JP3477736B2 - Method and apparatus for manufacturing lining 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 lining having a hot melt adhesive layer formed on the outer peripheral surface thereof, such as a vinyl chloride resin pipe for lining for covering the inner wall surface of a steel pipe such as a water pipe or a drain pipe. The present invention relates to a manufacturing method of a tubular body and a manufacturing apparatus thereof.

[0002]

2. Description of the Related Art In recent years, vinyl chloride resin pipes have been lined on the inner surface of steel pipes for water supply and drainage in buildings, etc., to provide both the strength of iron and the corrosion and chemical resistance of vinyl chloride. A lining steel pipe is used that has both advantages.

As a method for producing this lining steel pipe, an adhesive is applied to the outer peripheral surface of a vinyl chloride resin pipe, the adhesive is inserted into the steel pipe, and the diameter of the steel pipe is reduced by cold working such as drawing. , A method in which a steel pipe and a vinyl chloride resin pipe are pressed together, or a heat-expandable vinyl chloride resin pipe with an adhesive applied to the outer peripheral surface is inserted into the steel pipe and then heated to form the vinyl chloride resin pipe. There is a method of adhering and fixing to the inner surface of the steel pipe by expanding it.

There are various adhesives used to bond the steel pipe and the vinyl chloride resin pipe, such as water-soluble, solvent-type and hot-melt adhesives, but they are easy to handle at room temperature, and have good adhesive performance and adhesive strength. A hot-melt adhesive is generally used because of its good quality.

As a method of applying the hot melt adhesive to the outer peripheral surface of the vinyl chloride resin pipe, conventionally, for example, a hot melt adhesive heated and melted at 180 ° C. is filled in a tank, A vinyl chloride resin pipe cut and molded to a predetermined length was passed through both openings formed on both sides of the tank and sent in one direction, and when the pipe came out of the outlet, it was provided at this outlet A fixed amount of hot-melt adhesive was applied to the outer peripheral surface of the vinyl chloride resin pipe by an iron handle ring to obtain a vinyl chloride resin pipe for lining.

[0006]

However, in the above-described method for manufacturing a vinyl chloride resin pipe for lining,
A vinyl chloride resin-based pipe that had been cut and shaped to a predetermined length was used, and after this pipe was connected with another member, it was placed in an adhesive tank to form an adhesive layer on the outer peripheral surface of the pipe body. However, in the manufacturing device by this method, due to the structure of the adhesive tank,
Only hot-melt adhesives with low viscosity and low softening point can be used as the adhesive filled in the tank, so the outer peripheral surface of the pipe after forming the adhesive layer is sticky at room temperature. In order to prevent dust from adhering to the surface of the adhesive layer, an inorganic fine powder was attached to the surface of the adhesive layer for post-processing. That is, there is a drawback that the number of steps is large, such as a step of connecting vinyl chloride resin pipes and a step of applying fine powder.

Further, in the above-described manufacturing method and manufacturing apparatus, since the tubular bodies that have been cut in advance are connected, the outer peripheral surface does not become a uniformly continuous surface, and the adhesive layer can be formed to have a uniform thickness. It is impossible and there is a problem that unevenness occurs.

Therefore, in order to solve the above problems, the present invention applies a hot melt adhesive evenly to the outer peripheral surface of a pipe such as a vinyl chloride resin pipe so that the thickness is uniform. An object of the present invention is to provide a manufacturing method and a manufacturing apparatus for a lining tube, which can form a layer and easily obtain a high-quality lining tube.

[0009]

Means for achieving the above object will be described below with reference to FIGS. 1 to 4 corresponding to the embodiments. The manufacturing method of the lining pipe P of the present invention is such that the molten hot melt adhesive G is continuously formed into a film on the outer peripheral surface Wa of the pipe W that is continuously extruded and conveyed at a predetermined speed. after coating, the cooling to solidify the adhesive G, to form the adhesive layer L, to obtain a P for tube lining is cut every predetermined length, the cut, de
While rotating the disc cutter 30, rotate around the pipe body.
The pipe body can be rotated and simultaneously moved toward the center of the pipe body.
Is characterized in Rukoto allowed to push cutter cutting.

