Compression caulking pipe joint

Abstract

To provide a compressively caulked pipe joint capable of certainly detecting construction failure such as forgetting to put a sealing material, by a water pressure test.SOLUTION: A compressively caulked pipe joint caulks a sleeve 50 to a nozzle portion 40 at plural caulking places while inserting one end portion of a resin pipe 70 between the nozzle portion 40 and the sleeve 50, thereby water-tightly press-contacting the resin pipe 70 with the nozzle portion 40 through a seal material 60. The predetermined caulking places include at least a place where the seal material 60 is installed. On an outer peripheral surface of the nozzle portion 40, a circumferential groove 41 in which the seal material 60 is installed, and a water flow groove 49 intersecting the circumferential groove 41 are formed. When the resin pipe 70 is caulked to the nozzle portion 40 without installing the seal material 60, the water flow groove 49 enables water to flow between the nozzle portion 40 and the resin pipe 70.SELECTED DRAWING: Figure 11

Description

Technical Field

[0001] The present invention relates to a compression caulking pipe joint.

Background Art

[0002] As a water supply and hot water supply pipe material piped under a detached house or an apartment building, for example, a resin pipe such as a metal-reinforced polyethylene pipe having a core layer of aluminum and polyethylene resin layers formed on the inner and outer layers sandwiching the core layer is used. The metal-reinforced polyethylene pipe is used, for example, for cold and hot water piping of air conditioning equipment.

[0003] In order to connect a resin pipe such as a metal-reinforced polyethylene pipe and a pipe such as a metal pipe piped outdoors or the like, a compression caulking pipe joint is used. This joint includes a nozzle portion inserted into an end portion of the resin pipe, and by caulking the resin pipe against the nozzle portion, a sealing material between the nozzle portion and the resin pipe is compressed to stop water.

[0004] In the case of this type of pipe joint, even if the resin pipe is not inserted to a predetermined position, if a part of the sealing material and the resin pipe are in contact with each other, water is temporarily stopped and construction defects cannot be detected in a water pressure test. However, the water stopping property may be lost due to long-term pulsation or the like, and there may be a case of water leakage after construction. Therefore, in Patent Document 1, in order to reliably detect construction defects during a water pressure test, a through hole is provided at the bottom of a circumferential groove for a sealing material formed in the nozzle portion, and when the resin pipe is not sufficiently inserted to a predetermined position, a pipe joint is proposed in which water leaks from the through hole.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, the method for detecting construction defects employed in the pipe joint of Patent Document 1 cannot be applied when the resin pipe is caulked not only at the location where the sealing material is installed but also at a location on the base end side of the nozzle portion relative to the location where the sealing material is installed. This is because even if water infiltrates between the resin pipe and the nozzle portion through the through-hole provided at the bottom of the peripheral groove, the resin pipe is press-fitted against the nozzle portion at the caulked portion on the base end side of the nozzle portion, resulting in water stoppage in the short term. Therefore, with the detection method of Patent Document 1, construction defects such as forgetting to install the sealing material or displacement thereof could not be detected during the hydraulic pressure test.

[0007] In view of the above circumstances, an object of the present invention is to provide a compression caulking pipe joint that can surely detect construction defects such as forgetting to install the sealing material or displacement thereof, and the resin pipe not being inserted to a predetermined position, regardless of the position where the resin pipe is caulked with respect to the nozzle portion, by means of a hydraulic pressure test.

