JP3906376B2 - Plastic joint for piping - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a resin joint for pipes, and more particularly to a resin joint for pipes that keeps the liquid-tightness of a connection portion with pipes and other joints by packing.
[0002]
[Prior art]
As this type of resin joint for piping (hereinafter referred to as “resin joint”), a metal corrugated pipe having an inner surface coating resin layer with a connecting flange attached to the end thereof, or a metal having an inner surface coating resin layer There is known an end portion of a corrugated tube manufactured by joining a cylindrical portion connected to the inner peripheral portion of the flange portion and attaching a connecting flange portion to the cylindrical portion. In both the former and the latter resin joints, the connecting flange part on the resin joint side and the mating flange part provided on the pipe or another joint are brought into contact with each other, and then they are fastened with bolts and nuts. And the flanges are pressed in the direction of approaching each other to connect the resin joint and the pipe or joint. Moreover, in such construction, the liquid tightness of the connection location is maintained by interposing a packing between the connection flange portion and the counterpart flange portion. Conventionally, an independent part made of a disk-shaped resin molded product has been used as the packing.
[0003]
[Problems to be solved by the invention]
However, conventionally, there is not only the trouble that the packing, which is a separate part from the resin joint, must be carried together with the resin joint to the piping construction place, but also the connection flange portion and the counterpart flange of the resin joint. There is a problem that the packing interposed between the two flange portions is displaced during the operation of abutting and tightening the portions, and the connection operation cannot be performed smoothly.
In addition, a gap is inevitably generated between the end portion of the inner surface coating resin layer of the corrugated pipe of the resin joint and the packing at the connection point between the resin joint and the pipe or another joint, and the liquid flowing through the pipe is in the gap. In such a case, the liquid may come into contact with the metal surface of the corrugated tube and corrode the portion. In particular, when the corrugated pipe is corroded in the resin joint for piping, there is a problem that various inconveniences due to the corrosion occur.
[0004]
The present invention has been made in view of the above situation and problems, and eliminates the troublesomeness of bringing the packing as a separate part to the piping construction place together with the resin joint by providing the packing integrally with the resin joint. In addition, another object of the present invention is to provide a resin joint for pipes that has no room for occurrence of a situation where the packing is displaced during the connecting operation of the resin joint.
[0005]
[Means for Solving the Problems]
In the resin joint for piping according to the present invention, a connection flange portion is attached to an end portion of a metal corrugated pipe having an inner surface covering resin layer, and the connection flange portion is abutted against a mating flange portion with a packing interposed therebetween. In the resin joint for piping to be coupled in a state where the flange portions are pressed toward each other, the end portion of the corrugated pipe inserted through the center hole of the connection flange portion is along the outer end surface of the connection flange portion. A face plate portion is extended, and the inner surface coating resin layer is formed on the face plate portion by extending the inner surface coating resin layer, and an additional coating resin layer of the same material as the inner surface coating resin layer is overlapped. A packing main portion that overlaps the outside of the face plate portion provided with a layer and a mounting piece that extends from the packing main portion in a folded shape and overlaps the inside of the face plate portion are integrally provided. With their the packing main portion and the attachment piece portion is held above the packing within the faceplate portion in a form straddling above surface plate portion, is that.
[0006]
According to the present invention, since the packing is held by the face plate portion in a form in which the packing main portion and the mounting piece portion straddle the face plate portion, the packing is used as a separate part during transportation or connection work. Instead, it can be handled with the resin joint. Therefore, the troublesomeness of carrying the packing together with the resin joint to the piping construction place is eliminated, and there is no room for the situation where the packing is displaced during the connection work of the resin joint. Further, the face plate portion extended to the end portion of the corrugated tube has an additional covering resin layer formed by extending the inner surface covering resin layer of the corrugated tube, and on the outside of such face plate portion. Since the packing main part overlaps and the mounting piece that extends from the packing main part overlaps inside the face plate part, it overlaps between the end of the inner surface coating resin layer of the corrugated tube and the packing at the connection point. A situation in which a gap is generated does not occur, so that a situation in which the liquid flowing through the pipe contacts the metal surface of the corrugated pipe and corrodes the portion does not occur.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
1 to 4 show a resin joint for piping according to claim 1, FIG. 1 is a half-side view, FIG. 2 is an enlarged sectional view of a portion II in FIG. 1, and FIG. 3 is a modification of the portion II in FIG. It is the expanded sectional view shown and the expanded sectional view which showed the other modification of the II section of FIG.
