JP4028726B2 - Melt forming method for interior pipes in pipelines - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a melt molding method for interior pipes in pipes such as gas pipes, communication pipes, power pipes, and water and sewage pipes, and more particularly to existing pipes such as aged cast iron pipes, steel pipes and concrete pipes. It is applied to the renewal of existing pipes by melt-molding interior pipes made of polyethylene resin having durability in the pipe lines, and in particular, the efficiency of construction work in elongated pipe lines and the strengthening of pipe lines The present invention relates to a melt molding method for an interior pipe in a pipe line capable of achieving the above.
[0002]
[Prior art]
Conventionally, as the main lining method for pipelines applied to rehabilitation and repair of this kind of old existing pipes, the lining method by airflow, the lining method by pig, the lining method by resin plug, etc. are known. However, since the lining material is lined by moving the liquid lining material, the lining layer is relatively thin, and the liquid lining material is supplied to the deep lining portion of the pipe. Or there is also an inconvenience that it is difficult to handle the lining construction such as feeding an appropriate amount.
[0003]
On the other hand, Japanese Patent Laid-Open No. 63-295237 discloses a method for lining a pipe without moving a solid lining material.
This pipe lining method is a method of pressing a synthetic resin on the inner surface of a pipeline by pressing the inner side of the pipeline while heating and softening a lining material made of a long strip of synthetic resin inserted into the pipeline. In this lining method, as shown in FIG. 5, a lining material made of a long strip of synthetic resin is formed into a spiral tube b having the same diameter as the conduit a, and the spiral tube b is formed. A process of inserting the entire length of the pipe line a from the start pipe port of the pipe line a to be lined while being rotated, and moving into the start end part of the spiral pipe b inserted into the pipe line a. A heating pig c equipped with an electric heater c ′ is installed, a step of applying a lid d to the starting end of the spiral tube b, and the inside of the spiral tube b between the lid d and the heating pig c is supplied by a conduit e. In-pipe movement of heating pig c while maintaining the pressurized state with pressurized air The inner surface lining method for the pipe line a is composed of a step of forming an inner surface lining composed of the smooth tube b ′ by pressing the spiral tube b in the radial direction of the tube while heating and softening.
[0004]
[Problems to be solved by the invention]
However, in the inner surface lining method of the pipe a in the prior art, the lining material made of a long strip is lined with the lining material made of a synthetic resin long strip on the inner surface of the pipe a. From a lining material made of a long strip, it must be formed into a helical tube b having the same diameter as a, and is inserted over the entire length of the conduit a while rotating the helical tube b. It takes time and effort to form the helical tube b having the same diameter as the pipe a and to insert the helical tube b, which is a lining material, into the pipe a, and the pipe a to be lined is elongated. This is conspicuous in the case of the road a, and there is a disadvantage that the work efficiency of the lining construction is lowered.
[0005]
Further, when the synthetic resin spiral tube b is lined on the inner surface of the conduit a, the synthetic resin spiral tube b is heated and molded in the same process, that is, simultaneously by only the heating pig c moving in the tube. Therefore, a difference occurs in the progress of heating and melting by the heating pig c between the inner surface side and the outer surface side of the synthetic resin spiral tube b, and as shown in FIG. 6, the inner surface side of the synthetic resin spiral tube b is heated and softened. The outer surface side of the synthetic resin spiral tube b can maintain its original shape due to insufficient progress of heat softening, and as a result, the lining layer has a helical thin wall on the layer itself. Since the portion is formed and separated from the inner surface of the pipe a, there is a disadvantage that the strength of the lining layer is reduced.
[0006]
An object of the present invention is to solve the above-described problems in the prior art, and to provide a melt molding method for an interior pipe in a pipe that can improve the efficiency of construction work and strengthen the pipe. It is what.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is a method of melt-molding an interior pipe made of polyethylene resin on the inner surface of a pipe, and includes a tubular interior material made of polyethylene resin inserted into the pipe, and a heater A concentric heating path is formed between the inner cylinder and the outer cylinder each having a built-in portion around the entire circumference by a support plate provided radially in the rear region between the inner cylinder and the outer cylinder . And a heating cylinder supported by the support means on the inner surface of the pipe line and pulled by the traction means to move in the pipe line, and a diameter-enlarged molded cylinder extending at the rear end of the inner cylinder in the heating cylinder. An interior material melting process in which the interior material is heated by moving the heating cylinder through which the interior material is inserted into the heating path and sequentially melted, and the melted interior material is subjected to diameter expansion molding by moving the molding cylinder to the pipe inner surface. Sequentially molding interior pipes made of polyethylene resin It is intended to include the interior pipe forming process.
