JP2006292112A - Piping joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a piping joint simple in structure, facilitating attachment of a flange and having excellent pressure tightness. <P>SOLUTION: Both ends of a rubber tubular body 1 with a reinforcing material 5 embedded are provided with thick-walled parts 2 with rigidity. The thick-walled part 2 is structured to embed an annular rigid body 7 wrapped in the end of the reinforcing material 5, in rubber. The flange 3 is externally mounted to the tubular body 1, and an annular fitting 8 is mounted in the tubular body 1. The annular fitting 8 arranged facing the flange 3 is enlarged in diameter on the axially inside of the thick-walled part 2 to fix the flange 3 to the tubular body 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rubber pipe joint that is provided in the middle of a pipe to which a steel pipe or the like is connected and absorbs expansion / contraction, eccentricity, twisting, etc. of the pipe. Specifically, the flange can be easily attached and has excellent pressure resistance. This relates to a pipe joint.

  2. Description of the Related Art Conventionally, as a rubber pipe joint, as shown in FIG. 8, one in which a fitting flange 12 is attached to both ends of a rubber tubular body 11 is known. The rubber tubular body 11 includes an inner layer rubber 13, an outer layer rubber 14, and a reinforcing layer 15 made of a synthetic fiber cord interposed between the inner layer rubber 13 and the outer layer rubber 14 in the entire axial direction. At both ends of the tubular body 11, fitting portions 17 are formed in which a bead ring 16 that is wrapped and wrapped around an end portion of the reinforcing layer 15 is covered with an inner layer rubber 13 and an outer layer rubber 14.

  The fitting portion 17 is formed so as to be fitted to the fitting-type flange 12, and as shown in FIG. 9, the fitting portion 17 is fitted to the flange F of the mating pipe while being fitted to the flange 12. Press contact. Thereby, the pressure P by the flange F acts on the fitting part 17.

  As described above, in the pipe joint, the fitting portion 17 plays a role as a packing material. However, when the flange 12 is bolted, it is difficult to obtain an appropriate and uniform tightening pressure. Has a risk of causing fluid leakage and, if excessive, damage to the fitting portion 17.

  In order to solve the above problem, it is conceivable to use a flange fixing method often used in rubber hoses. That is, as shown in FIG. 10, the non-enlarging outer cylinder 18 is sheathed at both ends of the rubber tubular body 11 in which the reinforcing material layer 15 cut to an arbitrary length is embedded, and is opposed to the outer cylinder 18. The enlarging inner cylinder 19 is provided in the tubular body 11.

  Then, the diameter of the inner cylinder 19 is increased, that is, the outer cylinder 18 is fixed to the tubular body 11 by caulking. Note that the axially outer end of the inner cylinder 19 extends further outward than the end of the tubular body 11, and a flange 21 is externally attached to the extended portion 20. The flange 21 can be fixed to the tubular body 11 by forming a stopper 22 of the flange 21 at the end of the extended portion 20.

  Moreover, as a piping joint which fixes a flange to a tubular body by caulking, the flange formed in the taper shape was used so that the diameter of an internal peripheral surface might become large as it goes to an axial direction outer side like patent document 1. Things are also known. That is, as shown in FIG. 11, this pipe joint is a flange in which a rubber tubular body 11 in which a reinforcing material layer 15 is embedded is cut to an arbitrary length, and inner peripheral surfaces are tapered at both ends thereof. 23 is externally mounted, and a cylindrical fitting 24 is internally mounted on the tubular body 11 so as to face the flange 23.

Then, the end of the tubular body 11 is deformed into a wedge shape so as not to fall out from the flange 23 by expanding and deforming in an inclined shape so that the diameter increases as the cylindrical metal fitting 24 moves inward in the axial direction. .
Japanese Utility Model Publication No. 5-22994

  However, in the piping joint shown in FIG. 10, in order to exhibit stable pressure resistance, it is necessary to enlarge the area of the crimping portion 25, so the axial lengths of the inner cylinder 19 and the outer cylinder 18 are increased. As a result, there is a problem that the axial length of the product becomes large.

  Further, in the pipe joint described in Patent Document 1 shown in FIG. 11, the length of the caulking portion 25 may be shorter than that of the pipe joint shown in FIG. 10, but the tubular body 11 is caused by the pressure of the fluid flowing in the pipe joint. On the other hand, when a force that expands or contracts in the axial direction or a force that expands or contracts in the radial direction acts, the tubular body 11 of the crimping portion 25 becomes thin, and as a result, the tubular body 11 comes out of the flange 23. . The problem of disconnection of the tubular body from the flange due to the fluid pressure has been a problem common not only to the pipe joint described in Patent Document 1, but also to the pipe joint shown in FIG. 9 and the pipe joint shown in FIG. .