[0008]
As shown in FIG. 1, the resin joint A includes a corrugated pipe 1 having a corrugated pipe wall provided with an inner surface covering resin layer 2 (see FIG. 2). One end and the other end of the corrugated tube 1 are provided with a straight tube portion 12 in which the corrugation is omitted. The straight tube portion 12 is inserted into the center hole 31 of the connection flange portion 3, thereby connecting flange portion 3. Is attached to the end of the corrugated tube 1. The corrugated tube 1 is made of a metal tube that is not easily rusted, such as stainless steel. In addition, the inner surface coating resin layer 2 is a synthetic material having excellent chemical resistance such as a fluororesin that is not easily attacked by contact with an acidic liquid such as hydrochloric acid or sulfuric acid, a corrosive liquid such as an alkaline liquid or an organic solvent. Resin is used. The inner surface coating resin layer 2 is formed in a waveform that overlaps the inner surface of the corrugated tube 1. Then, the corrugated tube 1 is integrated with the inner surface coating resin layer 2 so as to exert a reasonable expansion / contraction action or bending deformation action according to a temperature change or the like.
[0009]
As shown in FIG. 2 in an enlarged manner, the straight plate portion 12 of the corrugated tube 1 is extended with a face plate portion 13 along the outer end surface 32 of the connection flange portion 3 through which the straight tube portion 12 is inserted. ing. In the example of FIG. 2, the face plate portion 13 is divided into an inner side face plate portion 14 and an outer side face plate portion 15 that overlap in a folded shape, and the outer peripheral portions of the inner and outer face plate portions 14 and 15 are bent portions 16. Is continuous through. In addition, the entire surface plate portion 13, that is, the inner and outer surface plate portions 14, 15 and the bent portion 16, are overlapped with the additional covering resin layer 21 formed by extending the inner surface covering resin layer 2. The additional coating resin layer 21 is formed of the same resin as the inner surface coating resin layer 2.
[0010]
5 is a packing. The packing 5 includes an annular packing main portion 51 and an annular mounting piece 52 extending outwardly from the inner peripheral portion of the packing main portion 51, and the inner side plate portion of the face plate portion 13. 14 and the outer face plate portion 15 are sandwiched between the packing main portion 51 and the attachment piece portion 52 across the inner side face plate portion 14 so that the packing 5 is attached to the face plate portion 13. Is retained. In addition, an annular cushion material 53 made of leather, cardboard or other material having cushioning properties is sandwiched between the outer side plate portions 15. The packing 5 is made of the same resin as that of the inner coating resin layer 2.
[0011]
The corrugated tube 1 having the inner surface coating resin layer 2 and the additional coating resin layer 21 is manufactured by, for example, the following process. That is, after lining or coating the inner surface coating resin layer 2 or the additional coating resin layer 21 on the inner surface of a metal straight pipe before being formed into a corrugated shape, the straight pipe is shown in FIG. 1 or FIG. 2 using a molding machine. In addition, the face plate portion 13 is formed into a chevron. Then, after the attachment piece 52 of the packing 5 is sandwiched between the inner side plate 14 and the outer side plate 15 of the face plate 13, the inner side plate 14 and the outer side plate 15 of the face plate 13 are crimped. Thus, the mounting piece 52 is firmly held between the face plate portions 14 and 15.
[0012]
When the above-mentioned resin joint A for piping is connected to piping or another joint, the connecting flange portion 3 is abutted with a mating flange portion (not shown) provided in the piping or another joint, and bolts, nuts, etc. The two flange portions are joined by pressing both flange portions toward each other with the fastener.
[0013]
According to this embodiment, since the packing 5 is held by the face plate portion 13 at the end of the corrugated tube 1, the packing 5 is not used as a separate part in the transportation or connection work of the resin joint A. Since it can be handled with the joint A, the troublesomeness of bringing the packing 5 into the piping construction place together with the resin joint A as a separate part is eliminated. Further, since the packing 5 is originally held by the face plate portion 13 of the corrugated tube 1, there is no room for the packing 5 to be displaced during the connecting operation of the resin joint A, and the connecting operation is smoothly performed. Will be able to. Moreover, the face plate part 13 extended to the edge part of the corrugated pipe 1 has the additional coating resin layer 21 formed by extending the inner surface coating resin layer 2 of the corrugated pipe 1, Since the packing main portion 51 overlaps the outside of the face plate portion 13 via the cushion material 53 and the attachment piece portion 52 extending in a folded shape from the packing main portion 51 overlaps the inside of the face plate portion 13, A situation in which a gap is not generated between the end portion of the inner surface coating resin layer 2 of the corrugated tube 1 and the packing 5 does not occur, and therefore a situation in which the portion is corroded does not occur.