[0008]
According to this feature , the tubular interior material made of polyethylene resin inserted into the heating path of the heating cylinder is sequentially melted by the heating cylinder that is pulled by the traction means and moves in the duct, and the interior material is sequentially melted. Since the inner pipe can be sequentially formed on the inner surface of the pipe line continuously with the following expanded diameter forming cylinder, the inner material can be used in the tubular form and the efficiency of the construction work can be improved. Can be planned.
[0009]
The heating cylinder has a built-in heater over the entire circumference of the inner cylinder and the outer cylinder, and the heating path provided around the heating cylinder is uniformly heated by the heater, so that it is inserted into the pipe. The tubular interior material can be uniformly melted by the heating path, and since the heating path is heated from the inner peripheral side and the outer peripheral side by the heater, the heating density can be increased, so the heating cylinder is shortened. Therefore, the device can be made compact.
[0010]
Furthermore, since the interior material that has been sequentially melted by the heating cylinder is subjected to the diameter expansion molding to the interior pipe in succession by the diameter-expanded molding cylinder, the thickness of the interior pipe formed on the inner surface of the pipe line is Since it is determined by the wall thickness of the tubular interior material and the uniform expansion ratio of the molded cylinder, the thickness of the tubular interior material is selected according to the target wall thickness of the interior pipe, and the target of the interior pipe It can be formed thick, and the pipe line can be strengthened. The heating cylinder and the molding cylinder are both configured so that the inside can be ventilated, so that the molding cylinder is blown from the molding cylinder side. Can be efficiently cooled, and the inner tube can be stably molded.
[0011]
Furthermore, existing pipes that were reinforced by the target wall thickness in the interior material melting process and the subsequent interior pipe molding process were made of polyethylene resin, which caused existing pipes to corrode and disappear. However, the required performance as, for example, a city gas pipe can be maintained only by the interior pipe.
[0013]
In addition, since the heating path is formed by a support plate provided radially between the inner cylinder and the outer cylinder, the heating path can be formed concentrically between the inner cylinder and the outer cylinder. Since the support plate is provided in the rear area of the heating path, the support plate is always located in the melting region of the interior material, so that the support plate can move the heating cylinder without interfering with the movement of the heating cylinder. The material can be heated and melted sequentially.
[0014]
According to the present invention, in addition to the above-described features, at least one of the support plates has a lead wire passage for the heater and the temperature sensor of the outer cylinder formed therein, and the lead wire of the outer cylinder. The passage is in communication with a lead wire passage formed in the inner cylinder.
[0015]
According to this feature , since the lead wire passage is formed in the support plate and communicates with the lead wire passage formed in the inner cylinder, the lead wires for the heater of the outer cylinder and the temperature sensor are internally provided. Wiring can be performed without exposure to the melting region of the material.
[0016]
Further, according to the present invention, a plurality of cooling fins are erected on the inner peripheral surface of the cylinder main body in the molded cylinder in addition to the above-described features .
[0017]
Further , according to the present invention, since the forming cylinder is uniformly cooled by the cooling fins, the melted interior material can be formed into a stable interior pipe having a uniform predetermined thickness by the forming cylinder.
[0018]
Further, according to the present invention, in addition to the above-described features , the support means is configured by a plurality of support legs that abut on the inner surface of the pipe line provided in the peripheral region between the front end portion and the rear end portion of the outer cylinder in the heating cylinder. It is what has been.
[0019]
According to this feature , as the support means for the heating cylinder, the plurality of support legs that contact the inner surface of the pipe line are provided in the peripheral area of the front end portion and the rear end portion of the outer cylinder. It is supported concentrically with respect to the inner surface of the pipe, and an inner pipe having a uniform thickness can be formed by the forming cylinder.
[0020]
According to the present invention, the traction means moves the heating cylinder and the forming cylinder by pulling the front end side of the heating cylinder with the towing rope in combination with the above-described features .
