JP3051822U - Piping joint structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a main pipe peripheral side surface with a sealing position interposed between a main pipe and a branch pipe and a packing interposed between the main pipe and a branch pipe, while maintaining a reliable connection between the main pipe and the branch pipe, and to a through hole of the main pipe. The present invention provides a pipe joint structure that eliminates the need for special processing, saves processing time, and improves reliability. SOLUTION: By using a packing 4 having a curved surface portion corresponding to a peripheral side surface of a main pipe around a through hole 6f, a close contact between the packing 4 and the main pipe 2 is obtained not on the inside of the through hole 6f but on the outer side of the main pipe. Since the processing of the main pipe 2 can be performed only by the simple through hole 2a, the processing for forming the step is unnecessary, and the processing becomes easy especially when a metal pipe such as a steel pipe is used, and the trouble of the main pipe processing is reduced. The cost can be greatly reduced and the cost can be reduced. In addition, the thickness of the main pipe becomes almost uniform, so that stress concentration hardly occurs and reliability is improved.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a pipe joint structure for integrally connecting a main pipe through which a fluid flows and a branch pipe branched from the main pipe.

[0002]

[Prior art]

 Conventionally, when connecting a main pipe and a branch pipe made of materials having significantly different thermal characteristics such as the coefficient of thermal expansion, such as when a branch pipe of a copper pipe is provided by branching off from the main pipe of a vinyl chloride resin pipe. The connection is designed so that even if the temperature of the fluid flowing inside the piping or the outside temperature greatly changes from room temperature, the difference in characteristics between the main pipe and the branch pipe does not impair the adhesion of the connected parts and cause fluid leakage. For this purpose, a pipe joint structure is used, which secures the adhesion between the main pipe and the branch pipe by means of special auxiliary means.

An example of such a conventional pipe joint structure is disclosed in Japanese Patent Laid-Open No. 7-301384, which is shown in FIG. FIG. 4 is a schematic structural explanatory view of a conventional pipe joint structure.

In FIG. 4, a conventional pipe joint structure 100 includes a main pipe 101 made of a synthetic resin and a metal branch pipe 102 which is integrally connected to the main pipe 101 in a branched state. A through hole 101a having an inner diameter larger than the outer diameter of the pipe 102 and an inner circumference of which is stepped in the axial direction is formed, and a connecting rib portion 102a of the branch pipe 102 is formed. In addition to the main pipe 101 and the branch pipe 102, an O-ring 103 and a holding plate band 104 are provided as auxiliary means for connecting the main pipe 101 and the branch pipe 102, and the connection end portion of the branch pipe 102 is inserted into the through hole 101a of the main pipe 101. Then, the locking rib portion 102a is brought into contact with the step portion 101b on the inner periphery of the through hole 101a via the O-ring 103, and further, a holding plate vane disposed on the outer peripheral surface of the main pipe 101. In this configuration, the main pipe 101 and the branch pipe 102 are tightened by the arm 104 so that the space between the main pipe 101 and the branch pipe 102 is sealed.

[0005] The holding plate band 104 is composed of two substantially semi-circular band members 104a made of metal, and one of the band members 104a is provided with an insertion hole 104b through which the branch pipe 102 passes. I have. Further, both ends of each band body 104a are formed in a flange shape, and holes for passing the connecting bolts 104c are formed. A press flange 104d is provided around the insertion hole 104b so as to press the locking rib portion 102a of the branch pipe 102 toward the inside of the ring.

When the holding plate band 104 is tightened, the holding flange 104 d of the holding plate band 104 pushes the locking rib portion 102 a of the branch pipe 102, and the locking rib portion 102 a is inserted into the insertion hole 101 a of the main pipe 101. The main pipe 101 and the branch pipe 102 communicate with each other without being tightly pressed to the stepped portion 101b provided on the side face via the O-ring 103.

