Pipe joint and pipe connection method

Abstract

To eliminate limitations on an internal diameter dimension imposed due to increase in a thickness of an in-core and prevent a worker from forgetting to install the in-core.SOLUTION: A pipe joint includes: a joint body 101; a nut 107 attached to an end of the joint body 101; a seal member 102 which comes into contact with an outer peripheral surface of a pipe P disposed at the inner side of the joint body 101; and a resin in-core 106 supporting the pipe P from the inner side. The in-core 106 has: a cylinder part 108 disposed at the inner side of the pipe P; and a flange part 110a which is provided on an outer peripheral surface of an end of the cylinder part 108 and comes into contact with an end surface in an axial direction of the pipe P. A groove 111 which houses the flange part 110a is formed on an inner peripheral surface of the joint body 101.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a pipe joint structure and a method for connecting a pipe to the pipe joint. [Background technology]

[0002] Conventionally, pipe joints are used in buildings such as detached houses, condominiums, and commercial facilities to connect piping for water supply, hot water supply, or air conditioning equipment. As such pipe joints, a joint structure is known in which a seal member is housed inside a housing groove provided on the inner peripheral surface of the joint body, and the seal member abuts against the outer surface of a pipe inserted inside the joint body to stop water. Such pipe joints are equipped with an in-core to prevent the pipe from deforming inward.

[0003] As shown in the following Patent Document 1, the incore is composed of a cylindrical tube portion and an annular flange portion formed to protrude from one end side of the tube portion. By making the length of the incore the same as the insertion depth of the pipe into the pipe joint, the worker can visually check the inner end of the incore through the pipe from the outside when the entire incore together with the pipe is inserted into the pipe joint. Therefore, it is possible to prevent the pipe from being inserted into the joint to an insufficient depth. Such an incore is shipped separately from the pipe fitting. Therefore, there is a problem that the worker forgets to attach the incore when inserting the pipe, and water leakage occurs due to insufficient insertion, etc. To solve this problem, a pipe fitting in which the pipe fitting and the incore are integrated is disclosed as shown in the following Patent Document 2. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2004-68923 A [Patent Document 2] JP 2008-25659 A [Patent Document 3] JP 2016-223469 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the case of pipe fittings where flow rate is required, it is desirable to make the inner core, which is the part that comes into contact with water, thinner and larger in inner diameter. Incidentally, when a pipe joint in which a pipe joint and an incore are integrated as described above is injection molded, a manufacturing method such as that shown in the above-mentioned Patent Document 3 is disclosed. In this method, after filling the cavity of a mold with molten resin to mold an incore, the mold is opened and a core pin is extracted from the inner peripheral surface of the incore to mold the incore. Here, the incore needs to be supported by contacting the inner peripheral surface of the pipe, and is designed to have the same length as the receiving port of the joint. Therefore, the core pin extracted from the inner peripheral surface of the incore when the mold is opened becomes long. As a result, molding defects such as deformation of the incore when the core pin is extracted from the inner peripheral surface of the incore are likely to occur. Therefore, a certain wall thickness is required to prevent the incore from being deformed. Therefore, the inner diameter dimension of the incore is restricted, and although a thin wall is desired from the functional aspect as described above, the above-mentioned manufacturing method makes it difficult to make the wall thin from the manufacturing aspect.

[0006] The present invention aims to provide an incore assembly method and a pipe joint that solve the inner diameter dimension restrictions caused by thickening of the incore in an integral incore joint and the problem of forgetting to install the incore when the incore is separate. [Means for solving the problem]

[0007] A pipe fitting according to one embodiment of the present invention comprises a fitting body, a nut attached to an end of the fitting body, a sealing member in contact with an outer peripheral surface of a pipe placed inside the fitting body, and a resin incore supporting the pipe from the inside, the incore having a tubular portion placed inside the pipe, and a flange portion provided on the outer peripheral surface of the end of the tubular portion and in contact with the axial end face of the pipe, and a groove for accommodating the flange portion is formed on the inner peripheral surface of the fitting body. Effect of the Invention

