JP3939100B2

JP3939100B2 - Earthquake resistant joints and earthquake resistant pipelines

Info

Publication number: JP3939100B2
Application number: JP2001034748A
Authority: JP
Inventors: 敏雄戸島; 貴司横溝
Original assignee: Kubota Corp
Current assignee: Kubota Corp
Priority date: 2001-02-13
Filing date: 2001-02-13
Publication date: 2007-06-27
Anticipated expiration: 2021-02-13
Also published as: JP2002235884A

Description

【０００１】
【発明の属する技術分野】
この発明は、耐震継手ならびに耐震管路に関する。
【０００２】
【従来の技術】
従来、屈曲管路やＴ字状に交叉する管路では、内部流体の水圧によって管路内面に側圧が発生し、このため管路を側方向へ移動させようとするいわゆる不平均力が働く。従って、これら異形管部では継手部が動かないよう、例えば、一定の許容曲げ角度で配管した状態あるいは限界曲げモーメントを負荷した状態で、管径によって水圧１．５ＭＰａ（１５ｋｇｆ／ｃｍ²）〜２．１５ＭＰａ（２２ｋｇｆ／ｃｍ²）を負荷しても漏水せず、また継手も抜け出さない、あるいは、最終的には２．９ＤＫＮ（０．３Ｄ（ｔｆ）：Ｄは呼び径（ｍｍ））の力が作用した場合にも離脱しない性能を有する管継手で相互の管を固定することが行なわれている。
【０００３】
このような性能を満たす管継手として、図９に示したような管継手が開発されている。
すなわち、一方の管１０の管端に形成した受口１に、他方の管１１の挿口２をシール用ゴム輪３を介挿して挿入し、該シール用ゴム輪３を押し輪１４で圧縮するようにした継手であって、前記シール用ゴム輪３より前記受口１奥方側にロックリング４が配設され、該受口１に挿入した前記挿口２の外面における前記ロックリング４より許容脱け出し距離隔てた受口奥方位置に、前記ロックリング４に係り合う周方向突部２ａが形成されてなる耐震継手において、前記受口１の開口面１ｂに取り付けられる押し輪１４内面に、図１０に断面を拡大して示すように係合爪７…７を内面に有する抜け出し防止部材８を、前記挿口２外面から径方向へねじ込まれるセットボルト（図示されていない）などで圧接することによって、通常の水圧負荷ないしは小規模地震等による日常的な地盤変動では、抜け出し防止部材８の爪７の係止力で上記した抜け出し防止性能を発揮するようにし、大地震時では挿口と受口との相対的動きを許容し、前記ロックリングに周方向突部が係り合って抜け出しが防止されるようにしたものである。
【０００４】
しかし、この耐震継手は、小径管の場合は問題がないが、大径管となるほど挿口２の管外面に対する爪７の応力集中が著しくなり挿口外面に傷がつき易くなるといった問題があった。
【０００５】
さらに、大径管の場合、押し輪は二つ割りとされるが、継手部に曲げ力が作用したとき、押し輪の接合部分に生じる曲げ応力が大きくなり、通常の接合片、すなわち単に重ね合わせてボルトで締結するだけの接合片では、強度が不足するおそれがある
【０００６】
【発明が解決しようとする課題】
この発明は、上記問題点を解消し大地震時に挿口と受口との間に相対的移動を許容した場合の抜け出し防止部材による挿口管外周の傷つきを防止すると共に、大きな外力が作用した場合でも押し輪の二つ割り接合部分の強度を十分にすることを課題としてなされたものである。
【０００７】
【課題を解決するための手段】
上記目的を達成するため請求項１の耐震継手は、一方の管の端部に形成された受口の内部に他方の管の端部に形成された挿口をシール用ゴム輪を介挿して挿入し、該シール用ゴム輪を前記受口開口側から押し輪で圧縮するようにした継手であって、前記シール用ゴム輪より前記受口奥方側にロックリングが配設され、該受口に挿入した前記挿口の外面における前記ロックリングより許容脱け出し距離隔てた受口奥方位置に、前記ロックリングに係り合う周方向突部が形成されてなる耐震継手において、