As described above, in the conventional pipe joint structure, even if the pipes are made of dissimilar materials having significantly different thermal characteristics, the connection portion always receives the pressing force from the holding plate band 104 and the O-ring 103 Because of the close contact, the adhesive can maintain the contraction and expansion irrespective of the change of the thermal environment, and the internal fluid does not leak. Further, even if the main pipe 101 and the branch pipe 102 are each formed of different materials having different mechanical strengths, the material having low strength is not destroyed by the generated thermal stress or the like. Furthermore, even if the main pipe 101 and the branch pipe 102 are made of different metal materials, the O-ring 103, which is an insulating material, is inserted between the main pipe 101 and the branch pipe 102 so that the connection can be made in a completely insulated state. Electrolytic corrosion due to formation of a local battery can be prevented.

[0008]

[Problems to be solved by the invention]

 Since the conventional pipe joint structure is configured as described above, in order for the branch pipe 102 to be connected to the main pipe 101 via the O-ring 103 without any gap, the stepped portion 101b in the through hole 101a of the main pipe 101 is required. The branch pipe 102 must be formed by spot facing on a plane parallel to the locking rib 102a. However, such processing is troublesome for metal pipes and the like, and has a problem that the work is troublesome. In addition, since the thickness of the main pipe 101 becomes uneven due to the processing, stress concentration is likely to occur due to deformation due to heat, and in the case of a metal material, durability may decrease due to metal fatigue. did.

The present invention has been made in order to solve the above-mentioned problems, and a reliable connection between the main pipe and the branch pipe is provided by using a position where the packing interposed between the main pipe and the branch pipe is in close contact with the main pipe as a peripheral side face of the main pipe. It is an object of the present invention to provide a piping joint structure that does not require special processing of the through hole of the main pipe, saves labor and reduces cost, and improves reliability.

[0010]

[Means for Solving the Problems]

 The pipe joint structure according to the present invention is a pipe joint structure in which a branch pipe is connected to a through hole formed in a main pipe to integrally connect in a branched state while preventing leakage of internal fluid, and from a connection end of the branch pipe. A locking rib portion projecting over the entire circumference at a side position separated by a predetermined dimension, and a predetermined length having an outer diameter substantially matching the through hole diameter of the main pipe and an inner diameter substantially matching the outer diameter of the branch pipe. Formed by projecting a collar portion at an outer peripheral portion of a substantially tubular body separated by a predetermined distance from one end of the substantially tubular body, and forming a flat surface on one end side of the substantially tubular body of the collar portion. The other end of the substantially tubular body is formed into a curved shape along the peripheral side surface of the main pipe, and the other end side of the substantially tubular body is inserted into a through hole of the main pipe so that the collar portion is connected to the peripheral side of the main pipe. The connection end of the branch pipe is inserted inside the substantially tubular body. A packing made of an elastic material, and an outer diameter portion larger than the through-hole diameter of the main pipe and an outer diameter portion smaller than the portion are formed of a substantially annular body having a step in the axial direction, and an outer diameter of the substantially annular body. The inner diameter in a predetermined dimension range that is larger than the rib width of the locking rib portion from the large diameter side end portion and smaller than the sum of the rib width and the length from one end portion to the collar portion of the packing is locked. The outer diameter of the ribs is larger than the outer diameter of the ribs and smaller than the outer diameter of the ribs of the packing, and the inner diameter outside the predetermined dimension range is larger than the outer diameter of the branch pipe and smaller than the outer diameter of the locking ribs. A backup ring mounted around the branch pipe on the distal end side of the stop rib with its outer diameter large-diameter end facing the locking rib, and a plurality of members connected in a substantially circumferential shape. At least a circle that is larger than the main pipe cross section At least one of the connecting portions between the members is formed so as to be freely connected / separable and the connecting position between the members can be adjusted. An insertion hole having a diameter that allows insertion of the outer pipe and a diameter end that cannot insert the large-diameter side end is formed in a direction facing the center of the substantially annular body. A branch pipe fixing member disposed around the main pipe so as to penetrate a more distal end portion and an outer diameter side end portion of the backup ring, respectively, wherein members at predetermined coupling portions of the branch pipe fixing device are connected to each other. The main pipe and the branch pipe are tightened by changing the circumferential length by adjusting the connection position, and the locking rib portion is inserted through the main pipe with the backup ring partially fitted into the insertion hole of the branch pipe fixing tool. While pressing against the packing attached to the hole, One end of the backup ring is pressed against and tightly attached to the collar of the packing, and between the flange of the packing and the peripheral surface of the main pipe, between one end of the backup ring and the collar of the packing, and the locking rib and the packing. In this case, a sealed state is ensured between one end and the other end. As described above, according to the present invention, it is possible to obtain the close contact between the packing and the main pipe not on the inside of the through hole but on the outer side of the main pipe, using the packing having the curved surface portion corresponding to the circumferential side of the main pipe around the through hole. Therefore, the processing of the main pipe can be performed only with simple through holes, and the processing for forming the step is not required. The cost can be greatly reduced and cost can be reduced, and the thickness of the main pipe becomes almost uniform, so that stress concentration hardly occurs and reliability is improved. In addition, the packing completely insulates between the main pipe and the branch pipe, so that even if the main pipe and the branch pipe are made of different types of metal, no electrolytic corrosion occurs due to direct contact.

