JP3838897B2

JP3838897B2 - Method of attaching antirust bush to pipe branch port and pipe joint used therefor

Info

Publication number: JP3838897B2
Application number: JP2001317923A
Authority: JP
Inventors: 功明小林
Original assignee: Waterworks Technology Development Organization Co Ltd
Current assignee: Waterworks Technology Development Organization Co Ltd
Priority date: 2001-10-16
Filing date: 2001-10-16
Publication date: 2006-10-25
Anticipated expiration: 2021-10-16
Also published as: JP2003120882A

Description

【０００１】
【発明の属する技術分野】
本発明は、水道管等の流体輸送管の外周面に、それとの間にシール材を介装した状態で分岐管部を備えた管継手を外装固定し、この管継手の分岐管部側に取付けた穿孔機のカッターにより、分岐管部内を通してシール材で密封された管壁部に分岐口を貫通形成したのち、この分岐口に臨む管壁部の孔内周面に防錆ブッシュを密着状態で装着する管分岐口への防錆ブッシュの取付け方法、及び、それに用いられる管継手の改良に関する。
【０００２】
【従来の技術】
一般に、流体輸送管に貫通形成された分岐口は、防蝕・防錆のためのライニング処理が施されている他の部位に比して腐蝕・発錆し易いため、耐蝕性・耐錆性に優れた防錆ブッシュを分岐口に装着する方法が採用されている。
そして、従来の防錆ブッシュの取付け方法では、図１４示すように、流体輸送管１に、これの管壁部に貫通形成される分岐口４に連通可能な分岐管部２を備えた管継手Ａを、流体輸送管１の外周面との間にシール材３を介装した状態で外装固定し、この管継手Ａの分岐管部２の端部に、作業用開閉弁Ｂ及び穿孔機（図示せず）を順次固定連結し、穿孔機のカッターにより、開き操作された作業用開閉弁Ｂ及び管継手Ａの分岐管２を通して、流体輸送管１内の流体の流れを維持したままシール材３で密封された管壁部に分岐口４を貫通形成したのち、閉止操作された作業用開閉弁Ｂから穿孔機を取り外す。
【０００３】
次に、作業用開閉弁Ｂに、流体輸送管１の分岐口４に嵌入自在な外径に構成された円筒状の防錆ブッシュ５を外套状態で装着する円柱状の弾性体５０と、該弾性体５０を挿通支持する挿入軸５１と、該挿入軸５１に摺動自在に外嵌され、かつ、挿入軸５１の先端部に形成された第１挟圧体５１Ａとの間で弾性体５０を圧縮するための第２挟圧体５２Ａを形成してある押圧筒軸５２とを備えたブッシュ挿入機Ｈを取付け、このブッシュ挿入機Ｈの弾性体５０に装着した防錆ブッシュ５を、開き操作された作業用開閉弁Ｂ、及び、管継手Ａの分岐管部２内を通して流体輸送管１の分岐口４の所定装着位置に挿入したのち、挿入軸５１の第１挟圧体５１Ａと押圧筒軸５２の第２挟圧体５２Ａとの間で弾性体５０を圧縮して径方向外方に膨出させることにより、防錆ブッシュ５を分岐口４の開口周縁に抜止め状態に係合するまで変形させて取付けていた（例えば、特公昭５７−１２９１６号公報、特公昭６１−４２１５８号公報参照）。
【０００４】