[0008] The pipe joint of the present invention can solve the problem of inner diameter dimensions being restricted by thickening of the incore of an integral incore joint, as well as the problem of forgetting to forget the incore during installation when the incore is separate. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view showing a pipe joint according to an embodiment of the present invention. [Diagram 2] FIG. 11 is a cross-sectional view showing a pipe joint according to a modified example of an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a pipe joint according to one embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view showing a state in which a pipe P is inserted into a pipe fitting 100 according to an embodiment of the present invention. Here, the axis is a line passing perpendicularly through the center of a horizontal plane perpendicular to the extension direction of the pipe fitting 100, and the radial direction is a direction perpendicular to the axis. The pipe fitting 100 has an axisymmetric shape with respect to the axis as an axis, and also has a plane-symmetric shape with a horizontal plane perpendicular to the axis at the center of the pipe fitting 100 in the axial direction as a symmetry plane.

[0011] A pipe fitting 100 according to one embodiment of the present invention is a member for connecting a plurality of pipes (piping) P for water supply, hot water supply, or air conditioning equipment in a building. The pipe fitting 100 and the pipe P connected to this pipe fitting 100 constitute a piping structure. The pipe P is, for example, a polyolefin pipe for water supply. The pipe joint 100 includes a joint body 101, a seal member 102, a base 103, a stop ring 104, a spacer 105, an inner core 106, and a nut 107. The inner core 106 is made of resin, but may be made of metal, and there is no restriction on the material. The joint body 101 and the nut 107 may also be made of resin, or may be made of metal, and there is no restriction on the material.

[0012] The joint body 101 is formed in a hollow cylindrical shape extending in the axial direction, and both axial ends are open. The outer diameter and the inner diameter are reduced in the axial central portion of the joint body 101. A male thread is formed on the outer peripheral surface outside the axial center of the joint body 101. The male thread is screwed into a female thread formed on the nut 107. The joint body 101 is formed so that its inner diameter increases from the central portion in the axial direction of the joint body 101 toward the outside. The inner peripheral surface of the joint body 101 has a multi-step shape.

[0013] The inner circumferential surface of the joint body 101 includes a first inner circumferential surface 101a, a second inner circumferential surface 101b, a third inner circumferential surface 101c, a fourth inner circumferential surface 101d, and a fifth inner circumferential surface 101e. Among these inner circumferential surfaces, the first inner circumferential surface 101a, the second inner circumferential surface 101b, and the fourth inner circumferential surface 101d face inward in the radial direction. The fourth inner circumferential surface 101d, the first inner circumferential surface 101a, and the second inner circumferential surface 101b are arranged in this order from the inside to the outside in the axial direction. The fourth inner circumferential surface 101d, the first inner circumferential surface 101a, and the second inner circumferential surface 101b have larger diameters in this order. The third inner circumferential surface 101c and the fifth inner circumferential surface 101e face outward in the axial direction. The third inner circumferential surface 101c forms a step connecting the first inner circumferential surface 101a and the second inner circumferential surface 101b. The fifth inner circumferential surface 101e forms a step connecting the fourth inner circumferential surface 101d and the second inner circumferential surface 101b.

[0014] The fourth inner circumferential surface 101d is located at the center portion of the joint body 101 in the axial direction. The fifth inner circumferential surface 101e is provided with a recess 112. The recess 112 is disposed on the inner circumferential edge of the fifth inner circumferential surface 101e. The recess 112 is provided at a connecting portion between the fifth inner circumferential surface 101e and the fourth inner circumferential surface 101d. The recess 112 is recessed inward in the axial direction from the fifth inner circumferential surface 101e. The recess 112 is provided around the entire circumference in the circumferential direction. The recess 112 is annular.

[0015] The recess 112 includes an inner peripheral surface that is L-shaped in cross section and a space extending in the axial direction at an axis line corresponding to the inner peripheral surface. The inner peripheral surface has a horizontal surface (also called an end surface) perpendicular to the axial direction and a surface extending in the axial direction. The recess 112 may be omitted.

