JP2020067137A - Insulation joint structure - Google Patents

Abstract

To provide an insulation joint structure capable of maintaining an insulation function between different types of metal materials even when an unexpected external force occurs due to an earthquake, uneven settlement and the like.SOLUTION: An insertion port pipe part 3 has a flange part 3b formed integrally with an insertion port part 3a and extending in the outer diameter direction. A push ring 5 is interposed between a flange part 2b of a receiving port pipe part 2 and the flange part 3b of the insertion port pipe part 3 in an insulated state, and a back surface 5d of the push ring 5 is supported by the flange part 3b of the insertion port pipe part 3. A fastening member 6 is stretched between the flange part 2b of the receiving port pipe part 2 and the flange part 3b of the insertion port pipe part 3, and is inserted in an insulated state.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an insulating joint structure in which fluid tubes made of different metal materials are connected in an insulated state.

  A fluid pipeline is constructed by sequentially connecting the ends of multiple fluid pipelines in a sealed state.These fluid pipelines have the required structural strength, earthquake resistance, and weather resistance at their respective piping positions. Alternatively, tubes made of various materials are applied depending on the cost and the like. In such a fluid pipe, when the fluid pipes whose end portions are adjacently connected to each other are different metal pipes such as a stainless steel pipe and a ductile cast iron pipe, they are dissimilar to each other via a fluid such as water. Due to the potential difference between the metals, so-called galvanic corrosion occurs in the electrical contact portion connected between the end portions of the metal tube, and the corrosion area increases with age, and leakage may occur from the connection portion between these end portions. was there.

  Conventionally, in order to prevent corrosion caused by such a potential difference between different kinds of metals, the surface of the push ring axially engaged with the outer surface of the insertion tube made of, for example, a metal material is covered with an insulating member. , And a part of the inner surface of the receiving tube made of a dissimilar metal material is covered with an insulating member in the same manner, so that the inserting tube and the receiving tube are fitted to each other via a sealing material. There is a structure in which a push ring and a socket pipe are fastened together while avoiding electrical contact at the connection portion (for example, see Patent Document 1).

JP-A-2015-143524 (page 7, FIG. 2)

  However, in Patent Document 1, when an external force such as an earthquake or unequal subsidence occurs, these pipes are connected to each other while the insertion pipe and the reception pipe are connected as described above. As a result of inclining and sliding with respect to the shaft, the insertion tube and the push ring or locking member that engages with this and the receiving tube are exposed metal parts that do not require insulation in the normal connection state. There is a problem in that the metal material is exposed by the contact or by the above-described behavior causing peeling or biting in the coating layer of the insulating member, and the dissimilar metals contact each other at the exposed portion. In particular, in the case of a large-diameter pipe, the displacement amount of the pipe is large even at a slight inclination angle, and the bending moment acting on the pipe line is large, so that there is a tendency that different metals come into contact with each other.

  The present invention has been made in view of such a problem, and provides an insulating joint structure capable of maintaining an insulating function between different kinds of metal materials even if an unexpected external force such as an earthquake or an uneven settlement occurs. The purpose is to do.

In order to solve the above problems, the insulating joint structure of the present invention,
A receiving pipe portion made of a metal material and having a flange portion extending in the outer diameter direction at the opening end, and the receiving pipe portion made of a different metal material and inserted into the receiving pipe portion. An insertion tube part having an insertion part, a seal member for sealing between the receiving tube part and the insertion tube part, a push ring for pressing the sealing member, the receiving tube part and the insertion tube An insulating joint structure comprising at least a fastening member for fastening a portion,
The mouthpiece tube portion has a flange portion that is formed integrally with the mouthpiece portion and extends in the outer diameter direction, and the pusher ring includes the flange portion of the mouthpiece pipe portion and the mouthpiece pipe portion. While being insulated from the flange portion, the back surface of the push wheel is supported by the flange portion of the insertion pipe portion, and the fastening member is the collar portion of the receiving pipe portion. It is characterized in that it is inserted in an insulated state so as to extend over the flange portion of the insertion tube portion.
According to this feature, since the flange portion that is integrally formed on the insertion portion of the insertion pipe portion that is inserted into the reception pipe portion is fastened to the flange portion of the reception pipe portion by the fastening member, the earthquake Even if an unexpected external force such as unequal subsidence occurs, the insertion pipe part is not bent, and the receiving pipe part and the insertion pipe part are integrated without relative movement. It is possible to stably press the seal member by the push ring supported by the flange portion and maintain the sealed state of both pipe portions while maintaining the high insulation state of the pipe portion.

