JPH0673594U - Branch pipe connection fitting - Google Patents

Abstract

(57) [Summary] [Purpose] When installing a branch pipe connection joint on the main pipe,
When fluid leakage prevention measures are taken in which the sealing member is sandwiched and compressed in the through hole of the main pipe wall so that it bulges in the radial direction and adheres closely to the wall surface of the through hole, the sealing member moves axially in a closed space. Being compressed prevents stress relaxation due to cold flow of the seal member. [Structure] Screw hole 63 of pedestal 6 attached to saddle 4A
The cylindrical support body 7 is screwed into the casing 7, and the flange portion 73 of the cylindrical support body 7 and the protruding portion 64 of the pedestal 6 compress the seal member 8 in the axial direction and swell in the radial direction. The ring body 9 is fixed to the peripheral edge of the opening of the through hole 12, and the through hole 12 is extended in the axial direction.
The seal member 8 bulges radially in a closed space surrounded by the wall surface of the through hole, the collar portion 73 and the projecting portion 64 and closely contacts the wall surface of the through hole.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a branch pipe connecting joint for connecting a branch pipe to a main pipe such as a gas pipe.

[0002]

[Prior art]

 Conventionally, as shown in FIG. 8, when a branch pipe (not shown) is connected to the main pipe 1, a male screw 3a provided in the branch pipe connection joint 3 is screwed into a screw hole 2 formed in the main pipe 1. The joint 3 was connected to the main pipe 1 in a branched manner, and the branch pipe was connected to the branch pipe connection port 3b of the joint 3.

[0003]

[Problems to be solved by the device]

 In the conventional branch pipe connection joint, the smaller the diameter of the main pipe 1, the smaller the curvature of the main pipe 1 and the smaller the number of effective threads of the screw holes 2 on the main pipe 1 side. It becomes difficult to secure a sufficient screwing amount between the screw hole 2 and the male screw 3a on the joint 3 side, and there is a possibility that fluid such as gas flowing in the main pipe 1 may leak to the outside from a portion where the screwing amount is small. There was also a tendency that the joint 3 could not be reliably attached to the main pipe 1 reliably.

On the other hand, recently, a technique has been developed to extend the life of the aged pipe by additionally forming a lining layer on the inner surface of the aged pipe with a hard vinyl chloride resin or the like. However, such a lining layer is formed. When connecting a branch pipe to the pipe, a through hole (corresponding to the screw hole 2 in FIG. 8) is formed in the pipe so that the pipe wall and the lining layer are formed at the place where the through hole is formed. A gap is often created in the pipe, and when a branch pipe is connected using a joint and a fluid flows through the pipe, the fluid may enter the gap between the pipe wall and the lining layer. Then, when the fluid entered the gap between the pipe wall and the lining layer in this way, if the lining layer was not entirely adhered to the inner surface of the pipe wall, fluid that entered the gap occurred in the pipe. There is a risk that the situation of leakage from a corroded place or a place where cracks or cracks have occurred may diminish the significance of forming the lining layer.

Therefore, the applicant of the present application fitted a cylindrical seal member (rubber cylinder) to the shaft portion of the joint inserted into the through hole of the pipe in a fitting manner, and provided the seal member with an annular flat surface. The outer surface of the seal member is brought into close contact with the wall surface of the through hole formed in the pipe by sandwiching it from both sides in the axial direction and compressing it to bulge inward and outward. We previously proposed a method of closing the gap between the pipe wall and the lining layer in the open area with a seal member.

However, in the through hole formed in the pipe, the opening peripheral edge on the inner surface side of the pipe has a three-dimensional closed curved line (two positions located in the axial direction of the opening peripheral edge and two positions located in the peripheral direction of the pipe). It is formed by a three-dimensional closed curve with different levels. Therefore, the tubular seal member is expanded by axially compressing the tubular seal member with the member having the annular plane as described above. If the gap between the wall and the lining layer is closed, the end of the seal member on the inner surface of the pipe is partially exposed to the inner passage side of the pipe at two locations in the pipe axial direction. When the end of the seal member is partially exposed to the inner passage side of the pipe, the rubber layer of the seal member causes a so-called cold flow phenomenon over time. May induce stress relaxation of the seal member, impairing the adhesion performance of the seal member to the wall surface of the through hole, and impairing the reliability of the seal member closing the gap between the pipe wall and the lining layer. Was found.

