JPS62198447A - Manufacturing device for composite tube - Google Patents

Abstract

PURPOSE:To obtain a composite tube in which an uniform thick plastic layer is clad on the inner peripheral surface of a metallic round tube, by a method wherein the titled device is provided with a round tube forming machine, forming a belt-type metallic sheet into a round tube and coating a plastic layer on the inner peripheral surface of the round tube, and a unevenness regulating machine, moving said round tube into a direction intersecting orthogonally to a conveying direction from said round tube forming machine and changing a relative position between the round tube and the plastic layer. CONSTITUTION:A metallic sheet 11, formed into U-shape by a U-shape forming machine 3 and heat-treated by a heating unit 22, is plied between the connecting part 41a of an inner mold 41 and an outer mold 42, is aligned by introducing it into a clearance 42m in the outer mold 42, is formed into a round tube 12 having roundness and is guided to the outside of the outer mold 43. The round tube, whose plied part is welded by a welding means 5, is coated with a plastic layer by extruding molten resin from a nozzle 41h onto the inner peripheral surface thereof during passing the tip end of the forming section 412 of the inner mold 41. An unevenness regulating machine 6 moves the round tube 12 vertically and horizontally to regulate and change a relative position between said round tube 12 and the forming section 412 of the inner mold 41, whereby the thickness of the plastic layer on the inner peripheral surface of the round tube can be uniformized.

Description

[Detailed description of the invention]

TECHNICAL FIELD The present invention relates to a composite pipe manufacturing apparatus for forming a band-shaped metal sheet into a composite pipe whose inner peripheral surface is coated with a plastic layer. (Prior Art) As an apparatus for manufacturing a composite pipe in which the inner peripheral surface of a metal pipe is coated with a plastic layer, for example, French Patent No. 24636 is used.
It is disclosed in No. 73. This device uses a U-shaped forming machine to bend a band-shaped metal sheet into a U-shape so that each side extending in the longitudinal direction faces each other, and then bends this U-shaped metal sheet into a circular tube forming machine. This makes it a circular tube with a perfect circular cross section. Then, the molten resin is extruded to form a plastic layer on the inner peripheral surface of the two circular tubes. The cylindrical tube forming machine has a cylindrical inner die and an outer die that are fitted into each other so that a cylindrical gap (cavity) is formed within this gap. By passing a metal sheet bent in a U-shape, a metal sheet with a U-shaped cross section is created!・Overlap each side end of the opening edge to form a circular tube. Also, the molten resin is passed through the inner mold, and the molten resin is extruded in a cylindrical shape from the downstream end of the inner mold in the metal sheet conveying direction onto the inner peripheral surface of the molded circular tube. It is a composite pipe covered with a plastic layer. The cylindrical inner mold has its downstream end located within the circular pipe to be molded, and it is necessary to extrude the molten resin from the end into a cylindrical shape.Therefore, there is no way to support the end and the mold is left in a cantilevered state. Ru. For this reason, if the inner mold becomes long, there is a risk that it will bend, and the plastic layer formed from the extruded molten resin will not have a uniform thickness. When these circular pipes are connected using a joint that is tightened on the inner and outer surfaces, the joints are not placed in concentric positions because the wall thicknesses are uneven. Therefore, the pipe cannot be tightened uniformly in the circumferential direction, causing water leakage. In addition, if the plastic layer becomes thin, the internal pressure applied to the composite pipe will cause damage when the composite pipe is used for various purposes.