Further, in the method for manufacturing a lining pipe body according to the present invention, the pipe body W which is continuously extruded and conveyed at a predetermined speed is continuously inserted into the die 12, and the die 1
The hot melt adhesive G melted in 2 is continuously extruded from the die 17 in the shape of an annular film, the atmospheric pressure inside the mold 12 is lowered, and the adhesive G is continuously applied to the outer peripheral surface Wa of the tubular body W. Then, the adhesive G is cooled and solidified to form an adhesive layer L on the outer peripheral surface Wa of the tubular body W, and then the tubular body W is cut into a predetermined length and lining. After obtaining the pipe body P , the disc cutter 30 is used for the cutting.
While revolving around the pipe, it revolves around the pipe at the same time.
It is characterized in that the tube body is pushed and cut by moving it toward the center of the tube .

Further, the lining pipe manufacturing apparatus 1 of the present invention continuously extrudes the pipe W, and
An extruding section 2 for conveying the tubular body W at a predetermined speed, and a coating for continuously applying the melted hot melt adhesive G to the outer peripheral surface Wa of the tubular body W conveyed by the extruding section 2 in a film form. Part 8, a cooling unit 21 for cooling and solidifying the hot melt adhesive G applied by the applying unit 8, and the tubular body having an adhesive layer L formed on the outer peripheral surface Wa by the cooling unit 21. A cutting unit 27 for cutting W into predetermined lengths, and the units 2, 8, 21, and 27 are arranged in series, and the cutting unit includes a plurality of disc cutters.
30 are arranged at equal intervals around the pipe body, and
When the scatter is controlled to rotate in the same direction,
Both of them rotate around the outer circumference of the pipe in the same direction, and at the same time,
It is characterized in that it is designed to move toward the center of .

The coating part 8 is provided with a die 12 having a die 17 for extruding the molten hot melt adhesive G into a continuous annular film shape, and lowers the air pressure inside the die 12. A suction pump 18 is connected and the adhesive G extruded from the mold 12 is transferred to the tubular body W.
The outer peripheral surface Wa may be applied in close contact.

[0013]

The tube W is continuously extruded by the extruding section 2 and conveyed at a predetermined speed. The tubular body W that is continuously transported is continuously coated with the melted hot melt adhesive G on the outer peripheral surface Wa in a film shape by the coating unit 8. Then, the hot melt adhesive G is cooled and solidified in the cooling unit 21, and the adhesive layer L is formed on the outer peripheral surface Wa of the tubular body W. After that, the pipe body W is cut into predetermined lengths by the cutting unit 27 to form the lining pipe body P.

The adhesive G applied in the applying section 8
Is continuously extruded in the shape of an annular film by the die 17 provided in the die 12 of the coating unit 8, and the air pressure inside the die 12 is lowered by the suction pump 18, so that the outer peripheral surface of the tubular body W is Adhesive G is applied to Wa so as to continuously adhere to Wa.

[0015]

1 is a schematic side view showing an embodiment of an apparatus for manufacturing a lining tube according to the present invention, FIG. 2 is a side sectional view of a coating section constituting the manufacturing apparatus according to the embodiment, and FIG. FIG. 4 is a side sectional view of a cooling unit constituting the manufacturing apparatus according to the embodiment, and FIG. 4 is a schematic front view of a cutting unit constituting the manufacturing apparatus according to the embodiment.

First, the structure of the lining tube manufacturing apparatus 1 of the present invention will be described. This lining pipe P
As shown in FIG. 1, the manufacturing apparatus 1 of 1. is roughly configured by an extrusion unit 2, a coating unit 8, a cooling unit 21, and a cutting unit 27.
Each part is arranged in series.

First, the extruding section 2 comprises an extruder 3, a water tank 5, a printing machine 6 and a take-up machine 7, and the respective parts are arranged in series.

The extruder 3 is supplied with a pellet- or powder-like thermoplastic resin molding material, which is the material of the tubular body W, such as vinyl chloride resin, and heats this resin to soften and melt it, and at the same time, this resin is subjected to an annular die. The tubular body W having a hollow circular cross-sectional shape is continuously formed by extruding from the die 4 configured by.