The present invention has been made under the above circumstances, and the above-described tubular seal member is expanded in the radial direction by compressing the member having an annular flat surface from both sides in the axial direction. Although the above method is basically adopted in which the outer peripheral surface of the sealing member is brought into close contact with the hole wall surface of the through hole formed in the pipe, the seal member does not move in the closed space. By taking measures to compress in the same direction, the stress relaxation of the seal member due to the above cold flow is prevented, and the adhesion performance of the seal member to the hole wall surface of the through hole formed in the pipe is impaired for a long time. It is an object of the present invention to provide a branch pipe connection joint that becomes difficult.

[0008]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the present invention provides a branching aid such as a saddle having a screw hole penetrating through and fixed to a main pipe, and a mounting portion provided with a male screw that can be screwed into the screw hole of the branching aid. Is a cylindrical branch having a central portion in the axial direction, a projecting portion with a screw hole formed on one end side in the axial direction of the mounting portion, and a branch pipe connection port portion formed on the other axial end of the mounting portion. It has a pedestal for pipe connection, a shaft portion having a male screw at one end and capable of being loosely fitted in a through hole for branching formed in the main pipe, and a flange portion provided at the other end of the shaft portion. It is possible to fit the cylindrical support attached to this base by screwing the male screw into the female screw of the above-mentioned screw hole provided on the protruding part of the above-mentioned pedestal, and the shaft part of the cylindrical support in a fitting manner. The annular planes provided on the flange of the cylindrical support attached to the pedestal and the protrusion of the pedestal, respectively. By being sandwiched and compressed in the axial direction, the inner diameter becomes smaller than the outer diameter of the shaft part of the tubular support, and the outer diameter becomes larger than the diameter of the through hole of the main pipe. A cylindrical seal member that can bulge in the direction, and one side opening edge of the inner peripheral surface that is fixed to the opening peripheral edge portion of the through hole on the inner surface of the main pipe and the inner peripheral surface side opening edge of the main pipe in the through hole of the main tube. And a ring body whose other side opening edge is formed by a two-dimensional closed curve.

[0009]

[Action]

 According to the present invention, even if the opening peripheral edge of the through hole formed in the tube on the inner surface side of the tube is formed by a three-dimensional closed curve, one side opening edge of the ring body is aligned with the opening peripheral edge of the through hole. By fixing the ring body to the opening peripheral edge portion of the through hole on the inner surface side of the main pipe, the hole wall surface of the through hole is extended in the axial direction of the through hole by the inner peripheral surface of the ring body. Since the opening edge on the other side of the ring body is formed by a two-dimensional closed curve, the seal member fitted to the shaft portion of the tubular support body is fitted to the flange portion of the tubular support body and the protruding portion of the pedestal. When the seal member is sandwiched between the annular flat surfaces and is axially compressed, the seal member is enclosed in the closed space surrounded by the wall surface of the through hole of the pipe and the annular flat surfaces of the collar portion and the protruding portion. Bulge inward and outward, and the outer peripheral surface of the seal member is brought into close contact with the hole wall surface of the through hole.

By the way, when the main pipe is an aged pipe having a lining layer of hard vinyl chloride resin or the like on its inner surface, when the branch pipe connection joint is attached to the main pipe, the lining layer has a through hole for the main pipe. It is necessary to make a hole corresponding to. In this case, by forming a hole in the lining layer, a gap may be created between the pipe wall of the main pipe and the lining layer at the location where the hole is formed. Is swelled in the closed space in the radial direction, straddles the wall surface of the through hole on the main pipe side and the hole wall surface of the lining layer, and is closed by closely adhering to both wall surfaces.

[0011]

【Example】

 FIG. 1 is a vertical sectional view showing a state in which a branch pipe connecting joint A according to an embodiment of the present invention is attached to a main pipe 1, and FIG. 2 is a sectional view taken along line II-II in FIG.

