JP6674676B2 - Piping connection structure, piping connection method and sheet tape - Google Patents

Description

  The present invention relates to a pipe connection structure, a pipe connection method, and a sheet-like tape for covering the vicinity of a connection point with another pipe in a pipe used as a transportation means of fluid such as clean water, sewage, and air. About.

  BACKGROUND ART Plastic pipes such as polyethylene pipes are widely used as means for transporting fluids such as clean water, sewage, and air. Such a plastic pipe is lighter in weight than a metal pipe and therefore has excellent workability. Moreover, it is hard to be oxidized and thus has excellent corrosion resistance, and also has excellent flexibility and is excellent in earthquake resistance. Here, when the diameter of the plastic pipe is relatively large, a plurality of plastic pipes having a length of about several meters are transported to the construction site, and the ends of the plastic pipes are connected to each other at the construction site for a long distance. Formed a fluid transport path.

  As a method of connecting the pipe ends of the plastic pipe, a connection point at an end of the plastic pipe is covered with a joint, and a heating wire provided on the inner peripheral face of the joint is heated to generate heat. A method of electro-fusing the outer peripheral surface of the end portion (electrofusion (EF) fusion method) or a method of directly fusing the edges of the plastic tube by directly heating and melting the edge of the plastic tube with a heater. Conventionally, there are known a butt fusion method, a method of connecting pipes by a mechanical joint, and the like.

  Further, Patent Literature 1 discloses a technique in which a connection portion of a plastic pipe is covered with a high-strength fiber sheet having high heat resistance to reinforce the pressure resistance of the connection portion of the plastic pipe. Patent Literature 2 discloses a method for connecting pipe ends of a plastic pipe in which a fiber reinforcing material is spirally wound between a tubular inner layer and an outer layer formed of a thermoplastic resin. ing. In the method of connecting the ends of plastic tubes disclosed in Patent Document 2, the outer layer is cut off from both ends of the plastic tube, and the inner layer is exposed by unwinding the fiber reinforcing material, and the inner layers are butt-connected. After fusion, the unwound fiber reinforcement is wound around the outer periphery of the inner layer again, and another fiber reinforcement is wound around the outer periphery spirally or at right angles to the tube axis direction so as to straddle both pipe ends. ing.

  Further, Patent Literature 3 discloses a connection structure between a multi-layer tube whose outer peripheral surface is covered with a reinforcing layer and another tube, and which has an excellent pressure resistance effect. In the pipe connection structure disclosed in Patent Literature 3, the connection end of the pipe and the connection end face of the joint are welded by a weld, and then at least the surface of the weld is covered and the length of the thread in the circumferential direction of the pipe is increased. The tube is covered with a filament wrapped so that the directions are aligned and a fiber reinforced resin layer formed from a cloth covering the filament. In such a pipe connection structure, the vicinity of the welded portion is reinforced in the circumferential direction, so that the pressure resistance effect is excellent. Further, Patent Document 4 discloses a pipe which can reliably secure internal pressure resistance of a connection portion and is excellent in workability even when a pipe joint such as an electrofusion (EF) joint is used in a connection portion between resin pipe bodies. Is disclosed. In the pipe connection structure disclosed in Patent Literature 4, after a step formed at the boundary between the pipe and the pipe joint at both ends of the pipe joint is filled with a spacer, the outer peripheral front surface from the pipe to the connection section including the pipe joint is filled. Is covered with a reinforcing material.

JP-A-11-336958 Patent No.4183028 JP 2015-175482 A JP 2012-251628 A

  When reinforcing the connection point of the plastic pipe, if there is a step at the connection point, even if the connection point of the plastic pipe is covered with a reinforcing material such as a fiber reinforcing material, the plastic pipe may be heated or pressured. There is a problem that a sufficient internal pressure reinforcing effect cannot be obtained because the reinforcing material is shifted from the inner pipe portion due to expansion and contraction in the pipe axis direction, or the reinforcing material is expanded when an internal pressure is applied. Further, if the reinforcing member is displaced from the inner tube portion and the inner tube portion is exposed, the plastic tube may be broken from the exposed portion. For this reason, even when there is a step in the connection portion, it is necessary to prevent the inner tube portion from being exposed, and the displacement and loosening of the reinforcing material.

  In order to cope with such a problem, when connecting a plastic pipe by an electrofusion (EF) fusion method, a lock ring and a flange are provided around the plastic pipe near both ends of the joint, respectively, and a pair of flanges is provided. A lock ring system may be used in which the flanges are connected by a rod-shaped member such as a bolt. In such a lock ring method, even if the plastic pipe expands and contracts in the pipe axis direction due to heat or pressure, the position of the lock ring provided near the both end edges of the joint does not change, so that the reinforcing material is displaced and the plastic pipe is displaced. It is possible to prevent the inner tube portion from being exposed. However, such a lock ring system is expensive and heavy because it is made of metal, so it is difficult to attach the lock ring and the flange at the work site for laying pipes, and there is a problem that the usability is poor. .

  The present invention has been made in view of such a point, and it is possible to reinforce the pressure resistance of a connection point with another pipe at the end of the pipe by an inexpensive and simple operation. It is an object of the present invention to provide a pipe connection structure and a pipe connection method capable of preventing the inner pipe portion from being exposed because the tape does not shift from the inner pipe portion even when the tape is expanded and contracted in the axial direction. Aim.

  Another object of the present invention is to make it possible to reinforce the pressure resistance of the connection portion of the pipe with the other pipe at the end of the pipe by an inexpensive and simple operation. An object of the present invention is to provide a sheet-like tape which can prevent the pipe from being displaced from an inner pipe portion even when the pipe expands and contracts in the pipe axis direction when attached.

  The pipe connection structure of the present invention is an inner pipe portion formed of a thermoplastic resin, a pipe having a reinforcing member wound around the outer peripheral surface of the inner pipe portion and a covering member that covers the reinforcing member, and a plurality of fibers. A sheet-like tape extending in the longitudinal direction and wherein the fibers are held by a thermoplastic resin, wherein at least an exposed portion of the inner pipe portion in the pipe is in a state of being thermally fused to the tape, and the tape The end portion of the pipe is covered with the tape so that the fibers are substantially perpendicular to the pipe axis direction of the pipe.

