JP6734892B2 - Resin processed pipe and method for manufacturing the same - Google Patents

Description

The present invention relates to a resin processed pipe used as a water supply/drainage pipe of a building such as a building or a condominium, and a manufacturing method thereof.

BACKGROUND ART Conventionally, in buildings such as buildings and condominiums, in addition to drainage pipes for water supply and sewerage, many water supply pipes such as water for fire extinguishing, miscellaneous water, and water supply pipes for cooling water are installed. These water supply pipes are configured by selecting a plurality of types of processed pipes according to the installation location and use and connecting them appropriately on site. The processed pipes are connected to each other by a jointing method such as a screwing type, a welding type, a flange type, or a housing type pipe joint.

This housing type pipe joint is made by welding an outer ring made of iron or stainless steel to the outside of the end of a metal processing pipe made of steel pipe or stainless steel pipe, and sealing between the butt ends of each pipe. After sandwiching the rubber ring, attach a pair of upper and lower iron housings around it to cover the rubber ring, and use this iron housing to bridge between the outer rings for preventing the two pipe ends from coming off. It is configured such that a pair of iron housings are annularly connected by bolts.

In addition, as shown in Patent Documents 1 to 3 below, instead of an outer ring for preventing slip-out which is made of iron or stainless steel and is welded to the outside of the end of the metal working pipe, an annular groove is formed at that position. There is also used a method in which the pipes are formed along the circumferential direction, and the processed pipes are connected to each other by fitting the peripheral edge of the iron housing between the grooves.

Meanwhile, the conventional processing tube as described above, therefore mostly is made of a metal such as steel or stainless steel, or proceed corrosion by rust by aging, damaged by joining stress strong like earthquakes I may end up doing it. Further, since metal has high thermal conductivity, when flowing hot and cold water, a cover for heat insulation or heat retention must be provided around it in order to prevent condensation and heat dissipation, resulting in high cost. Furthermore, since it is made of metal, it is heavy, and the transportation and installation work becomes a heavy labor.

On the other hand, processed pipes made of plastic such as polyethylene are superior in corrosion resistance, earthquake resistance and heat insulation compared to those made of metal and are lightweight, so they will be mainly used in buried or pit pipes in the future. In addition, it seems that it will gradually replace the conventional metal processing tube.

JP, 2000-234684, A JP, 2013-210043, A Utility model registration No. 3208106

By the way, in the case where the above-mentioned plastic processing pipes are connected to each other by the conventional housing type pipe joint, when the groove is formed around the pipe end portion as in the above Patent Documents 1 to 3, the wall thickness of the portion is reduced. There is a possibility that it becomes thinner and the strength decreases. On the other hand, as described above, in the method in which the outer ring made of metal or resin is attached around the outside of the pipe end, the connecting ring must be firmly fixed to the pipe end, but the work is extremely difficult. ..

Therefore, the present invention has been devised to solve these problems, and an object thereof is to provide a novel resin-processed pipe having a strong outer ring at the pipe end and a method for manufacturing the same. It is a thing.

A first invention for solving the above-mentioned problems is a processed pipe for piping that is connected by a housing-type pipe joint, wherein the pipe body is provided outside the opening end of a resin pipe body at a distance of 10 to 30 mm. It is a processing pipe made of resin, which is integrally provided with an annular outer ring made of the same resin. With such a configuration, the outer ring is formed of the same resin as the tubular body and is integral with the tubular body, so that the housing-type pipe joint can be firmly engaged. Here, the position of the annular outer ring is set to 10 to 30 mm from the opening end of the pipe body, because when it is less than 10 mm, stress is concentrated on the opening end of the pipe body when connecting by a housing type joint. On the contrary, if it exceeds 30 mm, a large housing type joint is required and it becomes difficult to cope with the existing housing type joint.

A second aspect of the present invention is the resin pipe according to the first aspect, wherein an annular inner ring made of the same resin as the tubular body is integrally provided on the inner peripheral side of the annular outer ring. It is a processing pipe. By providing the inner ring integrated with the tubular body inside the outer ring in this way, it is possible to reinforce the root portion of the outer ring that is subjected to stress when being pipe-joined.