[0021]
Further , according to the present invention, even if a trouble occurs during the molding operation of the interior pipe, the heating cylinder is connected to the heating cylinder, so that the heating cylinder and the molding cylinder integral with the heating cylinder are left in the pipeline. You can work safely without having to.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described with reference to an embodiment shown in the drawings. FIG. 1 is a longitudinal side view of a melt molding method for an interior pipe in the pipe of the present invention, and is an explanatory view showing the entire melt molding method for the interior pipe, and FIG. 2 is a longitudinal section of the line AA in FIG. FIG. 3 is a front elevational view taken along the line BB in FIG. 1, and FIG. 4 is a longitudinal front view taken along the line CC in FIG.
[0023]
The present invention is a method of forming an interior pipe 22 while sequentially melting a tubular interior material 2 made of a heat-meltable polyethylene resin on the inner surface of a pipeline 1 of an aging existing pipe, A concentric heating path 33 is formed between the tubular interior material 2 made of polyethylene resin and the inner cylinder 31 and the outer cylinder 32 each containing the heater 34 over the entire circumference. The heating cylinder 3 supported by the support means on the inner surface of the pipe line 1 and pulled by the pulling means to move in the pipe line 1, and the diameter-expanded shape extending to the rear end of the inner cylinder 31 in the heating cylinder 3. An interior material melting step in which the interior material 2 is heated and melted sequentially by movement of the heating cylinder 3 having the interior material 2 inserted through the heating path 33, and the melted interior material 21 is The diameter of the pipe is increased by movement, and the inner surface of the pipe 1 is made of polyethylene resin The internal tube forming step of sequentially forming the internal tube 22 is described. First, the configuration of the internal tube forming mechanism used in the melt forming method of the internal tube 22 in the pipe line 1 of the present invention will be described with reference to FIGS. A description will be given based on FIG. 1 with reference to FIG.
[0024]
The main structure of the inner tube forming mechanism is composed of a heating cylinder 3 and a forming cylinder 4 provided integrally on the rear end side of the heating cylinder 3, and is provided in a peripheral region between the front end portion and the rear end portion of the heating cylinder 3. Are provided with a plurality of support legs 5 as support means for abutting the inner surface of the pipe 1, and the tip portions of a plurality of traction rods 6 integrally provided on the tip side of the heating cylinder 3 are attached to the tow rope 61. The heating cylinder 3 and the forming cylinder 4 are connected to move inside the pipe line 1 by a driving means (not shown).
[0025]
The heating cylinder 3 includes an inner cylinder 31 and an outer cylinder 32 each containing a heater 34 over the entire circumference, and a plurality of radial lines are provided between the inner cylinder 31 and the outer cylinder 32 in the rear region. A heating path 33 concentric with the inner cylinder 31 and the outer cylinder 32 is formed by the support plate 35, and a lead for the heater and the temperature sensor of the outer cylinder 32 is provided in one of the support plates 35. A wire passage 36 is formed, and the lead wire passage 36 of the outer cylinder 32 is in communication with a lead wire passage 37 formed in the inner cylinder 31, and leads for heaters and temperature sensors of the outer cylinder 32. The wire 38 is inserted through the lead wire passages 36 and 37 and wired to the rear of the pipe 1 together with the heater lead wire 38 and the temperature sensor lead wire 38 and is connected to a power source and a temperature controller (not shown). .
[0026]
The forming cylinder 4 is extended in diameter at the rear end of the inner cylinder 31 in the heating cylinder 3, and the outer peripheral surface on the front peripheral side of the forming cylinder 4 is flush with the small diameter surface of the heating path 33 of the heating cylinder 3. In addition, a tapered surface is formed so as to guide the melted interior material 21, a fluororesin coating layer 42 is formed on the surface of the tube body, and a plurality of cooling fins are formed on the inner peripheral surface of the tube body. 41 is erected in the pipe direction, and the outer peripheral surface of the forming cylinder 4 is set so that the inner pipe 22 having a target thickness can be formed with respect to the inner peripheral surface of the pipe 1. .