In the pipe joint structure according to the present invention, if necessary, the branch pipe fixing member may connect two substantially semi-annular bodies each having the insertion hole formed in one of them at the ends. The two substantially semi-annular bodies are formed into an integral substantially annular body, and one end of each of the two substantially semi-annular bodies that are connected to each other is formed in a substantially flange shape facing each other, and a bolt hole is formed therein. The distance between the ends is connected to the bolt hole through a connecting bolt so that the distance between the ends can be adjusted, and the other end of the two substantially semi-annular bodies is directly connected to be detachable. As described above, according to the present invention, the branch pipe fixing device is a substantially annular body composed of two substantially semi-annular bodies, and the connection and the tightening of the main pipe and the branch pipe can be performed by tightening bolts, thereby assembling and tightening. The work becomes easier, the work can be made more efficient, and the structure is simplified and the cost can be reduced.

In the pipe joint structure according to the present invention, if necessary, the branch pipe fixing member is formed by bending a metal plate into a substantially semi-annular shape, and an insulating surface is provided on the surface in contact with the main pipe. It is coated with a conductive material. As described above, according to the present invention, since the branch pipe fixing device is made of a metal having an appropriate spring property, even if the packing changes over time, the main pipe and the branch pipe are kept in close contact with an appropriate pressure and leaks. The prevention effect can be maintained, and furthermore, the inner coating can keep the insulation between the main pipe and the branch pipe, and can also prevent electrolytic corrosion caused via the branch pipe fixing tool.

[0013]

[Embodiment of the invention]

 Hereinafter, a pipe joint structure according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic plan view of a pipe joint structure according to the present embodiment, FIG. 2 is an exploded perspective view of a main part of the pipe joint structure according to the present embodiment, and FIG. 3 is a pipe joint according to the present embodiment. FIG. 3 is an explanatory view of a compressed state of the packing in the structure.

In each of the drawings, a pipe joint structure 1 according to the present embodiment has a main pipe 2 and a branch pipe 3 that are integrally connected in a branched state. In addition to the main pipe 2 and the branch pipe 3, the main pipe 2 and the main pipe 2 are formed with a through hole 2a having a large inner diameter and a locking rib 3a formed all around a predetermined position near the end of the branch pipe 3. As a connecting means for connecting the branch pipes 3, it is formed of a substantially tubular body having a predetermined length with a flange 4 a protruding from an outer peripheral portion, is inserted into the through hole 2 a of the main pipe 2, is disposed, and is disposed inside. The packing 4 made of an elastic material into which the connecting end of the branch pipe 3 is inserted, and the outer circumference and the inner circumference are formed of a substantially annular body having a step in the axial direction, and are located on the distal side from the locking rib 3a. A backup ring 5 attached around the branch pipe 3 and a metal plate bent substantially semi-circularly One of the band members 6a and 6b is connected at one end thereof via a connection bolt 6c, and the other end is connected directly and detachably to each other to form a substantially annular body integrally formed. And a branch pipe fixing tool 6 disposed in the main body.