3rd invention is a manufacturing method of 1st invention, Comprising: The pipe body holding|maintenance process which hold|maintains a pair of resin pipe bodies with substantially the same wall thickness and nominal diameter so that the open ends may oppose, Using a pair of outer ring manufacturing molds provided with an annular groove on the inner peripheral side of the opening end of the mold body, and covering the periphery of each pipe body held in the pipe body holding step. A mold mounting step for mounting the pair of outer ring manufacturing molds, an opening end softening step for heating and melting and softening the opening end of each of the held tubular bodies, and a softening step for softening in the opening end softening step And a tube body connecting step of connecting the open ends of the tube body to each other by abutting, and forming an annular outer ring on the outside of the connecting portion by the pair of outer ring manufacturing dies. Is a method for manufacturing a processed pipe for piping. According to such a manufacturing method, it is possible to easily manufacture a new resin processed pipe having a strong outer ring at the pipe end.

4th invention WHEREIN: In the 3rd invention, the bead removal process of cutting/removing the bead inside the said connection part produced at the said pipe connection process is further included, The processing pipe for resin piping characterized by the above-mentioned. It is a manufacturing method. According to such a manufacturing method, it is possible to reinforce the root portion of the outer ring to which stress is applied when the pipe and the joint are joined, and to manufacture a resin-processed pipe in which the internal resistance of the fluid flowing in the pipe is small. can do.

5th invention is a manufacturing method of the processing pipe for piping made from resin, wherein said resin is polyethylene in 2nd or 3rd invention. By using polyethylene as the resin forming the tubular body and the outer ring in this way, it is possible to demonstrate sufficient strength and corrosion resistance as a water pipe, and also to have thermoplasticity and heat welding properties, so it is easy to manufacture. You can

According to the present invention, since the outer ring is made of the same resin as the tubular body and integrated with the tubular body, the housing type pipe joint can be firmly engaged. Further, by providing the inner ring integrated with the tubular body inside the outer ring, it is possible to reinforce the root portion of the outer ring that is stressed when the pipe joint is made.

It is a perspective view showing an embodiment of a processing pipe 100 made of resin according to the present invention. It is a longitudinal cross-sectional view showing an embodiment of a processed pipe 100 made of resin according to the present invention. It is sectional drawing which shows the example of the pipe joint structure by the conventional housing type pipe joint 200. It is a flowchart figure which shows the flow of the manufacturing method which concerns on this invention. It is explanatory drawing which shows the manufacturing method which concerns on this invention. It is explanatory drawing which shows the manufacturing method which concerns on this invention. FIG. 3 is a perspective view showing an example of an outer ring manufacturing die 400 used in the manufacturing method according to the present invention. It is a longitudinal cross-sectional view showing an example of an outer ring manufacturing die 400 used in the manufacturing method according to the present invention. It is explanatory drawing which shows the manufacturing method which concerns on this invention. It is explanatory drawing which shows the manufacturing method which concerns on this invention.

Next, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 and FIG. 2 show an embodiment of a processed pipe 100 made of resin according to the present invention. This processing pipe 100 is used by being appropriately connected to a plurality of pipes depending on the pipe location and distance and used as a water supply/drainage pipe of a building such as a building or a condominium, and an outer ring 20 for connection is integrated with the open end of the pipe body 10. And the inner ring 30 is integrally provided on the inner peripheral side of the outer ring 20.

The tubular body 10 is made of a thermoplastic synthetic resin such as polyethylene (PE), and its length, diameter (nominal diameter), wall thickness, etc. vary depending on the piping location and distance. -5000 mm, nominal diameter 20A-300A, and wall thickness 3-34mm are often used.

The outer ring 20 is an annular protrusion made of the same resin as the tubular body 10 on the outer side of the pipe 10 to 30 mm from the open end of the tubular body 10, and the tubular body 10 is formed by a housing type pipe joint 200 as shown in FIG. It is used when connecting each other. The width and height of the outer ring 20 are not particularly limited, but are, for example, about 5 to 15 mm in width and 5 to 20 mm in height. FIG. 3 shows a connection structure by a conventional housing type pipe joint 200, in which 210 is an arcuate housing member and 220 is a seal member.

On the other hand, the inner ring 30 is formed on the inner side of the tubular body 10 in which the outer ring 20 is formed and at the same position as the outer ring 20 by an annular projection made of the same resin as the tubular body 10. However, the height of the inner ring 30 is significantly lower than that of the outer ring 20, and is, for example, about 1 to 3 mm.

In order to connect the processing pipes 100 according to the present invention having such a configuration, as shown in FIG. 3, the opening ends thereof are butted, and the seal member 220 is provided around the butted portion, A pair of arc-shaped housing members 210, 210 are attached so as to cover the seal member 220. As shown in the figure, since a pair of fitting grooves 211 and 211 extending along the circumferential direction are provided on both sides of the inner surfaces of the housing members 210 and 210, the fitting grooves 211 and 211 are respectively fitted to the fitting grooves 211 and 211. After fitting the outer rings 20, 20 of the processing tubes 100, 100, by connecting both ends of these housing members 210, 210 with bolts (not shown) or the like, the processing tubes 100, 100 do not fall out, Can be firmly connected.

