JP4583226B2 - Synthetic resin pipe connection method - Google Patents

Description

  The present invention relates to a synthetic resin pipe connection method capable of connecting without damaging the performance of a wound protection layer or a locating function when connecting a synthetic resin pipe having a wound protection layer or a locating function to an outer peripheral surface.

  In recent years, synthetic resin pipes have come to be used instead of conventional metal pipes such as steel pipes as pipes used in the construction of gas pipes and water pipes buried in the ground. There is an advantage that it is excellent in durability as compared with a metal tube, and flexibility at the time of laying can effectively prevent an accident such as breakage.

  By the way, the synthetic resin pipe as described above has a structure in which the outer peripheral surface of a pipe body using polyethylene is protected by a synthetic resin wound protection layer, and a locating wire is provided outside the wound protection layer as necessary. In addition, a locating function is added so that the presence of the synthetic resin pipe can be electrically confirmed from the ground.

  Conventionally, the synthetic resin pipe connection method as described above is such that the end portions of the synthetic resin pipes that are connected to each other are peeled off over a predetermined length at the end parts of the synthetic resin pipes and the pipe body is exposed. The contact portions are pressed and connected in the axial direction and heated by butt fusion, and then the outer periphery of the connection portion is covered with a tape-shaped protective material.

  The conventional method as described above has a problem in that the protective material covering the outer periphery of the connection portion is expensive, and the winding work takes time and effort.

  Further, when the synthetic resin pipe is drawn into the ground or existing pipe by a non-opening method, there is a problem that the protective material is peeled off by earth pressure or contact resistance.

  Furthermore, the method of placing the locating wire along the outer surface of the synthetic resin tube not only requires labor and time for fixing the locating wire with an adhesive tape or the like, but the synthetic resin tube is grounded by a non-opening method. If the wire is drawn into an existing pipe, the locating wire may be broken due to earth pressure or contact resistance, and the locating wire is corroded in the soil.

  Therefore, the problem to be solved by the present invention is that the connection portion of the synthetic resin pipe can be easily and reliably protected, and the connection portion protection and locating function can be achieved even when it is pulled into the ground or an existing pipe by a non-cutting method. It is an object of the present invention to provide a synthetic resin pipe connection method that does not cause damage.

In order to solve the above problems, the present invention provides a synthetic resin in which the outer peripheral surface of a tube body is covered with a wound protection layer, and a locating tape is interposed between the tube body and the wound protection layer over the entire length of the tube body. This is a connection method for connecting pipes to each other, and the ends of each synthetic resin pipe are connected by butt fusion without peeling off the locating tape of the synthetic resin pipe and the wound protection layer. In the synthetic resin pipe connection method in which the outer peripheral bead portion is cut all around and then the locating tape is connected by a connector, sharpened claws are projected downward at a plurality of locations around a pair of metal plates, and both metal plates The connector is connected with a flexible connection part, and the connection part straddles the connection part of the synthetic resin tube so that both metal plates are connected to face the outer surface of both synthetic resin pipes. The nail of both metal plates is driven from the top of the protective layer toward the locating tape of the corresponding synthetic resin tube, and the nail penetrates the locating tape to electrically connect the locating tape of both synthetic resin tubes Then, the connector is covered with a protective layer .

  Here, in the synthetic resin pipe, the outer peripheral surface of the pipe body using polyethylene is covered with a synthetic resin wound protection layer having excellent wear resistance, and a locating tape is placed between the pipe body and the wound protection layer. It has a structure interposed over the entire length of the main body.

  The connector that connects the locating function is formed by connecting a pair of metal plates with thin line-shaped connection parts and projecting sharpened nails downward at multiple locations around the metal plate, connecting synthetic resin pipes The locating tape is electrically connected by striking the outer surface of both sides of the synthetic resin pipe connecting both metal plates so that the connection part straddles the part, and driving nails from the top of the wound protection layer toward the locating tape. Therefore, the outer surface of the connector is covered by fusion of a protective resin plate having excellent wear resistance.

