JPH0481498B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an uncured FRP tube that can be used as an inner lining material for a pipe body such as an existing pipe, and a method for manufacturing the same.

[Conventional technology]

Conventionally, as a means of constructing an inner lining on a large-diameter pipe, a method was considered in which polyester resin and glass fiber were alternately laminated and defoamed, and then cured to form an FRP coating layer. Not only was the work time-consuming, but there was also concern that large amounts of styrene, the solvent for FRP, would be generated, worsening the working environment.

Therefore, the applicant first inserts an uncured FRP tube of the ultraviolet ray curing type or thermosetting type into the tube, inflates it using appropriate means such as air supply, and from that state irradiates the uncured FRP tube with ultraviolet rays. Alternatively, we proposed a tube inner lining method based on curing by heating. The uncured FRP tube used in this method is obtained by folding both ends of an uncured FRP sheet in the width direction into a tube shape, overlapping each other, and joining the overlapping portions with adhesive tape or the like.

[Problem that the invention seeks to solve]

However, due to its manufacturing method, the above-mentioned unhardened FRP tube has a joint that extends in the axial direction, so when it is inflated by air supply, a gap is created in the joint, which tends to cause air leakage. It has been pointed out that air leakage causes problems such as not being able to obtain a satisfactory inflated state and causing wrinkles.

Furthermore, since the above-mentioned uncured FRP tube itself has adhesive properties, the work of folding it back into a tube shape is troublesome. Therefore, it is possible to manufacture uncured
Another problem was that the length of the FRP tube was severely limited, and the requirements for long tubes to be internally lined could not be met in some cases.

The present invention solves these problems and aims to provide an unhardened FRP tube that has substantially no joints extending in the axial direction.

[Means for solving problems]

In order to achieve the above object, the uncured
An FRP tube is an uncured FRP tube in which multiple layers of uncured FRP tape are spirally wound, and the upper and lower uncured FRP tape layers are integrated by their adhesive properties. The end faces of uncured FRP tapes of the same layer are brought together and joined, and the joint line is the upper and lower uncured FRP tapes.
The FRP tape layers are misaligned in the axial direction, and the innermost layer is uncured FRP.
The gist is that a protective film is held on the inner surface of the tape layer and the outer surface of the outermost uncured FRP tape layer.

[Effect]

The unhardened FRP tube with the above configuration is
The joint edge of the FRP tape extends spirally, and the joint edge is joined by the uncured FRP tape layer of the adjacent layer, and the uncured FRP tape layers of the adjacent layer are also integrated by their adhesiveness. Since it is attached with adhesive, there are no joints anywhere in the axial direction or circumferential direction. Therefore, even when used as the inner lining material for the above-mentioned tube, there is little risk of air leakage occurring during air supply, and a satisfactory inflated state can be obtained. In addition, the uncured innermost layer
The protective film held on the inner surface of the FRP tape layer prevents the inner surfaces from adhering to each other, while the protective film held on the outer surface of the outermost uncured FRP tape layer facilitates handling of the uncured FRP tube.

〔Example〕

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

FIG. 1 illustrates an uncured FRP tube of the present invention. The uncured FRP tube in the same figure consists of three spirally wound uncured FRP tape layers 1,
2, 3, a protective film 4 held on the inner surface of the innermost uncured FRP tape layer 1, and a protective film 5 held on the outer surface of the outermost uncured FRP tape layer 3. And uncured innermost layer
The joint edge 1a where the end surfaces of the uncured FRP tapes forming the FRP tape layer 1 touch each other and the joint edge 2a of the uncured FRP tape forming the intermediate layer uncured FRP tape layer 2 are in the axial direction. The position is shifted to A. That is, in the illustrated example, the joint edge 2a of the uncured FRP tape is located between the joint edges 1a, 1a. In addition, the uncured FRP tape layer 2 of the middle layer
Joint edge 2a of uncured FRP tape forming
The joint edge 3a of the uncured FRP tape forming the outermost uncured FRP tape layer 3 is also displaced in the axial direction. Furthermore, the three uncured FRP tape layers 1, 2, and 3 described above are adhered together by their adhesive properties when adjacent ones are attached to each other.
Therefore, the boundaries a and b between the layers shown in FIG. 1 cannot actually be distinguished. In other words, the above uncured
The FRP tube is integrated at all points in the circumferential and axial directions, and there will be no gaps or separation at the joints.

The uncured FRP tape forming the uncured FRP tape layers 1, 2, and 3 is made of ultraviolet-curable or thermosetting FRP and is molded into a tape shape, and has excellent corrosion resistance, flexibility, strength after curing, etc. Excellent in Ultraviolet curing type and thermosetting type are distinguished depending on whether the curing is caused by ultraviolet irradiation or heating. Further, the protective films 4 and 5 are held on the uncured FRP tape layers 1 and 3 by the adhesiveness of the uncured FRP tape. Since the inner and outer surfaces of the uncured FRP tube are sticky, covering both the inner and outer surfaces with protective tapes 4 and 5 prevents the inner surfaces from adhering to each other, and at the same time improves the handling of the uncured FRP tube. For the protective films 4 and 5, for example, Poval (PVA), which has excellent releasability, is used.