The fastening member is inserted in the push ring in an insulated state.
According to this feature, it is possible to integrate the receiving pipe portion, the insertion pipe portion, and the push ring interposed therebetween with the fastening member positioned.

The back surface of the push wheel is in surface contact with the flange portion of the insertion tube portion.
According to this feature, the direction of the push wheel that presses the seal member can be positioned by the flange portion.

The front surface of the push wheel is in surface contact with the flange portion of the receiving pipe portion.
According to this feature, the insertion tube portion, the push ring, and the receiving tube portion can be positioned in the direction in which they are connected to each other.

It is characterized in that the push wheel has a pressing portion that projects toward the inside of the receiving pipe portion and presses the seal member.
According to this feature, the sealing property of the sealing member can be enhanced by pressing the seal member arranged between the receiving pipe portion and the insertion pipe portion toward the inside of the receiving pipe portion.

An expansion joint having at least elasticity is configured at the other end of the receiving pipe portion or the insertion pipe portion.
According to this feature, the expansion and contraction function of the fluid conduit is ensured by the expansion joint formed at one of the other ends while exerting the insulating function without moving the receiving pipe part and the insertion pipe part relative to each other. can do.

FIG. 3 is a schematic diagram showing a fluid conduit to which the insulating joint structure according to the first embodiment is applied. It is a side sectional view showing an insulating joint structure. It is a side sectional view showing the state where the push ring and the seal member were externally fitted to the mouthpiece part. It is a sectional side view which shows the state which has fastened the mouthpiece pipe part to the mouthpiece pipe part with a fastening member. It is a side sectional view showing the state where fastening of a mouthpiece tube part and a mouthpiece tube part was completed. (A) is a rear view of an insertion pipe part, (b) is a partial cross section side view similarly. (A) is a rear view of a push wheel, (b) is a XX sectional view of (a), (c) is a YY sectional view of (a). It is a sectional side view which shows the insulation joint structure to which the push ring which concerns on a 1st modification is applied. It is a sectional side view which shows the insulation joint structure to which the push ring which concerns on a 2nd modification is applied. It is a sectional side view which shows the insulation joint structure which applied the insulation coating layer which concerns on a modification.

  Modes for carrying out the insulating joint structure according to the present invention will be described below based on Examples.

  The insulating joint structure according to the first embodiment will be described with reference to FIGS. 1 to 10. First, reference numeral 1 in FIG. 1 is an insulating joint structure according to the present invention. Further, in this embodiment, the insertion direction of the insertion tube portion will be described as a front direction (front surface).

  As shown in FIG. 1, the fluid conduit 100 of the present embodiment is configured by sealingly connecting a plurality of fluid pipes in order to circulate tap water as its internal fluid. Along the ground, it is buried in the ground, and fluid pipes are sequentially arranged beyond the ground and rivers. The fluid pipeline 100 includes, for example, a stainless steel or steel pipe bridge portion 100a installed over a river and an embedded portion 100c made of, for example, ductile cast iron that is embedded in the ground and extends or contracts or is a flexible pipe. 101 and a connecting portion 100b made of stainless steel or steel, and such an expandable / contractible tube 101 causes an unexpected external force such as a temperature change or an earthquake on the pipe bridge portion 100a and the connecting portion 100b. It absorbs external force that causes relative movement such as expansion and contraction, bending and twisting.

  Although the fluid conduit 100 is a relatively large diameter pipe in the present embodiment, it is not limited to this and may be a small diameter pipe. Further, although the fluid in the fluid pipeline 100 is tap water, the fluid flowing inside the fluid pipe is not necessarily limited to tap water, and may be, for example, agricultural water, industrial water, sewage, etc., or gas or a mixture of gas and liquid. It may be a liquid mixture. Furthermore, the fluid pipeline to which the insulating joint structure according to the present invention is applied is not necessarily limited to the one including the pipe bridge portion, the connecting portion, and the buried portion.

