JPH02143835A - Manufacture of synthetic resin reinforced tube - Google Patents

Abstract

PURPOSE:To continuously produce large bore synthetic resin reinforced tube, the surface of which is almost smooth, which has uniform wall thickness and is excellent in pressure resistance, by a method wherein both band-like sheeting made of thermoplastic resin and metal tape, on the surface of which adhesive is applied, are heated and laterally shifted one another so as to be spirally wound round an imaginary cylinder-like revolving shaft body and, after that, fixed by pressure with a press roll. CONSTITUTION:Two sheets of bank-like surface layer forming sheeting 1, each of which is made of low density polyethylene sheet having a thickness of about 0.5mm, four sheets of band-like laminated intermediate layer forming tapes 2, each of which consists of high density polyethylene sheet and low density polyethylene sheet each having a thickness of about 1mm and a width half times or less as wide as the width of the sheeting 1 and one sheet of steel tape 3 having a thickness of about 0.5mm and a width half times or less as wide as the width of the sheeting 1 are heated by being passed through a heating zone B. After that, both the tapes 2, which are laterally shifted one another so as to be vertically located in two stages, and the metal tape 3, which is interposed between said two stages of the tapes 2 located vertically, are put between the sheets 1 so as to be spirally wound round an imaginary cylinder-like revolving shaft body C. At this time, the previous wound tapes and the following wound tapes are wound so as not to be put one upon another or so as to be disposed in an array and then urgingly fused with a press roll D and finally hardened through cooling.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for manufacturing synthetic resin reinforced pipes used as water supply and drainage pipes for agricultural and civil engineering, industrial water supply and drainage pipes, etc. A large-diameter synthetic resin pipe with a substantially smooth surface, uniform wall thickness, and excellent pressure resistance, internal pressure resistance, and moisture resistance is made from band sheets, thermoplastic resin band tape, and metal tape near the construction site. The present invention relates to a method for manufacturing a synthetic resin reinforcing tube that can be efficiently and continuously molded.

(Prior Art) Conventionally, as a method for producing this type of synthetic resin reinforced tube, a method has been used in which a tube body is produced by spirally winding a fat strip and fusing or gluing the same.

[Problem that the invention seeks to solve]

However, the above manufacturing method uses a single leaf of the belt when winding the belt in a spiral manner on the upper surface of the virtual cylindrical rotating shaft, and moreover, the belt that is wound earlier and the belt that is wound later are different from each other. Because the tube is formed by winding the tubes so that they overlap each other at the sides, when using thin-walled strips, the width of the overlapping portion must be widened in order to maintain a certain thickness, but in general use However, when manufacturing large-diameter synthetic resin reinforcing pipes, the equipment becomes large, and a die that matches the size of the pipe body must be prepared each time, resulting in high manufacturing costs. there were.

Therefore, when manufacturing large-diameter synthetic resin pipes, not only is it not possible to obtain a uniform wall thickness of the metal-reinforced synthetic resin on the virtual cylindrical rotating shaft, but there are also problems such as steps occurring in the overlapping part. It had a point.

The present invention aims to eliminate the drawbacks of the conventional methods described above. It is an object of the present invention to provide a method for manufacturing a synthetic resin reinforcing pipe that enables efficient and continuous molding of the resin pipe.

[Means for solving problems]

The present invention was invented in view of the above, and includes a two-lobed thermoplastic resin strip sheet pre-formed to form a surface layer and a multi-lobed thermoplastic resin strip tape pre-formed to form an intermediate layer. and at least one sheet of metal tape, the surface of which is coated with an adhesive, is heated through a heating region to a temperature above the softening point and below the melting point of the strip sheet and the strip tape, so that both sides of each sheet are positioned on the same line as each other. The present invention relates to a method for manufacturing a synthetic resin reinforcing pipe, which is characterized in that it does not cause any damage.