Means for Solving the Problems

[0008] In order to achieve the above object, the present invention adopts the following configuration. [1] A nozzle portion inserted into an end portion of a resin pipe to be connected, and a ring-shaped sealing material mounted between the nozzle portion and the resin pipe, A compression caulking pipe joint that caulks the resin pipe at a predetermined caulking location with respect to the nozzle portion with one end portion of the resin pipe externally fitted to the nozzle portion, thereby press-fitting the resin pipe against the nozzle portion in a watertight manner via the sealing material, The predetermined caulking location includes at least the location where the sealing material is mounted, On the outer peripheral surface of the nozzle portion, a peripheral groove where the sealing material is mounted and a water passage groove intersecting with the peripheral groove are formed, The water passage groove has the same depth as the peripheral groove or is shallower than the peripheral groove, A compression caulking pipe joint in which, when the resin pipe is caulked with respect to the nozzle portion without mounting the sealing material, the space between the nozzle portion and the resin pipe is made water-passable by the water passage groove. [2] The compression caulking pipe joint according to [1], wherein the predetermined caulking location further includes a location on the base end side of the nozzle portion from the location where the sealing material is attached. [3] The compression caulking pipe joint according to [1] or [2], wherein the predetermined caulking location further includes a location on the tip end side of the nozzle portion from the location where the sealing material is attached. [4] Further provided with a sleeve surrounding the nozzle portion, With one end of the resin pipe inserted between the nozzle portion and the sleeve, the resin pipe is caulked to the nozzle portion by caulking the sleeve to the nozzle portion at the predetermined caulking location. The compression caulking pipe joint according to any one of [1] to [3]. [5] The compression caulking pipe joint according to any one of [1] to [4], wherein the water passage groove is linearly formed along the axial direction of the nozzle portion on the outer peripheral surface of the nozzle portion. [Effect of the Invention]

[0009] The compression caulking pipe joint of the present invention can surely detect construction defects such as omission or displacement of the sealing material and the resin pipe not being inserted to the predetermined position by a water pressure test, regardless of the position where the resin pipe is caulked to the nozzle portion. [Brief Description of the Drawings]

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Mode for Carrying Out the Invention

[0011] [Compression Caulking Pipe Joint] Hereinafter, a compression caulking pipe joint according to an embodiment of the present invention will be described with reference to the drawings. FIGS. 1 to 3 schematically show a state before a resin pipe 70 is inserted into and caulked to a compression caulking pipe joint 1 according to an embodiment of the present invention. The compression caulking pipe joint 1 shown in FIGS. 1 to 3 includes a joint body 10, a sleeve 50, and a ring-shaped sealing material 60.

[0012] The joint body 10 includes a hexagonal nut-shaped flange portion 20, a cylindrical male screw cylinder portion 30 continuously provided on one side of the flange portion 20, and a cylindrical nozzle portion 40 continuously provided on the other side of the flange portion 20. The joint body 10 is formed of brass, gunmetal, stainless steel, or the like.

[0013] On the nozzle portion 40 side of the flange portion 20, a ring-shaped fitting groove 21 with the male screw cylinder portion 30 side as the bottom is formed. On the circumferential surface of the male screw cylinder portion 30, a male screw for screwing into a member to be connected (for example, a valve box of a valve device), which is not shown in the figure, is formed.

[0014] The nozzle portion 40 has a ring-shaped circumferential groove 41 on the outer circumferential surface at approximately the center in the axial direction, where the sealing material 60 is mounted. Further, a base-end caulking groove 42 is formed on the base-end side (flange portion 20 side) of the nozzle portion 40 with respect to the circumferential groove 41, and a tip-end caulking groove 43 is formed on the tip-end side (opposite side to the flange portion 20) of the nozzle portion 40 with respect to the circumferential groove 41.

[0015] Moreover, the outer circumferential surface of the nozzle portion 40 between the nozzle portion 40 and the base-end caulking groove 42 is a flat portion 44, and the outer circumferential surface of the nozzle portion 40 between the nozzle portion 40 and the tip-end caulking groove 43 is a serrated portion 45. The flange portion 20 side of the base-end caulking groove 42 is a base-end large-diameter portion 46, and the opposite side to the flange portion 20 of the tip-end caulking groove 43 is a tip-end large-diameter portion 47. Furthermore, at two locations in the circumferential groove 41 (two locations facing each other across the central axis of the circumferential groove 41), a water passage groove 49 intersecting the circumferential groove 41 is formed linearly along the axial direction of the nozzle portion 40.