  Therefore, an object of the present invention is to provide a pipe joint having a simple structure, easy flange mounting, and excellent pressure resistance.

  In order to solve the above-described problems, the pipe joint according to the present invention is provided with a thick portion having rigidity at both ends of a rubber tubular body in which a reinforcing material is embedded, and the thick portion is an end portion of the reinforcing material. It is structured to embed an annular rigid body embedded in rubber, with a flange mounted on the tubular body, an annular metal fitting inside the tubular body, and the diameter of the annular metal fitting arranged opposite the flange on the inner side in the axial direction of the thick part The flange is fixed to the tubular body.

  According to the above configuration, on the inner side in the axial direction of the thick wall portion, with the flange and the annular fitting placed in the radial direction across the tubular body, the diameter of the annular fitting is increased, that is, the flange is formed by caulking. It can be fixed to a tubular body. Moreover, since the crimped portion obtained by expanding the diameter of the annular metal fitting is formed on the axially inner side of the thick wall portion, the force that expands and contracts in the axial direction with respect to the tubular body due to the fluid pressure applied to the pipe joint. Or even if the force which expands / contracts in a radial direction acts, there is no possibility that a thick part will fall out from a caulking part.

  In the present invention, the axial lengths of the flange and the annular fitting are not particularly limited, and at least all of the flange and the annular fitting are arranged opposite to each other on the inner side in the axial direction of the thick portion, and the annular fitting is in that state. May be expanded.

  For example, the axial length of the flange can be formed so that the end portion on the outer side in the axial direction covers the thick portion, and the axial length of the annular fitting can be the length of only the inner portion in the axial direction of the thick portion. . In this case, the diameter of the entire annular fitting may be increased.

  However, in this case, if the inner peripheral surface of the flange is a smooth surface, the thick portion abuts on the inner peripheral surface of the flange and protrudes inward in the radial direction from the inner peripheral surface of the tubular body. Due to the resistance, there is a risk that it will be worn out and mixed into the fluid in the long term.

  Therefore, in the present invention, it is possible to form a recess at a position corresponding to the thick part of the inner peripheral surface of the flange, whereby the thick part hits the inner peripheral surface of the flange and radially inward from the inner peripheral surface of the tubular body. Protruding can be suppressed.

  In this case, as the annular metal fitting, an annular metal fitting formed such that the end on the outer side in the axial direction covers the thick-walled part can be used, and the entire diameter of the annular metal fitting can be increased. As a result, the thick metal portion can be protruded radially outward from the outer peripheral surface of the tubular body by the annular metal fitting, and can be fitted into the concave portion. Thus, the flange can be more reliably fixed to the tubular body by positively pushing the thick portion into the recess.

  When the flange and the annular metal fitting are used so that the end portion on the outer side in the axial direction covers the thick wall portion, the inner peripheral surface of the flange can be smoothed. In this case, the thick wall portion is in contact with the inner peripheral surface of the flange and is held so as to protrude radially inward from the inner peripheral surface of the tubular body. Only the portion located inside the direction is expanded. Thereby, it becomes possible to fix a flange, protecting a thick part.

  The annular metal fitting can be formed such that an end portion on the outer side in the axial direction is formed up to the end portion of the thick portion, and a protective portion for protecting the thick portion is formed on the end portion. That is, as the annular metal fitting, it is possible to use a member provided with a cylindrical part built in the tubular body and a protective part connected to the end of the cylindrical part, and the protective part is specifically cylindrical. It is possible to use an end portion of which a flange portion is continuously provided outward in the radial direction.

  The annular metal fitting is introduced into the tubular body from the cylindrical part side and inserted until the protective part comes into contact with the thick part. In this state, the thick part can be protected by expanding the diameter of the cylindrical part. That is, by expanding the diameter of the cylindrical portion, the position of the annular fitting with respect to the flange is fixed. Therefore, when the pipe joint according to the present invention is connected to the flange of the mating pipe, the tightening force by the bolt is applied by the protective portion. It is possible to prevent the thick part from being applied directly.