  The insulating joint structure 1 according to the present embodiment is electrically insulated from the connecting portion 100b supported by the rigid body 12 such as the concrete abutment that serves as the abutment of the pipe bridge portion when the embedded portion 100c is laid. It is a structure that is interposed in the state. In this embodiment, an aspect used when connecting the socket pipe part 2 connected to the end of the embedded part 100c and the socket pipe part 3 welded to the end of the connection part 100b will be described. . As shown in FIG. 2, this insulating joint structure 1 is mainly composed of an inlet pipe portion 2, an insertion pipe portion 3, a seal member 4, a push ring 5, and a fastening member 6.

  Next, the inlet pipe part 2, the insertion pipe part 3, the seal member 4, the push ring 5, and the fastening member 6 which constitute the insulating joint structure 1 will be described. As shown in FIG. 2, the receiving tube portion 2 is arranged at one end side of the expandable flexible tube 20 in the present embodiment, and includes the fluid pipe portion 2p, the receiving portion 2a, and the receiving portion 2a. It is mainly composed of a flange portion 2b extending in the outer diameter direction at the open end of the.

  More specifically, as shown in FIG. 3, the receiving pipe portion 2 is continuous with the inner peripheral edge of the flange end surface 2c, and is formed with a recess 2d formed inward in the pipe axis direction, and a recess 2d with the rear end surface of the recess 2d. The inner cylindrical portion 2e has a smaller diameter than the inner cylindrical portion 2e and extends inward in the pipe axis direction, and the inner protruding portion 2g is connected to the annular end surface 2f formed at the inner end of the inner cylindrical portion 2e and protrudes in the inner diameter direction. Further, the flange portion 2b is provided with a plurality of bolt holes 2h penetrating in parallel to the pipe axis direction along the circumferential direction, and the bolts 7 constituting the fastening member 6 are inserted into the bolt holes 2h. It is like this.

  The inlet pipe portion 2 of this embodiment is made of ductile cast iron, and the surface thereof is only subjected to ordinary rust prevention treatment by coating or the like, and the surface of the inlet pipe portion 2 is subjected to a special insulation treatment. Has not been applied. However, the present invention is not limited to this, and the surface of the socket 2 may be subjected to insulation treatment.

  Further, as shown in FIG. 2, the other end side of the expansion and contraction flexible tube 20 is formed as a flexible tube side case 31 that constitutes an expansion and contraction flexible tube joint 30 which is an expansion joint of the present embodiment. Explaining the expansion and contraction flexible tube joint 30, the flexible tube side case 31 and the seat 32 formed at the other end of the expansion and contraction flexible tube 20 are the bayonet claws 31 a formed at the end of the flexible tube side case 31. And a bayonet is engaged by a bayonet claw 32a formed on the seat 32. Further, the spherical member 34 having a spherical outer surface is arranged between the flexible tube side case 31 and the insertion tube 41 constituting the embedded portion 100c, and the flexible tube side case 31 is provided by the seal member 35. The spherical member 34 and the spherical member 34 are hermetically sealed, and the sealing member 36 seals the spherical member 34 and the insertion tube 41. In addition, a groove 41a is provided on the outer periphery of the distal end side of the insertion tube 41, and in order to prevent the flexible tube side case 31 and the insertion tube 41 from expanding and contracting while allowing them to be separated from each other. A locking member 42 is provided. Further, a dust cover 33 and dust ring 37 are provided so that foreign matters and the like do not enter the expandable flexible pipe joint 30.

  By providing the expansion / contraction flexible pipe joint 30 as described above, the flexible tube-side case 31 and the insertion tube 41 are sealed inside, while the flexible tube-side case 31 is provided with Since it can be moved in the axial direction and can be rotated by the spherical member 34, it can be expanded and contracted without relatively moving the receiving pipe portion 2 and the inserting pipe portion 3 in the insulating joint structure 1 described later. The expansion / contraction function and the flexible function can be provided in the conduit by the expansion / contraction flexible pipe joint 30 despite the restriction.

  In addition, in the present embodiment, the expansion and contraction flexible pipe joint 30 is provided at the end portion on the opposite side of the receiving pipe portion 2, but not limited to this, for example, at the end portion on the opposite side of the insertion pipe portion 3. A telescopic flexible pipe joint may be provided. Further, the expansion / contraction flexible pipe joint is not necessarily limited to the expansion / contraction flexible pipe joint and may be at least an expansion / contraction pipe joint having an expansion / contraction function.