【発明が解決しようとする課題】
従来方法では、穿孔機で穿孔された分岐口４に防錆ブッシュ５を装着する場合、作業用開閉弁Ｂにブッシュ挿入機Ｈを取付ける工程、作業用開閉弁Ｂを開き操作する工程、ブッシュ挿入機Ｈの弾性体５０に装着した防錆ブッシュ５を、開き操作された作業用開閉弁Ｂ、及び、管継手Ａの分岐管部２内を通して流体輸送管１の分岐口４に挿入する工程、所定装着位置に挿入された防錆ブッシュ５を分岐口４の開口周縁に抜止め係合させるまで変形させる工程、弾性体５０を待機位置にまで戻す工程、作業用開閉弁Ｂを閉じ操作する工程、作業用開閉弁Ｂからブッシュ挿入機Ｈを取外す工程が必要で、ブッシュ装着作業に多大の労力と手間を要し、しかも、施工に当っては大きなブッシュ挿入機Ｈを準備する必要があるとともに、穿孔機を取外してからでないと、ブッシュ挿入機Ｈを取付けることができないため、工期の長期化と施工コストの高騰化を招来し易い。
【０００５】
本発明は、上述の実状に鑑みて為されたものであって、その主たる課題は、防錆ブッシュの装着作業を穿孔作業完了後の任意の時期に行なうことができ、しかも、防錆ブッシュの装着作業に要する作業工程数及び労力を削減して、工期の短縮化と施工コストの低廉化とを図ることのできる管分岐口への防錆ブッシュの取付け方法及びそれに用いられる管継手を提供する点にある。
【０００６】
【課題を解決するための手段】
本発明の請求項１による特徴構成は、流体輸送管の外周面に、それとの間にシール材を介装した状態で分岐管部を備えた管継手を外装固定し、この管継手の分岐管部側に取付けた穿孔機のカッターにより、分岐管部内を通してシール材で密封された管壁部に分岐口を貫通形成したのち、この分岐口に臨む管壁部の孔内周面に防錆ブッシュを密着状態で装着する管分岐口への防錆ブッシュの取付け方法であって、
管継手の分岐管部内に、管壁部の孔内周面に弾性復元力で密着装着可能で、かつ、分岐口を形成する穿孔機のカッターの通過移動を許容する拡径状態から分岐口に挿入装着可能な縮径状態に弾性変形可能な防錆ブッシュを、拡径状態で予め組付けるとともに、穿孔機のカッターによる穿孔後に、管継手に設けた縮径操作手段によって、拡径状態にある防錆ブッシュを縮径状態に操作したのち、縮径状態にある防錆ブッシュを押込み手段で分岐口の所定装着位置に押込み、縮径操作手段による縮径操作力を解除して、防錆ブッシュの弾性復元力で管壁部の孔内周面に密着させるように構成した点にある。
【０００７】
上記特徴構成によれば、穿孔機のカッターによる穿孔前に、管継手の分岐管部内に、カッターの通過移動を許容する拡径状態で防錆ブッシュを予め組付け、この管継手を、流体輸送管の外周面にシール材を介装した状態で外装固定したのち、管継手の分岐管部側に取付けた穿孔機のカッターにより、分岐管部内の防錆ブッシュを通してシール材で密封された管壁部に分岐口を貫通形成する。
【０００８】
そして、穿孔機のカッターによる穿孔後で、かつ、少なくともカッターが防錆ブッシュから引抜かれた時点以降において、管継手に設けた縮径操作手段によって、拡径状態にある防錆ブッシュを、それの弾性復元力に抗して分岐口に挿入装着可能な縮径状態に操作したのち、この縮径状態にある防錆ブッシュを押込み手段で分岐口の所定装着位置に押込み、その状態で縮径操作手段による縮径操作力を解除すると、防錆ブッシュが弾性復元力で拡径側に弾性変形し、防錆ブッシュの外周面が分岐口に臨む管壁部の孔内周面に弾性復元力で被覆密着して、管壁部の孔内周面の腐蝕、発錆を抑制することができる。
【０００９】