The water tank 5 is disposed so as to face the mold 4 of the extruder 3, and the tubular body W formed by the extruder 3 is introduced from the entrance of one of the openings formed in the pair of side surfaces. Is entering. Then, in the water tank 5, the formed tubular body W is cooled and solidified by discharging cooling water or the like, and is carried out from the outlet of the other opening.

Next, the printing machine 6 is arranged adjacent to the outlet side of the water tank 5, supports the tube W that is solidified and conveyed by the water tank 5, and supports the outer peripheral surface of the tube W.
This device prints the standard number of the pipe body W, the pipe size, the manufacturing date, and the like.

The take-up machine 7 is adjacent to the printing machine 6 and, after being extruded by the above-mentioned extruder 3, is cooled and solidified in the water tank 5, and the tube W is sandwiched by tracks, rolls, belts, etc. By rotating the tube W, the tube W is always pulled at a constant speed and conveyed to the next step. That is, the tubular body W is continuously molded by the take-up machine 7 together with the extrusion molding of the extruder 3 and simultaneously conveyed at a constant speed. In addition, depending on the take-up speed of the take-up machine 7, the pipe W
Is determined.

Next, the coating section 8 faces the outlet of the take-up machine 7 and is arranged in series with the pushing section 2 as shown in FIG. The coating unit 8 is generally composed of a melt extruder 9 and a mold 12.

First, the melt extruder 9 is supplied with, for example, a powdery hot melt adhesive which is not sticky at room temperature,
This adhesive is heated and melted, and the molten hot-melt adhesive G is continuously extruded to the heat hose 11 connected to the delivery port 10.

Next, as shown in FIG. 2, the die 12 is formed in a rectangular block shape, and a conveying path 13 penetrating the center thereof is bored. The transport path 13 is
It is a through hole having a circular cross section, and is set to an inner diameter slightly larger than the outer diameter of the tubular body W formed by the extruding portion 2 described above. An entrance 13a which is one opening of the transport path 13
Is opposed to the exit of the take-up machine 7 of the extruding section 2 described above, and a disc-shaped seal rubber 14 having a circular opening at the center is arranged at the opening peripheral edge of the entrance 13a.

In addition, the die 12 is provided with the transfer path 13
The flow path 15 is formed in an annular shape around the circumference of. A part of the base end of the flow path 15 is connected to the connection flow path 16 that opens to the outer surface of the mold 12, and the melt extruder 9 described above is connected.
The end of the heat hose 11 provided in is connected,
The molten adhesive G is sent in.

An annular ferrule 17 is formed at the tip of the flow path 15, and is concentrically opened around the exit 13b of the transport path 13. The slits of the die 17 are formed at uniform intervals of 0.6 to 0.8 mm, and the die 17 and the outer peripheral surface Wa of the tubular body W passing through the transfer path 13 of the die 12 are separated from each other. The interval is set to 2 to 5 mm. That is, the film-shaped adhesive G formed in an annular shape is pushed out by the base 17.

Further, the mold 12 has an intake passage 19 connected to a vacuum pump 18 as a suction pump shown in FIG.
Are formed. As shown in FIG. 2, the intake path 19 is open to the inner peripheral surface 13c of the transfer path 13 so as to reduce the air pressure inside the mold 12.

Further, the adjusting bolts 20 are arranged on the die 12 vertically and horizontally so that the slit intervals of the die 17 can be finely adjusted.

Next, the cooling unit 21 is, as shown in FIG.
The water tank 22 and the water discharge port are arranged next to the coating unit 8 and are generally configured. As shown in FIG. 3, the water tank 22 is provided with openings 23 and 24 on both sides, and both openings 23 and 24 are formed in a circular shape having an inner diameter larger than the outer diameter of the tubular body W. The one opening 23 opposes the outlet 13b of the die 12 of the coating unit 8 so that the tubular body W can enter.

As shown in FIG. 3, a water discharge port 25 is provided in the water tank 22, and cooling water is discharged to the pipe body W moving in the water tank 22. In addition, a seal rubber 26 is provided on the periphery of the other opening 24 so that water droplets and the like attached to the outer peripheral surface of the tubular body W can be removed by discharging water.