  Next, the insertion tube part 3 will be described with reference to FIGS. 3 and 6. The insertion pipe part 3 is a straight tubular member, has an opening end at one end in the pipe axis direction, and extends linearly along the pipe axis direction so that it can be inserted into the reception part 2 a of the reception pipe part 2. And the flange portion 3b protruding in the outer diameter direction at the proximal end side of the insertion port portion 3a in the tube axis direction, and the flange portion 3b which is continuous with the insertion port portion 3a and which is opposite in the tube axis direction from the flange portion 3b. It mainly comprises a fluid pipe portion 3p extending to the side.

  Further, the front surface 3c of the flange portion 3b facing the receiving portion 2a side is formed in a flat surface shape extending in a direction substantially orthogonal to the pipe axis, and penetrates the front surface 3c and the rear surface 3d of the flange portion 3b. Plural bolt holes 3h are formed along the circumferential direction. Further, the other end portion 3r (see FIG. 6) connected to the fluid pipe portion 3p in the pipe axis direction is hermetically connected to the end portion of the connection portion 100b by welding in this embodiment.

  In the spout tube portion 3 of the present embodiment, the tubular members forming the spout portion 3a and the fluid pipe portion 3p and the flange portion 3b are integrated by welding, and this welding material allows the rear surface of the flange portion 3b to be formed. A thick wall portion 3g is formed in the radial direction and the pipe axis direction on the inner peripheral base portion of 3d. Further, the radial thickness of the insertion opening 3a is thicker than the thickness of the fluid pipe portion 3p on the side of the other end 3r, thereby increasing the rigidity of the insertion opening 3a.

  The spout tube portion 3 is a different metal from the spout tube portion 2 and is made of a metal such as steel or stainless steel, and the entire surface thereof is subjected to ordinary rust prevention treatment. Further, the insertion tube portion 3 is coated with a nylon coat in the present embodiment on the entire surface of the fluid pipe portion 3p excluding the insertion portion 3a, the flange portion 3b and the inner peripheral portion of the bolt hole 3h, and the other end portion 3r side. Insulation treatment is performed, that is, the insulating coating layer C is formed. The insulating treatment is not limited to nylon coating, and may be a coating of the insulating material made of another material such as rubber lining, plastic coating, epoxy resin powder coating, coating, dipping, or spraying on the surface. Furthermore, the spout tube portion 3 may be formed, for example, at one end or both ends of a straight tubular or curved tubular fluid pipe, or at one end or both ends of a connecting member such as a fluid valve connected to a pipeline. May be done.

  Next, the push wheel 5 will be described with reference to FIGS. The push wheel 5 of the present embodiment is made of ductile cast iron integrally with the socket tube portion 2, or is formed of an annular member that is divided and formed in the circumferential direction and the pipe axis direction. The metal material forming the push ring 5 is preferably the same metal as the socket tube portion 2 of the socket tube portion 2 and the socket tube portion 3 which are different metals as in the present embodiment. Further, the push wheel 5 is connected to the inner peripheral surface of the push wheel 5 and protrudes annularly in one direction of the pipe axis to press the seal member 4 as will be described later. It mainly includes a front surface 5c extending in a flat surface shape in a direction substantially orthogonal to the axis, and a back surface 5d extending in a flat surface shape in a direction substantially orthogonal to the tube axis on the opposite side of the protrusion 5a and the front surface 5c. Further, a taper surface 5b that gradually extends forward toward the outer diameter side is provided at the front end of the protruding portion 5a in the tube axis direction, and further a bolt hole 5h penetrating the front surface 5c and the back surface 5d and penetrating therethrough is provided along the circumferential direction. Have multiple. The inner diameter of the push ring 5 is formed slightly larger than the outer diameter of the insertion port 3a of the insertion tube 3, that is, the push ring 5 can be loosely fitted to the outer periphery of the insertion port 3a.