The packing 4 is formed of a substantially tubular body having a predetermined length whose outer diameter substantially matches the diameter of the through hole 2 a of the main pipe 2 and whose inner diameter substantially matches the outer diameter of the branch pipe 3. A flange 4a is formed by projecting a flange 4a from an end of the tubular body at a predetermined dimension away from the one end of the tubular body. Is formed in a curved shape along the peripheral side surface of the main pipe 2. The other end of the substantially tubular body is inserted into the through hole 2 a of the main pipe 2, and the collar 4 a is brought into close contact with the peripheral side surface of the main pipe 2. It will be arranged.

The backup ring 5 is formed of a substantially annular body in which an outer diameter portion larger than the diameter of the through hole 2a of the main pipe 2 and an outer diameter portion smaller than this diameter are stepped in the axial direction. A dimension that is larger than the rib width of the locking rib portion 3a of the branch pipe 3 from the outer diameter large-diameter side end portion of the annular body, and that this rib width is combined with the length from one end of the packing 4 to the collar portion 4a. The inner diameter in the smaller predetermined dimension range is formed to be larger than the outer diameter of the locking rib portion 3a of the branch pipe 3 and smaller than the outer diameter of the flange portion 4a of the packing 4. The locking rib portion 3a is formed to be larger than the outer diameter and smaller than the outer diameter of the locking rib portion 3a. It is configured to be mounted toward the 3a side.

The branch pipe fixing device 6 has a substantially annular shape larger than the cross section of the main pipe 2 in which two band bodies 6 a and 6 b formed by bending a metal plate into a substantially semi-annular shape are connected at their ends to be integrated. It is a configuration formed by the body. One of the two ends of the two band members 6a and 6b forming the branch pipe fixing device 6 is formed in a substantially flange shape facing each other, and has a bolt hole 6d formed therein. In this configuration, the distance between the ends is adjusted so as to be adjustable through a connection bolt 6c. The other end of the two band members 6a and 6b connected to each other is formed with a notch 6e that can be engaged with each other, and is directly connected detachably by the notch 6e. One of the band members 6a of the branch pipe fixing member 6 has a substantially circular insertion hole 6f into which the outer diameter small-diameter end of the backup ring 5 can be inserted and the outer diameter large-diameter end cannot be inserted. Drilled in the direction toward the center of the ring. The inner surfaces of the two band members 6a and 6b that are in contact with the main pipe 2 are each coated with an insulating material such as rubber or resin.

Next, an operation of assembling the pipe joint structure based on the above configuration will be described. First, the other end of the packing 4 is inserted into the through hole 2a of the main pipe 2, and the curved surface side of the flange 4a is brought into close contact with the peripheral side surface of the main pipe 2. In addition, a backup ring 5 is attached to the distal end of the branch pipe 3 from the locking rib 3a with its outer diameter and the large-diameter end facing the locking rib 3a. The band body 6a of the branch pipe fixing device 6 is mounted on the distal end side of the ring 5 with its inner surface facing the locking rib 3a. The backup ring 5 and the band body 6a are moved toward the connection end of the branch pipe 3, the inside of the backup ring 5 is brought into contact with the locking rib 3a of the branch pipe 3, and the backup ring is inserted into the insertion hole 6f of the band body 6a. In this state, the outer diameter small diameter side end of No. 5 is fitted.

Thereafter, the connecting end side of the branch pipe 3 is inserted into the packing 4 attached to the through hole 2 a of the main pipe 2, and the locking rib 3 a is brought into contact with one end of the packing 4. Then, the other band body 6b is combined with the band body 6a of the branch pipe fixing device 6 by engaging the notches 6e with each other, and is arranged around the main pipe 2. Further, the connecting bolt 6c is inserted into each bolt hole 6d. The band body 6a and the band body 6b are connected to each other to form an integral branch pipe fixing tool 6.