[0016] The first inner circumferential surface 101a is provided with a groove 111. The groove 111 will be described in detail later. A portion of the first inner circumferential surface 101a located between the third inner circumferential surface 101c and the groove 111 is in close contact with the pipe P. A seal member 102 is disposed on the third inner circumferential surface 101c. The second inner peripheral surface 101b is located on the outside in the axial direction relative to the first inner peripheral surface 101a, and has a larger diameter than the first inner peripheral surface 101a. Furthermore, a base 103, a stop ring 104, and a spacer 105 are arranged on the second inner peripheral surface 101b. Two stop rings 104 are provided with an interval in the axial direction. The stop rings 104 prevent the pipe P arranged in the joint body 101 from coming off. Of the two stop rings 104, the stop ring 104 located on the inside in the axial direction is arranged on the base 103. A spacer 105 is arranged between the two stop rings 104.

[0017] The joint body 101 and the nut 107 constitute an incore accommodating portion 113. The incore accommodating portion 113 is a space that accommodates the incore 106. The incore accommodating portion 113 is a space that is located outside the fourth inner peripheral surface 101d (recess 112) in the axial direction, among the spaces formed by the joint body 101 and the nut 107. At approximately the center in the axial direction of the incore accommodating portion 113, there is a portion with an expanded diameter in order to accommodate the seal member 102, the base 103, the stop ring 104, and the spacer 105. When the pipe P is inserted into the pipe joint 100, the seal member 102, the base 103, the stop ring 104, and the spacer 105 surround the pipe P so as to be in close contact with the pipe P. The second inner peripheral surface 101b is formed in the expanded diameter portion of the incore accommodating portion 113.

[0018] The inner circumferential surface of the nut 107 may be formed so as to narrow from the outside toward the inside in the axial direction. In this case, the inner core 106 can be easily inserted into the nut 107 from the flange portion 110a when connecting pipes. Alternatively, the pipe P can be easily inserted into the nut 107.

[0019] The groove 111 is formed on the first inner peripheral surface 101a and accommodates the flange portion 110a. The groove 111 is disposed on the inner side in the axial direction with respect to the center in the axial direction of the first inner peripheral surface 101a. The groove 111 is disposed on the outer side in the axial direction with respect to the inner end in the axial direction of the first inner peripheral surface 101a. The inner diameter of the end face of the groove 111 facing radially outward is larger than the inner diameter of the first inner peripheral surface 101a and smaller than the inner diameter of the second inner peripheral surface 101b. Furthermore, the outer diameter of the flange portion 110a is larger than the inner diameter of the first inner peripheral surface 101a. Therefore, since the flange portion 110a is engaged with the groove 111, when the flange portion 110a is accommodated in the groove 111, the in-core 106 does not easily come out of the joint body 101. As will be described later, groove 111 locks flange portion 110a so that it will not easily come off even if an attempt is made to pull it out in the axial direction.

[0020] The inner core 106 is formed in a hollow cylindrical shape extending in the axial direction, and both ends in the axial direction are open. The inner core 106 has a cylindrical portion 108 and a flange portion 110a.

[0021] The outer diameter of the tubular portion 108 is smaller than the inner diameter of the in-core accommodating portion 113. The tubular portion 108 can be accommodated in the in-core accommodating portion 113. The tubular portion 108 has a first end portion 109 and a second end portion 110. The first end portion 109 is one end portion of the tubular portion 108 in the axial direction. The second end portion 110 is provided with a flange portion 110a. When the pipe P is connected, the tubular portion 108 is disposed inside the pipe P. Therefore, the in-core 106 supports the pipe P from the inside. The pipe P is inserted into the in-core 106 in the axial direction from the first end portion 109 side. When the tubular portion 108 is located inside the pipe P, the pipe P is in close contact with the tubular portion 108, and the tubular portion 108 is surrounded by the pipe P.

