Piping structure, pipeline, and construction method for piping structure

Abstract

To suppress generation of cracks due to fatigue in a piping structure, to sufficiently prevent damage to the piping structure.SOLUTION: An outer peripheral surface (16p) of an end part of each water supply pipe (16) and an inner peripheral surface (28p) of each socket (28) of a pipe joint (20) are connected with an adhesive (J). An annular buffer member (32) is interposed between the end part of each water supply pipe (16) and each stopper part (30) of the pipe joint (20). An outer peripheral surface (18p) of an end part of a branch pipe (18) and an inner peripheral surface (34p) of each socket (34) of the pipe fitting (20) are connected with the adhesive (J). An annular buffer member (38) is interposed between the end part of the branch pipe (18) and a stopper part (36) of the pipe joint (20).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a piping structure, for example, a pipeline such as a water pipeline, and a construction method for the piping structure. [Background technology]

[0002] As shown in Patent Document 1, a pipeline such as a water pipeline includes a plurality of piping structures, each of which includes a plurality of pipes for transporting water and pipe joints for connecting the plurality of pipes.

[0003] Furthermore, as shown in Patent Document 2, polyvinyl chloride piping and polyvinyl chloride pipe fittings, which have excellent corrosion resistance and workability, are widely used in piping structures. The pipe fittings have multiple sockets for inserting the ends of the pipes, and the inner peripheral surface of each socket is tapered so that the diameter decreases toward the back of the pipe fitting. An annular stopper portion is provided at the back of each socket to regulate the position of the end of each pipe relative to the respective socket. The outer peripheral surface of the end of each pipe and the inner peripheral surface of each socket of the pipe fitting are joined with an adhesive. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-67339 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-278440 Summary of the Invention [Problem to be solved by the invention]

[0005] When inserting the end of a pipe into a pipe fitting's socket, the end face of the pipe's end collides with the pipe fitting's stopper, increasing internal stress in the pipe fitting. Furthermore, when inserting the end of a pipe into the pipe fitting's socket, the adhesive applied to the inner peripheral surface of the pipe fitting's socket is pushed toward the back of the pipe fitting by the corners of the end face of the pipe's end, flowing into the flow path surfaces of the pipe fitting and the pipe, causing solvent cracks on those flow path surfaces. Therefore, fluctuations in water pressure during pipeline operation can cause fatigue cracks in the piping structure, potentially resulting in damage to the piping structure.

[0006] The above-mentioned problems occur not only in piping structures used for service water pipelines, but also in piping structures used for other pipelines such as tap water pipelines.

[0007] Therefore, an object of one aspect of the present invention is to suppress the occurrence of cracks due to fatigue in a piping structure and to sufficiently prevent damage to the piping structure. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, one aspect of the present invention provides a piping structure comprising: a plurality of pipes for transporting water; a plurality of sockets for receiving the ends of the plurality of pipes, the inner circumferential surface of each socket being tapered so that the diameter thereof decreases toward the back; annular stoppers are provided at the back of each socket to regulate the position of the end of each pipe relative to the respective socket; and a pipe fitting for connecting the plurality of pipes. The outer circumferential surface of the end of each pipe and the inner circumferential surface of each socket of the pipe fitting are joined with an adhesive, and annular buffer members are interposed between the end of each pipe and each stopper of the pipe fitting.

[0009] According to the above configuration, as described above, buffer members are interposed between the end of each pipe and the stopper portion of the pipe fitting. Therefore, when the end of each pipe is inserted into the socket of the pipe fitting, the end of each pipe collides with the stopper portion via the buffer member, thereby suppressing an increase in internal stress in the pipe fitting. Furthermore, the buffer members prevent the adhesive applied to the inner peripheral surface of the socket of the pipe fitting from flowing into the flow path surface of the pipe fitting and the flow path surface of the pipe, thereby preventing the occurrence of solvent cracks on those flow path surfaces. This suppresses the occurrence of fatigue-induced cracks in the piping structure and sufficiently prevents damage to the piping structure.