  According to such a pipe connection structure, a plurality of fibers extend in the longitudinal direction, and these fibers are held by a sheet-like tape held by a thermoplastic resin in the vicinity of a connection point with another pipe at an end of the pipe. At this time, at least the exposed portion of the inner pipe portion in the pipe was heat-fused to the tape and each fiber of the tape was substantially perpendicular to the pipe axis direction of the pipe. The pressure-resistant reinforcement of the connection part with the other pipe at the end can be performed with low cost and simple work, and the tape does not shift from the inner pipe part even if the pipe expands and contracts in the pipe axis direction. It is possible to prevent the inner tube portion from being exposed.

  In the pipe connection structure of the present invention, at least a part of the exposed portion of the reinforcing member in the pipe may be in a state of being thermally fused to the tape.

  In this case, a part of the covering member in the pipe may be in a state of being thermally fused to the tape.

  In the pipe connection structure of the present invention, the reinforcing member may be one in which fibers are held by a thermoplastic resin.

  In the pipe connection structure of the present invention, a part of an exposed portion of the inner pipe portion at an end of the pipe may be covered with a joint.

  In this case, the pipe may be covered with the tape at least from the edge of the joint.

  Further, an inner peripheral surface of the joint may be attached to an outer peripheral surface of the inner pipe portion of the pipe by electric fusion.

  In this case, the tape may be in a state of being thermally fused to the inner peripheral surface of the joint at a location of a gap between the outer peripheral surface of the inner pipe portion in the pipe and the inner peripheral surface of the joint. Good.

  The pipe connection method of the present invention connects a pipe having an inner pipe portion formed of a thermoplastic resin, a reinforcing member wound around the outer peripheral surface of the inner pipe portion, and a covering member covering the reinforcing member to another pipe. A method of connecting a pipe to be exposed, wherein at least a step of exposing at least the inner pipe portion in the vicinity of a connection point with another pipe in the pipe, a step of connecting the pipe to another pipe, and at least the step of connecting the pipe to another pipe. At the exposed portion of the inner tube portion, a plurality of fibers are extended in the longitudinal direction and a sheet-shaped tape in which the fibers are held by a thermoplastic resin is heat-fused. A step of coating the tape in the vicinity of a connection point with another pipe at an end of the pipe so as to be substantially orthogonal to the pipe axis direction.

  According to such a pipe connection method, at least at the exposed portion of the inner pipe portion in the pipe, a plurality of fibers extend in the longitudinal direction, and the fibers are heat-fused with a sheet-like tape in which the fibers are held by a thermoplastic resin, At this time, by covering the tape near the connection point with another pipe at the end of the pipe so that each fiber of the tape is substantially orthogonal to the pipe axis direction of the pipe, another fiber at the end of the pipe is It is possible to reinforce the pressure resistance of the connection point with the pipe by inexpensive and simple work.Moreover, even if the pipe expands and contracts in the pipe axis direction, the tape does not shift from the inner pipe part, so this inner pipe part is Exposure can be prevented.

  In the pipe connection method of the present invention, in the step of coating the tape in the vicinity of a connection point with another pipe at the end of the pipe, at least a part of the exposed location of the reinforcing member in the pipe, The tape may be heat-sealed.

  In this case, in the step of coating the tape in the vicinity of a connection point with another pipe at the end of the pipe, the tape is thermally fused to a part of the coating member in the pipe. Is also good.

  The sheet-like tape of the present invention is a sheet-like tape for covering the vicinity of a connection point of a pipe with another pipe, and a plurality of fibers extending in a longitudinal direction, and a thermoplastic resin holding the fibers. And characterized in that:

  According to such a sheet-shaped tape, the tape is heat-sealed at least at the exposed portion of the inner pipe portion in the pipe, and at this time, each fiber of the tape is substantially orthogonal to the pipe axis direction of the pipe, By coating the tape near the connection with the other pipe at the end of the pipe, it is possible to reinforce the pressure resistance of the connection with the other pipe at the end of the pipe by inexpensive and simple work, and Even if the pipe expands and contracts in the pipe axis direction, the tape does not shift from the inner pipe part, so that the inner pipe part can be prevented from being exposed.

  The sheet-shaped tape of the present invention may further include a connecting member that connects between the adjacent fibers.

  In this case, the connection member may extend substantially perpendicular to the direction in which the fibers extend.

  Further, the connection member may be thinner than the fiber.

  In the sheet-shaped tape of the present invention, the size of the fiber and the thermoplastic resin is determined by a ratio of an area occupied by the fiber to an adhesion area between the pipe and the tape when the pipe is covered with the tape. However, the size may be smaller than the ratio of the area occupied by the thermoplastic resin to the bonding area.

  In the sheet-like tape of the present invention, the fibers may be aramid fibers.

  In the sheet-like tape of the present invention, the fibers may be included in the thermoplastic resin.

  ADVANTAGE OF THE INVENTION According to the piping connection structure and the piping connection method of this invention, the pressure-proof reinforcement of the connection part with the other piping in the end part of a piping can be performed by cheap and simple work, and also the piping is a pipe axial direction. Even if the tape expands and contracts, the tape does not shift from the inner tube portion, so that the inner tube portion can be prevented from being exposed.

  Further, according to the sheet-like tape of the present invention, it is possible to carry out pressure-resistant reinforcement of a connection point with another pipe at an end of the pipe by an inexpensive and simple operation, and, furthermore, to expose an inner pipe portion of the pipe at an exposed portion. Even when the pipe is expanded and contracted in the pipe axis direction when it is thermally fused to the inner pipe, it can be prevented from being displaced from the inner pipe portion.