[0022] When connecting a pipe P as shown in FIG. 1, the first end portion 109 is inserted so as to be positioned outside the joint body 101 in the axial direction. On the other hand, although not shown, when the pipe fitting 100 is stored, the first end 109 is inserted so as to be located inside the fitting body 101 in the axial direction. The inner diameter of the first end 109 is larger than the inner diameter of the fourth inner circumferential surface 101d (the central portion of the fitting body 101 in the axial direction) and smaller than the inner diameter of the recess 112. As a result, during the insertion as described above, the first end 109 is positioned in the recess 112.

[0023] As shown in Fig. 1, the flange 110a is a flange formed to protrude radially outward from the tubular portion 108 in the circumferential direction. The outer diameter of the flange 110a is smaller than the inner diameter of the groove 111. When connecting a pipe P as shown in Fig. 1, the flange 110a is inserted so as to be housed in the groove 111 of the joint body 101, and comes into contact with the end face of the pipe P in the axial direction. On the other hand, although not shown, when the pipe fitting 100 is stored, the flange 110a may be inserted so as to be located on the outside in the axial direction of the fitting body 101. In this case, it is preferable that the flange 110a does not protrude axially outward from the in-core accommodating portion 113 (nut 107). Note that, when the pipe P is connected as shown in FIG. 1, even if the flange 110a is located on the inside in the axial direction, the flange 110a is not disposed in the recess 112. At this time, the flange 110a is disposed in the groove 111, and the second end 110 abuts against the inner peripheral surface (the surface serving as a stopper) on the inside in the axial direction of the groove 111.

[0024] The radially outer end face of flange 110a may be formed so that the diameter of in-core 106 decreases toward the inside in the axial direction when connecting pipe P. This decrease in diameter makes it easier to insert in-core 106 into fitting body 101 from flange 110a when connecting pipes.

[0025] 2, in a pipe fitting 100A according to a modified example of the present invention, a portion of the first inner circumferential surface 101a of the fitting body 101 that is located between the third inner circumferential surface 101c and the groove in the axial direction tapers in diameter from the third inner circumferential surface 101c toward the groove. Hereinafter, the portion that is tapered in diameter is referred to as a taper 114. Furthermore, when the angle between the third inner circumferential surface 101c and the taper 114 is α, 0°<α<90°. Furthermore, the reduced diameter makes it easier to insert the in-core 106 into the pipe. When the radially outer end face of the flange 110a is formed to be reduced in diameter, the angle between the inner circumferential surface located on the axially inner side facing the axially outer side of the flange 110a and the reduced-diameter radially outer end face may be the same as α, or may be larger than α, or may be smaller than α. Furthermore, the axial length of the taper 114 may be 6.0 mm or less. Not limited to the embodiment shown in Fig. 2, the length of a portion of the first inner circumferential surface 101a of the joint body 101 located between the third inner circumferential surface 101c and the groove in the axial direction may be 6.0 mm or less.

[0026] (Pipe connection method) Next, a method for connecting the pipes P according to one embodiment of the present invention will be described. In this connection method, with the flange portion 110a housed in the groove and the incore 106 disposed within the joint body, the pipe P is inserted between the inner peripheral surface of the joint body 101 and the outer peripheral surface of the tubular portion. That is, in this connection method, the incore 106 (tubular portion) is not inserted into the end of the pipe P and then the pipe P is inserted into the pipe joint, but rather the pipe P is inserted into the pipe joint with the incore 106 attached to the joint body 101. Here, the inner core 106 may be pre-assembled to the joint body 101 during storage. That is, the first end 109 of the cylindrical portion 108 may be located axially outward from the second end 110, and the flange portion 110a may be disposed in the groove. On the other hand, the incore 106 is not assembled to the joint body 101 during storage, and an installer may assemble the incore 106 to the joint body 101 before inserting the pipe P. In this case, during storage, the second end 110 of the tubular portion 108 is located axially outward of the first end 109, and the first end 109 is accommodated in the recess 112. After removing the incore 106 from the incore accommodating portion 113, the installer reverses the orientation of the incore 106 in the axial direction and accommodates the flange portion 110a in the groove 111.

[0027] According to the above method, when the pipe fitting 100 is stored, the in-core 106 can be stored inside the fitting body 101. Furthermore, the time and effort required to remove the in-core 106 from the fitting body 101 and insert it into the pipe P during installation can be eliminated.