[0010] In the piping structure according to one aspect of the present invention, each buffer member may be attached to an end surface of an end portion of the piping.

[0011] With this configuration, when the ends of the pipes are inserted into the sockets of the pipe joints, the adhesive applied to the inner peripheral surfaces of the sockets of the pipe joints is less likely to be pushed out toward the back of the pipe joints, thereby preventing the adhesive from flowing into the flow passage surfaces of the pipe joints and the pipes.

[0012] In the piping structure according to one aspect of the present invention, each of the buffer members may be formed in a tapered shape.

[0013] With this configuration, when the ends of the pipes are inserted into the sockets of the pipe joints, the adhesive applied to the inner peripheral surfaces of the sockets of the pipe joints is less likely to be pushed out by the inner side of the pipe joints, thereby further preventing the adhesive from flowing into the flow passage surfaces of the pipe joints and the pipes.

[0014] In the piping structure according to one aspect of the present invention, each buffer member may be attached to the stopper portion of the pipe joint.

[0015] With this configuration, even if the adhesive applied to the inner peripheral surfaces of the sockets of the pipe fittings is pushed out toward the back of the pipe fitting when the ends of the pipes are inserted into the sockets of the pipe fittings, the adhesive is blocked by the buffer members, thereby preventing the adhesive from flowing into the flow path surfaces of the pipe fittings and the pipes.

[0016] A pipeline according to one aspect of the present invention is a pipeline for transporting water, and includes a piping structure according to one aspect of the present invention.

[0017] A method for constructing a piping structure according to one aspect of the present invention is a method for constructing a piping structure according to one aspect of the present invention, and includes: an attachment step of attaching each buffer member to an end face of the end of each pipe before inserting the end of each pipe into each receiving port of the pipe fitting; an application step of applying adhesive to the outer surface of the end of each pipe and the inner surface of each receiving port of the pipe fitting before inserting the end of each pipe into each receiving port of the pipe fitting; and a joining step of inserting the end of each pipe into each receiving port of the pipe fitting until each buffer member abuts each stopper portion of the pipe fitting, and joining the outer surface of the end of each pipe to the inner surface of each receiving port of the pipe fitting with adhesive.

[0018] With this configuration, when the ends of the pipes are inserted into the sockets of the pipe joints, the adhesive applied to the inner peripheral surfaces of the sockets of the pipe joints is less likely to be pushed out toward the back of the pipe joints, thereby preventing the adhesive from flowing into the flow passage surfaces of the pipe joints and the pipes.

[0019] A method for constructing a piping structure according to one aspect of the present invention is a method for constructing a piping structure according to one aspect of the present invention, and includes: an attachment step of attaching each buffer member to each stopper portion of the pipe fitting before inserting the end of each pipe into each receiving port of the pipe fitting; an application step of applying adhesive to the outer surface of the end of each pipe and the inner surface of each receiving port of the pipe fitting before inserting the end of each pipe into each receiving port of the pipe fitting; and a joining step of inserting the end of each pipe into each receiving port of the pipe fitting until the end face of the end of each pipe abuts the each buffer member and joining the outer surface of the end of each pipe to the inner surface of each receiving port of the pipe fitting with adhesive.

[0020] With this configuration, even if the adhesive applied to the inner peripheral surfaces of the sockets of the pipe fittings is pushed out toward the back of the pipe fitting when the ends of the pipes are inserted into the sockets of the pipe fittings, the adhesive is blocked by the buffer members, thereby preventing the adhesive from flowing into the flow path surfaces of the pipe fittings and the pipes. [Effects of the Invention]