従って、従来工法に比較して作業工程数及び労力を大幅に減少することができるとともに、大きなブッシュ挿入機を準備する必要も無く、しかも、防錆ブッシュの装着作業の開始時期も、穿孔機のカッターによる穿孔後で、かつ、少なくともカッターが防錆ブッシュから引抜かれた時点以降であれば、何時でも行なうことができるから、作業工程計画の制約が少なくなり、工期の短縮化と施工コストの低廉化とを図ることができる。
【００１０】
本発明の請求項２による管分岐口への防錆ブッシュの取付け方法の特徴構成は、前記防錆ブッシュの後端部に、縮径状態において穿孔機のカッターと穿孔軸線方向から接当する受け部が形成されているとともに、前記押込み手段が、穿孔機のカッターをもって兼用構成されている点にある。
【００１１】
上記特徴構成によれば、穿孔機のカッターによる穿孔後で、かつ、少なくともカッターが防錆ブッシュから引抜かれた時点以降において、管継手に設けた縮径操作手段によって、拡径状態にある防錆ブッシュを、それの弾性復元力に抗して分岐口に挿入装着可能な縮径状態に操作したのち、押込み手段を兼用構成する穿孔機のカッターを流体輸送管側に再移動させると、このカッターの先端が、縮径状態にある防錆ブッシュの受け部に穿孔軸線方向から接当し、防錆ブッシュが分岐口の所定装着位置に押し込まれる。
【００１２】
従って、押込み手段を構成するための特別な構造が不要で、しかも、穿孔機の送り機構を利用して防錆ブッシュを分岐口の所定装着位置に押し込むことができるから、管継手構造の簡素化と施工コストの低廉化のみならず、工期の短縮化と労力の軽減化とを図ることができる。
【００１３】
本発明の請求項３による特徴構成は、流体輸送管に対してそれの外周面との間にシール材を介装した状態で外装固定される継手本体に、シール材で密封された管壁部に貫通形成される分岐口に連通可能な分岐管部が形成されている管継手であって、
前記分岐管部内に、分岐口に臨む管壁部の孔内周面に弾性復元力で密着装着可能で、かつ、分岐口よりも大径となる拡径状態から分岐口に挿入装着可能な縮径状態に弾性変形可能な防錆ブッシュが、拡径状態で組付けられているとともに、前記継手本体には、拡径状態にある防錆ブッシュを縮径状態に操作する縮径操作手段と、縮径状態にある防錆ブッシュを分岐口の所定装着位置に穿孔軸線方向から押し込む押込み手段とが設けられている点にある。
【００１４】
上記特徴構成によれば、継手本体の分岐管部内に、流体輸送管に形成される分岐口よりも大径となる拡径状態で防錆ブッシュを予め組付け、この継手本体を、流体輸送管の外周面にシール材を介装した状態で外装固定したのち、継手本体の分岐管部側に取付けた穿孔機のカッターにより、分岐管部内の防錆ブッシュを通してシール材で密封された管壁部に分岐口を貫通形成する。
【００１５】
そして、穿孔機のカッターによる穿孔後で、かつ、少なくともカッターが防錆ブッシュから引抜かれた時点以降において、継手本体に設けた縮径操作手段によって、拡径状態にある防錆ブッシュを、それの弾性復元力に抗して分岐口に挿入装着可能な縮径状態に操作したのち、この縮径状態にある防錆ブッシュを、継手本体に設けた押込み手段で分岐口の所定装着位置に押込み、その状態で縮径操作手段による縮径操作力を解除すると、防錆ブッシュが弾性復元力で拡径側に弾性変形し、防錆ブッシュの外周面が分岐口に臨む管壁部の孔内周面に弾性復元力で被覆密着して、管壁部の孔内周面の腐蝕、発錆を抑制することができる。
【００１６】