Next, the cutting section 27, as shown in FIG.
It is arranged adjacent to the cooling unit 21. This cutting part 27
Is composed of a gantry 28 and a cutter mechanism section 29 that slides on the gantry 28.

The cutter mechanism section 29 is composed of a disk cutter mechanism using a plurality of circular rotary teeth (disk cutters). In this embodiment, as shown in FIG. 4, three disk cutters 30 are spaced at 120 ° intervals. The tube bodies W are arranged at the center of each disk cutter 30.

The disk cutters 30 are controlled so as to rotate in the same direction, and rotate around the outer circumference of the pipe W in the same direction, and at the same time move in the center direction of the pipe W. . A slide mechanism (not shown) is provided in the cutter mechanism section 29, and the cutter mechanism section 29 slides on the pedestal 28 in response to the transport movement of the tubular body W.

At the rear of the cutting portion 27, there is arranged a stacker truck 31 for accommodating the cut lining pipe body P as a product.

Next, the manufacturing apparatus 1 configured as described above.
A method of manufacturing the lining pipe P by the method will be described. First, the extruder 3 of the extruding section 2 heats the pellet- or powder-shaped vinyl chloride resin that is the material of the tubular body W, softens and melts it, and extrudes this resin from the die 4 of the annular die to form a hollow circular shape. The tubular body W is continuously molded.

The formed tube W has not been solidified yet at a high temperature, but the tube W is cooled and solidified by entering the water tank 5 through the sizing die and entering the water tank 5 through the sizing die. Be delivered from the exit. The diameter of the tubular body W immediately after being extruded from the extruder 3 is reduced to about 80% by this diameter reducing cooling action.

Next, the tubular body W is conveyed to the printing machine 6 and a standard number, pipe size, manufacturing date, etc. are printed on the outer peripheral surface Wa thereof. Then, the tubular body W is continuously taken at a constant speed by the take-up machine 7, and is conveyed to the next step.

When the tubular body W is conveyed to the coating section 8 by the extruding section 2, it enters the conveying path 13 formed in the die 12 of the coating section 8 and penetrates the conveying path 13. Moving.

At the same time, from the melt extruder 9, for example, a temperature of 15
The hot melt adhesive G heated and melted at 5 ° C. is fed into the flow path 15 in the mold 12 through the heat hose 11 and extruded from the die 17. With this die 17, the melted adhesive G is formed into an annular film shape, and the die 12
Is continuously extruded onto the outer peripheral surface Wa of the tubular body W carried out from the outlet 13b of the conveyance path 13.

At the same time, the vacuum pump 18 is activated,
A space surrounded by the outer peripheral surface Wa of the tubular body W in the mold 12, the inner peripheral surface 13c of the mold transfer path 13, the seal rubber 14 on the entrance 13a side, and the film-like adhesive G on the exit 13b side. Reduce the air pressure inside.

Then, the pipe W is pushed out from the mouthpiece 17 and
G-shaped adhesive G delivered to the outer peripheral surface Wa of the
Is adhered and applied to the outer peripheral surface Wa of the tubular body W to form the adhesive G on the outer peripheral surface Wa of the tubular body W in a layer having a uniform thickness (see FIG. 2). Immediately after the adhesive G is applied to the tubular body W, the adhesive G is still in a molten state at a high temperature.

The tubular body W coated with the adhesive G is further transported and enters the water tank 22 of the cooling unit 21 through one opening 23. Then, in the water tank 22, the pipe W is sprayed with cooling water from the water outlet 25, the adhesive G on the outer periphery is cooled and solidified to form the adhesive layer L.

The adhesive G is solidified by the cooling section 21, and the tubular body W formed in layers is carried out from the other opening 24 of the water tank 22 and conveyed to the cutting section 27. In the cutting section 27,
The cutter mechanism unit 29 operates at the time when the pipes W that are continuously conveyed are conveyed for a predetermined length.

In the cutter mechanism portion 29, the disc cutters 30 rotate in the same direction with respect to the pipe body W at the cutting position, and rotate around the outer periphery of the pipe body W at the same time as the center direction of the pipe body W. Then, the pipe W is cut. That is, the disc cutter 30 rotates while rotating the tubular body W.
By revolving around, and moving toward the center of the pipe W at the same time, the pipe W is pushed and cut.

