JP2006283865A - Pipe joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inner face water shutoff pipe joint capable of positively preventing a phenomenon of a ring coming off. <P>SOLUTION: The pipe joint is structured by a cylindrical joint main body 2 having an attachment groove 21 formed on the outer periphery thereof, and a ring-shaped water shutoff packing 3 made of an elastic material and attached to the attachment groove 21 of the joint main body 2. The joint main body 2 is inserted into a pipe to be connected thereto and and water is shutoff from the pipe and the joint main body 2 by the water shutoff packing 3. The outer diameter of the attachment groove 21 is set bigger than the inner diameter of the water shutoff packing 3 in its initial state so that when the water shutoff packing 3 is attached to the attachment groove 21, the rate of elongation in the peripheral direction of the water shutoff packing 3 is 10 to 30%. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a pipe joint used for connecting pipes.

  Among pipe joints used for connecting pipes, pipe joints for resin pipes mainly made of olefin-based materials have a water-stopping packing provided for waterstop contacting the outer surface of the pipe, or the inner surface of the pipe Depending on whether they are in contact with each other, they are roughly classified into an outer surface still water type and an inner surface still water type.

  Among these, the outer surface still water type pipe joint has a problem that the outer surface of the pipe joint is exposed because the pipe joint is attached to the outer surface of the connecting pipe, and the outer surface of the pipe joint is damaged when handled at the construction site. was there.

  On the other hand, the inner surface water-stop type pipe joint is composed of a cylindrical joint body in which a mounting groove is formed on the outer peripheral surface over the entire circumference, and a water-stop packing that can be mounted in the mounting groove of the joint body. By inserting a pipe joint in which a water stop packing is mounted in the mounting groove of the main body into the connection pipe, the water stop packing is brought into contact with the inner peripheral surface of the connection pipe. Such an inner surface water-stop type pipe joint has been conventionally used without scratching the outer surface of the pipe joint.

Specifically, as shown in FIG. 2, a cylindrical joint body 92 having a mounting groove 921 formed on the outer peripheral surface, and a ring-shaped stopper made of an elastic material mounted in the mounting groove 921 of the joint body 92. A main portion is constituted by the water packing 93, and a pipe joint 91 is described in which the joint main body 92 is inserted into the connection pipe A and the connection pipe A and the joint main body 92 are water-stopped via the water stop packing 93. (For example, refer to Patent Document 1).
JP 2001-295974 A

  Generally, the water stop packing used for a pipe joint is mainly formed of a rubber-based elastic material. And such an elastic material has the property of extending in two directions perpendicular to the direction when compressed in one direction, as shown in FIG. For this reason, in the case of an annular ring-shaped water-stopping seal typified by an O-ring, when the cross section is compressed, elongation occurs in the circumferential direction.

  In addition, flexible pipes formed by extruding materials such as polyethylene, cross-linked polyethylene, and polybutene belonging to olefins among resin pipes are usually supplied as products in a wound state. Then, it cut | disconnects and uses for predetermined length with cutting tools, such as a vinyl chloride cutter. When cutting such a flexible tube, the cut surface is not cut perpendicular to the tube axis, but is often cut obliquely.

  FIGS. 4 to 7 show a case where such a resin connection pipe having a pipe end cut obliquely with respect to the pipe axis is connected to a conventional water-stop type pipe joint.

  Here, an O-ring having a shape defined by JISB2401 is adopted as the water stop packing 93, and a shape / size defined by JISB2406 is adopted as the mounting groove 921 of this O-ring.

First, when the pipe joint 91 is inserted into the connecting pipe A having the pipe end part that is obliquely cut, the tip end part A <b> 1 of the connecting pipe A comes into contact with the water blocking packing 93. At this time, the portion of the water stop packing 93 that comes into contact with the inner peripheral surface of the tip end portion A1 of the connecting pipe A is compressed by receiving a compressive force from the inner peripheral surface of the connecting pipe A (see FIG. 4).

  Then, as the pipe joint 91 is inserted into the connection pipe A, the range in which the inner peripheral surface of the connection pipe A abuts against the water blocking packing 93 is expanded starting from the contact position with the tip end portion A1 of the connection pipe A. The range of the compression seal 93 that receives compression from the inner peripheral surface of the connection pipe A continuously increases (see FIG. 5).