従って、従来工法に比較して作業工程数及び労力を大幅に減少することができるとともに、大きなブッシュ挿入機を準備する必要も無く、しかも、防錆ブッシュの装着作業の開始時期も、穿孔機のカッターによる穿孔後で、かつ、少なくともカッターが防錆ブッシュから引抜かれた時点以降であれば、何時でも行なうことができるから、作業工程計画の制約が少なく、かつ、防錆ブッシュの装着作業と穿孔機の取外し作業とを並行して行なうことも可能となり、工期の短縮化と施工コストの低廉化とを図ることができる。
【００１７】
本発明の請求項４による管継手の特徴構成は、前記分岐管部の内壁部と防錆ブッシュとの径方向で対向する部位に、防錆ブッシュの先端部が流体輸送管の外周面から離れた待機位置で、かつ、分岐管部と同芯又はほぼ同芯状態に仮止め保持する仮止め手段が設けられている点にある。
【００１８】
上記特徴構成によれば、流体輸送管に継手本体を外装固定するとき、或いは、穿孔機の取付け時等の振動によって、分岐管部内に予め組付けられた防錆ブッシュが待機位置から穿孔軸芯方向にずれ動いたり、分岐管部の軸芯に対して防錆ブッシュの軸芯が径方向にずれ動くことを抑制して、穿孔作業やブッシュ装着作業の能率化、確実化を図ることができる。
【００１９】
本発明の請求項５による管継手の特徴構成は、前記押込み手段に、分岐管部内に設けられた防錆ブッシュの後端部を分岐口側に押圧する押圧部が設けられていて、防錆ブッシュを分岐口の所定装着位置に押込んだ操作位置で押圧部を固定するロック手段が設けられている点にある。
【００２０】
上記特徴構成によれば、縮径状態にある防錆ブッシュの後端部を、継手本体に設けた押込み手段の押圧部で分岐口の所定装着位置に押込み、その状態で縮径操作手段による縮径操作力を解除して、防錆ブッシュの外周面を分岐口に臨む管壁部の孔内周面に弾性復元力で被覆密着させたのち、その押込み操作位置にある押圧部をロック手段で固定することにより、押込み後に不要となる押圧部を、防錆ブッシュの抜止め部材に用いることができる。
【００２１】
従って、防錆ブッシュを分岐口の所定装着位置に強固に保持することができるとともに、そのための抜止め構造も、押込み手段の押圧部を利用して簡単かつ製造コスト面で有利に構成することができる。
【００２２】
本発明の請求項６による管継手の特徴構成は、前記押込み手段に、分岐管部内に設けられた防錆ブッシュの後端部を分岐口側に押圧する押圧作用位置と、防錆ブッシュの外周面よりも径方向外方に移動させた格納位置とに切換え可能な押圧部が設けられている点にある。
【００２３】
上記特徴構成によれば、縮径状態にある防錆ブッシュを、継手本体に設けた押込み手段で分岐口の所定装着位置に押込む際、穿孔機による穿孔作業の邪魔にならない格納位置にあった押込み手段の押圧部を、径方向内方の押圧作用位置に移動させて、その位置で押込み操作するだけであるから、防錆ブッシュの装着作業を能率良く容易に行なうことができる。
【００２４】
本発明の請求項７による管継手の特徴構成は、前記仮止め手段が、分岐管部の内壁部に形成された係合凹部と、該係合凹部に係合して分岐管部と防錆ブッシュとの穿孔軸線方向での相対移動を規制し、かつ、一定以上の操作力が加えられたときに係合凹部を通過移動可能な状態で防錆ブッシュに形成された係合凸部とから構成されている点にある。
【００２５】
上記特徴構成によれば、分岐管部の内壁部と防錆ブッシュとの径方向で相対向する部位に係合凹部と係合凸部とを形成するだけであるから、防錆ブッシュを待機位置で同芯又はほぼ同芯状態に仮止め保持するための仮止め手段を、構造面及び製造コスト面で有利に構成することができる。
【００２６】
本発明の請求項８による管継手の特徴構成は、前記仮止め手段の係合凸部が、防錆ブッシュを分岐口の所定装着位置に押込んだとき、流体輸送管の分岐口周縁に穿孔軸線方向から接当する当り部に構成されている点にある。