[0021] According to one aspect of the present invention, it is possible to suppress the occurrence of cracks due to fatigue in the piping structure and sufficiently prevent damage to the piping structure. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic cross-sectional view showing a water pipeline according to an embodiment of the present invention. [Figure 2] FIG. 1 is a schematic plan view showing a water pipeline according to the present embodiment. [Figure 3] FIG. 2 is a schematic cross-sectional view showing a T-shaped piping structure according to the present embodiment. [Figure 4] FIG. 2 is a schematic vertical cross-sectional view showing an L-shaped piping structure according to the present embodiment. [Figure 5] 5A to 5C are schematic cross-sectional views illustrating a construction method for the piping structure according to the present embodiment. [Figure 6] 10A and 10B are schematic cross-sectional views illustrating a construction method for a piping structure according to another aspect of the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0023] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, "U" indicates the upward direction and "D" indicates the downward direction.

[0024] (Overview of 10 water pipelines) An outline of a water pipeline 10 according to this embodiment will be described with reference to Figures 1 and 2. Figure 1 is a schematic cross-sectional view showing the water pipeline 10 according to this embodiment. Figure 2 is a schematic plan view showing the water pipeline 10 according to this embodiment.

[0025] As shown in Figures 1 and 2, the irrigation water pipeline 10 according to this embodiment is a pipeline that supplies irrigation water, which is an example of water, to a farm field F, and is buried underground G. The irrigation water pipeline 10 includes a plurality of T-shaped piping structures 12 and a plurality of L-shaped piping structures 14.

[0026] The T-shaped piping structure 12 includes two water supply pipes 16 for transporting water, one branch pipe 18 for transporting water, and a T-shaped pipe joint 20 that connects the two water supply pipes 16 and the branch pipe 18. The water supply pipes 16, the branch pipe 18, and the pipe joint 20 are each made of a synthetic resin such as polyvinyl chloride.

[0027] The L-shaped piping structure 14 includes one branch pipe 18, one riser pipe 22 for transporting irrigation water, and an L-shaped pipe joint 24 that connects the branch pipe 18 and the riser pipe 22. The riser pipe 22 and the pipe joint 24 are each made of a synthetic resin such as polyvinyl chloride. Furthermore, a water supply valve 26 that controls the supply of irrigation water to the field F is connected to the upper end of each riser pipe 22.

[0028] (Specific configuration of T-shaped piping structure 12) Next, a specific configuration of the T-shaped piping structure 12 will be described with reference to Fig. 3. Fig. 3 is a schematic cross-sectional view showing the T-shaped piping structure 12 according to this embodiment.

[0029] 3, pipe fitting 20, which constitutes part of T-shaped piping structure 12, has two cylindrical tip ends 20a and one cylindrical base end 20b. Pipe fitting 20 has sockets 28 on the two tip end sides 20a, respectively, for inserting the ends of water supply pipes 16. An inner peripheral surface 28p of each socket 28 is tapered so that the diameter decreases toward the back of pipe fitting 20.

[0030] An annular stopper portion (stopper surface) 30 is provided at the rear side of each receiving port 28 to regulate the position of the end of the water supply pipe 16 relative to each receiving port 28. Each stopper portion 30 is tapered so that its diameter decreases toward the rear side of the pipe fitting 20. The taper angle (inclination angle) of each stopper portion 30 relative to the axis of each receiving port 28 is set to be larger than the taper angle of the inner circumferential surface 28p of each receiving port 28 relative to the axis of each receiving port 28. Each stopper portion 30 may be perpendicular to the axis of each receiving port 28.

[0031] The outer peripheral surface 16p of the end of each water supply pipe 16 and the inner peripheral surface 28p of each inlet 28 of the pipe fitting 20 are joined with an adhesive J (see Figures 5 and 6). The solubility value (SP value) of the adhesive J is equivalent to the solubility value of synthetic resins such as polyvinyl chloride.