There is a risk that the composite pipe will be damaged from the thin walled portion. (Problems to be Solved by the Invention) The present invention solves the above-mentioned conventional problems, and its purpose is to provide a composite pipe in which the inner peripheral surface of a metal circular pipe can be coated with a plastic layer of uniform thickness. Our goal is to provide manufacturing equipment for Another object of the invention is. The thickness of the plastic layer that coats the inner circumferential surface of the circular tube. The object of the present invention is to provide an apparatus for manufacturing a composite pipe that can uniformly adjust the IF and feeding of the circular pipe without stopping. (Means for Solving the Problems) The composite pipe manufacturing apparatus of the present invention, when forming a band-shaped metal sheet into a circular pipe, extrudes molten resin in a cylindrical shape onto the inner circumferential surface of the metal sheet to form the inner circumferential surface. A circular tube forming machine to be coated with a plastic layer and a circular tube led out from the circular tube forming machine are moved in a two-dimensional direction perpendicular to the conveying direction, and the circular tube and the inner circumferential surface of the circular tube are coated with a plastic layer. The above object is achieved by including a thickness unevenness adjusting machine that changes the relative position with respect to the plastic layer to be covered. (Example) Examples of the present invention will be described below. The composite tube manufacturing apparatus of the present invention manufactures, for example, a composite tube in which the inner and outer peripheral surfaces of a metal tube are coated with a plastic layer. The apparatus for manufacturing the composite pipe is as shown in FIG. Band-shaped metal sheet 10 pulled out from uncoiler 1
3. The metal sheet is subjected to surface treatment in a surface treatment step 21, and then the metal sheet is subjected to a U-shaped molding machine 3 of the present invention. First, it is bent and formed into a U-shape in which the longitudinally extending side portions face each other. The metal sheet 11 bent into a U-shape is further heat-treated by a heating device 22. A circular tube forming machine 4 forms a circular tube 12 having a perfect circular cross section. The closed part of the circular tube 12 formed by the circular tube forming machine 4 is welded by the welding machine 5, and the closed part of the circular tube 12 is welded by the welding machine 5. 1
Molten plastic is extruded onto the inner circumferential surface of 2 to coat the inner circumferential surface with a plastic layer. A thickness unevenness adjuster 6 for a plastic layer coated on the inner peripheral surface of the circular tube 12 by an inner surface resin coating device 40 is disposed downstream of the weld a5. On the downstream side of the thickness unevenness adjuster 6, an outer surface coating device 7 for coating the outer circumferential surface of, for example, a circular pipe 12 with plastic is disposed. Further, on the downstream side thereof, there is a cooling tank 8 for cooling the circular tube 13 whose inner peripheral surface and outer peripheral surface are covered with a plastic layer. A take-up machine 91 for taking off the cooled circular pipe (composite pipe) 14. A winder 92 for recovering the composite pipe 14 is sequentially arranged. Pick up [9
1 performs all conveyance from pulling out the metal sheet 10 from the uncoiler 1 to forming it into a composite pipe 14. Cylindrical acid constituting the composite pipe manufacturing apparatus of the present invention) F4! S
4 has an inner mold 41 and two outer molds 42 and 43, as shown in FIGS. 2 to 4. The inner mold 41 has a cross section

[Support part 4 located on the upstream side in the conveyance direction of the J-shaped metal sheet 11
11, a tubular molded part 412 extending downstream from the support part 411, and a core part 413 that fits inside the molded part 412. At the lower part of the support part 411, a continuous part 41 having a U-shaped cross section is fitted into the U-shaped metal sheet 1-11.
a is formed. A notch 41b is provided in the upper part of the continuous part 41a so as not to come into contact with the upper end of the U-shaped metal sheet 11 that is inclined toward the center. 41b is formed. A molded portion 412 extends downstream from the continuous portion 41a. The continuous portion 41a
A through hole 41i communicating with the molded part 412 is formed in the molded part 412, and the core part 413 is inserted through the through hole 414 and the molded part 412. A spacer 44 having a U-shaped cross section is fitted into the continuous portion 41a with a predetermined gap 442 therebetween. The spacer 44 is fitted inside the support mold 45. Metal sheet 11 formed into a U-shape within the gap 442
passes. The core portion 413 has a large diameter portion 41c that is in close contact with the through hole 41i of the continuous portion 41a, and a small diameter portion 1.1d that is inserted into the tubular molded portion 412. The small diameter portion 41d has a predetermined gap 41c from the inner circular surface of the molded portion 412. The gap 41e is a resin passage 41 formed in the support part 411.
A core cap 111g is attached to the tip of the small diameter portion old d of the core portion 413.
g fits into the opening at the tip of the molding part 412, and the nozzle 4t
It forms h. Molten resin is press-fitted into the resin passage 41f of the support portion 411. The press-fitted molten resin passes through the gap 41e between the molded part 412 and the core part 413 and is extruded in the circumferential direction from the nozzle 41h. This molded portion 412. The inner surface resin coating device 40 is configured by the core portion 413 and the core cap 41g. The support mold 45 into which the spacer 44 is fitted has a pair of arm portions 451 and 451 extending downstream. Each arm portion 451° 451 has a rectangular cross section and is arranged parallel to each side of the molded portion l112. Tip of each arm 451 0:;1
The section is located in the middle of the molding section 412. At the tip of each arm portion 451, 451, two outer molds 42 and 43 are arranged in parallel in the conveying direction of the metal sheet 11. Hermaphrodite types 42 and 43 have roughly the same structure. The upstream outer mold 42 has housing halves 421 and 422 that are divided in the vertical direction and liners 423 and 424 that are fitted into each housing halves 42L422. On the outside of each side of the upper housing half 421, there are notches 42a, 42 that can be engaged with the arms 451, 451 of the support mold 45.