【００２７】
上記特徴構成によれば、仮止め手段を構成する防錆ブッシュ側の係合凸部を利用して、防錆ブッシュが分岐口の所定装着位置に押込まれたとき、流体輸送管の分岐口周縁に接当してそれ以上の押込みを阻止する当り部に構成してあるから、防錆ブッシュの押込み量を規制する特別なストッパーを別途設ける必要が無く、構造の簡素化と製造コストの低廉化とを促進することができる。
【００２８】
本発明の請求項９による管継手の特徴構成は、前記防錆ブッシュが、周方向の一箇所が切断された円筒状に構成され、それの両端部には、拡径状態から縮径状態への弾性変形に連れて重合状態に移動案内するカム面が形成されているとともに、前記防錆ブッシュが装着状態にあるとき、前記両端部のカム面同士が接当して外周面が分岐口の内径に相当する真円形状又は略真円形状になるように構成されている点にある。
上記特徴構成によれば、防錆ブッシュの両端部に形成されたカム面により、拡径状態から縮径状態までの弾性変形を円滑に行なわせながらも、防錆ブッシュが分岐口に装着された状態では、カム面同士が接当して、それの外周面が分岐口の内径に相当する真円形状又は略真円形状になるから、防錆ブッシュの外周面が分岐口に臨む管壁部の孔内周面に弾性復元力で良好に被覆密着して、管壁部の孔内周面の腐蝕、発錆を効果的に抑制することができる。
【００２９】
【発明の実施の形態】
〔第１実施形態〕
図１〜図９は、鋳鉄管や鋼管等から構成される水道管等の既設の流体輸送管１の外周面に、流体輸送管１の管軸芯Ｘに対して交差（当該実施形態では直交）する水平又は略水平方向（穿孔軸線Ｙ方向）に沿って外方に突出する分岐管部２を一体形成してある鋳鉄製の管継手Ａを、流体輸送管１の外周面との間をシール材３で密封（液密又は気密状態に密封）した状態で外装固定し、この管継手Ａの分岐管部２に作業用開閉弁Ｂを介して取付けた穿孔機Ｃのカッター９により、開き操作された作業用開閉弁Ｂ及び分岐管部２内を通して、流体輸送管１内の流体の流れを維持したままシール材（弾性パッキン）３で密封された管壁部に分岐口４を貫通形成したのち、この分岐口４に臨む管壁部の孔内周面１ａに、耐蝕性・耐錆性に優れたステンレス鋼製の防錆ブッシュ５を密着状態で装着する取付け方法を示す。
【００３０】
この管分岐口への防錆ブッシュ５の取付け方法に用いられる管継手Ａの継手本体６は、図１〜図５に示すように、流体輸送管１に対して管径方向の外方から外装自在な管周方向で複数に分割（当該実施形態では三分割）された部分円筒状の分割ケース体６Ａ〜６Ｃから構成されていて、各分割ケース体６Ａ〜６Ｃの管周方向両端部には、流体輸送管１に外装された隣接分割ケース体６Ａ〜６Ｃ同士を締結手段の一例である複数本のボルト７・ナット８で脱着自在に固定連結するための連結フランジ部６ａ〜６ｃが一体形成されているとともに、各分割ケース体６Ａ〜６Ｃの内周面に形成されたシール保持溝６ｄには、流体輸送管１の外周面との間を密封する合成ゴム製（例えば、スチレンブタジエンゴム等）のシール材３が装着されている。
【００３１】
また、一つの分割ケース体６Ａの管軸芯Ｘ方向中央部で、かつ、管周方向の中央部には、前記分岐管部２が一体的に突出形成されているとともに、この分岐管部２の先端に一体形成された連結フランジ部２ａには、作業用開閉弁Ｂの弁ケース１０の一端に一体形成された連結フランジ部１０ａが、締結手段の一例である複数本のボルト７を介して脱着自在に固定連結されている。
【００３２】