[0032] An annular buffer member 32 is interposed between the end of each water supply pipe 16 and each stopper portion 30 of the pipe fitting 20. Each buffer member 32 is made of an elastic material such as ethylene propylene rubber. Each buffer member 32 is attached to the end face 16e of the end of each water supply pipe 16 with a volatile adhesive. Each buffer member 32 is formed in a tapered shape and has an annular flange portion 36f that fits inside the water supply pipe 16. Note that instead of attaching each buffer member 32 to the end face 16e of the end of each water supply pipe 16, it may also be attached to the stopper portion 30 of the pipe fitting 20 with a volatile adhesive. The cross-sectional shape of each buffer member 32 may be rectangular, trapezoidal, or any other appropriate shape.

[0033] The pipe fitting 20 has a socket 34 on its base end 20b side for inserting one end (end) of the branch pipe 18. Similar to the inner circumferential surface 28p of the socket 28, the inner circumferential surface 34p of the socket 34 is tapered so that its diameter decreases toward the back of the pipe fitting 20. An annular stopper portion (stopper surface) 36 is provided on the back side of the socket 34 to regulate the position of the one end of the branch pipe 18 relative to the socket 34. Similar to the stopper portion 30, the stopper portion 36 is tapered so that its diameter decreases toward the back of the pipe fitting 20. Note that the stopper portion 36 may be perpendicular to the axis of the socket 34.

[0034] The outer peripheral surface 18p of one end of the branch pipe 18 and the inner peripheral surface 34p of the socket 34 of the pipe fitting 20 are joined with an adhesive J (see FIGS. 5 and 6). An annular buffer member 38 is interposed between one end of the branch pipe 18 and the stopper portion 36 of the pipe fitting 20. Similar to the buffer member 32, the buffer member 38 is made of an elastic material such as ethylene propylene rubber. The buffer member 38 is attached to the end face 18e of one end of the branch pipe 18 with a volatile adhesive. Similar to the buffer member 32, the buffer member 38 has a tapered shape and is formed with an annular flange portion 38f that fits inside the branch pipe 18. Instead of attaching the buffer member 38 to the end face 18e of one end of the branch pipe 18, the buffer member 38 may be attached to the stopper portion 36 of the pipe fitting 20 with a volatile adhesive. The cross-sectional shape of the buffer member 38 may be rectangular, trapezoidal, or any other suitable shape.

[0035] (Specific configuration of L-shaped piping structure 14) Next, a specific configuration of the L-shaped piping structure 14 will be described with reference to Fig. 4. Fig. 4 is a schematic vertical cross-sectional view showing the L-shaped piping structure 14 according to this embodiment.

[0036] 4, pipe fitting 24, which constitutes part of L-shaped piping structure 14, has one cylindrical end portion 24a and another cylindrical end portion 24b. Pipe fitting 24 has a socket 40 on the side of one end portion 24a for inserting the other end portion (end portion) of branch pipe 18. An inner peripheral surface 40p of socket 40 is tapered so that the diameter decreases toward the back side of pipe fitting 24.

[0037] An annular stopper portion 42 is provided at the back side of the socket 40 to regulate the position of the other end of the branch pipe 18 relative to the socket 40. The stopper portion 42 is tapered so that its diameter decreases toward the back side of the pipe fitting 24. The taper angle of the stopper portion 42 relative to the axis of the socket 40 is set to be larger than the taper angle of the inner circumferential surface 40p of the socket 40 relative to the axis of the socket 40. Note that the stopper portion 42 may be perpendicular to the axis of the socket 40.

[0038] The outer peripheral surface 18p of the other end of the branch pipe 18 and the inner peripheral surface 40p of the socket 40 of the pipe fitting 24 are joined with an adhesive J (see FIGS. 5 and 6). An annular buffer member 44 is interposed between the other end of the branch pipe 18 and the stopper portion 42 of the pipe fitting 24. Similar to the buffer member 32, the buffer member 44 is made of an elastic material such as ethylene propylene rubber. The buffer member 44 is attached to the end face 18e of the other end of the branch pipe 18 with a volatile adhesive. Similar to the buffer member 32, the buffer member 44 is tapered and has an annular flange portion 44f that fits inside the branch pipe 18. Instead of attaching the buffer member 44 to the end face 18e of the other end of the branch pipe 18, the buffer member 44 may be attached to the stopper portion 42 of the pipe fitting 24 with a volatile adhesive. The cross-sectional shape of the buffer member 44 may be rectangular, trapezoidal, or any other suitable shape.