[0028] (Flow rate measurement results) The following table shows the flow rate (L / m) per unit time experimentally measured in a pipe in which 20 φ13 elbow joints, each with a total length of 5 m, are connected to each pipe (pipe P) with a total length of 15 m. An elbow joint according to one embodiment of the present invention was used as Example 1, and an Onda double lock joint (registered trademark) elbow joint was used as Comparative Example 1. The Comparative Example is a so-called in-core integrated type joint. The in-core inner diameter of each joint was 10.75 mm for the joint in Example 1, and 9.50 mm for the joint in Comparative Example 1. The flow rate was measured three times for each of the joints in Example 1 and Comparative Example 1, and the average value of the three measurements was calculated, with each measurement being designated as Measurement 1 to Measurement 3. The results of Measurements 1 to 3 were calculated from the actual weight (volume) of the fluid and the time, but the upper and lower limits of the measurement results of the flowmeter installed in the pipe are also listed as reference values.

[0029] [Table 1]

[0030] Comparing the average flow rates of Example 1 and Comparative Example 1, the average flow rate of Example 1 was higher than the average flow rate of Comparative Example 1. This is believed to be because the in-core inner diameter of Example 1 was larger than that of Comparative Example 1, and the flow path diameter of the fitting was enlarged, resulting in an increase in the flow rate per unit time. From the above results, it can be seen that even in a separately molded fitting, it is possible to increase the flow path diameter by enlarging the in-core inner diameter, thereby increasing the flow rate per unit length.

[0031] According to the pipe fitting 100 of the embodiment described above, as shown in FIG. 1, a groove 111 for accommodating the flange portion 110a is formed on the inner peripheral surface of the fitting body 101. The above configuration allows the flange portion 110a of the incore 106 to be accommodated in the groove 111, and the incore 106 does not come off from the fitting body 101 after fitting. Therefore, although the fitting body 101 and the incore 106 are molded separately, it is possible to prevent the incore from being forgotten during construction, for example, as in the case of an integral incore. In addition, for example, by forming the fitting body 101 and the incore 106 separately, there is no molding restriction as in the case of an integral incore. In this way, molding stability and molding freedom are improved, and for example, the incore 106 can be easily thinned. Furthermore, by thinning the in-core 106, the flow passage diameter is enlarged, thereby improving the flow rate. Furthermore, by thinning the inner core 106, a sufficient gap can be secured for removing the core pin from the inner peripheral surface of the inner core 106. Therefore, a sufficient draft angle can be secured, and injection molding can be facilitated. In addition, since the in-core 106 is made of resin, the in-core 106 can be easily inserted into the joint body 101 due to the deformability of the resin.

[0032] Furthermore, the inner circumferential surface of the joint body 101 is provided with a first inner circumferential surface 101a having a diameter smaller than the outer diameter of the flange portion 110a. This makes it possible to further prevent the incore 106 from coming off the joint body 101 after the flange portion 110a of the incore 106 is housed in the groove 111. This makes it possible to more reliably prevent, for example, the incore from being forgotten during installation when the incore is a separate piece.

[0033] Moreover, the portion located between the third inner circumferential surface 101c and the groove 111 has a reduced diameter from the third inner circumferential surface 101c toward the groove 111. Due to the reduced diameter, the inner core 106 having the flange portion 110a can be easily inserted into the joint body 101.

[0034] Furthermore, when the length of the portion of the first inner circumferential surface 101a located between the third inner circumferential surface 101c and the groove 111 in the axial direction is set to 6.0 mm or less, the length of the third inner circumferential surface 101c and the groove 111 in the axial direction can be shortened. In other words, the pipe fitting 100 can be made more compact, and costs can be reduced.

[0035] Furthermore, when the joint body 101, the nut 107, and the inner core 106 are each formed from resin, it is possible to reduce the weight of the pipe joint 100. Furthermore, even if a highly corrosive fluid flows inside the joint body (flow path), it is possible to prevent the pipe joint from corroding and the fluid from leaking.