前記押し輪内面には、内面に断面三角形状の複数条の周方向突条を複数条有する抜け出し防止部材が前記挿口外面に圧接可能に配設され、通常の水圧負荷ないしは小規模地震等による日常的な地盤変動ではこの抜け出し防止部材で抜け出し防止が図られ、大地震時では前記抜け出し防止部材によっては、挿口外面に傷を付けることなく挿口と受口との相対的動きが許容され、前記ロックリングに周方向突部が係り合って抜け出しが防止されるようにされ、
また、前記押し輪が二つ割りとされ、かつ該押し輪の周方向接合片の一方が板状片、他方が前記板状片の軸方向面と周方向面とを同時に覆う箱状片とされ、管軸を曲げる方向に外力が加わったとき、接合された一方の板状片が他方の箱状片の周方向面によって曲げ力に対抗できるように支えられる構造とされてなるものである。
【０００８】
即ち請求項１の発明は、受口開口側に抜け出し防止部材を設け、断面形状が三角形とされた複数の周方向突条で応力分散を図りながら挿口外面に係合させるので、大地震時などの外力が作用して、受口と挿口とが相対移動した場合に抜け出し防止部材による挿口管外周の傷つきが防止される。
【０００９】
また、この抜け出し防止部材の設けられる二つ割りの押し輪は、その接合部が一方は板状片、他方は箱状片とされているので、接合した際の両者のずれ許容度が小さく、接合強度も強くなる。
【００１０】
請求項２の耐震管路は、請求項１に記載の耐震継手で構成された管路であって、不平均力の作用する異形管部において、該異形管部を接続する異形管継手が、上記請求項１に記載の耐震継手とされてなるものである。
【００１１】
従って、屈曲管やＴ字状の異形管部における不平均力によっては継手部が移動することはなく、一方、大地震などの大きな外力が作用した場合、継手部が動いて管路の応力緩和が図られると共に、このときの挿口外面の傷つきが防止される。
【００１２】
請求項３の耐震管路は、不平均力の作用する異形管部と他の複数の管体とが接続されて構成される管路の継手が、請求項１に記載の耐震継手とされてなるものである。
【００１３】
従って、屈曲管やＴ字状の異形管部のみならずその周辺の管の継手部も同様に通常時の外力では移動することはなく、大地震などの大きな外力が作用した場合は、継手部が動いて管路の応力緩和が図られると共に、このときの挿口外面の傷つきが防止される。
【００１４】
請求項４の耐震管路は、上記請求項３の耐震管路において、複数の管体に接続される管体の継手が、抜け出し防止リングのない耐震継手であって、受口内面にロックリングが配設され、挿口の周方向突部が前記ロックリングに係合するまで抜け出、あるいは挿口の先端が受口奥方に当接するまで挿入可能とされた耐震継手とされてなるものである。
【００１５】
従って、このような構造としても地盤の変動に応じて耐震継手部が動いて管路の応力緩和が図られる。
【００１６】
【発明の実施の形態】
次に、この発明の実施の形態を説明する。
実施の形態１
図１は、この発明の実施の形態１の耐震継手の断面図、図２は図１の要部拡大図、図３は押し輪の正面図、図４は図３のＢ−Ｂ線矢視で示す、抜け出し防止部材の断面図、図５は図３のＡ−Ａ線矢視拡大図、図６は押し輪接合部の要部斜視図である。
【００１７】
図１において、１は一方の管１０の端部に形成された受口を示し、内面の開口側にシール用ゴム輪３を収納する収納溝３ａと、これより受口１の奥方側にロックリング４を収納するロックリング収納溝５が形成され、これら収納溝３ａにシール用ゴム輪３を、また収納溝５に芯出しゴム６を収納した上でロックリング４が収納されている。
【００１８】
この受口１の内部に他方の管１１の、周方向突部２ａを有する挿口２が前記シール用ゴム輪３およびロックリング４部分を超えて挿入され接続されている。そして、上記耐震継手の受口１の開口側に二つ割りとされた押し輪１４が受口１の開口部のフランジ１ｂにボルト１５で締結され、ナット１５ａを緊締することによりシール用ゴム輪３を受口１内面と挿口２外面との間に圧入しシールされている。
【００１９】