The main pipe 1 is, for example, a cast iron buried gas pipe, and a lining layer 11 of a predetermined thickness made of hard vinyl chloride resin is additionally provided on the inner surface of the main pipe 1 in order to prolong the life of the aged main pipe 1. Has been done. In addition, a through hole 12 for branching is formed at a predetermined position on the pipe wall of the main pipe 1, and a hole 12 a having substantially the same diameter as the through hole 12 is also formed concentrically in the lining layer 11. There is. Since the lining layer 11 is additionally provided on the inner surface of the main pipe 1, the opening peripheral edge of the lining layer 11 corresponding to the main peripheral surface inner side opening peripheral edge 12b (see FIG. 4) has a three-dimensional closed curve. . That is, the opening peripheral edge 12b on the inner surface side of the main pipe is located at two positions located in the pipe axis direction (indicated by arrow X in FIGS. 2 and 4) and in the pipe circumferential direction (indicated by arrow Y in FIGS. 1 and 3). The three-dimensional closed curve whose level is different from that of the two points located at

The branch pipe connection joint A includes a pair of saddles 4A and 4B arranged on both sides of the main pipe 1, and a fastening member 5 for fastening the pair of saddles 4A and 4B to the main pipe 1. 5, a tubular branch pipe connecting pedestal 6 attached to one saddle 4A, a tubular support 7 attached to the pedestal 6, a tubular sealing member 8, a ring body 9 and the like.

Of the pair of saddles 4A and 4B, one saddle 4A includes an arcuate saddle body 41A that is saddle-ridden on the main pipe 1 and flange portions 42A and 42A that project from both ends of the saddle body 41A. It is integrally provided, and the flange portions 42A, 42A are provided with bolt insertion holes 43A, 43A. A boss 44A is projected at the center of the saddle body 41A, and a screw hole 46A having a female screw 45A is formed by the boss 44A. Further, in this saddle 4A, a recess 47A is provided on the inner surface side of the saddle body 41A so as to surround the above-mentioned screw hole 46A, and a packing 48 is fitted into this recess 47A.

The other saddle 4B integrally includes an arc-shaped saddle body 41B that is saddle-mounted on the main pipe 1 and flange portions 42B and 42B that project from both ends of the saddle body 41B. , 42B are provided with bolt insertion holes 43B, 43B.

The tightening member 5 includes a tightening bolt 51 and a nut 52, and the tightening bolt 51 is inserted into the bolt insertion holes 42A and 42B on the pair of saddles 4A and 4B provided on both sides of the main pipe 1. The nut 52 is fastened to the.

The branch pipe connecting pedestal 6 is formed in a tubular shape, and an attachment portion 62 having a male screw 61 formed to have a small diameter is provided at a central portion in the axial direction of the pedestal 6 for connecting the branch pipe. A protrusion 64 having a screw hole 63 is formed, and a branch pipe connection port 65 is formed on the other end side in the axial direction of the mounting portion 62. The end surface of the protruding portion 64 forms an annular flat surface 64a (see FIG. 4). The pedestal 6 is attached to the saddle 4A by screwing the male screw 61 of the attachment portion 62 into the screw hole 46A of the saddle 4A. A packing 49 is sandwiched between the mounting portion 62 and the main pipe 1 via a retainer 49a.

The tubular support 7 has a shaft portion 72 having a male screw 71 at one end and a flange portion 73 provided at the other end of the shaft portion 72. The shaft portion 72 is provided on the main pipe 1 side. The male screw 71 is attached to the pedestal 6 by being screwed into the female screw 63a of the screw hole 63 of the protruding portion 64 while being fitted in the through hole 12. The upper surface of the collar portion 73 forms an annular flat surface 73a (see FIG. 4).

5 to 7, a half member 9A for forming the ring body 9 is shown by a solid line, and the ring body 9 has two half members 9A shown by a solid line and an imaginary line. It is composed by butting in a ring shape. In the ring body 9 configured by abutting the two half-divided members 9A, 9A, the one opening edge 92 of the inner peripheral surface 91 is fitted to the main tube inner surface side opening peripheral edge 12b of the through hole 12 of the main tube 1. The other side opening edge 93 is formed by a two-dimensional closed curve, while it is formed by a three-dimensional closed curve. The ring body 9 is bonded to the opening peripheral edge portion of the through hole 12 on the inner surface of the main pipe 1 with the one-side opening edge 92 aligned with the main pipe inner surface-side opening peripheral edge 12b as shown in FIGS. It is bonded and fixed using an agent. Therefore, the hole wall surface of the through hole 12 is extended in the axial direction of the through hole 12 by the inner peripheral surface 91 of the ring body 9, and the opening peripheral edge of the extended end portion is formed on the other side opening formed by the two-dimensional closed curve. It becomes the edge 93. It should be noted that the ring body 9 may be a molded body made of a synthetic resin of the same kind or different kinds as the lining layer 11 or a metallic body.