[0016] The outer diameters of the base-end large-diameter portion 46, the flat portion 44, the top of the serrated portion 45, and the tip-end large-diameter portion 47 are all slightly smaller than the inner diameter of the resin tube 70. That is, the heights of the base-end large-diameter portion 46, the flat portion 44, the top of the serrated portion 45, and the tip-end large-diameter portion 47 are all slightly lower than the height of the inner wall of the resin tube 70.

[0017] In the description of the compression caulking pipe joint 1 in this specification, the height means the distance from the central axis of the pipe. The height of the base-end large-diameter portion 46 is set at a position lower than the height where the fitting groove 21 is formed in the flange portion 20. Therefore, a step is formed between the base-end large-diameter portion 46 and the fitting groove 21.

[0018] When the resin tube 70 is inserted, the distance between the bottom surface of the circumferential groove 41 and the inner wall of the resin tube 70 is slightly smaller than the thickness of the sealing material 60 in the non-compressed state (the thickness in the diameter direction of the nozzle portion 40). Further, the groove width of the circumferential groove 41 is slightly wider than the width of the sealing material 60 in the non-compressed state.

[0019] The caulking groove 42 on the base end side and the caulking groove 43 on the tip end side are shallower grooves than the circumferential groove 41. That is, the bottom of the caulking groove 42 on the base end side and the bottom of the caulking groove 43 on the tip end side are positioned higher than the bottom of the circumferential groove 41. The caulking groove 42 on the base end side, the caulking groove 43 on the tip end side, and the serrated portion 45 are substantially the same depth. That is, the bottom of the caulking groove 42 on the base end side, the bottom of the caulking groove 43 on the tip end side, and the bottom of the serrated portion 45 are substantially at the same height.

[0020] The water passage groove 49 is shallower than the circumferential groove 41 and deeper than the height H of the lowest part of the nozzle portion 40 other than the circumferential groove 41. In the present embodiment, the bottom of the water passage groove 49 is at a position higher than the bottom of the circumferential groove 41 and at a position lower than the height H of the lowest part among the bottom of the caulking groove 42 on the base end side, the bottom of the caulking groove 43 on the tip end side, and the bottom of the serrated portion 45.

[0021] Since the water passage groove 49 is shallower than the circumferential groove 41, when the sealing material 60 is properly attached to the nozzle portion 40, the water passage groove 49 is blocked by the sealing material 60 in the circumferential groove 41 portion, and as shown in FIG. 4, the passage of water in the water passage groove 49 is blocked by the sealing material 60. Further, since the water passage groove 49 is deeper than the height H of the lowest part of the nozzle portion 40 other than the circumferential groove 41, when the sealing material 60 is not attached to the nozzle portion 40, as shown in FIG. 5, the water passage groove 49 is not blocked in the middle. Therefore, even when the nozzle portion 40 and the resin tube 70 are in contact with each other by caulking, the water passage groove 49 enables water to pass between the nozzle portion 40 and the resin tube 70.

[0022] The sleeve 50 includes a cylindrical sleeve body 51, a diameter-expanded portion 52 continuously provided at one end of the sleeve body 51 so as to expand in the outer circumferential direction, and a diameter-reduced portion 53 continuously provided at the other end of the sleeve body 51 so as to narrow in the inner circumferential direction. The inner diameter of the sleeve body 51 is substantially the same as or slightly larger than the outer diameter of the resin tube 70.

[0023] The sleeve 50 is arranged with the diameter-reduced portion 53 on the base end side of the nozzle portion 40 and the diameter-expanded portion 52 on the tip end side of the nozzle portion 40 so as to surround the nozzle portion 40. The diameter-reduced portion 53 is fitted and integrated with a fitting groove 21 formed on the nozzle portion 40 side of the flange portion 20. The sleeve 50 is formed of stainless steel, aluminum, or the like.

[0024] The ring-shaped sealing material 60 is formed of a synthetic rubber such as ethylene-propylene-diene copolymer (EPDM). The sealing material 60 is formed so as to elastically deform with a compression rate of 5% to 65% when the resin tube 70 is normally connected to the compression caulking pipe joint 1.