[0027]
In addition, the outer peripheral surface of the outer cylinder 32 in the heating cylinder 3 is formed to have a smaller diameter than the inner peripheral surface of the pipe line 1, and the inner surface of the pipe line 1 is provided in the peripheral region between the front end portion and the rear end part of the outer cylinder 32. A plurality of support legs 5 that are in contact with each other are urged outward by spring means (not shown), and the heating cylinder 3 and the molded cylinder 4 are concentric with the inner peripheral surface of the pipe line 1 by the plurality of support legs 5. In addition, the leading ends of a plurality of traction rods 6 integrally provided on the distal end side of the heating cylinder 3 are connected to the towing rope 61, and the heating cylinder 3 and the molded cylinder 4 integral therewith Is moved in the pipe 1 by driving means (not shown).
[0028]
The internal pipe forming mechanism used for the melt forming method of the internal pipe 22 in the pipe line 1 of the present invention is configured as described above. Next, the internal pipe 22 in the pipe line 1 using this internal pipe forming mechanism is configured. The melt molding method will be described with reference to FIG.
[0029]
In the melt molding of the inner pipe 22 in the pipe 1, first, as a preliminary process, a tubular inner material 2 made of a heat-meltable polyethylene resin is inserted over the entire length of the pipe 1. 2 may be, for example, a vinyl chloride tube, a polybutene tube, or a polyamide tube. What is important when inserting the interior material 2 into the conduit 1 is that the thickness of the interior material 2 made of polyethylene resin is cut off. The interior material 2 whose area corresponds to the cross-sectional area of the target thickness of the interior pipe 22 that is melt-formed on the inner surface of the pipe line 1 is selected, whereby the interior material 2 is sequentially melted and melted. Continuous melt molding in which the interior material 21 is sequentially molded on the inner peripheral surface of the pipe line 1 as the interior pipe 22 becomes possible.
[0030]
In FIG. 1, the tubular interior material 2 made of polyethylene resin inserted over the entire length of the pipe 1 does not move in the direction of the pipe 1, whereas the heating cylinder 3 and the molding cylinder 4 are Since the tow rope 61 connected to the tip of the tow bar 6 is moved through the inside of the pipe line 1 by a driving means (not shown), the polyethylene inserted over the entire length in the pipe line 1 The tubular interior material 2 made of resin is first heated by the heating path 33 formed in the heating cylinder 3 in which the heater 34 is built, and the interior material 2 is moved by the movement of the heating cylinder 3, that is, the movement of the heating path 33. It is melted on the rear side of the heating path 33.
[0031]
Next, the interior material 21 melted on the rear side of the heating path 33 is cooled and molded by the molding cylinder 4 in which a plurality of cooling fins 41 are erected on the inner peripheral surface in the pipe line direction. The interior material 21 melted by the movement can form an interior tube 22 having a target thickness with respect to the inner peripheral surface of the pipe line 1. The forming cylinder 4 has a front peripheral edge connected to a rear peripheral edge of the inner cylinder 31 of the heating cylinder 3, and an outer peripheral surface on the front peripheral side of the forming cylinder 4 has a small diameter surface and a surface of the heating path 33 of the heating cylinder 3. The inner diameter of the pipe line 1 is formed by guiding the melted interior material 21 by the tapered surface of the forming cylinder 4 so as to guide the melted interior material 21. The inner tube 22 can be smoothly formed on the surface.
[0032]
In addition, since the heating cylinder 3 and the molding cylinder 4 are both configured such that the inside side can be ventilated, the molding cylinder 4 can be efficiently cooled by blowing air from the molding cylinder 4 side, and the inner tube 22 is stabilized. Can be molded.
[0033]
Further, the heating cylinder 3 and the molding cylinder 4 integrated with the heating cylinder 3 are provided by a plurality of support legs 5 that come into contact with the inner surface of the pipe line 1 provided in the peripheral area between the front end portion and the rear end portion of the outer cylinder 32 in the heating cylinder 3. The heating path 33 of the heating cylinder 3 is concentrically supported with respect to the inner peripheral surface of the pipe 1, and is concentric with the inner cylinder 31 and the outer cylinder 32 by a plurality of support plates 35 provided radially. Therefore, the uniform inner tube 22 can be formed on the inner surface of the pipe 1 by supporting the heating cylinder 3 and the forming cylinder 4 at regular intervals with respect to the inner peripheral surface of the pipe 1. .