  Further, in this embodiment, the entire surface of the push ring 5 including the protrusion 5a of the push ring 5, the front face 5c, the back face 5d and the inner periphery of the bolt hole 5h is subjected to an insulation treatment by applying a nylon coat, that is, an insulating coating layer. D is formed. The insulating treatment is not limited to nylon coating, and may be a coating of the insulating material made of another material such as rubber lining, plastic coating, epoxy resin powder coating, coating, dipping, or spraying on the surface. As described above, the push wheel 5 is subjected to an insulation treatment that is insulated from both the socket pipe portion 2 and the insertion pipe portion 3 that sandwich the push wheel 5 as described later.

  Next, the seal member 4 will be described. As shown in FIG. 3, the seal member 4 is formed of a resin material such as rubber having elasticity, and has an annular shape having an inner diameter slightly smaller than the outer diameter of the insertion opening 3 a of the insertion insertion tube 3. is doing. The seal member 4 has a valve portion 4a having a substantially circular cross-section in a natural state at a front end thereof, and a pressed surface 4b at a rear end thereof which faces the tapered surface 5b of the protruding portion 5a of the push wheel 5 substantially in parallel. The projecting portion 5a of the push wheel, the outer peripheral surface of the insertion opening portion 3a, the inner tubular portion 2e of the receiving opening portion 2a, and the annular end surface 2f are housed in a compressed state in a space surrounded by the receiving pipe portion 2 and the insertion pipe portion. Seal between 3 and 3.

  The procedure for assembling the insulating joint structure 1 including the inlet pipe portion 2, the insertion pipe portion 3, the seal member 4, and the push ring 5 will be described. As shown in FIG. 3, first, the surfaces of the receiving pipe portion 2, the insertion pipe portion 3, the seal member 4 and the push ring 5 are cleaned, and the push ring 5 and the seal member 4 are inserted into the insertion pipe portion of the insertion pipe portion 3. It is fitted onto 3a. At this time, it is preferable to apply a lubricant to the outer surface of the insertion opening 3a, the inner surface of the inner tubular portion 2e of the receiving opening 2a, and the like, if necessary.

  Subsequently, as shown in FIG. 4, work bolts that form the temporary fastening member 16 in the bolt hole 3h of the insertion pipe part 3, the bolt hole 5h of the push ring 5, and the bolt hole 2h of the receiving pipe part 2. The insertion pipe part 3 is inserted into the receiving pipe part 2 by inserting 17 and fastening the nut 18 screwed to the work bolt 17. It is preferable that the work bolt 17 has a relatively long axial length and is a T-head bolt as in the present embodiment because the fastening work can be easily performed. First, in the initial set state, the pressed surface 4b of the seal member 4 is arranged so as to be pressed by the protruding portion 5a of the push wheel 5 supported by being in surface contact with the front surface 3c of the flange portion 3b of the insertion tube portion 3. Then, when the socket pipe portion 2 and the insertion pipe portion 3 are gradually pulled in the pipe axis direction by tightening the work bolt 17 and the nut 18, as shown in FIG. 5, the seal member 4 is The valve member 4a of the seal member 4 is mainly compressed by being pushed in between the inner cylindrical portion 2e of the receiving pipe portion 2 and the outer peripheral surface of the insertion portion 3a.

  Since the back surface 5d of the push wheel 5 is in surface contact with the flange portion 3b of the insertion tube portion 3 in this manner, the direction of the push wheel 5 that presses the seal member 4 can be positioned by the flange portion 3b. Further, since there is no gap between the back surface 5d of the push wheel 5 and the flange portion 3b of the insertion tube portion 3, and there is no sliding during the tightening by the temporary fastening member 16, there is an influence such as peeling of the insulating coating layer. Can be avoided.

  Further, at this time, the protruding portion 5a of the push wheel 5 is arranged so as to protrude toward the inside of the recess 2d of the receiving pipe portion 2, and thus, between the receiving pipe portion 2 and the insertion pipe portion 3. By uniformly pressing the seal member 4 arranged in the inside of the receiving pipe portion 2, the gap between the inner peripheral surface of the receiving pipe portion 2 and the outer peripheral surface of the insertion pipe portion 3 is evenly distributed in the circumferential direction. When the sealing force of the seal member 4 can be improved, and the external force such as bending acts on the pipe line due to the convex-concave fitting of the protrusion 5a of the push ring 5 and the concave portion 2d of the receiving pipe portion 2. However, it can strongly oppose this external force.