[0025] One end of the resin tube 70 is inserted between the nozzle portion 40 with the sealing material 60 attached and the sleeve 50. With one end of the resin tube 70 inserted, the sleeve 50 is caulked against the nozzle portion 40, whereby the resin tube 70 is caulked against the nozzle portion 40. As a result, the resin tube 70 is watertightly pressed against the nozzle portion 40 via the sealing material 60.

[0026] [Caulking tool] The compression caulking pipe joint 1 of the present embodiment is caulked with the sleeve 50 using a dedicated caulking die 110 shown in FIGS. 7 to 9 mounted on a caulking tool 100 as shown in FIG. 6, for example. As shown in FIGS. 7 to 9, the caulking die 110 is composed of two split dies 110a. The two split dies 110a each have a caulking recess 111 having a substantially semi-cylindrical shape and butting surfaces 112 provided on both sides of the caulking recess 111.

[0027] The two split dies 110a have mating surfaces 112 with a concavo-convex shape in which mating convex surfaces 112a and mating concave surfaces 112b are alternately formed in the axial direction. For the two split dies 110a, the mating convex surface 112a of one split die 110a mates with the mating concave surface 112b of the other split die 110a. On the inner wall surface of the caulking recess 111, three semi-circular caulking ridges 113 are provided in parallel. And the corner portion of the caulking recess 111 including the caulking ridges 113 and the mating surface 112 is chamfered into a curved shape.

[0028] Each caulking ridge 113 is provided so as to reach the corner portion between the inner wall surface of the caulking recess 111 and the mating convex surface 112a along the both end edges of the protrusion 112c forming the mating convex surface 112a and the inner end edge of the end protrusion 112d. In a state where the two split dies 110a are set in the caulking tool 100, the caulking ridges 113 of one split die 110a and the caulking ridges 113 of the other split die 110a are arranged in pairs one by one. In a state where the mating convex surface 112a and the mating concave surface 112b of the two split dies 110a are mated, when each pair of caulking ridges 113 is projected from the direction orthogonal to the axis of the caulking recess 111 (the direction of arrow X in FIG. 8), they are displaced in the axial direction of the caulking recess 111 so as not to overlap in projection, and as shown in FIG. 9, when viewed from the axial direction of the caulking recess 111, both end portions of the paired caulking ridges 113 overlap each other. That is, the paired caulking ridges 113 appear to form a substantially circular shape.

[0029] When caulking is performed using the caulking die 110, caulking can be performed with a light force, and a redundant portion having a wrinkled shape is not formed in the caulked portion, and compression in the circumferential direction does not become uneven. Therefore, the reliability of the joint portion against water leakage and the like is improved. In addition, a sufficient amount of diameter reduction required for the resin tube 70 to be pressed against the nozzle portion 40 can be ensured.

[0030] [Caulking method] Next, a method for connecting the resin tube 70 to the compression caulking pipe joint 1 using the caulking die 110 attached to the caulking tool 100 will be described in detail with reference to FIG. 10. As shown in FIG. 10, one end of the resin tube 70 is inserted between the nozzle portion 40 and the sleeve 50.

[0031] The compression caulking pipe joint 1 into which the resin tube 70 is inserted is placed between the two split dies 110a (only one split die 110a is shown in FIG. 10) such that the nozzle portion 40 is sandwiched, and the three ridges 113 are arranged to contact the sleeve 50 at the seal material caulking portion P1, the base end side caulking portion P2, and the tip end side caulking portion P3, respectively.

[0032] The seal material caulking portion P1 corresponds to the position where the circumferential groove 41 is formed, the base end side caulking portion P2 corresponds to the position where the base end side caulking groove 42 is formed, and the tip end side caulking portion P3 corresponds to the position where the tip end side caulking groove 43 is formed. In this state, when the lever 101 of the caulking tool 100 is operated to move one split die 110a toward the other split die 110a, the seal material caulking portion P1, the base end side caulking portion P2, and the tip end side caulking portion P3 are caulked.