[0014]
FIG. 3 shows a modification. In this case, the cushion main part 51 of the packing 5 is directly overlapped with the outer face plate part 15 of the face plate part 13 by omitting the cushion material 53 described in FIG. is there. Other configurations are the same as those described in FIG. 1 or FIG. Therefore, the same or corresponding parts are denoted by the same reference numerals to avoid duplication of explanation.
[0015]
FIG. 4 shows still another modification. In this case, a single face plate portion 13 is extended from the straight tube portion 12 of the corrugated tube 1 along the outer end surface 32 of the connection flange portion 3 through which the straight tube portion 12 is inserted. The packing 5 includes an annular packing main portion 51 and an annular mounting piece portion 52 extending inwardly from the outer peripheral portion of the packing main portion 51, and the face plate portion 13 and the connection flange portion 3. The packing 5 is held by the face plate 13 in such a form that the packing main portion 51 and the attachment piece 52 straddle the face plate 13. An additional covering resin layer 21 formed by extending the inner surface covering resin layer 2 overlaps the entire face plate portion 13. The additional coating resin layer 21 is formed of the same resin as the inner surface coating resin layer 2. Other configurations are the same as those described in FIG. 1 or FIG. Therefore, the same or corresponding parts are denoted by the same reference numerals to avoid duplication of explanation.
[0016]
Even in the case described with reference to FIG. 3 and FIG. 4, the same operation as that described with respect to the embodiment of FIG. 1 or FIG. 2 is exhibited.
[0017]
According to the above embodiment, when the packing 5 is formed of the same resin as the inner surface coating resin layer 2, the fluororesin is not easily eroded even when the outer face plate portion 15 of the face plate portion 13 comes into contact with the corrosive liquid. Can be held by the packing main portion 51 made of synthetic resin having excellent chemical resistance and the inner surface coating resin layer 2 at the end portion of the corrugated tube 1, and the metal tube at the end portion of the corrugated tube 1 can be It can reliably protect against corrosion caused by contact.
[0018]
【The invention's effect】
As described above, in the resin joint for piping according to the present invention, since the packing is originally held on the resin joint side, the trouble of carrying the packing into the piping construction place together with the resin joint as a separate part is eliminated, In addition, the number of parts required for the piping is reduced, so that the cost of the piping can be easily reduced, and there is no room for a situation where the packing is displaced during the connection work, and the connection workability is improved accordingly.
[Brief description of the drawings]
FIG. 1 is a half side view of a piping resin joint according to an embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view of a portion II in FIG.
FIG. 3 is an enlarged cross-sectional view showing a modification of the II part in FIG. 1;
4 is an enlarged cross-sectional view showing another modified example of the II part of FIG. 1. FIG.
[Explanation of symbols]
A resin joint for piping 1 corrugated pipe 2 inner surface covering resin layer 3 connection flange portion 5 packing 6 flange portion 13 face plate portion 21 additional covering resin layer 31 center hole of connection flange portion 32 outer end surface of connection flange portion 51 packing main portion 52 mounting One part

Claims (1)

A connection flange is attached to the end of a metal corrugated tube having an inner surface coating resin layer, and the connection flange is abutted against the mating flange with the packing interposed therebetween, so that both flanges are pressed toward each other. In resin joints for piping that are joined in a
A face plate portion extending along the outer end surface of the connection flange portion is extended to the end portion of the corrugated tube inserted through the center hole of the connection flange portion, and the inner surface covering resin layer is extended to the face plate portion. The additional coating resin layer of the same material as the inner surface coating resin layer is overlapped,
The packing includes a packing main portion that overlaps the outside of the face plate portion provided with the additional coating resin layer, and a mounting piece that extends from the packing main portion in a folded shape and overlaps the inside of the face plate portion. And the packing is held by the face plate portion in a form in which the main packing portion and the attachment piece portion straddle the face plate portion.

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