上記押し輪１４の内面には、図２、図３に示ように周方向に嵌合溝１６が形成され、この嵌合溝１６の底面部には外周面から貫通するねじ孔１２が周方向に適宜間隔ごとに複数個所穿設され、嵌合溝１６には抜け出し防止部材１７が収納されている。この抜け出し防止部材１７は、図４に示すように、断面三角形状の周方向突条１７ａ、例えば、高さｈが１．７ｍｍ、底辺の長さｂが１．３〜１．８ｍｍ程度とされた周方向突条１７ａが内面に７〜１０条程度の複数条設けられ、図３に示すように押し輪１４外面からねじ込まれるセットボルト１３で押圧されて挿口２外面に圧接され、この圧接により前記突条１７ａ…１７ａが挿口外面に食い込み、管径によって水圧１．５ＭＰａ（１５ｋｇｆ／ｃｍ²）〜２．１５ＭＰａ（２２ｋｇｆ／ｃｍ²）を負荷しても継手が抜け出すのを防止するようにされている。
【００２０】
なお、この抜け出し防止部材１７は、押し輪１４内面の嵌合溝１６に嵌め込んだ後は落下しないよう、抜け出し防止部材１７間にゴムブロック１７ｂなどを圧縮介挿される。
【００２１】
上記二つ割りの押し輪１４は、図示のように互いに嵌合する接合片１９、２０で接合されるようにされている。
この接合片は図５、図６に示すように、一方の接合片１９は押し輪１４から径方向外側へ延出する舌片状の板状片とされ、他方の接合片２０は、前記接合片１９に対面する板状片２０ａの外周に、前記接合片１９の外周を覆う縁部２０ｂが立設された箱状をなす接合片とされ、互いの対応する位置、例えば中心部分に設けられたねじ孔１９ａ、２０ｃに挿通したボルト（図示省略）にナット（同）を緊締することにより両者を固定するようにされている。
【００２２】
なお、上記実施の形態は、受口１に挿口１１挿入した継手について説明したが、図７に示すような継ぎ輪であっても同様に実施できる。
すなわち、図７は継ぎ輪の断面図を示し、短管１０ａの両端に図１、図２に示した継手部を設けてなるものである。この継手部を有する継ぎ輪を用いることにより不平均力に対する管路の一体化部分で継ぎ輪の使用が可能となる。
【００２３】
なお、図７において図１、図２に示した部材と同一ないしは相当する部材については図１、図２と同じ符号を付し詳細な説明は省略する。
次に、上記耐震継手の作用を説明する。
【００２４】
図１に示すように、受口１に挿入された挿口２は、押し輪１４によって押圧されるシール用ゴム３でシールされる。そして、押し輪１４内面の収納溝１２に収納された抜け出し防止部材１７がセットボルト１３で径方向へ締め付けられ、この締め付け力によって挿口２は受口１内に保持されている。従って、通常時では、この締め付け力により管内水圧等に起因する不平均力により管路が継手部で抜け出したり曲がったりすることがない。
【００２５】
次に、地震など地盤の変動があり、管に伸縮方向や曲げ方向に抜け出し防止部材１７の抜け出し防止力を超える外力が加わると、抜け出し防止部材１７は受口１と挿口２との滑り相対移動を許容する。
【００２６】
このとき、挿口２は、突条１７ａが外面に圧接された状態で軸方向へ移動するがこの突条１７ａは複数条とされ応力分散が図られているため挿口外面に圧接する突条１７ａの応力集中が軽減されるので挿口外面の傷付きが防止される。
【００２７】
そして、挿口突部２ａがロックリング４に係合するまで挿口２が抜け出、あるいは挿口２の先端が受口１の奥方に当接するまで挿入していくことで、地盤の変動による管路に生じる応力が解消される。また、この間、挿口２外面と受口１内面との間はシール用ゴム輪３でシールされたままであるので内部流体が外部へ流出してしまうことはない。
【００２８】
また、一旦継手が動いた後も、挿口２外面と受口１内面との間はシール用ゴム輪３でシールされたままであるのと、抜け出し防止部材１７の残存係止力によって挿口２が受口１から抜け出さない。
【００２９】
以上より明らかなように、不平均力に対する継手として下記のような必要性能を具備する耐震継手が得られる。
（１）下記状態で表１左欄に示すように各径の管路について、右欄に示すような抜け出し防止効果が得られる。
【００３０】
▲１▼ 真っ直ぐの状態。
▲２▼ 許容曲げ角度で配管した場合
▲３▼ 限界曲げモーメントを負荷した場合
【００３１】
【表１】