[0033] As a result, as shown in FIG. 11, the seal material 60 attached to the circumferential groove 41 at the seal material caulking portion P1 is compressed. The degree of caulking is preferably such that the seal material 60 is compressed and deformed to a compression ratio of 5% to 65%, and more preferably to a compression ratio of 15% to 25%. Thereby, water is firmly stopped at the seal material 60 portion. Note that the compression ratio is a value obtained by the following formula. Compression ratio = (Seal material height - Compressed seal material height) / Compressed seal material height before compression

[0034] At the caulking portion P2 on the base end side, the resin tube 70 is pressed against the nozzle portion 40 in a state where the inner wall surface side thereof enters the caulking groove 42 portion on the base end side. Also, at the caulking portion P3 on the tip end side, the resin tube 70 is pressed against the nozzle portion 40 in a state where the inner wall surface side thereof enters the caulking groove 43 portion on the tip end side. By pressing the two locations on the inner wall surface side of the resin tube 70 into the grooves formed on the outer peripheral surface of the nozzle portion 40, the resin tube 70 is prevented from coming off.

[0035] On the other hand, as shown in FIG. 12, for example, when the sealing material 60 is forgotten to be inserted, if water cannot be stopped by the sealing material 60, a water leakage path 80 is generated as shown in FIG. 12 and water leaks. The water leakage path 80 is a path that enters the fitting groove 21 from the gap between the large-diameter portion 47 on the tip end side of the nozzle portion 40 and the resin tube 70, passes through the water passage groove 49, and reaches the gap between the large-diameter portion 46 on the base end side of the nozzle portion 40 and the resin tube 70 and extends to the gap between the sleeve 50 and the flange portion 20.

[0036] If there is no water passage groove 49, at the caulking portion P3 on the tip end side, the resin tube 70 is pressed against the bottom of the caulking groove 43 on the tip end side, so temporary water stoppage is possible. However, due to the existence of the water passage groove 49 deeper than the caulking groove 43 on the tip end side, water can also pass through directly below the caulking portion P3 on the tip end side. Similarly, if there is no water passage groove 49, at the caulking portion P2 on the base end side, the resin tube 70 is pressed against the bottom of the caulking groove 42 on the base end side, so temporary water stoppage is possible. However, due to the existence of the water passage groove 49 deeper than the caulking groove 42 on the base end side, water can also pass through directly below the caulking portion P2 on the base end side.

[0037] Also, at the caulking portion P1 of the sealing material, although the resin tube 70 penetrates into the circumferential groove 41 to some extent, it is not caulked so as to penetrate to a position deeper than the bottoms of the caulking groove 42 on the base end side and the caulking groove 43 on the tip end side. Therefore, at least the resin tube 70 is not pressed against the bottom of the circumferential groove 41 and temporary water stoppage is not achieved. Further, although the resin pipe 70 may be in contact with the nozzle portion 40 at the large-diameter portion 47 on the tip side and the large-diameter portion 46 on the base end side, since it is not caulked, water stoppage against water pressure will not occur even temporarily at this location.

[0038] Therefore, according to the compression caulking pipe joint 1, when the sealing material 60 is forgotten to be inserted, it will surely leak during the water pressure test, so the omission of inserting the sealing material 60 can be detected. Similarly, when the sealing material 60 is displaced or the resin pipe 70 is insufficiently inserted, etc., and the water stoppage by the sealing material 60 is not achieved, it will surely leak during the water pressure test, so these construction defects can be detected.

[0039] <Other Embodiments> The present invention is not limited to the above-described embodiments. The compression caulking pipe joint of the present invention connects a plurality of connection targets, but there is no limitation on the connection mode with connection targets other than the resin pipe externally fitted to the nozzle portion in the present invention. For example, instead of the male screw cylinder portion 30 in the above-described embodiment, a pipe joint provided with a female screw member externally fitted and connected to a pipe or the like may be used.