[0039] The pipe fitting 24 has a socket 46 on the other end 24b side for inserting the lower end (end) of the rising pipe 22. Similar to the inner circumferential surface 40p of the socket 40, the inner circumferential surface 48p of the socket 46 is tapered so that its diameter decreases toward the back of the pipe fitting 24. Also, an annular stopper portion 48 is provided on the back side of the socket 46 to regulate the position of the lower end of the rising pipe 22 relative to the socket 46. Similar to the stopper portion 42, the stopper portion 48 is tapered so that its diameter decreases toward the back of the pipe fitting 24. Note that the stopper portion 48 may be perpendicular to the axis of the socket 46.

[0040] The outer peripheral surface 22p of the lower end of the riser pipe 22 and the inner peripheral surface 48p of the socket 46 of the pipe fitting 24 are joined with an adhesive J (see FIGS. 5 and 6). An annular buffer member 50 is interposed between the lower end of the riser pipe 22 and the stopper portion 48 of the pipe fitting 24. Similar to the buffer member 32, the buffer member 50 is made of an elastic material such as ethylene propylene rubber. The buffer member 50 is attached to the end surface 22e of the lower end of the riser pipe 22 with a volatile adhesive. Similar to the buffer member 32, the buffer member 50 is tapered and has an annular flange portion 48f that fits inside the riser pipe 22. Instead of attaching the buffer member 50 to the end surface 22e of the lower end of the riser pipe 22, the buffer member 50 may be attached to the stopper portion 48 of the pipe fitting 24 with a volatile adhesive. The cross-sectional shape of the buffer member 50 may be rectangular, trapezoidal, or any other suitable shape.

[0041] (Piping structure construction method) Next, the construction method for the piping structure according to this embodiment will be described with reference to Fig. 5. VA in Fig. 5 is a schematic cross-sectional view illustrating the attachment step and the application step in the construction method for the piping structure according to this embodiment. VB in Fig. 5 is a schematic cross-sectional view illustrating the joining step in the construction method for the piping structure according to this embodiment.

[0042] 5, the first piping structure construction method according to this embodiment is a method for constructing piping structures 12 and 14, and includes an attachment step, an application step, and a joining step. Specific details of each step in the first piping structure construction method are as follows:

[0043] Installation process 5A-V, before inserting the end of each water supply pipe 16 into the corresponding socket 28 of the pipe fitting 20, a buffer member 32 is attached to the end face 16e of the end of each water supply pipe 16 with a volatile adhesive. Also, although not shown, before inserting one end of the branch pipe 18 into the socket 34 of the pipe fitting 20, a buffer member 38 is attached to the end face 18e of one end of the branch pipe 18 with a volatile adhesive.

[0044] Coating process 5A-V, before inserting the end of each water supply pipe 16 into each socket 28 of the pipe fitting 20, adhesive J is applied to the outer peripheral surface 16p of the end of each water supply pipe 16 and the inner peripheral surface 28p of each socket 28 of the pipe fitting 20. Furthermore, although not shown, before inserting one end of the branch pipe 18 into the socket 34 of the pipe fitting 20, adhesive J is applied to the outer peripheral surface 18p of the end of the branch pipe 18 and the inner peripheral surface 34p of each socket 34 of the pipe fitting 20.

[0045] Joining process 5 VB, the end of each water supply pipe 16 is inserted into the corresponding socket 28 of the pipe fitting 20 until each buffer member 32 abuts against the corresponding stopper portion 30 of the pipe fitting 20. This allows the outer peripheral surface 16p of the end of each water supply pipe 16 and the inner peripheral surface 28p of each socket 28 of the pipe fitting 20 to be joined with the adhesive J.