When the circumferential length of the branch pipe fixing tool 6 is changed by tightening the connecting bolt 6 c of the branch pipe fixing tool 6, the branch pipe fixing tool 6 partially fits into the insertion hole 6 f. The locking ring 3a of the branch pipe 3 is strongly pressed against the one end of the packing 4 by the backup ring 5 so as to be in close contact with the one end of the packing 4 (see FIG. 3 (A)). The pressing force is applied to the flange 4a of the packing 4 (see FIG. 3 (B)), and the pressing force is transmitted to the flange 4a (see FIG. 3 (C)). Closely adhere to the side. Thus, between the collar 4a of the packing 4 and the peripheral side surface of the main pipe 2, between the collar 4a and the backup ring 5, and between the locking rib 3a of the branch pipe 3 and one end of the packing 4, respectively. When the sealing state is secured, the tightening of the connecting bolt 6c is completed.

Even after tightening, the metal branch pipe fixing tool 6 has an appropriate spring property, and the packing 4 is subject to aging by constantly biasing the backup ring 5 toward the main pipe 2. Even if this occurs, the optimal crimping and sealing state between the main pipe 2 and the branch pipe 3 can be maintained, and the effect of preventing leakage can be maintained for a long time.

As described above, in the pipe joint structure according to the present embodiment, the packing 4 having the curved-shaped flange 4a fitted to the peripheral side surface of the main pipe 2 around the through hole 2a is used, and the flange 4a and the main pipe 2 are used. Since reliable contact with the peripheral side surface can be obtained, the through-hole 2a of the main pipe 2 can be formed in a simple shape without a step, etc., and the processing of the main pipe 2 is facilitated. The cost can be reduced, and the thickness of each part of the main pipe 2 becomes substantially uniform due to the simple shape of the through-hole 2a, so that stress concentration hardly occurs and the reliability of the connection portion can be improved. Further, since the branch pipe fixing device 6 can tighten the main pipe 2 and the branch pipe 3 by bolting, the assembling and tightening work becomes easy, and the work efficiency can be improved.

In the pipe joint structure according to the above-described embodiment, the branch pipe fixing tool 6 is made of a metal plate having an appropriate resilience. In the same manner as described above, even if the packing 4 is aged over time, the main pipe 2 and the branch pipe 3 can be kept in close contact with each other with an appropriate pressure to prevent leakage. In addition to this, it is possible to maintain the insulation between the main pipe 2 and the branch pipe 3 without the need for an inner coating, to prevent electrolytic corrosion, and to save processing time.

[0024]

[Effect of the invention]

 As described above, in the present invention, the packing and the main pipe are adhered not on the inside of the through hole but on the outer side of the main pipe, using the packing having the curved surface portion corresponding to the peripheral side of the main pipe around the through hole. As a result, the processing of the main pipe can be made only with a simple through hole, and the processing for forming the step is unnecessary, and the processing becomes easy especially when a metal pipe such as a steel pipe is used. The labor can be greatly reduced and the cost can be reduced. In addition, since the thickness of the main pipe is almost uniform, stress concentration hardly occurs and the reliability is improved. In addition, the packing completely insulates between the main pipe and the branch pipe, so that even if the main pipe and the branch pipe are made of different types of metal, there is an effect that no electrolytic corrosion occurs due to direct contact. Also, in the present invention, the branch pipe fixing device is a substantially annular body composed of two substantially semi-annular bodies, and the connection and the tightening of the main pipe and the branch pipe can be performed by tightening bolts, so that the assembling and tightening work is easy. This has the effect that the work can be made more efficient, the structure can be simplified and the cost can be reduced. In addition, in the present invention, the branch pipe fixing device is made of metal having an appropriate spring property, so that even if the packing changes over time, the main pipe and the branch pipe are kept in close contact with an appropriate pressure and leaks. The prevention effect can be maintained, and furthermore, the inner coating can maintain the insulation between the main pipe and the branch pipe, and can also prevent the electrolytic corrosion caused by the branch pipe fixing tool.

[Brief description of the drawings]

FIG. 1 is a schematic configuration plan view of a pipe joint structure according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view of a main part of the pipe joint structure according to the embodiment of the present invention.

FIG. 3 is an explanatory view of a compressed state of packing in the pipe joint structure according to the embodiment of the present invention.