  Moreover, it is also possible to provide a protection part so that it may contact | abut with a flange, and when this connects the piping joint which concerns on this invention to the other party piping, a deformation | transformation of the protection part by a clamping force can be prevented. . In order to contact the protective part and the flange, a protrusion may be formed on the protective part toward the flange, or conversely, a protrusion may be formed on the flange toward the protective part. When the flange portion is formed as the protective portion, the outer peripheral portion of the flange portion may be folded back to the flange side to form a projection portion and contact the flange.

  In the above, the flange mounting structure of the pipe joint has been described, but this flange mounting structure is not only used when mounting the flange of the pipe joint, for example, when mounting a flange at a rubber pipe end, or at a rubber hose end. When attaching a flange etc., it can be used also when attaching a flange to the edge part of a rubber-made tubular body.

  That is, in the present invention, a flange is formed on a tubular body formed of a rubber in which a reinforcing material is embedded, and a thick-walled portion in which an annular rigid body encased in the end of the reinforcing material is embedded in rubber. In addition to the exterior, an annular metal fitting is provided, and the flange and the annular metal fitting are arranged opposite to each other on the inner side in the axial direction of the thick portion, and then the diameter of the annular metal fitting is increased to fix the flange to the tubular body. A method for attaching a flange to a rubber tubular body is provided.

  Further, in the above flange mounting method to the tubular body, the flange and the annular metal fitting are formed such that the end portion on the outer side in the axial direction is applied to the thick portion, and the concave portion is formed at a position corresponding to the thick portion on the inner peripheral surface of the flange. And the thick metal part is protruded radially outward from the outer peripheral surface of the tubular body, and the thick part is fitted into the concave part. .

  Further, the flange and the annular metal fitting are formed such that the end portion on the outer side in the axial direction covers the thick wall portion, the thick wall portion abuts on the inner peripheral surface of the flange, and the radius is larger than the inner peripheral surface of the tubular body. It is hold | maintained so that it may protrude inward of a direction, and it expands a diameter only about the part located in the axial direction inner side of a thick part among cyclic | annular metal fittings.

  In the present invention, a thick-walled portion having rigidity is provided at both end portions of the rubber tubular body, a flange is provided on the tubular body, an annular metal fitting is provided on the tubular body, and opposed to the flange on the axially inner side of the thick-walled portion. Since the diameter of the arranged annular fitting is expanded and the flange is fixed to the tubular body, it is possible to obtain a pipe joint that is easy to attach the flange and has excellent pressure resistance.

[First Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG.1 and FIG.2 is a principal part expanded sectional view which shows 1st Embodiment of the pipe joint which concerns on this invention. As with the rubber pipe joint shown in FIG. 8, the pipe joint according to the present invention is fixed to the rubber tubular body 1 in which the thick wall portions 2 having rigidity are formed at both ends and the both ends of the tubular body 1. The flange 3 is provided. 1 and 2 show one end of the rubber pipe joint, and C shows the central axis of the pipe joint.

  The rubber tubular body 1 is formed by placing a reinforcing member 5 made of a reinforcing cord or the like on the outer surface of an inner layer rubber 4 and covering the outer member with an outer layer rubber 6. The thick portion 2 has a structure in which an annular rigid body 7 wrapped around an end portion of the reinforcing member 5 is covered with an inner layer rubber 4 and an outer layer rubber 6. As the annular rigid body 7, a metal ring, a resin ring, a bead wire, or the like can be used.

  The flange 3 in the present embodiment has an axial length that extends from the inner part A of the thick part 2 to the thick part 2, and has a recess 3 a at a position corresponding to the thick part 2 on the inner peripheral surface of the flange. Is formed. The flange 3 is sheathed on the tubular body 1 so that the concave portion 3a faces the outside in the axial direction, the concave portion 3a is located in the thick portion 2, and the inner peripheral surface other than the concave portion 3a is the inner side in the axial direction of the thick portion 2 It arrange | positions so that it may be located in the part A.

  On the other hand, the annular metal fitting 8 has an axial length that is substantially the same as the inner peripheral surface of the flange 3 positioned in the axially inner portion A of the thick portion 2. The annular fitting 8 is housed in the tubular body 1, and is disposed so as to face the inner peripheral surface of the flange 3 with the tubular body 1 sandwiched in the axially inner portion A of the thick portion 2.

  Then, by expanding the diameter of the entire annular metal fitting 8, the tubular body 1 is pressed against the inner peripheral surface of the flange 3 as shown in FIG. 2, whereby the flange 3 can be fixed to the tubular body 1. At this time, the thick part 2 is accommodated in the recessed part 3a, and thereby, it is possible to suppress the thick part 2 from protruding inward in the radial direction from the inner peripheral surface of the tubular body 1.