It is a perspective view showing appearance of piping connected with other piping in an embodiment of the invention. It is sectional drawing which shows the state before the piping is covered with the sheet-shaped tape in the connection structure of the piping by embodiment of this invention. It is sectional drawing which shows an example of the state after the piping was covered with the sheet-shaped tape in the piping connection structure by embodiment of this invention. (A) (b) is a perspective view which shows the external appearance of the connection structure of the piping shown in FIG. FIG. 4 is a cross-sectional view showing another example of a state after the pipe is covered with a sheet-like tape in the pipe connection structure according to the embodiment of the present invention. It is sectional drawing which shows the state after the pipe was covered with the sheet-shaped tape in the pipe connection structure by embodiment of this invention. It is sectional drawing which shows the state after the pipe was covered with the sheet-shaped tape in the pipe connection structure by embodiment of this invention. It is sectional drawing which shows the example of the state after the pipe connected by the butt fusion method in the pipe connection structure by embodiment of this invention was covered with the sheet-shaped tape. It is a perspective view showing composition of a sheet-like tape used for a pipe connection structure by an embodiment of the invention. FIG. 10 is a perspective view illustrating a configuration of a roll when the sheet-like tape illustrated in FIG. 9 is wound around a core.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 10 are views showing a pipe connection structure according to the present embodiment and a sheet-like tape used in such a pipe connection structure. FIG. 1 is a perspective view showing an appearance of a pipe to be connected to another pipe in the present embodiment, and FIG. 2 is a pipe-shaped tape in the pipe connection structure according to the present embodiment. FIG. 4 is a cross-sectional view showing a state before being covered with a. FIG. 3 is a cross-sectional view showing an example of a state after the pipe is covered with a sheet-like tape in the pipe connection structure according to the present embodiment, and FIGS. FIG. 2 is a perspective view showing an appearance of a pipe connection structure shown in FIG. FIGS. 5 to 7 are cross-sectional views showing other examples of the state after the pipe is covered with the sheet-shaped tape in the pipe connection structure according to the present embodiment, and FIG. It is sectional drawing which shows the example of the state after the pipe connected by the butt fusion method in the pipe connection structure by embodiment was covered with the sheet-shaped tape. FIG. 9 is a perspective view showing a configuration of a sheet-like tape used in the pipe connection structure according to the present embodiment. FIG. 10 is a diagram in which the sheet-like tape shown in FIG. 9 is wound around a core. FIG. 3 is a perspective view showing a configuration of a winding body when the vehicle is in the state.

  First, the configuration of pipes to be connected by the pipe connection structure according to the present embodiment will be described with reference to FIG. As shown in FIG. 1, a pipe 10 to be connected by the pipe connection structure according to the present embodiment includes an inner pipe portion 12 formed of a high-density thermoplastic resin such as polyethylene resin, and an inner pipe portion 12. It has a reinforcing member 14 wound around the outer peripheral surface and a covering member 16 that covers the reinforcing member 14. Here, as the reinforcing member 14, for example, an aramid tape in which a plurality of aramid fibers extend in the longitudinal direction and the aramid fibers are held by a sheet-like thermoplastic resin is used. The reinforcing member 14 is spirally or circumferentially wound around the inner tube portion 12. With such a reinforcing member 14, the pressure resistance of the pipe 10 is strengthened. Further, the covering member 16 is formed of, for example, a thermoplastic resin such as a low-density polyethylene resin, and the reinforcing member 14 wound around the inner pipe portion 12 is covered with the covering member 16 so that the reinforcing member 14 is exposed to the external environment. From being protected.

  Next, an example of a pipe connection structure according to the present embodiment will be described with reference to FIGS.

  As a method of connecting the pipe ends of the pipe 10 as shown in FIG. 1, a connection point at an end of the pipe 10 is covered with a joint 20, and a heating wire 26 (described later) provided near an inner peripheral surface of the joint 20. Is generated so that the inner peripheral surface of the joint 20 and the outer peripheral surface of the end of the pipe 10 are electrically fused (electrofusion (EF) fusion method). Here, as shown in FIGS. 2 and 4, the joint 20 is formed in a cylindrical shape, and a heating wire 26 is wound, for example, in a spiral shape near the inner peripheral surface of the joint 20. A pair of electrodes 22 and 24 provided on the outer peripheral surface of the joint 20 are connected to both ends of the heating wire 26. When a voltage is applied between these electrodes 22 and 24 and a current flows through the heating wire 26 to generate heat, the inner peripheral surface of the joint 20 and the outer peripheral surface of the end of the pipe 10 inserted into the joint 20 are formed. Are melted, the inner peripheral surface of the joint 20 and the outer peripheral surface of the end of the pipe 10 are electrically fused.

  In performing such an electric fusion method, first, the inner pipe portion 12 and the reinforcing member 14 are exposed in the vicinity of a connection point of the pipe 10 with another pipe as shown in FIG. This is to ensure that a sheet-shaped tape 30 described later is thermally fused to the inner tube portion 12. Then, as shown in FIG. 2, each end of the two pipes 10 to be connected is inserted into the joint 20, and the ends of the pipes 10 are brought into contact inside the joint 20. Thereafter, when a voltage is applied between the electrodes 22 and 24 of the joint 20 and a current is caused to flow through the heating wire 26 to generate heat, the inner peripheral surface of the joint 20 and the outer peripheral surface of the end of each pipe 10 are electrically fused. At the same time, the ends of the pipe 10 are firmly connected inside the joint 20. The connection structure of the pipe before the pipe 10 is covered with the sheet-shaped tape 30 described later is indicated by reference numeral 1 in FIG.

  Then, after the edges of the pipes 10 are connected to each other inside the joint 20, as shown in FIGS. 3 and 4, the exposed portions of the inner pipe portion 12, the exposed portions of the reinforcing member 14, and the covering members A part of the sheet 16 is wound with a sheet-shaped tape 30 to be described later and heat-sealed. FIG. 4A shows each of the fibers 34 (described later) in the sheet-shaped tape 30 in order to make the configurations of the inner tube portion 12, the reinforcing member 14, and the covering member 16 covered with the sheet-shaped tape 30 easier to see. The illustration is omitted, and FIG. 4B shows the inner tube portion 12 covered with the sheet-shaped tape 30 in order to make the configuration of each fiber 34 (described later) in the sheet-shaped tape 30 easier to see. Illustration of the reinforcing member 14 and the covering member 16 is omitted.

