film 4 and the like adhering to the inner surface of the tube are peeled and removed from the inside of the tube.

The fiber-reinforced synthetic resin pipe P2 thus obtained
As shown in FIG. 4, the concave and convex strips 31, 31,... Corresponding to the concave and convex strips 3, 3,.

[0021]

The method for producing a fiber-reinforced synthetic resin pipe according to the present invention is a production method based on the so-called FW method, in which a spacer is wound on the surface of the core mold by forming a spacer prior to forming the fiber-reinforced synthetic resin layer. Since the helical ridges are formed, by setting the width and thickness of the spacer to appropriate values, any ridges and valleys can be formed on the core mold. Since it is detached from the body, a single core mold can be used to mold not only a tube having a normal smooth inner surface but also a tube having various irregularities. In addition, the existing core mold can be used as it is.

Therefore, the manufacturing equipment cost can be reduced gradually.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view showing an embodiment of the present invention.

FIG. 2 is an enlarged cross-sectional view of a pipe wall of a resin pipe immediately after being manufactured by the above-described manufacturing method.

FIG. 3 is an explanatory diagram showing a dimensional relationship between a spacer and a molding material in the manufacturing method of the present invention.

FIG. 4 is a partially cutaway perspective view of a fiber-reinforced synthetic resin pipe obtained by the manufacturing method shown in FIG.

[Explanation of symbols]

 Reference Signs List 1. a core type 2, c spacer 3, d uneven strip 4 peelable film 5, 7 thermosetting resin impregnated reinforcing fiber 6 resin mortar layer forming material 31 uneven strip 51 fiber reinforced synthetic resin inner layer 61 resin mortar layer 71 fiber reinforced Synthetic resin outer layer P1, P2 Fiber reinforced synthetic resin tube

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI B29K 105: 06

Claims (1)

(57) [Claims] In a method for manufacturing a fiber-reinforced synthetic resin tube, a curable resin-impregnated reinforcing fiber is spirally wound on a core mold that moves in the axial direction while rotating in the circumferential direction. A fiber-reinforced synthetic resin tube characterized in that a spacer having a width shorter than the winding pitch of the reinforcing fibers is releasably wound to form an uneven strip, and the reinforcing fibers are spirally wound therefrom. Manufacturing method.