[0036] Furthermore, when the joint body 101 and the nut 107 are each made of metal, the strength of the pipe joint 100 can be increased.

[0037] The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0038] The number of stop rings 104 may be one, or three or more. The base 103, the stop ring 104, and the spacer 105 may be omitted.

[0039] In addition, within the scope of the invention, the components in the above-described embodiments may be replaced with well-known components, and the above-described modified examples may be combined as appropriate.

[0040] (Additional Note) <1> A pipe fitting according to one embodiment of the present invention comprises a fitting body, a nut attached to an end of the fitting body, a sealing member in contact with an outer peripheral surface of a pipe placed inside the fitting body, and a resin incore supporting the pipe from the inside, the incore having a tubular portion placed inside the pipe, and a flange portion provided on the outer peripheral surface of the end of the tubular portion and in contact with the axial end face of the pipe, and a groove for accommodating the flange portion is formed on the inner peripheral surface of the fitting body.

[0041] According to the above pipe joint, a groove for accommodating the flange is formed on the inner peripheral surface of the joint body. The above configuration allows the flange of the incore to be accommodated in the groove, and the incore does not come out of the joint body after the flange of the incore is accommodated in the groove. Therefore, although the joint body and the incore are molded separately, it is possible to prevent the incore from being forgotten during installation, for example, as with the incore integrated type. Furthermore, for example, by forming the joint body and the incore separately, there are no molding restrictions as with the incore integrated type. Therefore, molding stability and molding freedom are improved, and for example, it is possible to easily reduce the thickness of the incore. Furthermore, by thinning the in-core, the flow passage diameter is enlarged, thereby improving the flow rate. Furthermore, by thinning the inner core, a sufficient gap for removing the core pin from the inner peripheral surface of the inner core can be secured, so that a sufficient draft angle can be secured and injection molding can be facilitated. Furthermore, since the incore is made of resin, the deformability of the resin allows the incore to be easily inserted into the joint body.

[0042] <2> the above <1> In the pipe fitting according to the above, the inner circumferential surface of the fitting body may include a first inner circumferential surface having a diameter smaller than an outer diameter of the flange portion, a second inner circumferential surface located axially outward from the first inner circumferential surface and having a diameter larger than the first inner circumferential surface, and a third inner circumferential surface forming a step connecting the first inner circumferential surface and the second inner circumferential surface, facing axially outward, and in which the seal member is disposed, and the groove may be formed in the first inner circumferential surface.

[0043] According to the above pipe joint, the inner circumferential surface of the joint body is provided with a first inner circumferential surface having a diameter smaller than the outer diameter of the flange. This configuration can further prevent the incore from coming off the joint body after the flange of the incore is housed in the groove. Therefore, for example, it is possible to more firmly prevent the incore from being forgotten during installation when the incore is a separate body.

[0044] <3> the above <2> In the pipe fitting according to the present invention, a configuration may be adopted in which a portion of the first inner circumferential surface that is located between the third inner circumferential surface and the groove in the axial direction has a diameter that decreases from the third inner circumferential surface toward the groove.

[0045] According to the above pipe joint, the portion located between the third inner circumferential surface and the groove is tapered in diameter from the third inner circumferential surface toward the groove. Due to the tapered diameter, the inner core having the flange portion can be easily inserted into the joint body.

[0046] <4> the above <2> or <3> The pipe fitting according to the present invention may employ a configuration in which a portion of the first inner circumferential surface that is located between the third inner circumferential surface and the groove in the axial direction has a length of 6.0 mm or less.

[0047] According to the above pipe joint, the length of the third inner peripheral surface and the groove in the axial direction can be shortened. Also, the axial length that the flange needs to overcome from the third inner peripheral surface to the groove can be shortened. Therefore, the in-core having the flange portion can be easily inserted into the joint body. Furthermore, the above configuration allows the pipe joint to be made compact, which is expected to reduce costs.

[0048] <5> the above <1> from <4> In the pipe joint according to any one of the above aspects, each of the joint body, the nut, and the in-core may be made of resin.