  As shown in FIG. 4B, a sheet-shaped tape 30 described later is wound around the exposed portion of the inner tube portion 12, the exposed portion of the reinforcing member 14, and a part of the covering member 16 in each pipe 10 and thermally fused. At this time, each fiber 34 (described later) of the sheet-shaped tape 30 is substantially perpendicular to the pipe axis direction of the pipe 10 (that is, each fiber 34 extends in the circumferential direction of the pipe 10). The sheet-shaped tape 30 is covered. In this manner, a pipe connection structure 1a is formed in which the pipe 10 is covered with the sheet-shaped tape 30 from both end edges of the joint 20. In such a pipe connection structure 1a, by covering the pipe 10 with the sheet-shaped tape 30 from both end edges of the joint 20, it is possible to reinforce the pressure resistance of the end of the pipe 10 at a connection point with another pipe. Become like Here, the details of the configuration of the sheet-like tape 30 that covers the pipe 10 in the pipe connection structure 1a as shown in FIGS. 3 and 4 will be described with reference to FIGS.

  As shown in FIG. 9, the sheet-like tape 30 includes a plurality of longitudinally extending fibers 34, a sheet-like thermoplastic resin 32 that holds the fibers 34, and a connecting member 36 that connects between the adjacent fibers 34. And Here, each fiber 34 is composed of a linear fiber filament or the like, and for example, aramid fiber is used as each fiber 34. As the sheet-like thermoplastic resin 32, a transparent or translucent resin having a low melting point is used. For example, the melting point of the thermoplastic resin 32 is about 130 ° C., which is sufficiently lower than the melting point of each fiber 34. For example, polyethylene is used as such a sheet-like thermoplastic resin 32. Further, each fiber 34 is included in the sheet-like thermoplastic resin 32, and each fiber 34 is not exposed on the outer surface of the sheet-like tape 30. Instead of enclosing each fiber 34 in the thermoplastic resin 32, each fiber 34 is disposed on the surface of the sheet-like thermoplastic resin 32, and only one surface of each fiber 34 is buried in the thermoplastic resin 32. Each fiber 34 may adhere to the thermoplastic resin 32 in the form. That is, if at least a part of the surface of each fiber 34 adheres to the surface of thermoplastic resin 32, each fiber 34 does not necessarily need to be included in thermoplastic resin 32. When each fiber 34 is included in the thermoplastic resin 32, when the sheet-shaped tape 30 is heat-sealed to the inner tube portion 12, the thermoplastic resin 32 is applied to the outer peripheral surface of the inner tube portion 12. It is more preferable to arrange the sheet-shaped tape 30 so as to face the surface on the side that contacts more.

  Each connecting member 36 is formed of a linear member (for example, a linear fiber), and these connecting members 36 extend substantially perpendicular to the direction in which the fiber 34 extends. By such a connecting member 36, it is possible to maintain the interval between the adjacent fibers 34 at equal intervals. This makes it possible to prevent the sheet-shaped tape 30 from expanding in the direction orthogonal to the direction in which the fibers 34 extend due to pressure. Further, each connecting member 36 is thinner than the fiber 34 composed of a fiber filament or the like.

  The size of the fiber 34 and the thermoplastic resin 32 is such that the ratio of the area occupied by the fiber 34 to the adhesion area between the pipe 10 and the sheet-shaped tape 30 when the pipe 10 is covered with the sheet-shaped tape 30 is: The size is smaller than the ratio of the thermoplastic resin 32 to the bonding area. That is, the distance between the adjacent fibers 34 in the thermoplastic resin 32 is larger than the width of the fibers 34. The sheet-like tape 30 according to the present embodiment is not limited to such an embodiment. The thickness and number density of the fibers 34 in the sheet-like tape 30, the abundance ratio of the fibers 34 and the thermoplastic resin 32, and the like are determined based on the diameter of the pipe 10 to be connected, the pressure resistance, the strength of the fibers 34, and the like. The value may be designed.

  A method for manufacturing such a sheet-shaped tape 30 will be described below. First, a plurality of longitudinally extending fibers 34 are arranged at equal intervals on the surface of a belt-like thermoplastic resin, and these belt-like thermoplastic resins and each fiber 34 are sent between a pair of heat rollers to form a pair of heat rollers. Pressing while heating between rollers. Then, another belt-shaped thermoplastic resin is superimposed on the surface of the belt-shaped thermoplastic resin on the side where each fiber 34 is provided, and a pair of thermoplastic resins in a state where each fiber 34 is sandwiched therebetween is again paired with a pair. The sheet is sent between the heat rollers and pressed while being heated between the pair of rollers. As a result, the sheet-like tape 30 in which the respective fibers 34 are included in the sheet-like thermoplastic resin 32 is manufactured.

  When covering the pipe 10 with the sheet-like tape 30 as shown in FIG. 9, the surface B on the side opposite to the side A on which the fibers 34 are provided exposes the inner pipe portion 12 of the pipe 10. The portion, the exposed portion of the reinforcing member 14 and a part of the covering member 16 are brought into contact with each other. Specifically, after the thermoplastic resin 32 is melted by burning the surface B of the sheet-shaped tape 30 with a burner, the exposed portion of the inner tube portion 12 in the pipe 10, the exposed portion of the reinforcing member 14, and the covering member 16 are exposed. By adhering this surface B to a part of the outer peripheral surface, these portions in the pipe 10 and the sheet-shaped tape 30 are heat-sealed. When the inner tube portion 12 is formed of polyethylene resin and the thermoplastic resin 32 in the sheet-like tape 30 is polyethylene, the material polyethylene has a property that the materials can be bonded to each other by heat fusion. Therefore, there is an advantage that the sheet-shaped tape 30 can be more firmly heat-sealed to the exposed portion of the inner tube portion 12.

  Further, as shown in FIG. 10, a winding body 40 is configured by winding a sheet-shaped tape 30 as shown in FIG. At this time, each fiber 34 of the sheet-shaped tape 30 is in a state of extending in the circumferential direction of the winding body 40. Then, the pipe 10 is covered with the sheet-shaped tape 30 unwound from the winding body 40 and cut.