Next, FIGS. 4 to 10 show an embodiment of a method of manufacturing the processed pipe 100 of the present invention having such a configuration. In order to manufacture the processed pipe 100 of the present invention, first, as shown in FIG. 4, a pair of polyethylene pipes made of the same material and having the same size are prepared (step S100). Conventional polyethylene pipes vary in size depending on the piping location and purpose of use, but here at least the same size (nominal diameter, wall thickness) is prepared. Next, the open end faces of the pair of polyethylene pipes on the connection side are chamfered, and set on the clamp 320 so that the open ends face each other (steps S102 and S104).

Specifically, as shown in FIG. 5, these operations are performed using an existing (conventional) butt fusion machine 300. The bat fusion machine 300 includes a frame 310, a pair of clamps 320 and 320 that slide along the frame 310, and a telescopic cylinder 330 that slides the clamps 320 and 320 so that they can move toward and away from each other. The chamfering machine 340 and the heat plate 350 are used, and those conventionally used for fusion-bonding polyethylene pipes in a factory or a work site can be used as they are.

That is, first, as shown in FIG. 5(A), a pair of polyethylene pipes 110 and 110 are attached to the clamps 320 and 320 of the butt fusion machine 300, respectively, so that their open ends are coaxially opposed to each other. Hold. Next, as shown in FIG. 5(B), the chamfering machine 340 is positioned between the polyethylene pipes 110, 110, and the opening end surfaces of the polyethylene pipes 110, 110 are brought into contact with the chamfering machine 340 to open the openings. Chamfer so that the end faces are smooth. The work up to this point is almost the same as the case of manufacturing the polyethylene pipe 110 by the butt fusion machine 300.

Next, if the opening end faces of the polyethylene pipes 110, 110 are chamfered in this way, as shown in FIG. 5C, a pair of outer rings are formed on the opening end sides of the polyethylene pipes 110, 110. The metal molds 400, 400 are attached (step S106). As shown in FIGS. 7 and 8, this outer ring manufacturing die 400 is composed of a cylindrical die body 413 whose both ends are open, and is one open end 410 of the die body 413. An annular groove 411 is formed on the inner edge side along the circumferential direction.

The inner ring of the outer ring manufacturing die 400 has a diameter that is substantially the same as or slightly larger than the outer diameter (nominal diameter) of the polyethylene pipe 110, so that the outer ring is fitted to the outside of the polyethylene pipe 110 with almost no gap. It has become. Further, the length of the outer ring manufacturing die 400 is shorter than that of the portion of the polyethylene pipe 110 protruding from the clamp 320 to the opposite side, as shown in FIGS. 5(C) and 9(A). In a state where the outer ring manufacturing die 400 is in contact with the clamp 320, the open end of the polyethylene pipe 110 projects from the tip thereof by several mm to several tens of mm.

Further, when the outer ring manufacturing dies 400, 400 are attached to the respective polyethylene pipes 110, 110 in this manner, as shown in FIG. Align and install so that they face each other. Although the annular groove 411 is formed on one side of the outer ring manufacturing die 400 in the present embodiment, it may be formed on both sides, in which case the alignment of the groove 411 can be omitted.

Next, after the outer ring manufacturing dies 400 and 400 are attached to the polyethylene pipes 110 and 110 in this way, the respective end faces are cleaned with an organic solvent such as acetone, and then shown in FIG. As described above, the planar heat plate 350 is sandwiched between the abutting end faces of the polyethylene tubes 110, 110, and the end faces are simultaneously heated by energizing the heat plate 350 (step S108). Specifically, depending on the type and size of the target polyethylene pipe, for example, in the case of a normal polyethylene pipe with a nominal diameter of about 90 mm, the contact surface begins to soften when the temperature exceeds about 200°C, and 265°C. Since it can be melted and fused in a certain degree, it is heated until it is in that state.

When the butted end faces of the polyethylene pipes 110, 110 are ready to be fused, as shown in FIGS. 6(A) and 6(B), the heat plate 350 is removed and the polyethylene pipes 110, 110 are immediately butted. The end faces are brought close to each other and strongly crimped (step S110). Then, as shown in FIG. 9(B), the melted and softened resin of the butted end face portions of the polyethylene pipes 110, 110 is pushed into the annular space 412 formed by the grooves 411, 411, and enters the space 412. Is filled. Further, the resin that cannot be completely filled in the space 412 is pushed out to the inner peripheral side thereof and rises in an annular shape.