  Next, a plurality of work bolts 17 and nuts 18 arranged along the circumferential direction are sequentially tightened, and the front surface 5c and the back surface 5d of the push wheel 5 are connected to the flange end surface 2c of the socket pipe portion 2 and the insertion pipe. The front surface 3c of the flange portion 3b of the portion 3 is pressed against the front surface 3c, and the sealing member 4 draws the receiving pipe portion 2 and the insertion pipe portion 3 until they are sealed. During this tightening, the temporary fastening member 16, the back surface 3d of the flange portion 3b, the front surface 5c of the push ring 5, the flange end surface 2c of the socket pipe portion 2, the flange portion 2b, etc. are slid to cause an insulation coating layer or rust-proof treatment. , The temporary fastening member 16 is replaced with an insulation-treated fastening member 6 described later, and since the push ring 5 and the socket pipe portion 2 are made of the same material, the insulation performance of the insulating joint structure 1 is improved. Does not affect.

  In addition, since the front surface 5c of the push wheel 5 is in surface contact with the flange end surface 2c of the receiving tube portion 2 in this manner, the insertion tube portion 3, the pushing wheel 5, and the receiving tube portion 2 are connected to each other. You can position the direction.

  After the work piece 17 and the insertion piece 3 have been drawn together by the work bolt 17 and the nut 18, the work piece 17 and the nut 18 are sequentially removed, and a new fastening member 6 is sequentially tightened in place of them. To do. As shown in FIG. 5, the fastening member 6 is composed of a bolt 7, a nut 8, and a pair of insulating washers 9 that are inserted into the shaft portion of the bolt 7, and the bolt 7 in the axial direction thereof. It is inserted through the bolt hole 2h of the flange portion 2b of the socket pipe portion 2, the bolt hole 5h of the push ring 5, and the bolt hole 3h of the flange portion 3b of the insertion pipe portion 3. By doing so, the receiving tube portion 2, the insertion tube portion 3, and the push ring 5 interposed therebetween can be integrated in a state of being positioned by the fastening member 6.

  The insulating washer 9 is composed of a metal ring 9b that contacts the inner end surfaces of the bolt 7 and the nut 8, and an insulating resin ring 9a that contacts the flange portion 2b and the flange portion 3b sandwiched by the fastening member 6. Therefore, the fastening member 6 is fastened in a state where electrical contact with the receiving pipe portion 2 and the insertion pipe portion 3 to be fastened is avoided. The insulating washers 9 may be provided with resin rings 9a on both sides of the metal ring 9b, or may be bolts, nuts or other accessory parts for promoting insulation.

  The tightening control of the plurality of bolts 7 and nuts 8 constituting the fastening member 6 should be carried out with a jig such as a torque wrench if necessary so as not to make the tightening biased in the circumferential direction. (For example, when the nominal diameter of the bolt is M20, 100 N · m) is preferably tightened uniformly. In the insulating joint structure 1 of the first embodiment, when the push ring 5 comes into contact with the flange end surface 2c of the socket tube portion 2 and the front surface 3c of the flange portion 3b of the insertion tube portion 3, the tightening torque rapidly increases. Therefore, it is possible to easily determine the completion of tightening by the feel of tightening without performing tightening by the normal torque management.

  Further, as described above, since the bolt 7 and the nut 8 which are the new fastening members 6 are tightened after the drawing of the receiving pipe portion 2 and the insertion pipe portion 3 by the work bolt 17 and the nut 18 is completed, When the bolt 7 and the nut 8 are fastened, a pulling load such as sliding contact with the receiving pipe portion 2 and the inserting pipe portion 3 is not applied. Therefore, since the fastening member 6 can be fastened as a new product without causing a small scratch or the like due to sliding contact at the time of fastening, the insulation function can be sufficiently exhibited without impairing its insulation function.

  According to the insulating joint structure 1 of the present invention described above, the insertion tube portion 3 has the flange portion 3b formed integrally with the insertion portion 3a and extending in the outer radial direction, and the push ring 5 is Is provided in an insulated state between the flange portion 2b of the receiving pipe portion 2 and the flange portion 3b of the insertion pipe portion 3, and the back surface 5d of the push ring 5 is supported by the flange portion 3b of the insertion pipe portion 3. Further, the fastening member 6 is inserted in an insulated state so as to bridge the flange portion 2b of the receiving pipe portion 2 and the flange portion 3b of the insertion pipe portion 3.