（２）限界曲げモーメント負荷時に押輪、ボルトナット、爪が破損しない。
（３）抜け出し時に押輪、ボルトナット、爪などの付属品が破損せず、管体に深く傷が付かない。
（４）地震により一度継手が動いた後も、水圧０．７４ＭＰａ（７．５ｋｇｆ／ｃｍ²）で動かず、漏水しない。
（５）最終的には２．９ＤｋＮ（０．３Ｄ（ｔｆ）：Ｄは呼び径（ｍｍ））の力が作用した場合でも抜け出さない。
実施の形態２
図８は、上記の耐震継手を用いた耐震管路の構造図を示す。
【００３２】
図８において、耐震管路２１は、Ｔ字管継手２２を中心として、Ｔ字管継手２２のみあるいはこれらと周辺２〜３個所の継手２３…２３が上記実施の形態１又は２で示した耐震継手とされている。
【００３３】
なお、符号２４で示す継手は通常の耐震継手、即ち、抜け出し防止部材１７のない通常の耐震継手である。
即ち、符号２４で示す管継手は、図１、図２あるいは図７に示した管継手において、抜け出し防止部材１７がなく、このため挿口２の周方向突部２ａがロックリング４に係合するまで挿口２が抜け、あるいは挿口２の先端が受口１の奥方に当接するまで挿入していくことで、地盤の変動による管路に生じる応力が解消される通常の耐震継手とされている。
【００３４】
なお、これら符号２４で示す耐震継手も実施の形態１、２で示した抜け出し防止部材１７を有する耐震継手としても良い。
この実施の形態２の耐震管路では、Ｔ字管継手２２あるいはこれを中心として周辺２〜３個所の継手２３…２３の不平均力の作用する管路部分では、抜け出し防止部材１７による係止力で抜け出し防止力が得られ、大地震時には地盤の変動に応じて継手部が移動し管路に作用する応力を開放する。
【００３５】
従って、これら管路は通常の使用時では完全に鎖構造の管路となり、一方大地震時では継手部が移動しすぐれた耐震性を発揮するのである。
なお、上記実施の形態２の管路として、Ｔ字継手を使用した分岐管路について説明したが、ベンド管を用いた曲管路であって、曲管付近で不平均力が作用する管路であっても同様に実施できる。
【００３６】
【発明の効果】
以上説明したように、請求項１の耐震継手によれば不平均力の働く管路であっても、抜け出し防止部材によって不平均力に対抗する継手固定作用を発揮させながら、管路に大地震などにより過大な外力が作用した場合、挿し口外面に大きな傷をつけることなく、継手部が伸縮移動し応力の緩和を行なうので、耐震管路とすることが可能となる。
【００３７】
また、請求項２の耐震管路によれば、不平均力の作用する管路でありながら耐震構造とされるので、管路の寿命が長く信頼性が高くなる利点を有する。
請求項３、請求項４の耐震管路は、不平均力の作用する異形管のみならずその周辺の管も鎖構造管路とされているものの耐震構造とされるので、管路の寿命が長く信頼性が高くなる利点を有する。
【図面の簡単な説明】
【図１】実施の形態１の耐震継手の要部断面図である。
【図２】図１の要部拡大図である。
【図３】押し輪の正面図である。
【図４】図３のＢ−Ｂ線断面図である。
【図５】図３のＡ−Ａ線断面図である。
【図６】押し輪の接合部分の部分拡大斜視図である。
【図７】実施の形態１の他の構成例を示す断面図である。
【図８】実施の形態２の耐震管路の構成説明図である。
【図９】従来例の要部断面図である。
【図１０】従来の抜け出し防止部材の断面図である。
【符号の説明】
１受口
２挿口
３シール用ゴム輪
４収納溝
５ロックリング収納溝
６芯出しゴム
１０一方の管
１１他方の管
１３セットボルト
１４押し輪
１７抜け出し防止部材
１７ａ突条[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an earthquake resistant joint and an earthquake resistant conduit.
[0002]
[Prior art]
Conventionally, in a bent pipe or a pipe that intersects in a T-shape, a side pressure is generated on the inner surface of the pipe due to the water pressure of the internal fluid, so that a so-called non-average force that moves the pipe in the lateral direction acts. Accordingly, in order to prevent the joint portion from moving in these deformed pipe portions, for example, in a state where piping is performed at a constant allowable bending angle or a limit bending moment is applied, a water pressure of 1.5 MPa (15 kgf / cm ² ) to ² depending on the pipe diameter. Even when a load of .15 MPa (22 kgf / cm ² ) is applied, water does not leak and the joint does not come out, or finally a force of 2.9 DKN (0.3 D (tf): D is the nominal diameter (mm)) It has been practiced to fix the pipes with pipe joints that have the performance of not detaching even when acted upon.
[0003]
As a pipe joint satisfying such performance, a pipe joint as shown in FIG. 9 has been developed.
In other words, the insertion port 2 of the other tube 11 is inserted into the receiving port 1 formed at the tube end of the one tube 10 through the sealing rubber ring 3, and the sealing rubber ring 3 is compressed by the push ring 14. The lock ring 4 is disposed on the back side of the receiving port 1 with respect to the rubber band 3 for sealing, and the joint is made of the lock ring 4 on the outer surface of the insertion port 2 inserted into the receiving port 1. In a seismic joint in which a circumferential protrusion 2a that engages with the lock ring 4 is formed at a position at the back of the receiving port that is separated by an allowable escape distance, an inner surface of a push ring 14 that is attached to the opening surface 1b of the receiving port 1 is provided. As shown in an enlarged cross-sectional view in FIG. 10, a slip-out prevention member 8 having engagement claws 7... 7 on the inner surface is pressed with a set bolt (not shown) that is screwed in the radial direction from the outer surface of the insertion port 2. By normal water pressure load In the case of daily ground changes due to small scale earthquakes, etc., the above-mentioned anti-extraction performance is demonstrated by the locking force of the pawl 7 of the anti-extraction member 8, and the relative movement between the insertion slot and the receiving opening during a large earthquake. And a protrusion in the circumferential direction is engaged with the lock ring to prevent the lock ring from coming out.
[0004]