a are formed respectively. The housing half 421
A recess 42b whose inner circumferential surface is semi-cylindrical and opens downward is formed in the center of the lower part of the recess 42b along the conveying direction of the metal sheet. A boss portion 42e is formed in the center of the recess 42b, and the semi-cylindrical liner 42 is disposed in the recess 42b.
3 is fitted in a state where it is engaged with the boss portion 42e. The liner 423 has a smooth inner circumferential surface, and is fitted onto the outer circumferential surface of the molded part 412 of the inner mold 41 with a predetermined gap therebetween. The diameter of the downstream end of the liner 423 gradually increases toward the upstream side. The liner 423
As the material, synthetic resins having excellent heat resistance, abrasion resistance, and sliding properties with metal sheets, such as fluororesin and aromatic polyester resin, are used. The housing half 421 has a liner 423 in the recess 4.
2b, each arm portion 45■ of the support mold 45. The notches 42a, 42a are respectively engaged with the upper part of the arm 451, and the arm 451 is constructed between the arms 451, 451.
1,451 and is fixed with a screw. The lower housing half 422 has the same structure as the upper housing half 421 except that the lower part is reversed. Notches 42c, 42c and boss portion 42f on the outside of each side
The inner peripheral surface has a semi-cylindrical recess 42d. The liner 4 having a semi-cylindrical inner peripheral surface is attached to the fourth part 42d.
It is tightly fitted. 8-liner 424. Liner 4 attached to upper housing half 421
23, the inner circumferential surface may have a cylindrical shape. The material of the liner 424 is also the same as that of the upper liner 23. Further, the diameter of the upstream end of the liner 424 gradually increases toward the upstream side. The lower half of the housing 422 is placed in a state where the liner 424 is fitted into the recess/12d, and the supporting mold 45 is
The notches 42r, 42c are engaged with the lower portions of the arm portions 451, 451 of the liner 424 so that the liner 424 opens upward. Then, in the lower region of the upper housing half 421, the liners 423 and 424 are aligned so that the inner peripheral surface forms a cylindrical passage. The housing half 422 is screwed and fixed to the lower surface of each arm 45L451. Both housing halves 421 and 422 have arm parts 451 and 4
When secured to 51, liners 423 and 424
The molded portion 412 of the inner mold 41 is fitted concentrically with the outer peripheral surface of the molded portion 412 with a predetermined gap 42m therebetween. The outer mold 43 located on the downstream side has housing halves 431 and 432 . similar to the outer mold 42 on the upstream side. liner 433
and 434. The nuclear outer mold 43 has the same structure as the upstream outer mold 42, so a description thereof will be omitted. The nuclear outer mold 43 is in close contact with the upstream outer mold 42 and the supporting mold 4
It is attached to both arm parts 45L 451 of 5. liner 4
33 and 434 are fitted onto the outer circumferential surface of the molded portion 412 of the inner mold 41 with a predetermined gap 43m therebetween. The molding portion 412 of the inner mold 41 extends from the outer nuclear mold 43. The diameter is slightly enlarged, and a stepped portion 41x is formed in a portion facing the downstream end of the outer mold 43. The metal seam H1 is formed into a U-shape by the U-shape forming 53 and heat-treated by the heating device 22. The continuous portion 41a of the inner mold 41 of the circular tube forming machine 4 and the spacer 4
Five people are placed in the gaps 42m and 43m between the outer molds 42 and 43 and the molding part 412 of the inner mold 41 through the gap 442 between the mold and the inner mold 41. The U-shaped metal sheets 11 are overlapped within the free space between the continuous portion 41a of the inner mold 41 and the outer mold 42, and are introduced into the gap 42m within the outer mold 42. Then, while passing through the gaps 42m and 43m, the overlapping parts of the metal sheets are aligned to form a perfect circular tube 12,