Hereinafter, the features of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partially cutaway perspective view illustrating the manufacturing process of the present invention, FIG. 2 is a partially cutaway sectional view of the same, and FIG. Figure 3 is a partially cutaway plan view of the same as above, and 1 in the figure is a thermoplastic resin band-shaped sheet forming the surface layer of the tube body A, and is a polyethylene sheet that has been previously formed into a long shape with a predetermined thickness and width. A belt-shaped tape made by winding up a belt-shaped sheet based on a thermoplastic resin sheet, such as a polypropylene sheet, into a roll, which is wound once in a spiral shape, and which has been turned at least once before each round. and the belt-shaped tape wound later are wound so as to be arranged side by side with each other without polymerizing to form a tube, and at the stage when the belt-shaped sheet and the belt-shaped tape are still at a temperature above the softening point and below the melting point, the virtual A tubular body with a substantially smooth surface is continuously manufactured by pressure welding with a pressure roll that is in contact with a cylindrical rotating shaft, cooling and hardening it, and winding each piece into a roll shape in the same manner as Part 1. 3 is a metal tape interposed between the band-shaped tapes 2, which is made by applying an adhesive 4 to the surface of a tape-shaped material made of stainless steel, steel, aluminum, etc. Sheet 1, strip tape 2, and metal tape 3 are heated in area B using a heat source such as a wind blower or an infrared lamp.
is heated to a temperature above the softening point and below the melting point of the strip tape 2 and the metal tape 3, and then shifted horizontally between the strip sheets 1 so that the respective side portions are not located on the same line with each other. While interposing the band tape 2 and the metal tape 3, the virtual cylindrical rotary shaft C is simultaneously supplied at an inclined angle to the side circumferential surface of one end thereof, and is wound spirally, and at least first is wound during this winding. The rolled tape 2 and the rolled tape 2 are wound so that they are arranged parallel to each other without overlapping, and the front and rear ends of the tube are rotatably supported on the base plate a and the bearing plate, respectively. The entire combination substantially constitutes one virtual cylindrical rotating body, and each roll C(a), C mountain), , , C(i) has a bearing plate relative to the substrate a. Each roll C(a) C(b), which is supported by the substrate a,
, C(i) is supported in a bearing plate at one end, and by shifting the bearing point at the other end, that is, each o-le C
By twisting and tilting (a), C(b), , , C(i) around the axis of the virtual cylindrical rotating shaft C, the belt-shaped sheet l, the belt-shaped tape 2, and the metal chain C are
The tubular body A is formed by pressure-welding with a pressure roll D that is in contact with and cooling and hardening while transferring it to the other end side.

The virtual cylindrical rotating shaft body C shown in Fig. 1 is composed of a plurality of rolls C(a), C(b), , , C(i
) from the set, each row /l/ C(a)
, C(b)1. , C(i) are arranged in parallel so as to maintain a constant distance between adjacent rolls along one virtual circumference, each of which has a sprocket C at its shaft end, and a chain attached to the sprocket C. Each roll C(a
), C (c).

C(i) is made to rotate in the same direction at a constant speed.

In addition, when the band-shaped sheet 1 used in the present invention is wound spirally around the virtual cylindrical rotating shaft C in order to improve the watertightness, the band-shaped sheet 1 that is previously wound is
and later) The tape is made thinner and wider than the strip tape 2 so that the rolled tape 1 can be wound so that it overlaps at the side, and the step difference in the overlapped portion after one roll is extremely small. It is preferable to form the band-shaped tape 2 so that it has a relatively thick thickness within the area that is to be punched. Therefore, as shown in FIG. It is preferable to use a composite tape layered with a thermoplastic resin having a relatively low softening point.

A metal tape 3 made of a steel sheet whose size is one-half or less of the belt-shaped sheet L is passed through a heating zone B using hot air as a heat source, and heated to a temperature higher than the softening point and lower than the melting point of the belt-shaped sheet L and the belt-shaped tape 2. By shifting the positions of the four-lobed strip tapes 2 in the horizontal direction so that they are not located on the same line, the two-lobed strip tapes 2 arranged side by side are positioned in upper and lower two stages, and the strip tapes 2 are The metal tape 3 is interposed between the belt-like seams I and 1, and the tape is spirally wound once on the virtual cylindrical rotating shaft C, with the metal tape 3 interposed between them. For example, two strip-shaped sheets l made of a low density polyethylene sheet with a thickness of 0.5 m are pre-formed and rolled into a roll to form a surface layer, and a two-lobed sheet l made of a low-density polyethylene sheet with a thickness of 0.5 m is pre-formed and rolled to form an intermediate layer. A four-lobed strip tape 2 made of a laminated sheet of a high-density polyethylene sheet and a low-density polyethylene sheet with a thickness of 1 m+* and a width of less than half of the strip sheet L and a thickness of 0. 5 mm in width to form a tube A, and when the tube A is still at a temperature above the softening point and below the melting point, it is pressed and melted with a pressure roll D that is in contact with a virtual cylindrical U-rolling shaft C. By cooling and hardening, a tubular body A having a substantially smooth surface as shown in FIG. 5 was formed.