Then, this state is maintained for a while, for example, for about 3 minutes. Then, the melt-softened portion is cooled and solidified, and the polyethylene pipes 110, 110 are fused and connected to each other. Therefore, the polyethylene pipes 110, 110 are removed from the clamps 320, 320, and the outer ring manufacturing die 400, 400 is pulled out in the direction opposite to the connecting portion (steps S112 and S114). As a result, as shown in FIGS. 6C and 9C, an annular outer protrusion 120 is formed on the outer side of the welded connection portion, and an annularly raised bead 120a is also formed on the inner side thereof. It

Then, as shown in FIGS. 6(D) and 10(A), a position 10 to 30 mm away from the position where the annular outer protrusion 120 is formed is cut by a cutting machine (step S116), and then FIG. As shown in B), the cut surface of the polyethylene pipe 110 on the side where the annular outer protrusion 120 is formed is chamfered, and the annular bead 120a formed inside the outer protrusion 120 is removed from its inner surface. The inner ring 30 is formed by cutting and removing so as to leave slightly, for example, about 2 mm (step S118). As a result, the polyethylene pipe 110 serves as the pipe body 10 described above, the annular outer protrusion 120 serves as the outer ring 20, and the annular bead 120a serves as the inner ring 30. Is possible.

In the processed pipe 100 of the present invention thus formed, the outer ring 20 is made of the same resin as the pipe body 10 and is integrated with the pipe body 10. Therefore, when a separate outer ring is attached later, etc. In comparison with, the housing-type pipe joint 200 can be firmly engaged with it. Further, by providing the inner ring 30 that is integrated with the outer ring 20 inside the outer ring 20 that serves as the connecting portion, the root portion of the outer ring 20 where the stress is likely to concentrate when pipe-joined is secured. Can be reinforced.

Further, the internal resistance of the fluid flowing in the tubular body 10 can be suppressed to a low level by cutting and processing so that the annular bead 120a serving as the inner ring 30 is not left as it is but left slightly. If the tubular body 10 is thick and has sufficient strength, the inner ring 30 may be almost completely removed. In that case, the internal resistance of the fluid should be further reduced. You can When the annular bead 120a is small and does not have a large fluid internal resistance, it may be used as it is as the inner ring 30 without cutting and removing.

In addition, according to the manufacturing method of the present invention, the polyethylene pipe 110 on the cut side can be reused many times until it becomes short enough to be no longer attached to the clamp 320, and thus is not wasted. In addition, by using polyethylene as the resin forming the tubular body 10 and the outer ring 20, sufficient strength and corrosion resistance as a water pipe can be exhibited, and excellent thermoplasticity and heat-welding property can be obtained. The processed pipe 100 can be easily manufactured.

10... Pipe 20... Outer ring 30... Inner ring 100... Piping processing pipe 110... Polyethylene pipe 120... Outer protrusion 120a... Bead 200... Housing type pipe joint 210... Housing member 211... Fitting groove 220... Sealing member 300... Butt fusion machine 310... Frame 320... Clamp 330... Telescopic cylinder 340... Chamfering machine 350... Heat plate 400... Outer ring manufacturing die 410... Opening end 411... Groove 412... Space 413... Mold body

Claims (3)

A tubular body holding step of holding a pair of resin tubular bodies having substantially the same wall thickness and nominal diameter so that their open ends face each other,
Using a pair of outer ring manufacturing molds provided with an annular groove on the inner peripheral side of the opening end of the cylindrical mold body, and covering the periphery of each pipe body held in the pipe body holding step. A mold mounting step for mounting the pair of outer ring manufacturing molds, respectively,
An opening end softening step of heating and melting and softening the opening end of each of the held tubes.
A tube connecting step of connecting the opening ends of the tube softened in the opening end softening step to each other by abutting them together, and forming an annular outer ring on the outside of the connecting section by the pair of outer ring manufacturing dies. A method for producing a processed pipe for resin, which comprises: The method for manufacturing a processed pipe made of resin according to claim 1 ,
The method for producing a processed pipe for resin pipe, further comprising a bead removing step of cutting/removing a bead inside the connecting portion generated in the tube connecting step. The method for manufacturing a processed pipe for resin pipe according to claim 1 or 2 ,
The method for producing a processed pipe made of resin, wherein the resin is polyethylene.

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