  Thus, the water-stop packing 93 that has received the compressive force sequentially in the circumferential direction expands in the circumferential direction, and finally rises from the mounting groove 921 (see FIG. 6). In such a state, when the end A2 on the opposite side of the distal end A1 of the connecting pipe A comes into contact with the water stop packing 93, the portion of the water stop packing 93 that is lifted from the mounting groove 921 receives a force from the lateral direction. As a result, it is pushed out from the mounting groove 921 and is sandwiched between the inner peripheral surface of the connecting pipe A and the outer peripheral surface of the joint body 92 in the pipe joint 91 (see FIG. 7).

  As a result, a so-called deringing phenomenon occurs in which the water-stopping packing 93 drops from the mounting groove 921, and there is a problem that the water-stopping performance due to the water-stopping packing cannot be exhibited.

  The present invention has been devised in view of such circumstances, and provides an inner surface water-stop type pipe joint capable of reliably preventing the occurrence of a dering phenomenon.

  In order to achieve the above object, a pipe joint according to the present invention includes a cylindrical joint body having a mounting groove formed on the outer peripheral surface thereof, and a ring-shaped stopper made of an elastic material mounted in the mounting groove of the joint body. In a pipe joint that is constructed from a water packing and inserted into a pipe to which the joint body is connected to stop the pipe and the joint body through the water-stopping packing, when the water-stopping packing is mounted in the mounting groove, The outer diameter of the mounting groove is set to be larger than the inner diameter in the initial state of the water-stopping packing so that the circumferential extension ratio of the water-stopping packing is 10 to 30%.

  According to the present invention, the water-stopping packing is stretched in the circumferential direction within a range of 10 to 30% and attached to the outer peripheral surface of the joint body. Is given. Therefore, a pipe joint is inserted into a connecting pipe having a pipe end section that is cut obliquely with respect to the pipe axis, and the inner peripheral surface of the connecting pipe sequentially contacts the water-stopping packing, and is stopped from the abutting inner peripheral surface. Even when the water packing is sequentially subjected to compressive force, the compression amount of the water-stopping packing is further reduced, and even if it extends in the circumferential direction, it floats up from the mounting groove and the inner peripheral surface of the connecting pipe and the pipe It is not sandwiched between the outer peripheral surface of the joint. In this way, the occurrence of the dering phenomenon can be reliably prevented.

  Here, the expansion ratio in the circumferential direction of the water-stopping packing is defined by the extension of the circumferential length of the center of gravity position in the wire diameter cross section of the water-stopping packing. The expansion rate may be set higher as the maximum compression rate of the water stop packing considering the dimensional tolerances of the water stop packing, the mounting groove, and the connecting pipe is higher, and may be set lower when the maximum compression rate is lower.

  Note that the larger the stretch rate is, the more effective it is to prevent de-ringing. However, if the stretch rate exceeds 40%, the water-stopping packing is stretched over a long period of time, so that the rubber material of the water-stopping packing is cut. Therefore, it is desirable to keep the upper limit at 30%. Further, in order to prevent the occurrence of the dering phenomenon and to suitably achieve the water stop purpose, it is desirable that the lower limit of the expansion rate is set to 10% from the design data.

  According to the pipe joint according to the present invention, it has excellent water-stopping properties and can reliably prevent the occurrence of the dering phenomenon.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a pipe joint 1 of the present embodiment with a part thereof broken.

  The pipe joint 1 includes a cylindrical joint body 2 having a mounting groove 21 formed on the outer peripheral surface over the entire circumference, and a ring-shaped water-stopping packing 3 that can be mounted in the mounting groove 21.

  The outer diameter dimension of the mounting groove 21 is set to be larger than the inner diameter dimension in the initial state of the water stop packing 3, and when the water stop packing 3 is mounted in the mounting groove 21, the water stop packing 3 extends in the circumferential direction. It is designed to stretch in the range of 10 to 30%.

  The waterstop packing 3 is formed of a rubber-based elastic material, and an O-ring having a circular cross section is used in this embodiment.