[0034]
【The invention's effect】
The present invention is configured as described above, and the tubular interior material made of polyethylene resin inserted into the heating path of the heating cylinder is sequentially melted by the heating cylinder that is pulled by the traction means and moves in the pipe path, Since the interior material that has been sequentially melted can be successively formed on the inner surface of the pipe line continuously in the subsequent diameter-shaped molding cylinder, the interior material can be used in a tubular form, The efficiency of construction work can be improved.
[0035]
Further, since the interior material sequentially melted by the heating cylinder is subjected to diameter expansion molding on the interior pipe in succession by the expanded diameter molding cylinder, the thickness of the interior pipe molded on the inner surface of the pipe line is Since it is determined by the thickness of the tubular interior material made of polyethylene resin and the uniform expansion rate of the molded cylinder, the thickness of the tubular interior material made of polyethylene resin is selected according to the target thickness of the interior pipe By doing so, the interior pipe can be formed to a target thickness, and the pipe line can be strengthened.
[0036]
Furthermore, because the interior pipe reinforced by the target wall thickness in the interior material melting process and the interior pipe molding process that follows is composed of polyethylene resin, the existing pipe may corrode and disappear. However, the required performance as, for example, a city gas pipe can be maintained only by the interior pipe.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a longitudinal side view of an interior pipe melt molding method in a pipe line according to an embodiment of the present invention, and is an explanatory view showing the entire interior pipe melt molding method.
2 is a longitudinal front view taken along line AA in FIG. 1 and is an explanatory diagram showing an enlarged main part. FIG.
3 is a longitudinal sectional front view taken along line BB in FIG. 1, and is an explanatory diagram showing an enlarged main part. FIG.
4 is a longitudinal front view taken along the line CC in FIG. 1, and is an explanatory diagram showing an enlarged main part. FIG.
FIG. 5 is an explanatory view showing a state in which a smooth pipe is lined on the inner surface of a pipe line by a conventional lining method.
FIG. 6 is an enlarged explanatory view showing a pipe line in which a smooth pipe is lined on the inner surface by a conventional lining method.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pipe line 2 Interior material 21 Melted interior material 22 Interior pipe 3 Heating cylinder 31 Inner cylinder 32 Outer cylinder 33 Heating path 34 Heater 35 Support plate 36 Lead wire path 37 of outer cylinder Lead line path drilled in inner cylinder 38 Lead wire 4 Molded cylinder 41 Cooling fin 5 Support leg 6 as supporting means Towing rod 61 as towing means Towing rope

Claims (5)

A method of melt-molding an inner pipe made of polyethylene resin on the inner surface of a pipe,
A tubular interior material made of polyethylene resin inserted in the pipeline,
A concentric heating path is formed between the inner cylinder and the outer cylinder each containing the heater over the entire circumference by a support plate provided radially in the rear region between the inner cylinder and the outer cylinder. And a heating cylinder that is supported on the inner surface of the pipeline by the support means and that is pulled by the traction means and moves in the pipeline;
A diameter-increased shaped cylinder extending at the rear end of the inner cylinder in the heating cylinder,
An interior material melting step in which the interior material is heated and melted sequentially by movement of a heating cylinder inserted through the heating path through the interior material;
An inner pipe forming step for forming an inner pipe made of a polyethylene resin on the inner surface of the pipe by sequentially expanding the diameter of the melted inner material by moving a forming cylinder and melting the inner pipe. Construction method.   At least one of the support plates is formed therein with lead wire passages for the heater and temperature sensor of the outer cylinder, and the lead wire passage of the outer cylinder is a lead wire passage formed in the inner cylinder. The melt molding method for an interior pipe in a pipe line according to claim 1, wherein   2. The melt forming method for an interior pipe in a pipe line according to claim 1, wherein a plurality of cooling fins are erected on the inner peripheral surface of the cylinder main body.   The said support means is comprised by the some support leg respectively contact | abutted to the pipe inner surface provided in the surrounding area of the front-end part and rear-end part of the outer cylinder in a heating cylinder. A melt molding method for interior pipes in the described pipelines.   The said pulling means pulls the front-end part side of a heating cylinder with a tow rope, and moves a heating cylinder and a shaping | molding cylinder, The melt-forming method of the interior pipe in the pipe line described in Claim 1 characterized by the above-mentioned.

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