However, this seismic joint has no problem in the case of a small-diameter pipe, but there is a problem that the larger the diameter of the pipe, the more concentrated the stress of the claw 7 with respect to the outer surface of the tube of the insertion port 2 and the more easily the outer surface of the insertion port is damaged. It was.
[0005]
Furthermore, in the case of a large-diameter pipe, the push ring is divided into two parts. However, when bending force is applied to the joint, the bending stress generated at the joint of the push ring is increased, and a normal joining piece, that is, simply overlapping There is a risk that the strength of the joint piece simply tightened with bolts may be insufficient. [0006]
[Problems to be solved by the invention]
This invention solves the above problems and prevents damage to the outer periphery of the insertion tube due to the slip-out prevention member when relative movement is allowed between the insertion port and the receiving port during a large earthquake, and a large external force is applied. Even in this case, the problem is to make the strength of the split joint portion of the push ring sufficient.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, the seismic joint according to claim 1 is configured such that an insertion opening formed at the end of the other pipe is inserted into a receiving opening formed at the end of one pipe with a rubber ring for sealing. A joint inserted and compressed with a push ring from the opening side of the receiving port, and a lock ring is disposed on the back side of the receiving port from the rubber ring for sealing, and the receiving port In the seismic joint formed by forming a circumferential protrusion engaged with the lock ring at a position at the back of the receiving port that is separated from the lock ring by an allowable escape distance on the outer surface of the insertion port inserted into
On the inner surface of the push ring, a slip-out preventing member having a plurality of circumferential protrusions having a triangular cross-section on the inner surface is disposed so as to be able to be pressed against the outer surface of the insertion port, and is caused by a normal water pressure load or a small scale earthquake. In everyday ground fluctuations, this slip-out prevention member prevents slip-out, and in case of a large earthquake, the slip-out prevention member allows relative movement between the insertion port and the receiving port without damaging the outer surface of the insertion port. , The protrusion in the circumferential direction is engaged with the lock ring to prevent the lock ring from coming out,
Further, the push ring is divided into two, and one of the circumferentially joined pieces of the push ring is a plate-like piece, and the other is a box-like piece that simultaneously covers the axial and circumferential surfaces of the plate-like piece, When an external force is applied in the direction of bending the tube axis, one of the joined plate-like pieces is supported by the circumferential surface of the other box-like piece so that it can resist the bending force.
[0008]
That is, the invention according to claim 1 is provided with a pull-out prevention member on the opening side of the receiving opening, and is engaged with the outer surface of the insertion opening while distributing stress by a plurality of circumferential protrusions having a triangular cross-sectional shape. When an external force such as the above acts and the receiving port and the insertion port move relative to each other, the outer periphery of the insertion tube is prevented from being damaged by the pull-out prevention member.
[0009]
In addition, the split press ring provided with this pull-out prevention member has a joining portion that is a plate-like piece and the other is a box-like piece. Also become stronger.
[0010]
The seismic duct of claim 2 is a pipe constructed of the seismic joint according to claim 1, wherein the deformed pipe joint connecting the deformed pipe sections in the deformed pipe section on which the non-average force acts, The seismic joint according to claim 1 is formed.
[0011]
Therefore, the joint part does not move depending on the non-average force in the bent pipe or the T-shaped deformed pipe part. On the other hand, when a large external force such as a large earthquake is applied, the joint part moves to relieve the stress in the pipe line. At the same time, and damage to the outer surface of the insertion opening is prevented.