  By doing so, the flange portion 3b that is integrally formed with the insertion opening portion 3a of the insertion opening tube portion 3 that is inserted into the reception opening tube portion 2 is fixed to the flange portion 2b of the reception opening pipe portion 2 by the fastening member 6. Since they are fastened to each other, even if an unexpected external force such as an earthquake or uneven settlement occurs, the inlet pipe section 3 does not bend, and the receiving pipe section 2 and the inserting pipe section 3 are relatively opposed to each other. It is integrated without moving, and while maintaining the high insulation state of both pipe parts, the pressing member 5 supported by the flange portion 3b stably presses the seal member 4 to keep the both pipe parts in a sealed state. Can be held.

  Further, in the present embodiment, since the push ring 5 is a member made of the same metal material as that of the receiving pipe portion 2, as described above, the receiving pipe portion 2 and the insertion pipe portion 3 are provided by interposing the pushing ring 5. When pulling together or when an unexpected external force is generated after completion of piping, for example, the protruding portion 5a of the push ring 5 or a portion in the vicinity thereof and the recessed portion 2d of the receiving pipe portion 2 are in sliding contact with each other. Even when the insulating coating layer D of the push ring 5 is peeled off and electrically contacted at the portion, there is no potential difference between the same metals and galvanic corrosion does not occur. On the other hand, the rear surface 5d of the push wheel 5 and the front surface 3c of the flange portion 3b of the insertion tube portion 3 are in flat contact with each other because there is no concave and convex engagement portion, and thus the surface contact is made. There is no risk that the insulating coating layer D will peel off on the back surface 5d of the push wheel 5. In addition, since the insulating coating layer C is formed on the entire surface of the insertion tube portion 3 except for the other end 3r side, the gap between the insertion tube portion 3 and the push ring 5 which are different metals is formed. Has a double insulating coating layer C and a double insulating coating layer D, so that the insulating performance can be kept high.

  Next, a first modified example of the push ring that constitutes the insulating joint structure of the present invention will be described with reference to FIG. It should be noted that the same configuration as that of the above-mentioned embodiment will not be repeated.

  The push ring 15 of the first modified example has a front surface 15c connected to the inner peripheral surface thereof and extending in a flat surface shape in a direction substantially orthogonal to the tube axis, and a flat surface shape in a direction substantially orthogonal to the tube axis on the side opposite to the front surface 15c. It mainly comprises a back surface 15d extended to the. Further, a plurality of bolt holes 15h penetrating through the front surface 15c and the back surface 15d are provided along the circumferential direction. The inner diameter side of the front surface 15c of the push wheel is configured as a pressing portion that presses the seal member 4.

  By doing so, the front surface 15c of the push wheel 15 and the flange end surface 2c of the receiving tube portion 2 can be brought into flat surface contact over the entire surface. When the part 2 and the insertion tube part 3 are drawn together, or when an unexpected external force is generated after the completion of piping, there is no risk of the insulating coating layer D of the push ring 15 peeling off at the location where the surface abuts.

  Next, a second modified example of the push ring forming the insulating joint structure of the present invention will be described with reference to FIG. It should be noted that the same configuration as that of the above-mentioned embodiment will not be repeated.

  The push ring 25 of the second modified example has a recessed portion 25a as a pressing portion that is connected to the inner peripheral surface thereof and is annularly recessed in one direction of the pipe axis to press the seal member 4, and the outer diameter of the recessed portion 25a. A front surface 25c which is continuous to the side and extends in a direction substantially orthogonal to the tube axis, and a rear surface 25d which extends in a direction substantially orthogonal to the tube axis on the opposite side of the recess 25a and the front surface 25c. Mainly equipped with. Further, a taper surface 25b that gradually extends forward toward the outer diameter side is provided at the front end of the recessed portion 25a in the pipe axis direction, and further, a bolt hole 25h penetrating the front surface 25c and the back surface 25d and penetrating therethrough is circumferentially arranged. Are equipped with multiple. However, the taper surface 25b is not limited to a taper, and may be formed on a surface substantially orthogonal to the tube axis.