[Second Embodiment]
3 and 4 are enlarged cross-sectional views showing a main part of a second embodiment of the pipe joint according to the present invention. In this embodiment, the axial length of the annular metal fitting 8 is from the inner part A of the thick part 2 to the end of the thick part 2, and the flange serves as a protective part that protects the thick part at the end. A feature is that a portion is formed, and the other configuration is the same as that of the first embodiment.

  That is, in this embodiment, as shown in FIG. 3, the annular metal fitting 8 includes a cylindrical portion 8a that is built in the tubular body, and a flange portion 8b that is connected to the end of the cylindrical portion 8a. Then, it is introduced into the tubular body 1 from the cylindrical portion 8 a side and inserted until the flange portion 8 b comes into contact with the thick portion 2. At this time, the axial length of the annular metal fitting 8 is set in advance so that the tip of the cylindrical portion 8 a reaches the axially inner portion A of the thick portion 2.

  And in this state, while expanding the diameter of the whole cylindrical part 8a, while being able to fix the flange 3, the thick part 2 is protruded radially outward from the outer peripheral surface of the tubular body 1, and positively It is possible to fit the recess 3a. Thereby, the flange 3 can be more reliably fixed to the tubular body 1.

[Third Embodiment]
FIG.5 and FIG.6 is a principal part expanded sectional view which shows 3rd Embodiment of the pipe joint which concerns on this invention. In the present embodiment, when the inner peripheral surface of the flange 3 is smoothed and the diameter of the annular metal fitting 8 is increased, only the portion on the inner side in the axial direction of the thick portion 2 is increased. Other configurations are the same as those of the second embodiment.

  That is, in this embodiment, as shown in FIG. 5, since the inner peripheral surface of the flange 3 is smooth, when the flange 3 is externally mounted on the tubular body 1, the thick portion 2 becomes the inner periphery of the flange 3. It is held in contact with the surface so as to protrude radially inward from the inner peripheral surface of the tubular body 1. The outer diameter of the cylindrical portion 8 a of the annular metal fitting 8 is formed to be slightly smaller than the inner diameter of the tubular body 1.

  The annular fitting 8 having the above configuration is inserted until the flange portion 8b contacts the thick portion 2 in the same manner as in the second embodiment. As a result, the tip of the cylindrical portion 8 b reaches the axially inner portion A of the thick portion 2. And in this state, only the part located in the axial direction inner side of the thick part 2 among the cyclic | annular metal fittings 8 is expanded. As a result, as shown in FIG. 6, the flange 3 can be fixed without crushing the thick portion 2.

  As another embodiment of the annular metal fitting 8, as shown in FIG. 7, the outer peripheral portion of the flange portion 8 b is bent to the flange 3 side to form a protruding portion 9, and the protruding portion 9 is brought into contact with the flange 3. It is also possible to do. In this case, good sealing performance is exhibited when the pipe joint according to the present invention is connected to the pipe.

  That is, when the pipe joint according to the present invention is connected to the flange of the mating pipe, the flange portion 8b comes into contact with the mating flange F to seal the inside of the pipe, but when the flange 3 is tightened with a bolt or the like. Further, it is possible to prevent the seal surface 10 from being deformed by the protruding portion 9 and to exhibit a good sealing property.

  A pressure resistance test was performed using the pipe joint produced in the third embodiment. In addition, as a comparative material, three types, the pipe joint (referred to as normal caulking type) shown in FIG. 10, the pipe joint (patent document 1 type) shown in FIG. 11, and the pipe joint (fitting type flange type) shown in FIG. It was used.

  The pressure resistance test was performed by measuring the inter-surface free pressure resistance. That is, as shown in FIG. 12, blind flanges were attached to both ends of a pipe joint S to be a test sample, the inside of the joint S was pressurized with a hydraulic pump P, and the pressure at the time of destruction was measured with a gauge. In the test, the size of each sample was the same (caliber: 100A), and the surface of the sample S could be expanded and contracted freely without being fixed. Table 1 shows the measurement results of the free pressure resistance between the surfaces.

From Table 1, it was found that the pipe joint according to the present invention had higher inter-surface free withstand pressure and superior pressure resistance than any other pipe joint. Note that the pipe joint according to the present invention was tested by confirming that the flange 3 did not fall out of the tubular body 1 even when the pressure in the joint was increased, and that the pressure resistance was 60 kgf / cm ² or more.