[0012]
The seismic duct of claim 3 is a seismic joint according to claim 1 in which a pipe joint configured by connecting a deformed pipe portion on which an unbalanced force acts and a plurality of other pipe bodies is connected. It will be.
[0013]
Therefore, not only bent pipes and T-shaped deformed pipe parts, but also the joint parts of the surrounding pipes are not moved by normal external force in the same way. If a large external force such as a large earthquake is applied, the joint parts Is moved to relieve the stress on the pipe and prevent the outer surface of the insertion port from being damaged.
[0014]
The seismic conduit of claim 4 is the seismic conduit of claim 3, wherein the joints of the pipes connected to the plurality of pipes are seismic joints having no escape prevention ring, and the lock ring is provided on the inner surface of the receiving port. The seismic joint is formed so that it can be inserted until the circumferential protrusion of the insertion port engages with the lock ring, or can be inserted until the tip of the insertion port contacts the back of the receiving port. .
[0015]
Therefore, even in such a structure, the earthquake-resistant joint portion moves according to the ground change, and stress relaxation of the pipe line is achieved.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of the present invention will be described.
Embodiment 1
1 is a cross-sectional view of a seismic joint according to Embodiment 1 of the present invention, FIG. 2 is an enlarged view of a main part of FIG. 1, FIG. 3 is a front view of a push ring, and FIG. 5 is a cross-sectional view of the pull-out prevention member, FIG. 5 is an enlarged view taken along the line A-A in FIG. 3, and FIG.
[0017]
In FIG. 1, reference numeral 1 denotes a receiving port formed at the end of one tube 10, a storage groove 3 a for storing the rubber ring 3 for sealing on the opening side of the inner surface, and a lock to the back side of the receiving port 1 from this. Lock ring storage grooves 5 for storing the rings 4 are formed. The lock ring 4 is stored after the sealing rubber ring 3 is stored in the storage grooves 3 a and the centering rubber 6 is stored in the storage groove 5.
[0018]
An insertion port 2 having a circumferential protrusion 2a of the other tube 11 is inserted and connected to the inside of the receiving port 1 beyond the sealing rubber ring 3 and the lock ring 4 part. A push ring 14 divided into two on the opening side of the receiving port 1 of the earthquake-resistant joint is fastened with a bolt 15 to the flange 1b of the opening of the receiving port 1, and the nut 15a is tightened to tighten the rubber ring 3 for sealing. It is press-fitted and sealed between the inner surface of the receiving port 1 and the outer surface of the insertion port 2.
[0019]
As shown in FIGS. 2 and 3, a fitting groove 16 is formed in the inner surface of the push ring 14 in the circumferential direction, and a screw hole 12 penetrating from the outer circumferential surface is formed in the bottom surface portion of the fitting groove 16 in the circumferential direction. A plurality of holes are drilled at appropriate intervals, and a fitting prevention member 17 is accommodated in the fitting groove 16. As shown in FIG. 4, the slip-out prevention member 17 has a triangular protrusion 17a having a triangular cross section, for example, a height h of 1.7 mm and a base length b of about 1.3 to 1.8 mm. A plurality of about 7-10 strips are provided on the inner surface, and are pressed by the set bolt 13 screwed from the outer surface of the press ring 14 as shown in FIG. the ribs 17a ... 17a bite into the spigot outer surface, the water pressure by the pipe diameter ^{1.5MPa (15kgf / cm 2) ~2.15MPa} (22kgf / cm 2) so as to prevent the joint escape even when loaded with a Has been.
[0020]
A rubber block 17b or the like is compression-inserted between the slip-out prevention members 17 so that the slip-out prevention members 17 do not fall after being fitted into the fitting grooves 16 on the inner surface of the push ring 14.
[0021]
The split push wheel 14 is joined by joining