According to this invention, the damage protection layer remains in the connection portion, and the protection of the connection portion can be obtained as it is, the processing of the connection portion is simplified, and the protruding portion to the outer periphery is cut by cutting the entire circumference of the bead portion. In the synthetic resin pipe connection method that does not cause damage to the connection part even if it is pulled into the ground or existing pipes by the non-opening method , sharp points are formed at multiple locations around a pair of metal plates. Since the nails protruded downwards and the locating tape was connected using a connector in which both metal plates were connected by flexible connection parts, this connector was covered with a protective layer. The locating tape can be electrically connected by simply driving it toward the locating tape from the wound protection layer, and the connector can absorb the expansion and contraction of the synthetic resin tube by the flexibility of the connection part. Can, moreover, if the trenchless method retracted into the ground and an existing pipe, the protective layer can be prevented the occurrence of damage or corrosion of locating the tape and the connector.

  Hereinafter, the structure of the synthetic resin pipe and its connecting portion according to the present invention will be described with reference to the accompanying drawings.

  FIG. 2 shows a synthetic resin pipe 1 to be connected, and the outer peripheral surface of a pipe main body 2 made of polyethylene is covered with a synthetic resin wound protection layer 3 having excellent wear resistance. It has a structure in which a locating tape 4 is interposed over the entire length of the tube body 2 between the protective layers 3, the wound protective layer 3 is transparent or translucent, and the locating tape 4 can be visually confirmed from the outside. It is like that.

  The trauma protection layer 3 is made of a thermoplastic resin having high flexibility and strength so as to follow the bending of the tube body 2, such as a polyolefin or a copolymer of polyolefin and another polymer, etc. The outer surface of the main body 2 and the locating tape 4 is formed by extrusion molding.

  Examples of the polyolefin forming the wound protective layer 3 include polyethylene, and it is preferable to use an ethylene-methacrylic acid copolymer as a copolymer of the polyolefin and another polymer.

  In addition, an ionomer resin in which molecules of an ethylene-methacrylic acid copolymer, which is a copolymer of polyolefin and another polymer, are crosslinked with metal ions can be used.

  The resin material that forms such a wound protection layer 3 has superior wear resistance than the tube body 2 and can prevent the tube body 2 from being damaged when the resin tube is drawn into the drilling hole. Since it is excellent in strength and wear resistance, the thickness can be reduced to 1.5 mm or less, the flexibility of the tube body 2 is not impaired, and the overall outer diameter of the synthetic resin tube 1 does not increase. The diameter can be reduced.

  The locating tape 4 is formed of a synthetic resin tape body 5 provided with an adhesive layer and a metal net 6 provided on the tape body 5, and the locating tape 4 is an adhesive layer of the tape body 5. It arrange | positions by affixing on the pipe | tube main body 2. FIG.

  Further, the metal net 6 of the locating tape 4 is formed in a flat tape shape with a thickness of 0.5 mm or less, and by making the locating tape 4 thin in this way, the outer diameter of the synthetic resin tube 1 as a whole is increased. Therefore, the diameter of the drilling hole can be reduced, and drawing into the existing gas pipe is advantageous.

  Further, since the metal net 6 has a width, the buried position from the ground can be accurately confirmed by the metal probe.

  3 to 5 show a connector 7 for electrically connecting the metal net 6 in the locating tape 4 of the connected synthetic resin tube 1, and a pair of rectangular metal plates 8, 8 are connected in a thin line shape. They are connected by a portion 9, and are formed by projecting downward sharpened claws 10 at a plurality of locations around the metal plates 8, 8.

  This connector 7 is manufactured by using a thin metal plate, punching and forming both the metal plates 8 and 8 together with the connecting portion 9 and the claw 10 by press molding, and bending the claw 10 downward. Are bent in opposite directions to connect the corners at the diagonal positions of the two metal plates 8, 8, and the expansion and contraction of the synthetic resin tube 1 is absorbed by the flexibility of the connecting portion 9, and the nail 10 Is set to a length that does not penetrate the thickness of the tube body 2.

  Next, a method for connecting a synthetic resin pipe will be described.

  As shown in FIG. 1 (a), the ends of the synthetic resin pipes 1 that are connected to each other are faced in a state where the wound protection layer 3 of the synthetic resin pipe 1 is not peeled off, and the ends are in contact with each other. A well-known butt fusion machine is set on the outside of the abutting portion, and the abutting portion is heated by applying an axial force to the abutting portion of the synthetic resin tube 1, thereby fusing.

  By such fusion, the wound protection layer 3 is melted together with the tube main body 2 at the connection portion, and the bead portion 11 is raised outside the fusion portion as shown in FIG.