Since the tubular body W is continuously conveyed at the cutting section 27, the cutter mechanism section 29 causes the tubular body W to move.
The slide movement is performed on the gantry 28 corresponding to the transport movement of the above, and the cutting is performed.

Then, the tubular body W cut into a predetermined length becomes the lining tubular body P and is housed in the stacker truck 31.

Therefore, in the method and apparatus for manufacturing the lining pipe P having the above-described structure, the pipe W is extruded and conveyed, and the hot melt adhesive G is extruded onto the outer peripheral surface Wa thereof. With this configuration, the tube W can be manufactured and the adhesive G can be applied in a series of steps, so that the lining tube P can be easily manufactured.
In addition, since the outer peripheral surface Wa of the tubular body W is a uniform and continuous surface, the thickness of the adhesive G can be made uniform when the adhesive G is applied.

Further, since the die 12 for applying the adhesive G constantly extrudes a stable and fixed amount of the hot melt adhesive G, it is possible to ensure the stability of the application to the outer peripheral surface Wa of the tubular body, and at the same time, the outer peripheral surface Wa The thickness of the adhesive G applied to the surface of the adhesive can be accurately controlled, and the adhesive layer L having a uniform thickness can be obtained.
It is possible to obtain the lining pipe body P in which is formed.

Further, according to the manufacturing apparatus 1 for the lining pipe P, the adhesive G having a uniform thickness is extruded in the form of a film, and the adjusting bolt 20 is provided on the die 12, so that the pipe W is formed. The coating can be performed so that the thickness of the adhesive layer L formed on the outer peripheral surface Wa of the is not uneven.

Further, since the vacuum pump 18 is connected to the mold 12 of the apparatus 1 to reduce the atmospheric pressure in the mold 12,
Since the adhesive G extruded from the mold 12 does not float up and bubbles do not enter between the adhesive G and the outer peripheral surface Wa of the tubular body W, the adhesive layer L is firmly adhered to form the lining. The quality of the pipe body P is improved.

Further, according to this apparatus 1, since it is possible to use the hot-melt adhesive G having a high softening point, the adhesive layer L is applied after being applied to the tube W, cooled and solidified.
The surface of the adhesive does not become sticky, the adhesives do not block during packing, storage, transportation, etc., and there is no problem of adhesion between the pipes P.

Further, when the tubular body W is cut after the application of the adhesive G, when cutting with a saw blade cutter, the cut surface is heated, but the applied adhesive may be melted and deformed. According to the cutting machine 27 of the apparatus 1 of the present invention, since the adhesive G in the vicinity of the cut surface is not deteriorated because it is cut by pressing, the lining pipe P having good quality can be obtained.

[0053]

As described above, in the method and apparatus for manufacturing a lining pipe according to the present invention, the pipe is extruded and conveyed, and the hot melt adhesive is extruded on the outer peripheral surface thereof. Since the parts for performing these steps are arranged in series in addition to the configuration for applying, there is an effect that the production of the pipe body and the application of the adhesive can be performed in a series of steps, and the lining pipe can be easily used. The effect is that you can get a body. From this, since the outer peripheral surface of the tubular body is a uniformly continuous surface, there is an effect that the thickness of the adhesive can be formed evenly and evenly when the adhesive is applied. .

Further, according to this manufacturing apparatus, the mold for applying the adhesive to the pipe body always extrudes a stable and fixed amount of the hot-melt adhesive, so that the stability of the coating on the outer peripheral surface of the pipe body can be ensured. At the same time, there is an effect that the thickness of the adhesive applied to the outer peripheral surface can be accurately controlled, and a lining tube having an adhesive layer with a uniform thickness can be obtained.

Further, since the suction pump is connected to the mold of this apparatus to reduce the air pressure inside the mold, the adhesive pushed out from the mold does not float up from the outer peripheral surface of the pipe, and the adhesive and the pipe are separated from each other. Since the adhesive layer is formed in close contact with no air bubbles between the outer peripheral surface and the outer peripheral surface, there is an effect that the quality of the lining pipe body is improved.