pieces

19 and 20 which are fitted to each other as shown.
As shown in FIGS. 5 and 6, one joining piece 19 is a tongue-like plate-like piece extending radially outward from the push ring 14, and the other joining piece 20 is the joining piece as shown in FIGS. 5 and 6. The outer periphery of the plate-shaped piece 20a facing the piece 19 is a box-shaped joining piece in which an edge portion 20b covering the outer circumference of the joining piece 19 is erected, and is provided at a position corresponding to each other, for example, at the central portion. Both are fixed by tightening a nut (the same) to a bolt (not shown) inserted through the

screw holes

19a, 20c.
[0022]
In addition, although the said embodiment demonstrated the coupling inserted in the insertion port 11 in the receptacle 1, it can implement similarly even if it is a joint ring as shown in FIG.
That is, FIG. 7 shows a cross-sectional view of the joint ring, and the joint portions shown in FIGS. 1 and 2 are provided at both ends of the short pipe 10a. By using a joint ring having this joint portion, it is possible to use the joint ring at an integral part of the pipe line against the non-average force.
[0023]
In FIG. 7, the same or corresponding members as those shown in FIGS. 1 and 2 are denoted by the same reference numerals as those in FIGS. 1 and 2, and detailed description thereof is omitted.
Next, the operation of the earthquake resistant joint will be described.
[0024]
As shown in FIG. 1, the insertion opening 2 inserted into the receiving opening 1 is sealed with a sealing rubber 3 pressed by a push ring 14. Then, the slip-out preventing member 17 stored in the storage groove 12 on the inner surface of the push ring 14 is tightened in the radial direction by the set bolt 13, and the insertion port 2 is held in the receiving port 1 by this tightening force. Therefore, in normal times, the tightening force prevents the pipe line from being pulled out or bent at the joint due to the non-average force caused by the pipe water pressure or the like.
[0025]
Next, when there is a ground change such as an earthquake and an external force exceeding the pull-out prevention force of the pull-out prevention member 17 is applied to the pipe in the expansion / contraction direction or the bending direction, the slip-out prevention member 17 slides relative to the receiving port 1 and the insertion port 2. Allow movement.
[0026]
At this time, the insertion port 2 moves in the axial direction in a state where the protrusion 17a is pressed against the outer surface. However, since the protrusion 17a has a plurality of lines and stress distribution is achieved, the protrusion is pressed against the outer surface of the insertion hole. Since the stress concentration of 17a is reduced, the outer surface of the insertion opening is prevented from being damaged.
[0027]
By inserting until the insertion port 2 comes out until the insertion port 2a engages with the lock ring 4 or until the tip of the insertion port 2 comes into contact with the back of the receiving port 1, the tube due to the fluctuation of the ground Stress generated in the road is eliminated. During this time, the space between the outer surface of the insertion port 2 and the inner surface of the receiving port 1 remains sealed with the rubber ring 3 for sealing, so that the internal fluid does not flow out to the outside.
[0028]
Further, even after the joint has moved once, the gap between the outer surface of the insertion port 2 and the inner surface of the receiving port 1 remains sealed with the rubber band 3 for sealing, and the insertion port 2 is retained by the remaining locking force of the pull-out prevention member 17. Does not escape from the receptacle 1.
[0029]
As is clear from the above, an earthquake-resistant joint having the following required performance can be obtained as a joint for non-average forces.
(1) With the following conditions, as shown in the left column of Table 1, the pull-out prevention effect as shown in the right column can be obtained for the pipes of each diameter.
[0030]
(1) Straight state.
(2) When piping at an allowable bending angle (3) When a critical bending moment is applied [0031]
[Table 1]