[0049] According to the above pipe joint, the joint body, the nut, and the core are each formed of resin. This configuration allows the weight of the pipe joint to be reduced. Furthermore, even if a highly corrosive fluid flows through the joint body (flow path), the pipe joint can be prevented from corroding and the fluid can be prevented from leaking.

[0050] <6> the above <1> from <4> In the pipe joint according to any one of the above aspects, the joint body and the nut may be made of metal.

[0051] According to the above pipe joint, the joint body and the nut are each made of metal. With this configuration, the strength of the pipe joint can be increased.

[0052] <7> the above <1> from <6> In the pipe connecting method according to any one of the above, the flange portion is housed in the groove and the incore is disposed in the joint body, and then the pipe is inserted between the inner peripheral surface of the joint body and the outer peripheral surface of the tubular portion. That is, in this connecting method, the incore (tubular portion) is inserted into the end of the pipe P, and then the pipe is inserted into the pipe joint, but rather, the pipe is inserted into the pipe joint with the incore attached to the joint body. Here, the in-core may be pre-assembled to the joint body during storage. That is, the first end of the cylindrical portion may be located axially outward relative to the second end, and the flange portion may be disposed in the groove. On the other hand, the incore is not attached to the fitting body during storage, and an installer may assemble the incore to the fitting body before inserting the pipe. In this case, during storage, the second end of the tubular portion is located axially outward from the first end, and the first end is housed in the recess. After removing the incore from the incore housing portion, the installer reverses the orientation of the incore in the axial direction and houses the flange portion in the groove.

[0053] According to the above method, the incore can be stored inside the joint body when the pipe joint is stored. Furthermore, the time required for removing the incore from the joint body and inserting it into the pipe during installation can be eliminated. [Explanation of symbols]

[0054] 100 Pipe fittings 101 Fitting body 101a First inner surface 101b Second inner peripheral surface 101c 3rd inner surface 101d 4th inner surface 101e 5th inner surface 102 Sealing material 103 Base 104 Stop ring 105 Spacer 106 Incore 107 Nut 108 Cylinder part 109 First end 110 Second end 110a Tsuba 111 Groove 112 Recess 113 Incore Storage Unit P-Pipe

Claims

1. A joint body, A nut attached to an end of the joint body; a seal member that contacts an outer peripheral surface of a pipe disposed inside the joint body; A resin core that supports the pipe from the inside, The incore is A cylindrical portion disposed inside the pipe; a flange portion provided on an outer peripheral surface of an end portion of the cylindrical portion and in contact with an end surface of the pipe in an axial direction; having A groove for accommodating the flange portion is formed on the inner peripheral surface of the joint body. Pipe fittings.

2. The inner circumferential surface of the joint body is A first inner circumferential surface having a diameter smaller than an outer diameter of the flange portion; a second inner circumferential surface located axially outward of the first inner circumferential surface and having a larger diameter than the first inner circumferential surface; a third inner circumferential surface that forms a step connecting the first inner circumferential surface and the second inner circumferential surface, faces outward in the axial direction, and in which the seal member is disposed; Equipped with The pipe fitting according to claim 1 , wherein the groove is formed in the first inner circumferential surface.

3. 3. The pipe fitting according to claim 2, wherein a portion of the first inner circumferential surface located between the third inner circumferential surface and the groove in the axial direction has a diameter that decreases from the third inner circumferential surface toward the groove.

4. 4. The pipe joint according to claim 2, wherein a portion of the first inner circumferential surface that is located between the third inner circumferential surface and the groove in the axial direction has a length of 6.0 mm or less.

5. 2. The pipe joint according to claim 1, wherein each of the joint body, the nut, and the in-core is made of resin.

6. The pipe joint according to claim 1 , wherein each of the joint body and the nut is made of metal.

7. 2. A method for connecting pipes using the pipe fitting of claim 1, comprising the steps of: With the flange portion housed in the groove and the in-core disposed within the joint body, the pipe is inserted between an inner peripheral surface of the joint body and an outer peripheral surface of the tubular portion. How to connect pipes.

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