  As shown in FIG. 2, after the ends of the pipes 10 are connected to each other inside the joint 20, the exposed portions of the inner pipe portion 12, the exposed portions of the reinforcing member 14, and a part of the covering member 16 in each pipe 10 are described above. When the sheet-shaped tape 30 is wound and heat-sealed, the exposed portion of the inner tube portion 12, the exposed portion of the reinforcing member 14, and a part of the covering member 16 are heat-sealed to the sheet-shaped tape 30, respectively. Therefore, even if the pipe 10 expands and contracts in the pipe axis direction due to heat and pressure, the sheet-shaped tape 30 does not shift from the pipe 10. More specifically, since the inner tube portion 12, the reinforcing member 14, and the covering member 16 are each formed of a thermoplastic resin such as a polyethylene resin, the inner tube portion 12, the reinforcing member 14, and the covering member 16 When the heat is applied by winding the tape 30, the outer peripheral surface of the inner tube portion 12, the reinforcing member 14, the covering member 16, and the thermoplastic resin 32 of the sheet-shaped tape 30 are melted, respectively, and the inner tube portion 12 and the reinforcing member are reinforced. The outer peripheral surfaces of the member 14 and the covering member 16 and the thermoplastic resin 32 of the sheet-like tape 30 are thermally fused. For this reason, even if the pipe 10 expands and contracts in the pipe axis direction and the circumferential direction due to heat and pressure, the inner pipe portion 12 adjacent to the edge of the joint 20 is not exposed, and 12 can be prevented from being destroyed. More specifically, the outer peripheral surface of the inner tube portion 12 at both end edges of the joint 20 and the thermoplastic resin 32 of the sheet-shaped tape 30 are heat-sealed, so that the inner tube portion 12 and the sheet-shaped tape 30 are fused. Since the tape 30 and the tape 30 are firmly bonded to each other, the sheet-shaped tape 30 is prevented from being displaced from the inner tube portion 12 in a direction away from the edge of the joint 20. The inner tube portion 12 is prevented from being exposed. The sheet-like tape 30 is attached to the pipe 10 such that the fibers 34 of the sheet-like tape 30 are substantially orthogonal to the pipe axis direction of the pipe 10 (that is, each fiber 34 extends in the circumferential direction of the pipe 10). , It is possible to prevent the inner pipe portion 12 of the pipe 10 from expanding in the radial direction due to pressure near the end edge of the joint 20. As described above, each fiber 34 in the sheet-like tape 30 is used for reinforcing the connection portion of the pipe 10, and the thermoplastic resin 32 has a function of holding each fiber 34 and the inner pipe portion 12 of the pipe 10. The reinforcing member 14 and the covering member 16 are used as a member having a function of heat fusion.

  In the pipe connection structure 1a as shown in FIGS. 3 and 4, a part of the coating member 16 in the pipe axis direction of the pipe 10 (specifically, the coating member 16 on the side near the exposed portion of the reinforcing member 14). Is partly thermally fused to the sheet-shaped tape 30 over the entire circumferential direction, but the present embodiment is not limited to such an aspect. As another example, a part of the covering member 16 in the circumferential direction of the pipe 10 may be in a state of being thermally fused to the sheet-shaped tape 30 (for example, in units of 90 ° in the circumferential direction of the pipe 10). .

  It is preferable that the exposed portion of the inner pipe portion 12 and the exposed portion of the reinforcing member 14 in the pipe 10 are covered with a sheet-like tape 30, and then the sheet-like tape 30 is covered with a light-shielding member (not shown). When aramid fibers are used as the fibers 34 of the sheet-like tape 30, the aramid fibers are weak to light. It is possible to prevent the constituent aramid fibers from being damaged by light such as sunlight.

  Further, the pipe connection structure according to the present embodiment is not limited to those shown in FIGS. As another example of the pipe connection structure according to the present embodiment, as shown in FIG. 5, only the exposed portions of the inner pipe portion 12 and the exposed portions of the reinforcing member 14 of the pipe 10 are thermally fused to the sheet-like tape 30. A pipe connection structure 1b may be used in which the vicinity of a connection point with another pipe 10 at the end of the pipe 10 is covered with a sheet-like tape 30 so as to be in a state of being cut. In such a pipe connection structure 1b, similarly to the above-described pipe connection structure 1a, the pipe 10 is covered with the sheet-shaped tape 30 from both end edges of the joint 20. Also in such a pipe connection structure 1b, the exposed portion of the inner pipe portion 12 and the exposed portion of the reinforcing member 14 are each in a state of being thermally fused to the sheet-like tape 30, and each fiber 34 of the sheet-like tape 30 is also provided. Is substantially orthogonal to the pipe axis direction of the pipe 10, so that even if the pipe 10 expands or contracts in the pipe axis direction due to heat or pressure, the sheet-shaped tape 30 does not shift from the pipe 10. Further, in the pipe connection structure 1b shown in FIG. 5, all of the exposed portions of the inner pipe portion 12 and all of the exposed portions of the reinforcing member 14 in the pipe 10 are in a state of being thermally fused to the sheet-like tape 30. However, the present embodiment is not limited to such a mode. As another example, all of the exposed portions of the inner pipe portion 12 and part of the exposed portions of the reinforcing member 14 in the pipe 10 may be in a state where they are thermally fused to the sheet-shaped tape 30. Specifically, a part of the exposed portion of the reinforcing member 14 in the pipe axis direction of the pipe 10 (specifically, a part of the exposed portion of the reinforcing member 14 on the side closer to the exposed portion of the inner pipe portion 12) is circumferential. It may be in a state of being thermally fused to the sheet-like tape 30 over the entire direction, or a part of the exposed portion of the reinforcing member 14 in the circumferential direction of the pipe 10 (for example, in the circumferential direction of the pipe 10). It may be in a state of being thermally fused to the sheet-like tape 30 (in units of 90 °).