(2) The push ring, bolts, nuts and claws will not be damaged when a critical bending moment is applied.
(3) Accessories such as push wheels, bolts, nuts and claws will not be damaged when pulled out, and the tube will not be deeply damaged.
(4) Even after the joint has moved once due to an earthquake, it does not move at a water pressure of 0.74 MPa (7.5 kgf / cm ² ) and does not leak.
(5) Eventually, even when a force of 2.9 DkN (0.3 D (tf): D is a nominal diameter (mm)) is applied, it does not come out.
Embodiment 2
FIG. 8 shows a structural diagram of a seismic duct using the seismic joint.
[0032]
In FIG. 8, the seismic duct 21 has the T-shaped pipe joint 22 as a center, and only the T-shaped pipe joint 22 or the joints 23... It is a joint.
[0033]
Note that the joint denoted by reference numeral 24 is a normal earthquake-resistant joint, that is, a normal earthquake-resistant joint without the pull-out preventing member 17.
That is, the pipe joint denoted by reference numeral 24 does not have the pull-out prevention member 17 in the pipe joint shown in FIG. 1, FIG. 2 or FIG. 7, so that the circumferential protrusion 2 a of the insertion port 2 is engaged with the lock ring 4. Until the insertion port 2 is removed until the tip of the insertion port 2 comes into contact with the back of the receiving port 1 until it is inserted, and the stress generated in the pipe line due to ground fluctuation is eliminated. ing.
[0034]
The earthquake-resistant joint indicated by reference numeral 24 may also be an earthquake-resistant joint having the pull-out preventing member 17 shown in the first and second embodiments.
In the seismic duct of the second embodiment, the T-shaped pipe joint 22 or the pipe part where the average force of the joints 23... Pull-out prevention force can be obtained by force, and during a large earthquake, the joint moves according to the ground fluctuation and releases the stress acting on the pipeline.
[0035]
Therefore, these pipes are completely chain-structured pipes during normal use, and on the other hand, in the event of a large earthquake, the joints move and exhibit excellent earthquake resistance.
In addition, although the branched pipe line using the T-shaped joint has been described as the pipe line of the second embodiment, it is a curved pipe line using a bend pipe, and a pipe line on which a non-average force acts near the curved pipe. However, it can be similarly implemented.
[0036]
【The invention's effect】
As described above, according to the earthquake-resistant joint of claim 1, even if the pipe works with an average force, the pipe is subjected to a large earthquake while exhibiting the joint fixing action against the non-average force by the pull-out prevention member. When an excessive external force is applied due to the above, the joint portion expands and contracts and relieves stress without causing a large damage to the outer surface of the insertion slot.
[0037]
Moreover, according to the earthquake resistant pipe of claim 2, since it is an earthquake resistant structure although it is a pipe where the non-average force acts, there is an advantage that the life of the pipe is long and the reliability is high.
The earthquake resistant pipes of claim 3 and claim 4 are not only deformed pipes with non-average forces, but also the surrounding pipes are chain structure pipes. It has the advantage of long and high reliability.
[Brief description of the drawings]
1 is a cross-sectional view of a main part of a seismic joint according to Embodiment 1. FIG.
FIG. 2 is an enlarged view of a main part of FIG.
FIG. 3 is a front view of a push ring.
4 is a cross-sectional view taken along line BB in FIG.
5 is a cross-sectional view taken along line AA in FIG.
FIG. 6 is a partially enlarged perspective view of a joint portion of a push ring.
7 is a cross-sectional view illustrating another configuration example of the first embodiment. FIG.
FIG. 8 is a configuration explanatory diagram of a seismic duct according to a second embodiment.
FIG. 9 is a cross-sectional view of a main part of a conventional example.
FIG. 10 is a cross-sectional view of a conventional pull-out prevention member.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Receptacle 2 Insertion 3 Sealing rubber ring 4 Storage groove 5 Lock ring storage groove 6 Centering rubber 10 One pipe 11 The other pipe 13 Set bolt 14 Push ring 17 Pull-out prevention member 17a Projection

Claims

An insertion port formed at the end of the other tube is inserted into a receiving port formed at the end of one tube through a rubber ring for sealing, and the rubber ring for sealing is inserted into the receiving port side. A joint that is compressed by a push ring, and a lock ring is provided on the back side of the receiving port from the rubber ring for sealing, and is more allowable than the lock ring on the outer surface of the insertion port that is inserted into the receiving port. In the seismic joint formed by forming a circumferential protrusion engaged with the lock ring at a position at the back of the receiving opening that is separated from the escape distance,
On the inner surface of the press ring, a slip-out prevention member having a plurality of circumferential protrusions having a triangular cross section on the inner surface is disposed so as to be able to press contact with the outer surface of the insertion opening, and is caused by a normal water pressure load or a small scale earthquake. In everyday ground fluctuations, this slip-out prevention member prevents slip-out, and in case of a large earthquake, the slip-out prevention member allows relative movement between the insertion port and the receiving port without damaging the outer surface of the insertion port. , The protrusion in the circumferential direction is engaged with the lock ring to prevent the lock ring from coming out,
Further, the push ring is divided into two, and one of the circumferentially joined pieces of the push ring is a plate-like piece, and the other is a box-like piece that simultaneously covers the axial and circumferential surfaces of the plate-like piece, An anti-seismic joint having a structure in which, when an external force is applied in the direction of bending the tube axis, the joined plate-like piece is supported by the circumferential surface of the other box-like piece so that it can resist the bending force.

The deformed pipe part to which the non-average force acts is an earthquake-resistant pipe formed by connecting the deformed pipe part to the earthquake-resistant joint according to claim 1.

A seismic resistant pipe formed by connecting the deformed pipe portion on which the non-average force acts and a plurality of other pipe bodies to the seismic joint according to claim 1.

The seismic conduit according to claim 3, wherein the joint of the pipe connected to the plurality of pipes is a seismic joint without a slip-out preventing ring, and a lock ring is disposed on the inner surface of the receiving port, and the circumferential direction of the insertion port An earthquake-resistant conduit formed as an earthquake-resistant joint that can be inserted until the protrusion is engaged with the lock ring or the tip of the insertion port contacts the back of the receiving port.