[0040] Further, the outer peripheral surface of the nozzle portion 40 is not particularly limited to other specific shapes as long as the circumferential groove 41 and the water passage groove 49 exist. For example, the flat portion 44 may be serrated like the serrated portion 45. Also, the water passage groove 49 only needs to be shallower than the circumferential groove 41, and is not limited to a groove shallower than the circumferential groove 41 as in the above-described embodiment, and may be a groove having the same depth as the circumferential groove 41. Also, the water passage groove 49 is not limited to a mode formed in a straight line along the axis, and may be formed, for example, in a spiral shape.

[0041] Further, if caulking ridges are formed at positions corresponding to the caulking portion of the sealing material P1, the caulking portion P2 on the base end side, and the caulking portion P3 on the tip end side inside the sleeve 50, instead of using the caulking tool 100 having the caulking die 110 with the caulking ridges 113 formed thereon, caulking may be performed using a caulking tool that caulks the whole uniformly. Further, the sleeve 50 may be caulked using a caulking member that is externally fitted to the sleeve 50. Further, without using the sleeve 50, caulking may be performed using a fastener that directly caulks each of the caulking portion of the sealing material P1, the caulking portion P2 on the base end side, and the caulking portion P3 on the tip end side individually.

[0042] Further, the predetermined caulking positions are not limited to the three positions of the caulking portion of the sealing material P1, the caulking portion P2 on the base end side, and the caulking portion P3 on the tip end side in the above-described embodiment, and for example, only the caulking portion of the sealing material P1 may be used. Further, it may be two positions of the caulking portion of the sealing material P1 and the caulking portion P2 on the base end side or the caulking portion P3 on the tip end side. Further, it may be four or more positions including the caulking portion of the sealing material P1.

Explanation of Signs

[0043] 1 Compression caulking pipe joint 10 Joint body 20 Flange portion 21 Fitting groove 30 Male screw cylinder portion 40 Nozzle portion 41 Circumferential groove 42 Caulking groove on the base end side 43 Caulking groove on the tip end side 49 Water passage groove 50 Sleeve 60 Sealing material 70 Resin pipe 80 Leakage path P1 Caulking portion of the sealing material P2 Caulking portion on the base end side P3 Caulking portion on the tip end side

Claims

1. A nozzle portion inserted into an end portion of a resin tube to be connected, and an annular sealing material mounted between the nozzle portion and the resin tube, wherein the resin tube is caulked to the nozzle portion at a predetermined caulking location with one end portion of the resin tube externally fitted to the nozzle portion, so that the resin tube is hermetically pressed against the nozzle portion via the sealing material, and the compression caulking pipe joint is provided, wherein the predetermined caulking location includes at least a location where the sealing material is mounted, wherein a circumferential groove for mounting the sealing material is formed on an outer peripheral surface of the nozzle portion, and a water passage groove intersecting the circumferential groove is linearly formed along an axial direction of the nozzle portion, wherein the water passage groove has the same depth as the circumferential groove or is shallower than the circumferential groove, and when the resin tube is caulked to the nozzle portion without mounting the sealing material, a space between the nozzle portion and the resin tube is made water-permeable by the water passage groove, and the compression caulking pipe joint is provided.

2. The compression caulking pipe joint according to claim 1, wherein the predetermined caulking location further includes a location on a proximal end side of the nozzle portion with respect to a location where the sealing material is mounted.

3. The compression caulking pipe joint according to claim 1 or 2, wherein the predetermined caulking location further includes a location on a distal end side of the nozzle portion with respect to a location where the sealing material is mounted.

4. Furthermore, a sleeve surrounding the nozzle portion is provided, and with one end portion of the resin tube inserted between the nozzle portion and the sleeve, the sleeve is caulked to the nozzle portion at the predetermined caulking location, so that the resin tube is caulked to the nozzle portion, and the compression caulking pipe joint according to any one of claims 1 to 3 is provided.

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