  As still another example of the pipe connection structure according to the present embodiment, as shown in FIG. 6, only the exposed portion of the inner pipe portion 12 in the pipe 10 is in a state of being thermally fused to the sheet-like tape 30. A pipe connection structure 1 c may be used in which the vicinity of a connection point with another pipe 10 at the end of the pipe 10 is covered with a sheet-like tape 30. In such a pipe connection structure 1c, the pipe 10 is covered with the sheet-shaped tape 30 from both end edges of the joint 20, similarly to the above-described pipe connection structures 1a and 1b. Also in such a pipe connection structure 1c, the exposed portions of the inner pipe portion 12 and the exposed portions of the reinforcing member 14 are each thermally fused to the sheet-like tape 30, and the respective fibers 34 of the sheet-like tape 30 are formed. Is substantially orthogonal to the pipe axis direction of the pipe 10, so that even if the pipe 10 expands or contracts in the pipe axis direction due to heat or pressure, the sheet-shaped tape 30 does not shift from the pipe 10.

  As still another example of the pipe connection structure according to the present embodiment, as shown in FIG. 7, a part of a sheet-like tape 30 is formed on the outer circumference of the inner pipe portion 12 of the pipe 10 and the inner circumference of the joint 20. Between the outer peripheral surface of the inner pipe portion 12 of the pipe 10 and the inner peripheral surface of the joint 20, and heat-fused to the inner peripheral surface of the joint 20. A pipe connection structure 1d in a state of being connected may be used. In such a pipe connection structure 1d, a part of the sheet-like tape 30 is attached to the inner peripheral surface of the joint 20 at a gap between the outer peripheral surface of the inner pipe portion 12 and the inner peripheral surface of the joint 20 in the pipe 10. Since the sheet 30 is in a heat-sealed state, a part of the sheet-like tape 30 is firmly adhered to the joint 20 and also firmly adhered to the inner tube portion 12 and the covering member 16 of the pipe 10. Even if the pipe 10 expands or contracts in the pipe axis direction due to heat or pressure, the distance between the joint 20 and the covering member 16 of each pipe 10 can be kept constant, so that the inner pipe portion near the end edge of the joint 20 can be maintained. 12 can be more reliably prevented from being exposed.

  As shown in FIG. 7, a part of the tape such as the sheet-shaped tape 30 has a gap between the outer peripheral surface of the inner tube portion 12 of the pipe 10 and the inner peripheral surface of the joint 20. In the case where the tape is thermally fused to the surface, the tape is not limited to the above-described sheet-shaped tape 30. An aramid tape used as the reinforcing member 14 is coated on the pipe 10 so as to cover at least an exposed portion of the inner pipe portion 12 in the pipe 10, and a part of the aramid tape is applied to an outer peripheral surface of the inner pipe portion 12 in the pipe 10. The joint 20 may be thermally fused to the inner peripheral surface of the joint 20 at the location of the gap between the inner peripheral surface of the joint 20 and the inner peripheral surface of the joint 20. Even in such a method, when the pipe 10 expands or contracts in the pipe axis direction due to heat or pressure, the distance between the joint 20 and the covering member 16 of each pipe 10 (that is, the exposure of the inner pipe portion 12 and the reinforcing member 14). (The length of the portion in the pipe axis direction) is kept constant, so that it is possible to prevent the inner pipe portion 12 near the end edge of the joint 20 from being exposed.

  Further, the pipe connection structure and the pipe connection method according to the present invention are not limited to those using the electrofusion (EF) fusion method. A butt fusion method in which the edges of the pipe 10 are directly fused to each other by directly heating and melting the edge of the pipe 10 by a heater may use the pipe connection structure and the pipe connection method according to the present invention. It may be. Such a pipe connection structure will be described with reference to FIG.

  FIG. 8 is a diagram showing a pipe connection structure 2 in which a sheet-like tape 30 covers the pipe 10 connected by the butt fusion method. In forming the pipe connection structure 2 as shown in FIG. 8, first, as shown in FIG. 1, the inner pipe portion 12 and the reinforcing member 14 are exposed in the vicinity of a connection point between the pipe 10 and another pipe. Then, the edges of the pipe 10 are directly heated and melted by a heater to directly thermally fuse the edges of the pipe 10. Thereafter, a sheet-shaped tape 30 is wound around the exposed portion of the inner pipe portion 12, the exposed portion of the reinforcing member 14, and a part of the covering member 16 in the pair of connected pipes 10, and is thermally fused. At this time, each fiber 34 of the sheet-like tape 30 is set to be substantially orthogonal to the pipe axis direction of the pipe 10. Thus, in each of the pair of pipes 10, the exposed portion of the inner tube portion 12, the exposed portion of the reinforcing member 14, and a part of the covering member 16 are in a state of being thermally fused to the sheet-shaped tape 30, respectively. Even if the pipe 10 expands and contracts in the pipe axis direction due to heat and pressure, the sheet-shaped tape 30 does not shift from the pipe 10. More specifically, since the inner tube portion 12, the reinforcing member 14, and the covering member 16 are each formed of a thermoplastic resin such as a polyethylene resin, the inner tube portion 12, the reinforcing member 14, and the covering member 16 have a sheet-like shape. When the tape 30 is wound and heat is applied, the inner tube portion 12, the reinforcing member 14, the outer peripheral surface of the covering member 16, and the thermoplastic resin 32 of the sheet-shaped tape 30 are melted, respectively, and the inner tube portion 12 and the reinforcing member 14. The outer peripheral surface of the covering member 16 and the thermoplastic resin 32 of the sheet-shaped tape 30 are thermally fused. For this reason, even if the pipe 10 expands and contracts in the pipe axis direction due to heat and pressure, the inner pipe part 12 is not exposed, and it is possible to prevent the inner pipe part 12 from being broken from this exposed portion. Will be able to do it. When the pipe 10 connected by the butt fusion method is covered with the sheet-shaped tape 30, the outer peripheral surfaces of the inner pipe portion 12, the reinforcing member 14, and the covering member 16, and the thermoplastic resin of the sheet-shaped tape 30 are used. The embodiment is not limited to the mode in which heat sealing is performed by heat-sealing. As another example in the case of covering the pipe 10 connected by the butt fusion method with the sheet-shaped tape 30, the sheet-shaped tape 30 may be thermally fused only to the outer peripheral surface of the inner pipe portion 12, Further, the sheet-shaped tape 30 may be thermally fused only to the outer peripheral surfaces of the inner pipe portion 12 and the reinforcing member 14.