It is derived from the outer mold 43. The free space is preferably set at a distance (distance) that is at least twice the outer diameter of the circular tube to be formed. The inner diameter of the circular tube 12 guided out from the outer mold 43 is defined by the enlarged diameter portion on the distal side of the stepped portion 41× of the molding portion 412. Each liner 423, 424 and 433, 434 of each outer mold 42 and 43 is removable from the housing half 422 and 431, 432, respectively, and when each liner becomes worn, it can be replaced with a new liner. During this replacement, while the U-shaped metal sheet 11 is being transported and formed into the circular tube 12, the housing half of either the upstream or downstream outer mold 42 or 43 is replaced with the support arms 451, 451. This is done by removing it from the After each liner of one outer mold is replaced and each housing half is attached to the support arms 451, 451, each liner of the other outer mold is replaced by similar scraping. Therefore, each liner can be replaced without interrupting the molding of the circular tube 12. Further downstream of the outer mold 43 on the downstream side, a welding means 5 is provided to weld the overlapped portions of the circular tubes 12 obtained by the one-cylindrical tube forming a4. This welding means 5 does not need to be special, and for example, an ultrasonic welding machine or the like may be used. While the welded circular tube 2 passes through the tip of the molded part 412 of the inner mold 41, the molten resin is pushed out from the nozzle 41h formed at the tip to the inner peripheral surface of the welded circular tube 12-. The surrounding surface is covered with a plastic layer. Thickness unevenness adjustment at the tip of the core base 4113 of the inner mold 41 2) 16
is arranged so that it fits externally. The thickness unevenness adjuster 6 is
As shown in FIGS. 9 and 10, the vertical adjustment section 6
1 and a horizontal direction adjustment section 62. Vertical adjustment section 6
1 is located on the downstream side of the circular tube 12 in the conveying direction. A pair of guide rods 611 and 611 and a block body 6
12. The guide rods 611 and 611 are provided vertically on each side of the conveyance area of the two-circular tube 12, respectively. Two guide rods 611 and 611 pass through each side of the block body 612, and the block body 612 can slide in the vertical direction while being guided by both guide rods 611 and 611. Two through holes 613 are formed in the center of the block body 612. The through hole 613 is larger than the outer diameter of the circular tube 12. The block body 612 is attached to the lower end of a vertically disposed adjustment rod 614. An adjustment section 615 is externally fitted and screwed onto the upper end of the adjustment rod 614, and by rotation of the adjustment section 615, the adjustment rod 61
4 is threaded in the vertical direction. The block body 612 is slid in the vertical direction along the guide rods 611, 611. A horizontal adjustment section 62 is provided on the upstream side of the block body 612.
is installed. The horizontal adjustment section 62 has a pair of guide rods 621 and 621 and a main body section 622. The guide rods 62L621 are installed horizontally above and below the transport area of the circular tube 12, respectively, and are integrally attached to the block body 612 of the vertical adjustment section 61. Both guide rods 621 and 621 have two main body parts 6
The main body portion 622 is guided by two guide rods 621 and 621 and can slide in the horizontal direction. One end of a horizontally disposed adjustment rod 624 is attached to the main body 622 . An adjustment part 625 is externally fitted and screwed to the other end of the adjustment rod 624, and the rotation of the adjustment part 625 causes the adjustment rod 624 to be screwed in the horizontal direction, and the main body part 622 is moved to the guide rod 62.