[Effects of the Invention] As is clear from the above, the present invention has two thermoplastic resin strip sheets preformed to form a surface layer and a plurality of thermoplastic resin strip sheets preformed to form an intermediate layer. The tape and at least one sheet of metal tape, the surface of which is coated with an adhesive, are heated through a heating region to a temperature above the softening point and below the melting point of the strip-shaped sheet and the strip-shaped tape, so that both sides of each tape are aligned with each other. ! A plurality of intermediate layers and reinforcing layers are simultaneously applied 1!1 times in a helical manner on a virtual cylindrical rotating shaft while shifting their positions in the lateral direction and interposing a band-like tape between the band-like sheets to prevent moldability,
It has characteristics such as significantly improved pressure resistance and internal pressure resistance, and further improved rice paddy properties because the layered strip sheets and strip tape are wound in different positions. It is.

[Brief explanation of the drawing]

1 to 3 show embodiments of the present invention; FIG. 1 is a partially cutaway perspective view explaining the manufacturing process of the present invention; FIG. 2 is a partially cutaway sectional view of the same; and the third tape are arranged in parallel with each other without polymerizing (and are wound to form a tube body,
From a configuration in which the band-shaped sheet and the band-shaped tape are still at a temperature above the softening point and below the melting point, and are pressure-fused by a pressure roll that is in contact with a virtual cylindrical rotating shaft body, and are cooled and hardened to form a tube body. This makes it possible to continuously mold a tube with a uniform initial wall thickness and a substantially smooth surface without the step difference that occurs in conventional polymerization. FIG. 5 shows a partially enlarged sectional view of a tube formed according to the present invention. l - Band-shaped sheet 2 - Band-shaped tape 3 - Metal tape A - Tube B - Heating area C - Virtual cylindrical rotating shaft body - Press roll

Claims (5)

[Claims] (1) At least two thermoplastic resin strip sheets preformed to form a surface layer, a plurality of thermoplastic resin strip tapes preformed to form an intermediate layer, and an adhesive coated on the surface. A sheet of metal tape is heated through a heating region to a temperature above the softening point and below the melting point of the strip-like sheet and tape, and the strip-shaped sheet is shifted in the horizontal direction so that both sides are not located on the same line with each other. The sheets are wound spirally on a virtual cylindrical rotating shaft with a band tape interposed between the sheets, and during this winding, at least the band tape wound first and the band tape wound later are mutually bonded without overlapping. The belt-shaped sheet and the belt-shaped tape are wound in parallel to form a tube body, and when the belt-shaped sheet and the belt-shaped tape are still at a temperature higher than the softening point and lower than the melting point, the belt-shaped sheet and the belt-shaped tape are pressed and melted with a pressure roll that is in contact with a virtual cylindrical rotating shaft. 1. A method for manufacturing a synthetic resin reinforcing tube, which comprises continuously manufacturing a tube body having a substantially smooth surface by coating and cooling and hardening the tube. (2) The method for manufacturing a synthetic resin reinforced pipe according to claim 1, characterized in that a steel sheet is used as the metal sheet. (3) When winding the belt-like sheet in a spiral shape on the virtual cylindrical rotating shaft, the belt-like sheet is wound so that the first-wound belt-like sheet and the second-wound belt-like sheet overlap at the sides. A method for manufacturing a synthetic resin reinforced pipe according to claim 1. (4) The method for manufacturing a synthetic resin reinforcing tube according to claim 1, characterized in that the belt-shaped sheet is made thinner and wider than the belt-shaped tape. (5) A method for manufacturing a synthetic resin reinforced pipe according to claim 1, characterized in that a composite tape consisting of a laminate of a high-density polyethylene tape and a low-density polyethylene tape is used as the band-shaped tape.