When using such an unhardened FRP tube as an inner lining material for a pipe, the unhardened FRP tube is flattened and inserted into the pipe, and then the unhardened FRP tube is inflated by air supply and brought into close contact with the inner surface of the pipe. . As mentioned above, the unhardened FRP tube has no joints anywhere in the circumferential or axial direction, so this air supply will cause the unhardened FRP tube to
The FRP tube will not tear and air will not leak from the gap. From this state, the uncured FRP tube is cured by ultraviolet irradiation or heating. In this case, it is necessary to close the end of the uncured FRP tube before supplying air. If necessary, peel off the protective films 4 and 5 from the uncured FRP tube after inserting it into the tube.
Only the uncured FRP tape layer is adhered to the inner surface of the pipe,
It is possible to harden it.

Next, a method for manufacturing an uncured FRP tube will be explained.

In FIG. 2, 100 is a rotating core that rotates at a constant speed in the direction of arrow B in conjunction with a drive source not shown. This rotating core 100 includes a plurality of uncured
FRP tapes 11, 12, and 13 are fed, and as the rotating core 100 rotates, these uncured FRP tapes are fed.
The tapes 11, 12, and 13 are sequentially wound in a spiral shape while joining the tape edges to form joint edges 1a, 2a, and 3a. As a result, the rotating core 10
Uncured FRP tape 11 fed to the base end of 0
The uncured FRP tape layer 1 formed by
The FRP tape 12 is wound to form an uncured FRP tape layer 2, and the uncured FRP tape 13 fed to the tip of the rotating core 100 is further wound onto this uncured FRP tape layer 2. unhardened FRP
A tape layer 3 is formed. In this case, uncured FRP
A subsequent uncured layer on the seam edge 1a of tape layer 1
Wrap around the center of FRP tape 12 and uncure it.
On the joint edge 2a of the FRP tape layer 2, approximately the center of the subsequent uncured FRP tape 13 is wound. In this way, the joint edges of the preceding uncured FRP tape layer are covered by the subsequent uncured FRP tape layer. As a result, the above-mentioned uncured FRP tape layers 1, 2, and 3 stick together due to their adhesive properties, and are integrated into an uncured FRP tape layer with the rotating core 100 as a core material.
FRP tube is formed. The thus obtained uncured FRP tube is pulled out from the rotating core 100 by a payout roller 110 disposed at the tip of the rotating core 100, deformed into a flat shape, and wound onto a take-up reel (not shown). In order to efficiently pull out the unhardened FRP tube from the rotating core 100, it is effective to suppress the friction between the rotating core 100 and the unhardened FRP tube. For this purpose, for example, the rotating core 100 may be tapered, or a large number of air injection holes may be formed on the outer surface of the rotating core 100, and the air ejected from the air injection holes may be used to connect the rotating core 100 to the Forming an air layer between the hardened FRP tube,
It is advantageous to apply a silicone-based lubricant to the rotating core 100 in advance or to continuously inject it.

Uncured FRP tape 11, 12, 13 mentioned above
As shown in FIG. 3, protective films 4 and 5 are held on both sides thereof. Of these, uncured
Protective film 5 on one side of FRP tape 11, protective films 4, 5 on both sides of uncured FRP tape 12
And the protective film 4 on one side of the uncured FRP tape 13 is made of these uncured FRP tapes 11, 12,
13 is peeled off from the tape immediately before being wound around the rotating core 100. For example, in order to peel off the protective films 4 and 5 from the uncured FRP tape 12, the protective films 4 and 5 are peeled off in a folded manner using, for example, suspenders 120 as shown in FIG. In the figure, 130 is a protective film take-up reel.

In this example, the case where the uncured FRP tape layer is wound in three layers is explained, but the number of layers is not limited to this, and for example, as shown in FIG. It may have three or more layers.

Furthermore, although the above manufacturing method is for the case where a protective film is previously held on the uncured FRP tape, it is also possible to use an uncured FRP tape that does not have a protective film held thereon. In this case, a protective film is spirally wound around the rotating core, and then multiple layers are placed on top of the protective film with the joint edge of the preceding uncured FRP tape covered by the subsequent uncured FRP tape. The uncured FRP tape may be spirally wound, and a protective film may be further spirally wound on the outermost layer of the uncured FRP tape.

〔Effect of the invention〕

Since the unhardened FRP tube of the present invention has no joints anywhere in the axial direction or circumferential direction, air leakage is unlikely to occur even if air is supplied into the inside of the unhardened FRP tube to inflate the unhardened FRP tube. Therefore, it can be suitably used as an inner lining material for pipes such as existing pipes.

[Brief explanation of drawings]

Fig. 1 is an enlarged cross-sectional view of the main part of an uncured FRP tube according to an embodiment of the present invention, Fig. 2 is a schematic plan view for explaining the method of an embodiment of the present invention, and Fig. 3 is a cross-sectional view of an uncured FRP tape. FIG. 4 is a schematic front view showing a protective film peeling means, and FIG. 5 is an enlarged sectional view of a main part of an uncured FRP tube of another embodiment. 1, 2, 3... uncured FRP tape layer, 1a,
2a, 3a... Joint edge, 4, 5... Protective film, 11, 12, 13... Uncured FRP tape,
100...Rotating core.

Claims (1)

[Scope of Claims] 1. An uncured FRP tube in which multiple layers of uncured FRP tape are wound in a spiral shape, and the upper and lower uncured FRP tape layers are integrated by their adhesiveness, which is a spiral tube. The end surfaces of uncured FRP tapes of the same layer wound in a shape are brought together and joined, and the joint edges are misaligned in the axial direction between the upper and lower uncured FRP tape layers, An uncured FRP tube for inner lining, characterized in that a protective film is held on the inner surface of the innermost uncured FRP tape layer and the outer surface of the outermost uncured FRP tape layer.