[0046] Furthermore, although not shown, the end of the branch pipe 18 is inserted into the socket 34 of the pipe fitting 20 until the buffer member 38 abuts against the stopper portion 36 of the pipe fitting 20. This allows the outer peripheral surface 18p of one end of the branch pipe 18 and the inner peripheral surface 34p of the socket 34 of the pipe fitting 20 to be joined with the adhesive J.

[0047] As described above, the construction method for a piping structure according to this embodiment can be used to construct the T-shaped piping structure 12. Note that the construction method for a piping structure according to this embodiment can also be used to construct an L-shaped piping structure 14 in the same manner as the construction of the T-shaped piping structure 12.

[0048] (Construction method of piping structure according to other aspects) Next, a construction method for a piping structure according to another aspect of this embodiment will be described with reference to Fig. 6. Line VIA in Fig. 6 is a schematic cross-sectional view illustrating the attachment step and the application step in the construction method for a piping structure according to another aspect of this embodiment. Line VIB in Fig. 6 is a schematic cross-sectional view illustrating the joining step in the construction method for a piping structure according to another aspect of this embodiment.

[0049] The construction method for a piping structure according to another aspect of the present embodiment is a method for constructing the piping structures 12 and 14, and includes an attachment step, an application step, and a joining step. The specific contents of each step in the construction method for a second piping structure are as follows.

[0050] Installation process Before inserting the end of the water supply pipe 16 into each socket 28 of the pipe fitting 20, a buffer member 32 is attached to each stopper portion 30 of the pipe fitting 20 with a volatile adhesive. Also, although not shown, before inserting one end of the branch pipe 18 into the socket 34 of the pipe fitting 20, a buffer member 38 is attached to the stopper portion 36 of the pipe fitting 20 with a volatile adhesive.

[0051] Coating process Before inserting the ends of the water supply pipes 16 into the respective receiving ports 28 of the pipe fittings 20, adhesive J is applied to the outer peripheral surface 16p of the end of each water supply pipe 16 and the inner peripheral surface 28p of each receiving port 28 of each pipe fitting 20. Furthermore, although not shown, before inserting one end of the branch pipe 18 into the receiving port 34 of the pipe fitting 20, adhesive J is applied to the outer peripheral surface 18p of the end of the branch pipe 18 and the inner peripheral surface 34p of each receiving port 34 of the pipe fitting 20.

[0052] Joining process The end of each water supply pipe 16 is inserted into each receiving port 28 of the pipe fitting 20 until the end face 16e of the end of the water supply pipe 16 abuts against each buffer member 32. This allows the outer peripheral surface 16p of the end of each water supply pipe 16 and the inner peripheral surface 28p of each receiving port 28 of the pipe fitting 20 to be joined with the adhesive J.

[0053] Furthermore, although not shown, the end of the branch pipe 18 is inserted into the socket 34 of the pipe fitting 20 until the end face 18e of the end of the branch pipe 18 abuts against the buffer member 38. This allows the outer peripheral surface 18p of one end of the branch pipe 18 and the inner peripheral surface 34p of the socket 34 of the pipe fitting 20 to be joined with the adhesive J.

[0054] As described above, the construction method for a piping structure according to another aspect of this embodiment can be used to construct the T-shaped piping structure 12. Note that, when constructing the L-shaped piping structure 14 using the construction method for a piping structure according to another aspect of this embodiment, the construction is performed in the same manner as when constructing the T-shaped piping structure 12.

[0055] (Action and effect) Next, the effects of this embodiment will be described.

[0056] In the T-shaped piping structure 12, buffer members 32 are interposed between the end of each water supply pipe 16 and each stopper portion 30 of the pipe fitting 20. Therefore, when the end of each water supply pipe 16 is inserted into each receiving port 28 of the pipe fitting 20, the end of each water supply pipe 16 collides with each stopper portion 30 via each buffer member 32, thereby suppressing an increase in internal stress in the pipe fitting 20. Furthermore, each buffer member 32 prevents adhesive J applied to the inner circumferential surface 28p of each receiving port 28 of the pipe fitting 20 from flowing into the flow path surface 20f of the pipe fitting 20 and the flow path surface 16f of the water supply pipe 16, thereby preventing the occurrence of solvent cracks on these flow path surfaces 16f, 20f.