The principal part expanded sectional view which shows 1st Embodiment (before flange fixing) of the piping joint of this invention The principal part expanded sectional view which shows 1st Embodiment (after flange fixing) of the piping joint of this invention The principal part expanded sectional view which shows 2nd Embodiment (before flange fixing) of the pipe joint of this invention. The principal part expanded sectional view which shows 2nd Embodiment (after flange fixing) of the pipe joint of this invention. The principal part expanded sectional view which shows 3rd Embodiment (before flange fixing) of the pipe joint of this invention. The principal part expanded sectional view which shows 3rd Embodiment (after flange fixing) of the pipe joint of this invention. Sectional drawing which shows the state which connected the pipe joint of 3rd Embodiment to the other party piping Partial sectional view showing a pipe joint with a conventional fitting flange Fig. 8 is an enlarged view of the main part when the pipe joint of Fig. 8 is connected to the counterpart pipe. The principal part expanded sectional view which shows another aspect of the conventional piping joint The principal part expanded sectional view which shows another aspect of the conventional piping Schematic showing the test content of free pressure resistance between surfaces

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Tubular body 2 Thick part 3 Flange 3a Recessed part 4 Inner layer rubber 5 Reinforcement material 6 Outer layer rubber 7 Annular rigid body 8 Annular metal fitting 8a Cylindrical part 8b Flange part 9 Projection part C Center axis F Flange of mating pipe S Test sample

Claims (9)

A thick-walled portion having rigidity is provided at both end portions of the rubber tubular body in which the reinforcing material is embedded, and the thick-walled portion has a structure in which an annular rigid body wrapped by the end portion of the reinforcing material is embedded in rubber, The tubular body is provided with a flange, the tubular body is provided with an annular metal fitting, the diameter of the annular metal fitting arranged opposite to the flange is increased inside the thick wall portion in the axial direction, and the flange is fixed to the tubular body. Piping joint characterized by 2. The flange according to claim 1, wherein an end portion on the outer side in the axial direction is formed so as to cover the thick portion, and a concave portion is formed at a position corresponding to the thick portion of the inner peripheral surface of the flange. Pipe fittings. The annular metal fitting is formed such that an end portion on the outer side in the axial direction covers the thick wall portion, and by expanding the entire diameter of the annular metal fitting, the thick wall portion is radially outward from the outer peripheral surface of the tubular body. The pipe joint according to claim 2, wherein the pipe joint is held so as to protrude and the thick portion is fitted into the recess. The flange and the annular metal fitting are formed such that an axially outer end portion is applied to the thick wall portion, and the thick wall portion is in contact with the inner peripheral surface of the flange, so that it is more than the inner peripheral surface of the tubular body. 2. The pipe joint according to claim 1, wherein the pipe joint is held so as to protrude inward in the radial direction, and the diameter of only a portion of the annular fitting located on the inner side in the axial direction of the thick portion is increased. The annular metal fitting has an axially outer end formed to the end of the thick portion, and a protective portion for protecting the thick portion is formed at the end. 4. Piping joint according to 4. The pipe joint according to claim 5, wherein the protection portion is provided so as to contact the flange. The flange is externally mounted on a tubular body formed of a rubber having a reinforcing material embedded therein, and a thick-walled portion in which an annular rigid body encased in the end of the reinforcing material is embedded in the rubber. A rubber tube characterized in that the flange is mounted on the inner side in the axial direction of the thick wall portion, and the flange and the annular metal fitting are opposed to each other, and then the diameter of the annular metal fitting is expanded to fix the flange to the tubular body. How to attach the flange to the body. The flange and the annular fitting are formed such that the end portion on the outer side in the axial direction covers the thick wall portion, and a recess is formed at a position corresponding to the thick wall portion of the inner peripheral surface of the flange. 8. The rubber tubular body according to claim 7, wherein the thick-walled portion protrudes radially outward from the outer peripheral surface of the tubular body by being formed into a diameter, and the thick-walled portion is fitted into the concave portion. How to attach the flange to the body. The flange and the annular metal fitting are formed such that an axially outer end portion is applied to the thick wall portion, and the thick wall portion is in contact with the inner peripheral surface of the flange, so that it is more than the inner peripheral surface of the tubular body. The rubber tubular body according to claim 7, wherein the rubber tubular body is held so as to protrude radially inward, and only a portion of the annular fitting located on the axially inner side of the thick portion is expanded. Flange mounting method.

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