FIG. 4 is a schematic structural explanatory view of a conventional pipe joint structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 100 Piping joint structure 2, 101 Main pipe 2a, 101a Through hole 3, 102 Branch pipe 3a, 102a Locking rib part 4 Packing 4a Collar part 5 Backup ring 6 Branch pipe fixing tool 6a, 6b Band body 6c, 104c Connection Bolt 6d Bolt hole 6e Notch 6f, 104b Insertion hole 101b Step 103 O-ring 104 Holding plate band 104a Band body 104d Holding flange

Claims (3)

[Utility model registration claims] 1. A pipe joint structure in which a branch pipe is connected to a through hole formed in a main pipe to integrally connect in a branched state while preventing leakage of internal fluid, wherein a predetermined distance from a connection end of the branch pipe is provided. A locking rib portion protruding over the entire circumference at a side surface position; and a substantially tubular body of a predetermined length having an outer diameter substantially matching the through hole diameter of the main pipe and an inner diameter substantially matching the outer diameter of the branch pipe. The flange is formed by projecting a flange portion at an outer peripheral portion of a substantially tubular body separated by a predetermined distance from one end of the substantially tubular body, and a side surface of the substantially tubular body at one end side of the flange is formed in a flat and substantially tubular shape. The side surface at the other end of the body is formed in a curved shape along the peripheral side surface of the main pipe, and the other end side of the substantially tubular body is inserted into a through hole of the main pipe so that the collar portion is closely attached to the peripheral side surface of the main pipe. A packing made of an elastic material into which the connecting end of the branch pipe is inserted inside the substantially tubular body. An outer diameter portion larger than the through-hole diameter of the main pipe and an outer diameter portion smaller in diameter than the portion are formed of a substantially annular body that is stepped in the axial direction, and the outer diameter large-diameter side end of the substantially annular body is An inner diameter in a predetermined size range larger than the rib width of the locking rib portion and smaller than a sum of the rib width and the length from one end portion to the collar portion of the packing is larger than the outer diameter of the locking rib portion; The packing is formed so as to have a smaller outer diameter than the collar outer diameter, and an inner diameter other than the predetermined dimensional range is formed to be larger than the outer diameter of the branch pipe and smaller than the outer diameter of the locking rib portion. A backup ring mounted around the branch pipe with the outer diameter large-diameter end facing the locking rib side; and a plurality of members connected in a substantially circumferential shape at least substantially larger than the main pipe cross section. Said member formed of an annular body At least one of the connecting portions is formed so as to be freely connectable / disconnectable and the connecting position of the members can be adjusted, and the outer diameter small diameter side end of the backup ring can be inserted into the predetermined member and the outer diameter large diameter side end An insertion hole having a diameter into which a portion cannot be inserted is formed so as to face the center of the substantially annular body, and a portion of the insertion hole on the end side of the locking rib portion of the branch pipe and outside the backup ring. A branch pipe fixing member disposed around the main pipe by penetrating the small-diameter side end portion, and adjusting a connecting position of members at a predetermined connecting portion of the branch pipe fixing member to adjust a circumferential length. The main pipe and the branch pipe are tightened by changing, and the locking rib portion is pressed against the packing attached to the through hole of the main pipe by the backup ring partially fitted in the insertion hole of the branch pipe fixing tool. Along with the backup ring one end side Press against the packing flange to bring it into close contact, between the packing brim and the peripheral side of the main pipe, between the backup ring one end and the packing brim, and between the locking rib and the packing one end. A pipe joint structure characterized by ensuring a sealed state. 2. The pipe joint structure according to claim 1, wherein the branch pipe fixing member connects two substantially semi-annular bodies each having the insertion hole formed in one of them at an end. The two substantially semi-annular bodies are formed in a substantially annular shape, and one of the ends connected to each other of the two substantially semi-annular bodies is formed in a substantially flange shape facing each other, and a bolt hole is drilled,
A pipe joint, wherein the connection between the ends is adjustable through a connecting bolt to the bolt hole and the other of the ends of the two substantially semi-annular bodies is directly connected detachably. Construction. 3. The pipe joint structure according to claim 2, wherein the branch pipe fixing member is formed by bending a metal plate into a substantially semi-annular shape, and has an insulating property on a surface in contact with the main pipe. A pipe joint structure characterized by being coated with a material.