1 and 621 in the horizontal direction. Two through holes 626 are formed in the center of the main body portion 622 . The through hole 626 is fitted onto the tip of the molding part 412 of the inner mold 4. A sliding member 627 having a flange portion formed on the upstream side is fitted into the through hole 626 . The sliding material 6
27 is a synthetic resin 1, such as a fluorine resin, which has good wear resistance, heat resistance, and sliding properties with respect to the metal circular tube 12. Aromatic polyester resin or the like is used. In addition, instead of such a liner, a plurality of drum-shaped rows with a concave center are rotatably arranged in one through hole 626 so as to create a circular space in the center. The circular tube 12 may be inserted into the central space. In this case, since each roller rotates when it comes into contact with the circular tube 12, wear on its peripheral surface can be prevented and the trouble of replacing the liner can be eliminated. The uneven thickness adjustment rj! Reference numeral 6 denotes a circular tube 12 formed into a circular tube shape by the 1-yen 5-tube forming machine 4 and whose inner peripheral surface is coated with plastic through the through hole 626 of the horizontal adjustment section 62 and the through hole of the vertical adjustment section 61. 613 and is guided to the outer surface coating mold 7. Then, the uneven thickness A11 adjuster 6 moves the circular tube 12 vertically and horizontally, and
2 and the molding part 412 of the inner mold 41 is adjusted and changed to make the thickness of the plastic layer covering the inner circumferential surface of the circular tube 12 uniform. It is preferable that the thickness unevenness adjuster 6 is disposed so as to fit over the tip of the core mouthpiece 41g, since the thickness unevenness can be adjusted by a minute adjustment, but it is preferable that the thickness unevenness adjuster 6 is disposed downstream from this position. There may be. The circular tube 12 led out from the thickness unevenness adjuster 6 is turned into a circular tube 13 whose outer peripheral surface is coated with a plastic material by a predetermined outer surface coating device 7 . The circular tube 13 is cooled in a cooling tank 8 and made into a composite tube 14. The composite pipe 14 is taken off at take-off [91]. The pulling machine 91 pulls out the metal sheet 10,
All conveyance is performed until formation into the composite tube 14. The composite tube 14 is collected by a winder 92. (Effects of the Invention) As described above, since the composite pipe manufacturing apparatus of the present invention includes the thickness unevenness adjusting device, it is possible to coat the inner circumferential surface of the two circular pipes with a plastic layer having a uniform thickness. Therefore, there is no risk that part of the plastic layer will become too thin or too thick. As a result, even when such composite pipes are connected using a fastener that tightens the inner and outer surfaces, the joint and the composite pipe are arranged in a concentric position and are reliably tightened and connected. Therefore, there is no risk of water leakage even when water or the like is passed through the pipe, and there is no risk of damage to the composite pipe due to internal pressure applied to the composite pipe even when the composite pipe is used for various purposes. Productivity is improved because uneven thickness can be adjusted without stopping the conveyance of the metal sheet. ↓-y field rotor (fatigue Figure 1 is a schematic diagram of the composite pipe manufacturing equipment, Figure 2 is a vertical cross-sectional view of the circular tube forming machine, Figure 3 is the m-n'r of Figure 2) 4 is a sectional view taken along line IV-IV in FIG. 2, FIG. 5 is a side view of the gingival adjuster, and FIG. 6 is a front view showing a part of it in section. 3. ... U-shaped molding machine, 4 ... Circular tube molding machine, 6 ...
Thickness unevenness adjuster, 10...metal seam 1-. 11...Metal sheet bent into a U-shape! -, 12, 13... circular tube,
14...Composite pipe, 41...Inner mold, 42.43.
...outer mold, 412...molding part, 413...core part,
42L422, 431.432...Housing half-closed, 7I23°424, 433.434...Liner, 61...Vertical direction adjustment part. 62...Horizontal direction adjustment part, 61L621...Guide rod, 622...Main body part, 626...Through hole, 6
27...Sliding material. Figure 3 Figure 4

Claims (1)

[Scope of Claims] 1. A circular tube forming machine that extrudes molten resin into a cylindrical shape onto the inner circumferential surface of the belt-shaped metal sheet to cover the inner circumferential surface with a plastic layer when forming a circular tube; The circular tube led out from the circular tube forming machine is moved in a two-dimensional direction perpendicular to the conveying direction thereof, and the relative position of the circular tube and the plastic layer coated on the inner peripheral surface of the circular tube is changed. A composite pipe manufacturing device having a thickness unevenness adjusting machine and the following. 2. The circular tube forming machine has an inner mold from which molten resin is extruded in the circumferential direction from the downstream end of the metal sheet in the conveyance direction, and an outer mold that is fitted onto the outside with a predetermined circular gap between the inner mold and the inner mold. An apparatus for manufacturing a composite pipe according to claim 1, comprising a mold. 3. The thickness unevenness adjusting machine has a main body portion provided with a through hole through which a circular tube passes, and a means for moving the main body portion in a two-dimensional direction perpendicular to the conveying direction of the circular tube. The apparatus for manufacturing a composite pipe according to item 2. 4. The composite pipe manufacturing apparatus according to claim 3, wherein the main body is disposed so that its through hole is fitted onto the distal end of the inner mold. 5. The composite pipe manufacturing apparatus according to claim 4, wherein a removable sliding member is fitted into the through hole of the main body. 6. The composite pipe manufacturing apparatus according to claim 4, wherein the through hole is provided with a roller that rotates in contact with the circular pipe being conveyed.