  After the completion of the fusion, the butt fusion machine is removed, and instead of this, a known bead cutter is set on the connection portion, and the outer periphery of the bead portion 11 is cut and removed as shown in FIG. The outer diameter of the is finished to match the outer diameter of the synthetic resin tube.

  Next, as shown in FIG. 3, the connector 7 is connected to the butt connection portion of the locating tape 4 in the synthetic resin tube 1, and the both-side synthetic resin tube is connected to the metal plates 8, 8 across the connection portion 9. The nail | claw 10 of both the metal plates 8 and 8 is driven in toward the locating tape 4 from the top of the wound protection layer 3 so that it may be located in 1 outer surface.

  As shown in FIG. 4, the connector 7 has metal claws 10 of both metal plates 8, 8 penetrating through the metal net 6 of the wound protection layer 3 and the locating tape 4, thereby connecting the metal nets 6 of the both sides of the synthetic resin tube 1. Will be electrically connected.

  Thereafter, as shown in FIGS. 1D and 4, a protective resin plate 12 having a larger abrasion resistance than that of the connector 7 is stacked on the outer surface of the connector 7, and a resin plate fusion machine is set on the outer side. If the protective resin plate 12 is fused to the outer surface of the synthetic resin tube 1 by heating the protective resin plate 12 for a predetermined time and then cooling it, the protection process for the connector 7 is completed.

  Further, the protective performance of the connector 7 may be protected by winding a protective tape having a short working time although the protective performance is somewhat reduced.

  The protective resin plate 12 is preferably made of a material having wear resistance and adhesiveness like the wound protective layer 3 and transparent so that the connector 7 can be visually confirmed.

  As shown in FIG. 4, the connecting portions of the synthetic resin pipes 1 connected as described above are fused together by melting the end faces of the pipe main body 2, so that sufficient connection strength can be obtained and the connection portions are connected. The damage protection layer 3 remains in the portion, so that the protection of the connection portion can be obtained as it is, the processing of the connection portion is simplified, and the metal net 6 of the locating tape 4 can be electrically connected by the connector 7. In addition, since the outer surface of the connector 7 is covered with the protective resin plate 12 and the protective tape, if the synthetic resin pipe 1 is drawn into the ground or existing pipe by a non-opening method, the locating function and the damage to the connector 7 The occurrence of corrosion can be prevented.

  In the illustrated example, the synthetic resin pipe 1 is provided with the locating tape 4, but the synthetic resin pipe 1 without the locating tape 4 can be similarly connected, You may make it finish the part which cut the bead part 11 by winding of the protection tape.

  Here, the synthetic resin pipe 1 embedded in the ground is used for construction of a gas pipeline or a water supply pipeline.

(A) thru | or (d) is a perspective view which shows the process of the connection construction method of a synthetic resin pipe in order Longitudinal sectional view enlarging the main part of the synthetic resin pipe Partially cutaway plan view showing the connection part of a synthetic resin pipe in an enlarged manner Longitudinal front view showing the connection part of a synthetic resin pipe in an enlarged manner Perspective view of the connector used to connect the locating tape

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Synthetic resin pipe 2 Pipe main body 3 Damage protection layer 4 Locating tape 5 Tape main body 6 Metal net 7 Connector 8 Metal plate 9 Connection part 10 Claw 11 Bead part 12 Protective resin board

Claims (1)

This is a connection method for connecting the synthetic resin pipes with the outer peripheral surface of the pipe body covered with a wound protection layer and interposing the locating tape between the pipe body and the wound protection layer over the entire length of the pipe body. Without detaching the locating tape and the wound protection layer of the synthetic resin pipe to be connected, the ends of each other are connected by butt fusion, and the outer peripheral bead generated at this connection part is cut all around and then locating In the connection method of the synthetic resin pipe that connects the tape with the connector,
Using a connector in which sharpened claws are projected downward at a plurality of locations around a pair of metal plates, and both metal plates are connected by flexible connecting portions, the connecting portions straddle the connecting portion of the synthetic resin tube With the two metal plates facing each other so that they are positioned on the outer surfaces of the two synthetic resin pipes, the nails of both metal plates are driven toward the locating tape of the corresponding synthetic resin tube from above the wound protection layer. A synthetic resin pipe connection method characterized by electrically connecting the locating tapes of both synthetic resin pipes by penetrating the locating tape, and then covering the connector with a protective layer .

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