  By doing so, the rear end side of the seal member 4 can be housed in the recessed portion 25a positioned outside the flange end surface 2c of the receiving pipe portion 2, so that the seal member 4 becomes excessive. Instead, by pressing with an appropriate pressing force, a uniform elastic repulsive force is generated over the entire surface of the seal member 4, its sealing performance can be exhibited, and the pressing ring 25 can be centered.

  Although the embodiments of the present invention have been described above with reference to the drawings, the specific configurations are not limited to these embodiments, and any modifications or additions within the scope of the present invention are included in the present invention. Be done.

  For example, in the embodiment, the insulating coating layer C is formed on the entire surface of the fluid pipe portion 3p excluding the inner peripheral portion of the inlet portion 3a of the inlet pipe portion 3, the flange portion 3b and its bolt hole 3h, and the other end portion 3r side. However, the present invention is not limited to this, and as shown in FIG. 10, for example, in addition to the insulating coating layer C formed at the above-mentioned location, the outer peripheral surface on the distal end side of the insertion opening 3a, and this outer peripheral surface. A further insulating coating layer F may be formed on the outer surface of the insulating coating layer C covering the distal end surface of the insertion pipe portion 3 connected to the above by rubber vulcanization or adhesion. Further, a spacer such as rubber may be installed on the inner peripheral surface of the receiving tube portion 2.

  Further, for example, in the above-described embodiment, the push ring 5 is a member made of the same metal material as that of the inlet pipe portion 2, but the present invention is not limited to this, and at least the surface thereof has an insulating property, the inlet pipe portion. Different from 2, a member made of the same metal material as the inlet pipe portion 3 may be used, or a member made of a different metal material from both the receiving pipe portion 2 and the inlet pipe portion 3 may be used, or the push ring can withstand the pinching pressure. As long as it has the obtained structural strength, it is not limited to a metal material and may be made of various hard materials.

DESCRIPTION OF SYMBOLS 1 Insulated joint structure 2 Receptacle pipe portion 2a Receptacle portion 2b Collar portion 2c Collar end face 2d Recessed portion 3 Insertion pipe portion 3a Insertion portion 3b Flange portion 3c Front face 3d Rear face 3g Thick portion 4 Seal member 4a Valve portion 4b Covered Pressing surface 5 Pushing wheel 5a Projecting part (pressing part)
5b Tapered surface 5c Front surface 5d Rear surface 6 Fastening member 7 Bolt 8 Nut 9 Insulation washer 15 Push ring 15c Front surface (pressing portion)
16 Temporary fastening member 20 Flexible tube 25 Push ring 25a Recessed portion (pressing portion)
30 Flexible Expansion Pipe Joint (Expansion Joint)
100 fluid lines

Claims (6)

A receiving pipe portion made of a metal material and having a flange portion extending in the outer diameter direction at the opening end, and the receiving pipe portion made of a different metal material and inserted into the receiving pipe portion. An insertion tube part having an insertion part, a seal member for sealing between the receiving tube part and the insertion tube part, a push ring for pressing the sealing member, the receiving tube part and the insertion tube An insulating joint structure comprising at least a fastening member for fastening a portion,
The mouthpiece tube portion has a flange portion that is formed integrally with the mouthpiece portion and extends in the outer diameter direction, and the pusher ring includes the flange portion of the mouthpiece pipe portion and the mouthpiece pipe portion. While being insulated from the flange portion, the back surface of the push wheel is supported by the flange portion of the insertion pipe portion, and the fastening member is the collar portion of the receiving pipe portion. And an insulating joint structure which is inserted in an insulated state so as to extend over the flange portion of the insertion tube portion.   The insulating joint structure according to claim 1, wherein the fastening member is inserted through the push ring in an insulated state.   The insulating joint structure according to claim 1, wherein a rear surface of the push ring is in surface contact with the flange portion of the insertion tube portion.   The insulating joint structure according to any one of claims 1 to 3, wherein a front surface of the push wheel is in surface contact with the flange portion of the receiving pipe portion.   The insulating joint structure according to any one of claims 1 to 4, wherein the push ring has a pressing portion that projects toward the inside of the receiving pipe portion and presses the sealing member.   The insulation joint structure according to any one of claims 1 to 5, wherein an expansion joint having at least elasticity is formed at the other end of the receiving pipe portion or the insertion pipe portion.

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