[0057] Here, when each buffer member 32 is attached to the end face 16e of the end of each water supply pipe 16, when the end of each water supply pipe 16 is inserted into each socket 28 of the pipe fitting 20, the adhesive J applied to the inner circumferential surface 28p of each socket 28 of the pipe fitting 20 is less likely to be extruded toward the back of the pipe fitting 20. In particular, because each buffer member 32 is formed in a tapered shape, the adhesive J applied to the inner circumferential surface 28p of each socket 28 of the pipe fitting 20 is less likely to be extruded toward the back of the pipe fitting 20. Furthermore, when each buffer member 32 is attached to each stopper portion 30 of the pipe fitting 20, even if the adhesive applied to the inner circumferential surface of each socket 28 of the pipe fitting 20 is extruded toward the back of the pipe fitting 20 when the end of each water supply pipe 16 is inserted into each socket 28 of the pipe fitting 20, the adhesive is blocked by each buffer member 32.

[0058] In the T-shaped piping structure 12, a buffer member 38 is interposed between one end of the branch pipe 18 and the stopper portion 36 of the pipe fitting 20. Therefore, when one end of the branch pipe 18 is inserted into the socket 34 of the pipe fitting 20, the one end of the branch pipe 18 collides with the stopper portion 36 via the buffer member 38, thereby suppressing an increase in internal stress in the pipe fitting 20. In addition, the buffer member 38 prevents the adhesive applied to the inner circumferential surface 34p of the socket 34 of the pipe fitting 20 from flowing into the flow path surface 20f of the pipe fitting 20 and the flow path surface 18f of the branch pipe 18, thereby preventing solvent cracking on these flow path surfaces 18f, 20f.

[0059] Here, when the buffer member 38 is attached to the end face 18e of one end of the branch pipe 18, when one end of the branch pipe 18 is inserted into the socket 34 of the pipe fitting 20, the adhesive applied to the inner circumferential surface 34p of the socket 34 of the pipe fitting 20 is less likely to be pushed out toward the back of the pipe fitting 20. In particular, because the buffer member 38 is formed in a tapered shape, the adhesive applied to the inner circumferential surface 34p of the socket 34 of the pipe fitting 20 is less likely to be pushed out by the back of the pipe fitting 20 (see FIGS. 5 and 6). Furthermore, when the buffer member 38 is attached to the stopper portion 36 of the pipe fitting 20, even if the adhesive applied to the inner circumferential surface of the socket 34 of the pipe fitting 20 is pushed out toward the back of the pipe fitting 20 when one end of the branch pipe 18 is inserted into the socket 34 of the pipe fitting 20, the buffer member 38 will block the adhesive.

[0060] Therefore, according to this embodiment, it is possible to suppress the occurrence of cracks due to fatigue in the T-shaped piping structure 12, and to sufficiently prevent the T-shaped piping structure 12 from being damaged.

[0061] In the L-shaped piping structure 14, a buffer member 44 is interposed between the other end of the branch pipe 18 and the stopper portion 42 of the pipe joint 24. A buffer member 50 is interposed between the lower end of the rising pipe 22 and the stopper portion 48 of the pipe joint 24. In other words, the L-shaped piping structure 14 has the same configuration as the T-shaped piping structure 12. Therefore, in the piping structure 14, an increase in internal stress in the pipe joint 24 can be suppressed, and solvent cracks can be prevented from occurring on the flow path surfaces 24f, 18f, and 22f of the piping structure 14.

[0062] Therefore, according to this embodiment, it is possible to suppress the occurrence of cracks due to fatigue in the L-shaped piping structure 14, and to sufficiently prevent damage to the L-shaped piping structure 14.