Further, according to this apparatus, since it is possible to use a hot-melt adhesive having a high softening point, the surface of the adhesive layer does not become sticky after it is applied to the pipe and cooled and solidified. It has the effect that dust etc. will not adhere to its surface, and further, packing and storage of this lining pipe body,
In the case of transportation, there is an effect that the adhesive layers on the surface do not block, and problems such as adhesion between the tubular bodies do not occur.

[Brief description of drawings]

FIG. 1 is a schematic side view showing an embodiment of an apparatus for manufacturing a lining pipe body according to the present invention.

FIG. 2 is a side sectional view of a coating section which constitutes the manufacturing apparatus according to the embodiment.

FIG. 3 is a side sectional view of a cooling unit which constitutes the manufacturing apparatus according to the embodiment.

FIG. 4 is a schematic front view of a cutting unit that constitutes the manufacturing apparatus according to the embodiment.

[Explanation of symbols]

1. Manufacturing equipment 2 ... Extrusion section 8 ... Coating section 12 ... Mold 17 ... 18 ... Suction pump (vacuum pump) 21 ... Cooling unit 27 ... Cutting part G: Hot melt adhesive L ... Adhesive layer P ... Lining tube W ... Tube Wa ... Outer peripheral surface

Continuation of the front page (56) Reference JP-A-4-272822 (JP, A) JP-A-57-6740 (JP, A) JP-A-5-329432 (JP, A) Kenkichi Murakami, Extrusion, Japan, Stocks Plastics Age / Eiichi Asayama, Dec. 10, 1985, 271-272 (58) Fields investigated (Int.Cl. ⁷ , DB name) B29C 47/00-47/96 B29C 63/00 -63/48 B05C 5/00-5/04 B05D 7/00-7/26

Claims (4)

(57) [Claims] 1. A molten hot-melt adhesive is continuously applied in the form of a film on the outer peripheral surface of a tubular body which is continuously extruded and conveyed at a predetermined speed, and then the adhesive is cooled. Is solidified to form an adhesive layer, which is cut at a predetermined length to obtain a lining tube.
While revolving the cutter, it revolves around the pipe and simultaneously
The pipe body by pushing it toward the center of the pipe body.
Method of manufacturing a lining pipe body, wherein Rukoto to cross. 2. A tube body which is continuously extruded and conveyed at a predetermined speed is continuously inserted into a mold, and hot melt adhesive melted in the mold is continuously formed into a ring-shaped film shape from a die. Then, the pressure inside the mold is lowered, and the adhesive is continuously adhered to the outer peripheral surface of the pipe to apply the adhesive, and then the adhesive is cooled and solidified to the outer peripheral surface of the pipe. the adhesive layer was formed, to obtain a lining pipe body and then cutting the tube body at predetermined lengths, said cutting, di
Revolve around the pipe while rotating the scutter.
At the same time, push the pipe body by moving it toward the center of the pipe body at the same time.
Method of manufacturing a lining pipe body, wherein Rukoto is cut cut. 3. A tubular body is continuously extruded, and
An extruding section for conveying the tubular body at a predetermined speed, an applying section for continuously applying a melted hot melt adhesive to the outer peripheral surface of the tubular body conveyed by the extruding section in a film form, and the applying section A cooling unit that cools and solidifies the hot melt adhesive applied by, and a cutting unit that cuts the tubular body having an adhesive layer formed on the outer peripheral surface by the cooling unit at predetermined lengths, And each of the parts is arranged in series, and the cutting part includes a plurality of disc cutters.
Centered around the body, the disc cutters are evenly spaced.
The tubes are controlled so that they rotate in the same direction.
Rotate the outer circumference in the same direction, and at the same time
An apparatus for manufacturing a lining pipe body, which is adapted to move . 4. The applying section is provided with a die having a die for pushing out the melted hot melt adhesive into a continuous annular film shape, and is connected with a suction pump for lowering the air pressure inside the die. The lining pipe manufacturing apparatus according to claim 3, wherein the adhesive extruded from the mold is applied in close contact with the outer peripheral surface of the pipe.