  According to the pipe connection structure 1a, 1b, 1c, 1d, or the pipe connection method of the present embodiment having the above configuration, at least the exposed portion of the inner pipe portion 12 in the pipe 10 is a sheet-shaped tape. 30 at the end of the pipe 10 near a connection point with another pipe 10 so that the fibers 34 of the sheet-shaped tape 30 are in a state of being thermally fused to the pipe 30 and are orthogonal to the pipe axis direction of the pipe 10. Are covered with a sheet-like tape 30. Here, “the exposed portion of the inner pipe portion 12 in the pipe 10 is in a state of being heat-sealed to the sheet-shaped tape 30” means that the inner pipe portion 12 and the sheet-shaped tape 30 are heated. When the surfaces of the tube portion 12 and the sheet-shaped tape 30 are adapted, the state is such that the sheet-shaped tape 30 is attached to the exposed portion of the inner tube portion 12 to the extent of being integrated. In this manner, the plurality of fibers 34 extend in the longitudinal direction, and the fibers 34 are held by the sheet-shaped tape 30 held by the thermoplastic resin 32 in the vicinity of the connection portion with the other pipe 10 at the end of the pipe 10. At this time, at least the exposed portion of the inner pipe portion 12 in the pipe 10 is heat-fused to the sheet-shaped tape 30 and each fiber 34 of the sheet-shaped tape 30 extends in the pipe axis direction of the pipe 10. Since it is made to be substantially perpendicular to the pipe, the pressure-resistant reinforcement at the end of the pipe 10 at a connection point with another pipe 10 can be performed at a low cost and a simple operation, and the pipe 10 expands and contracts in the pipe axis direction. Also, since the sheet-shaped tape 30 is not displaced from the inner tube portion 12, the inner tube portion 12 can be prevented from being exposed.

  In the pipe connection structures 1a, 1b, and 1d, at least a part of the exposed portion of the reinforcing member 14 in the pipe 10 is in a state of being thermally fused to the sheet-shaped tape 30. In this case, the sheet-shaped tape 30 is thermally fused to at least a part of the exposed portion of the reinforcing member 14 so that the sheet-shaped tape 30 can be extended even if the pipe 10 expands and contracts in the pipe axis direction. Since the inner tube portion 12 is not displaced, it is possible to more reliably prevent the inner tube portion 12 from being exposed.

  Further, in the pipe connection structures 1a and 1d, a part of the covering member 16 in the pipe 10 is also in a state of being thermally fused to the sheet-shaped tape 30. In this case, since the sheet-shaped tape 30 is thermally fused to the outer peripheral surface of the covering member 16, the sheet-shaped tape 30 is displaced from the covering member 16 even if the pipe 10 expands and contracts in the tube axis direction. Therefore, the inner tube portion 12 can be more reliably prevented from being exposed.

  In the pipe connection structures 1a, 1b, 1c, 1d, and 2 according to the present embodiment, the reinforcing member 14 is one in which fibers are held by a thermoplastic resin (specifically, for example, aramid tape). Is also good.

  In the pipe connection structures 1a, 1b, 1c, and 1d according to the present embodiment, a part of the exposed portion of the inner pipe portion 12 at the end of the pipe 10 is covered with the joint 20. In this case, the pipe 10 is covered with the sheet-shaped tape 30 at least from the edge of the joint 20. In this case, it is possible to more reliably prevent the inner pipe portion 12 of the pipe 10 from being exposed near the edge of the joint 20.

  In the pipe connection structures 1a, 1b, 1c, and 1d according to the present embodiment, the inner peripheral surface of the joint 20 is attached to the outer peripheral surface of the inner pipe portion 12 of the pipe 10 by electric fusion. That is, an electrofusion (EF) joint is used as the joint 20. Further, in the pipe connection structure 1 d, the sheet-shaped tape 30 is thermally fused to the inner peripheral surface of the joint 20 at a gap between the outer peripheral surface of the inner pipe portion 12 and the inner peripheral surface of the joint 20 in the pipe 10. It is in a worn state. In such a pipe connection structure 1d, a part of the sheet-like tape 30 is firmly adhered to the joint 20 and also firmly adhered to the inner pipe portion 12, the reinforcing member 14, and the covering member 16 of the pipe 10. Therefore, even if the pipe 10 expands and contracts in the pipe axis direction due to heat and pressure, the distance between the joint 20 and the covering member 16 of each pipe 10 can be kept constant, and thus the inner pipe near the end edge of the joint 20 can be maintained. The portion 12 can be more reliably prevented from being exposed. It should be noted that the joint 20 used to connect the pipe 10 is not limited to the above-described electrofusion (EF) joint. As the joint 20 used to connect the pipe 10, various known joints such as a butt fusion joint and a mechanical joint provided around the pipe 10 connected by the butt fusion method may be used. In the case where the sheet-shaped tape 30 according to the present embodiment is used, it is particularly preferable to use an electrofusion (EF) joint when connecting the pipes 10. It becomes possible to reinforce the pressure resistance of the connection point with the cable 10 by an inexpensive and simple operation.

  In addition, according to the sheet-like tape 30 of the present embodiment having the above-described configuration, since the plurality of fibers 34 extending in the longitudinal direction and the thermoplastic resin 32 holding the respective fibers 34 are included, the piping When the pipe 10 is thermally fused to the exposed portion of the inner pipe portion 12 in the pipe 10, it is possible to prevent the sheet-shaped tape 30 from being displaced from the inner pipe portion 12 even if the pipe 10 expands and contracts in the pipe axis direction. .

  In the sheet-like tape 30 according to the present embodiment, a connecting member 36 that connects between the adjacent fibers 34 is provided. As a result, it is possible to maintain the spaces between the adjacent fibers 34 at equal intervals by the connecting member 36, so that the sheet-like tape 30 expands in a direction perpendicular to the direction in which the respective fibers 34 extend by pressure. Can be prevented. In this case, the connection member 36 may extend substantially perpendicularly to the direction in which the fiber 34 extends. Further, the connecting member 36 may be thinner than the fiber 34.