[0063] [Additional Notes] The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in the embodiments are also included in the technical scope of the present invention. [Explanation of symbols]

[0064] 10: water pipeline (pipeline), 12: T-shaped piping structure, 14: L-shaped piping structure, 16: water supply pipe, 16p: outer peripheral surface of end of water supply pipe, 16e: end face of end of water supply pipe, 18: branch pipe, 18p: outer peripheral surface of end (one end, other end) of branch pipe, 18e: end face of end of branch pipe, 20: pipe joint, 20a: tip end (end) of pipe joint, 20b: base end (end) of pipe joint, 22: riser pipe, 22p: outer peripheral surface of bottom end (end) of riser pipe, 22e: end face of bottom end of riser pipe, 24: pipe joint, 24a: one end (end) of pipe joint, 24b: other end (end) of pipe joint, 26: water tap, 28: receptacle, 28p: inner peripheral surface of receptacle, 30: stopper portion (stopper surface), 32: buffer member, 32f: flange portion of buffer member, 34: receptacle, 34p: inner peripheral surface of receptacle, 36: stopper portion (stopper surface), 38: buffer member, 38f: flange portion of buffer member, 40: receptacle, 40p: inner peripheral surface of receptacle, 42: stopper portion (stopper surface), 44: buffer member, 44f: flange portion of buffer member, 46: receptacle, 46p: inner peripheral surface of receptacle, 48: stopper portion (stopper surface), 50: buffer member, 50f: flange portion of buffer member

Claims

1. A plurality of pipes for conveying water; a pipe fitting for connecting a plurality of pipes, the pipe fitting having a plurality of sockets for respectively inserting the ends of the plurality of pipes, the inner circumferential surface of each socket being tapered so that the diameter thereof decreases toward the back, and an annular stopper portion being provided at the back of each socket for regulating the position of the end of each pipe relative to the corresponding socket; The outer peripheral surface of the end of each pipe and the inner peripheral surface of each socket of the pipe joint are joined with an adhesive, An annular buffer member is interposed between the end of each pipe and each stopper portion of the pipe joint, A piping structure characterized in that each buffer member is formed with an annular flange portion that fits inside the piping.

2. 2. The piping structure according to claim 1, wherein each buffer member is attached to an end face of an end portion of each pipe.

3. 3. The piping structure according to claim 2, wherein each of the buffer members is formed in a tapered shape.

4. 2. The piping structure according to claim 1, wherein each buffer member is attached to a corresponding stopper portion of the pipe joint.

5. A pipeline for conveying water, comprising: A pipeline comprising the piping structure according to any one of claims 1 to 4.

6. A method for constructing the piping structure according to claim 1, comprising: an attachment step of attaching each buffer member to an end face of the end of each pipe before inserting the end of each pipe into the corresponding socket of the pipe joint; an application step of applying adhesive to outer peripheral surfaces of the end portions of each of the pipes and inner peripheral surfaces of the sockets of the pipe joints before inserting the end portions of each of the pipes into the sockets of the pipe joints; a joining step of inserting the end of each pipe into each socket of the pipe joint until each buffer member abuts on each stopper portion of the pipe joint, and joining the outer peripheral surface of the end of each pipe to the inner peripheral surface of each socket of the pipe joint with an adhesive.

7. A method for constructing the piping structure according to claim 1, comprising: an attachment step of attaching buffer members to stoppers of the pipe joints before inserting the ends of the pipes into the sockets of the pipe joints; an application step of applying adhesive to outer peripheral surfaces of the end portions of each of the pipes and inner peripheral surfaces of the sockets of the pipe joints before inserting the end portions of each of the pipes into the sockets of the pipe joints; a joining step of inserting the end of each pipe into each socket of the pipe joint until the end face of the end of each pipe abuts each buffer member, and joining the outer peripheral surface of the end of each pipe to the inner peripheral surface of each socket of the pipe joint with an adhesive.

Images