The tubular seal member 8 is fitted to the tubular support 7 attached to the pedestal 6 together with the retainer 81, and the flange portion 73 of the tubular support 7 and the pedestal 7 are attached. It is sandwiched by the projecting portion 64 of the seat 6 and compressed in the axial direction so as to bulge inward and outward in the radial direction. Therefore, as shown in an enlarged view in FIG. 4, the seal member 8 is in close contact with the projecting portion 64 of the pedestal 6, and the wall surface of the through hole 12 on the main pipe 1 side and the hole 13 of the lining layer 11 are formed. It straddles the wall surface and is in close contact with both of these wall surfaces, and further in close contact with the outer surface of the shaft portion 72 of the tubular support 7 on which the male screw 71 is not formed. As for the sealing state of the seal member 8 with respect to each of such parts, as the seal member, the inner diameter becomes smaller than the outer diameter of the shaft portion 72 of the tubular support 7 when compressed in the axial direction, and the outer diameter is It can be obtained by using a pipe 1 that can bulge in the radial direction so as to have a diameter larger than the diameter of the through hole 12.

By the way, a rectangular hole 75 such as a hexagonal hole is formed in the upper part of the inner surface of the cylindrical support 7 used in this embodiment, and as shown in FIG. The cylindrical support 7 can be rotated by the tool 100 by engaging the head portion 101. Therefore, as described above, the ring body 9 is adhered and fixed to the opening peripheral portion of the through hole 12 on the inner surface of the main pipe 1, the saddles 4A and 4B are attached to the main pipe 1, and the pedestal 6 is attached to one saddle 4A. As shown in phantom lines in FIG. 3, the male screw 71 of the cylindrical support body 7 is loosely screwed into the screw hole 63 of the protruding portion 64 of the pedestal 6 as shown in FIG. When the tubular support body 7 is pulled up by engaging the head portion 91 of the shaft 9 with the square hole 75 of the tubular support body 7 and rotating it, the sealing member previously attached to the tubular support body 7 together with the retainer 81. 8 is pushed up by the collar portion 73 and enters the through hole 12 of the main pipe 1 including the hole 12a of the lining layer 11. Therefore, when the cylindrical support 7 is rotated by the tool 9 and the male screw portion 71 thereof is screwed into the screw hole 63 on the pedestal 6 side, the seal member 8 is inserted through the retainer 81 to form a cylindrical shape as described above. The flange portion 73 of the support 7 and the protruding portion 64 of the pedestal 6 are sandwiched by the respective annular flat surfaces 73a and 64a and are compressed in the axial direction to bulge inward and outward in the radial direction to provide a sealing action. It will come to exert. Here, since the other side opening edge 93 of the ring body 9 is formed by a two-dimensional closed curve, the seal member 8 has the hole wall surface of the through hole 12 and the annular planes of the collar portion 73 and the protruding portion 64, respectively. In the closed space surrounded by 73a and 64a, it swells radially inward and radially outward. Therefore, when the cylindrical support 7 is pulled up so that the annular flat surface 73a of the collar portion 73 is positioned higher than the other opening edge 93 of the ring body 9, the outer peripheral surface of the sealing agent 8 is on the main pipe 1 side. Straddling the wall surface of the through hole 12 and the wall surface of the hole of the lining layer 11 and closely adhering to both wall surfaces thereof, the gap between the pipe wall and the lining layer 11 is surely closed, and the seal member 8 is aged. This prevents the situation where the cold flow phenomenon accompanied by stress relaxation occurs and the adhesion performance is impaired.

It is desired that the wall surface of the through hole 12 on the main pipe 1 side and the wall surface of the hole 12a on the lining layer 11 side be polished with a rotary grindstone or the like. The sealing action of the ruler member 8 is surely exhibited. Further, in the lining layer 11, if a liquid sealant or butyl rubber (rubber that plastically flows) is applied or attached in advance to the place where the hole 13 is formed, the airtightness can be further improved.