  Further, in the sheet-like tape 30 according to the present embodiment, the size of the fibers 34 and the thermoplastic resin 32 is determined by the size of the pipe 10 and the sheet-like tape 30 when the sheet-like tape 30 is covered with the pipe 10. The ratio of the area occupied by the fibers 34 to the bonding area with the resin is smaller than the ratio of the area occupied by the thermoplastic resin 32 to the bonding area. In this case, the function of reinforcing the connection portion of the pipe 10 by each fiber 34, the function of holding each fiber 34 by the thermoplastic resin 32, and the function of applying heat to the inner pipe portion 12 and the covering member 16 of the pipe 10 by the thermoplastic resin 32. The function of fusing can be sufficiently exhibited.

  In the sheet-like tape 30 according to the present embodiment, the fibers 34 may be aramid fibers. Note that a fiber other than aramid fiber may be used as the fiber 34 as long as it can sufficiently exert the function of reinforcing the connection portion of the pipe 10.

  In the sheet-like tape 30 according to the present embodiment, the fibers 34 may be included in the thermoplastic resin 32. In this case, the function of holding each fiber 34 by the thermoplastic resin 32 can be sufficiently exhibited.

  The pipe connection structure, the pipe connection method, and the sheet-shaped tape according to the present embodiment are not limited to the above-described embodiments, and various changes can be made.

  As a sheet-like tape covering the pipe 10, a material other than that shown in FIG. 9 and the like is used as long as it can be heat-fused at least at the exposed portion of the inner pipe portion 12 in the pipe 10. You may be. For example, a sheet-like tape 30 shown in FIG. 9 from which the connection member 36 is omitted may be used. In the pipe connection structure and the pipe connection method according to the present embodiment, pipes to be connected to other pipes are limited to those including all of the inner pipe portion 12, the reinforcing member 14, and the covering member 16. There is no. In the pipe connection structure and the pipe connection method according to the present embodiment, as pipes to be connected to other pipes, pipes including only the inner pipe portion 12 and the reinforcing member 14 and only the inner pipe portion 12 and the covering member 16 are used. May be used.

DESCRIPTION OF SYMBOLS 1 Piping connection structure 1a, 1b, 1c, 1d before being covered with sheet tape 2 Piping connection structure after being covered with sheet tape 10 Piping 12 Inner pipe portion 14 Reinforcement member 16 Covering member Reference Signs List 20 Joint 22, 24 Electrode 26 Heating wire 30 Sheet tape 32 Thermoplastic resin 34 Fiber 36 Connection member 38 Core 40 Roll

Claims (18)

An inner pipe portion formed of a thermoplastic resin, a reinforcing member wound around the outer peripheral surface of the inner pipe portion, and a pipe having a covering member that covers the reinforcing member;
A sheet-like tape in which a plurality of fibers extend in the longitudinal direction and the fibers are held by a thermoplastic resin,
With
At least the exposed portion of the inner pipe portion in the pipe is in a state of being heat-sealed to the tape, and each fiber of the tape is substantially perpendicular to the pipe axis direction of the pipe, and the end of the pipe is The pipe connection structure in which the vicinity of a connection point with another pipe in the above is covered with the tape.   The pipe connection structure according to claim 1, wherein at least a part of the exposed portion of the reinforcing member in the pipe is in a state of being thermally fused to the tape.   The pipe connection structure according to claim 2, wherein a part of the covering member in the pipe is also thermally fused to the tape.   The pipe connection structure according to any one of claims 1 to 3, wherein the reinforcing member has fibers held by a thermoplastic resin.   The pipe connection structure according to claim 1, wherein a part of an exposed portion of the inner pipe portion at an end of the pipe is covered with a joint.   The pipe connection structure according to claim 5, wherein the pipe is covered with the tape at least from an edge of the joint.   The pipe connection structure according to claim 5, wherein an inner peripheral surface of the joint is attached to an outer peripheral surface of the inner pipe portion of the pipe by electric fusion.   8. The tape is heat-sealed to the inner peripheral surface of the joint at a location of a gap between the outer peripheral surface of the inner pipe portion of the pipe and the inner peripheral surface of the joint. Piping connection structure described. A pipe connection method for connecting a pipe having an inner pipe portion formed of a thermoplastic resin, a reinforcing member wound around the outer peripheral surface of the inner pipe portion, and a coating member covering the reinforcing member to another pipe,
Exposing at least the inner pipe portion in the vicinity of a connection point with another pipe in the pipe,
Connecting the pipe to another pipe,
At least at the exposed portion of the inner pipe portion in the pipe, a plurality of fibers are extended in the longitudinal direction and a sheet-shaped tape in which the fibers are held by a thermoplastic resin is heat-fused. As the fibers are substantially orthogonal to the pipe axis direction of the pipe, a step of coating the tape in the vicinity of a connection point with another pipe at an end of the pipe,
A method of connecting pipes.   The step of coating the tape near an end of the pipe near a connection point with another pipe, wherein the tape is heat-sealed to at least a part of an exposed part of the reinforcing member in the pipe. The piping connection method described.   The step of coating the tape in the vicinity of a connection point with another pipe at an end of the pipe, wherein the tape is thermally fused also to a part of the coating member in the pipe. Connection method. A sheet-like tape for covering the vicinity of a connection point with another pipe in the pipe , which is used in the pipe connection structure according to claim 1 or the pipe connection method according to claim 9 ,
A plurality of longitudinally extending fibers;
A thermoplastic resin holding the fibers,
, A sheet-like tape.   The sheet-like tape according to claim 12, further comprising a connecting member that connects between the adjacent fibers.   14. The sheet-like tape according to claim 13, wherein the connection member extends substantially perpendicular to a direction in which the fibers extend.   The sheet-like tape according to claim 13, wherein the connection member is thinner than the fiber.   The size of the fibers and the thermoplastic resin is such that the ratio of the area occupied by the fibers to the bonding area between the pipe and the tape when the pipe is covered with the tape is the thermoplastic resin to the bonding area. The sheet-like tape according to any one of claims 12 to 15, wherein the size of the sheet-like tape is smaller than a ratio of an area occupied by the tape.   The sheet-shaped tape according to any one of claims 12 to 16, wherein the fiber is an aramid fiber.   The sheet-shaped tape according to any one of claims 12 to 17, wherein the fibers are included in the thermoplastic resin.

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