  The water stop packing 3 is not limited to an O-ring, and may be a V packing having a V-shaped cross section, a Z packing having a Z-shaped cross section, or the like.

  The connecting pipe A is mainly an olefin-based resin pipe, and is composed of a flexible pipe formed by extruding a material such as polyethylene, cross-linked polyethylene, polybutene or the like, but is not limited thereto. .

  In Table 1, when an O-ring is used as the water-stopping packing 3, the dimensions of the water-stopping packing 3 when the inner diameter of the connecting pipe A is 9.8 mm, the dimensions of the mounting groove 21, the expansion rate, and the compression rate range Is shown.

  The range of the expansion rate and the compression rate is derived from the dimensional tolerance of the water blocking packing 3 and the mounting groove 21 and the dimensional tolerance of the pipe A.

上記したように本発明に係る管継手１では、止水パッキン３が初期状態よりも円周方向の伸張率が１０ないし３０％の範囲で伸張して継手本体２に装着され、予め円周方向に伸びが与えられている。したがって、管軸に対して斜めに切断された管端部Ａ１を有する接
続管Ａに管継手１を挿入して、止水パッキン３に接続管Ａの内周面が順次当接し、この当接する内周面から止水パッキン３が順次圧縮力を受けた場合であっても、止水パッキン３がさらに圧縮される圧縮量は少なく、円周方向に伸びたとしても、装着溝２１から浮き上がって接続管Ａの内周面と管継手１の外周面との間に挟み込まれることはない。このように、本発明によれば、脱リング現象の発生を確実に防止することができる。

As described above, in the pipe joint 1 according to the present invention, the water-stopping packing 3 is attached to the joint body 2 by extending in the range of 10 to 30% in the circumferential direction from the initial state, and is previously installed in the circumferential direction. The growth is given to. Therefore, the pipe joint 1 is inserted into the connecting pipe A having the pipe end A1 that is cut obliquely with respect to the pipe axis, and the inner peripheral surface of the connecting pipe A sequentially comes into contact with the water blocking packing 3 and comes into contact therewith. Even when the water-stopping packing 3 is sequentially subjected to a compressive force from the inner peripheral surface, the water-stopping packing 3 is further compressed, and even if it extends in the circumferential direction, it floats up from the mounting groove 21. It is not sandwiched between the inner peripheral surface of the connecting pipe A and the outer peripheral surface of the pipe joint 1. Thus, according to the present invention, it is possible to reliably prevent the occurrence of the dering phenomenon.

  The present invention can be applied to a pipe joint that can reliably prevent the dering phenomenon.

It is a side view which fractures | ruptures and shows the pipe joint which concerns on this invention. It is sectional drawing which shows the conventional pipe joint. It is a perspective view explaining the state which compressed the elastic material. (A) is a side view explaining the state which inserts the conventional pipe joint in the connecting pipe of diagonal cutting, (b) is a front view which shows the water stop packing of this pipe joint. (A) is a side view explaining the state which inserts the conventional pipe joint in the connecting pipe of diagonal cutting, (b) is a front view which shows the water stop packing of this pipe joint. (A) is a side view explaining the state which inserts the conventional pipe joint in the connecting pipe of diagonal cutting, (b) is a front view which shows the water stop packing of this pipe joint. It is a side view explaining the state which inserts the conventional pipe joint in the connecting pipe of diagonal cutting.

Explanation of symbols

1 Pipe Fitting 2 Fitting Body 21 Mounting Groove 3 Still Water Seal A Connection Pipe

Claims (1)

It is composed of a cylindrical joint body with a mounting groove formed on the outer peripheral surface, and a ring-shaped water-stopping packing made of an elastic material mounted in the mounting groove of this joint body, and is inserted into a pipe to which the joint body connects In the pipe joint that stops the water through the water sealing packing between the pipe and the joint body,
The outer diameter of the mounting groove is set to be larger than the inner diameter in the initial state of the water-stopping packing so that when the water-stopping packing is mounted in the mounting groove, the circumferential extension rate of the water-stopping packing is 10 to 30%. A pipe joint characterized by being made.

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