In this embodiment, the saddles 4A and 4B are used as the branching aids fixed to the main pipe 1, but the saddles 4A and 4B may be replaced so that the pipes can withstand breakage. It is also possible to use a clamp having a long length in the longitudinal direction. Further, the ring body 9 is constructed by abutting two half members 9A, 9A, but this is for the convenience of inserting the ring body 9 into the main pipe 1 using the through hole 12. The ring body 9 may be configured as a circular integral body as long as it can be inserted into the main pipe 1 by utilizing the through hole 12, and the circular integral body can be folded in two. You can also use it.

[0024]

[Effect of device]

 According to the branch pipe connection joint of the present invention, the seal member bulges in the radial direction in the closed space, so that the seal member does not cause a cold flow phenomenon accompanied by stress relaxation over time, and flows in the main pipe. This has the effect of reliably preventing the fluid such as gas from leaking to the outside. In addition to this, even when a lining layer is provided on the inner surface of the main pipe, the sealing member closes the gap between the inner surface of the main pipe and the lining layer, so that the fluid flowing through the main pipe into the gap is The effect is that it can be surely prevented from entering.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a state in which a branch pipe connection joint according to an embodiment of the present invention is connected to a main pipe.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a vertical sectional view exemplifying a procedure of attaching the tubular support body to the branch pipe connection pedestal using a tool.

FIG. 4 is an enlarged cross-sectional view of a main part in FIG.

FIG. 5 is a plan view showing a ring body and a half member that is a component thereof.

6 is a sectional view taken along line VI-VI in FIG.

7 is a cross-sectional view taken along the line VII-VII of FIG.

FIG. 8 is a partially cutaway side view of a conventional example.

[Explanation of symbols]

 A Branch pipe connection joint 1 Main pipe 4A, 4B Saddle (branch auxiliary tool) 5 Tightening member 6 Branch pipe connection pedestal 7 Cylindrical support 8 Seal member 9 Ring body 12 Main pipe through hole 12b Main surface inner side opening edge 46A Screw hole 61 Male screw 62 Mounting part 63 Screw hole 64 Protruding part 64a Annular plane (annular plane) of projecting part 65 Branch pipe connection port 71 Male screw 72 Shaft part 73 Collar part 73a Circular plane of collar part (flange part) 91 Inner peripheral surface of ring body 92 Opening edge on one side of ring body 93 Opening edge on other side of ring body

Front page continued (72) Inventor Tomoyuki Nakao 4-1-2, Hirano-cho, Chuo-ku, Osaka City, Osaka Prefecture Osaka Gas Co., Ltd. Inside this steel pipe fittings (72) Inventor Ryo Otsubo One day at 153 Tajime-cho, Kishiwada, Osaka Prefecture Inside this steel pipe fittings

Claims (1)

[Scope of utility model registration request] 1. A branch assisting tool such as a saddle having a screw hole penetrating therethrough and fixed to a main pipe, and a mounting portion provided with a male screw capable of being screwed into the screw hole of the branch assisting tool is provided at a central portion in an axial direction. And a cylindrical branch pipe connecting pedestal in which a projecting portion having a screw hole is formed on one end side in the axial direction of the mounting portion, and a branch pipe connecting port is formed on the other end side in the axial direction of the mounting portion. A male thread on the pedestal of the above-mentioned pedestal, and a male thread on the pedestal. A tubular support attached to this pedestal by being screwed into a female screw of the provided screw hole, and a tubular support attachable to the pedestal that can be fitted to the shaft of the tubular support Of the ring and the protruding portion of the pedestal, which are sandwiched by annular flat surfaces and compressed in the axial direction. As a result, the inner diameter becomes smaller than the outer diameter of the shaft portion of the cylindrical support, and the outer diameter becomes larger than the diameter of the through hole of the main pipe. The sealing member is fixed to the opening peripheral edge of the through hole on the inner surface of the main pipe, and the one side opening edge of the inner peripheral surface is formed by a three-dimensional closed curve that matches the opening edge on the inner surface side of the main hole of the through hole of the main pipe. A branch body having a side opening edge formed by a two-dimensional closed curve;