前記管継手Ａの分岐管部２内には、分岐口４に臨む管壁部の孔内周面１ａに弾性復元力で密着装着可能で、かつ、分岐口４よりも大径となる拡径状態、換言すれば、穿孔機Ｃのカッター９の通過移動を許容する拡径状態から分岐口４に挿入装着可能な縮径状態に弾性変形可能な防錆ブッシュ５が、拡径状態で組付けられているとともに、前記継手本体６には、拡径状態にある防錆ブッシュ５を縮径状態に操作する縮径操作手段Ｄと、縮径状態にある防錆ブッシュ５を分岐口４の所定装着位置に穿孔軸線Ｙ方向から押し込む押込み手段Ｅとが設けられている。
【００３３】
更に、前記分岐管部２の内壁部２ｂと防錆ブッシュ５との径方向で相対向する部位には、防錆ブッシュ５の先端部が流体輸送管１の外周面から離れた待機位置で、かつ、分岐管部２と同芯又はほぼ同芯状態に仮止め保持する仮止め手段Ｆが設けられている。
【００３４】
前記防錆ブッシュ５は、図９（イ）、（ロ）に示すように、周方向の一箇所が切断された円筒状に構成され、それの両端部には、拡径状態から縮径状態への弾性変形に連れて重合状態に移動案内するカム面５ａが形成されているとともに、防錆ブッシュ５が装着状態にあるとき、両端部のカム面５ａ同士が接当して外周面が分岐口４の内径に相当する真円形状になるように構成されている。
【００３５】
前記縮径操作手段Ｄは、図３、図５、図６に示すように、分岐管部２の周方向複数箇所（当該実施形態では４箇所）の各々に、径方向に貫通する状態で雌ネジ部２ｃが形成され、各雌ネジ部２ｃに、防錆ブッシュ５を縮径状態にまで縮径側に押圧可能な押しボルト１３が螺合されているとともに、各押しボルト１３には、分岐管部２の内壁部２ｂとの接当で押しボルト１３の径方向外方への抜出しを阻止するＣ形状の抜止め輪１４を装着するための第１周溝１３ａと、雌ネジ部１２の内周面との間を摺動可能な状態で密封する第２シール材１５を装着するための第２周溝１３ｂと、押しボルト１３を螺合操作するための回転操作用凹部１３ｃとが形成されている。
【００３６】
また、抜止め輪１４が分岐管部２の内壁部２ｂに接当している状態において、押しボルト１３の頭部側に形成された雄ネジ１３ｄの一部が、雌ネジ部２ｃの先端外側面２ｄよりも外方に突出するように構成し、この雄ネジ１３ｄの突出部分には、分岐口４に対する防錆ブッシュ５の装着作業が終了したとき、雌ネジ部２ｃの先端外側面２ｄとの間を密封する第３シール材１６を備えたキャップ１７が螺合可能に構成されている。
【００３７】
前記押込み手段Ｅは、図４、図５、図６に示すように、分岐管部２の周方向複数箇所（当該実施形態では４箇所）に貫通形成された各取付け孔２ｅに、径方向に沿う操作軸２０が摺動並びに回転自在に挿設され、各操作軸２０の内側端部には、防錆ブッシュ５の後端部を分岐口４側に向って所定装着位置にまで押圧するカム状の押圧部２１が連設されているとともに、分岐管部２には、防錆ブッシュ５の外周面よりも径方向外方に移動させた格納位置で押圧部２１を収納する格納凹部２ｆが外方に膨出形成されていて、各押圧部２１が、分岐管部２内に設けられた防錆ブッシュ５の後端部を分岐口４側に押圧する押圧作用位置と、防錆ブッシュ５の外周面よりも径方向外方に移動させた格納位置とに切換え操作自在に構成されている。
【００３８】
また、各操作軸２０の外側端部には、スパナ等の工具に対する回転操作用軸部２０ａが形成されているとともに、分岐管部２の各取付け孔２ｅに臨む内周面には、操作軸２０の外周面との間を密封するＯリング等の第４シール材２２が設けられ、更に、防錆ブッシュ５を分岐口４の所定装着位置に押込んだ操作位置で各押圧部２１を固定するロック手段Ｇが設けられている。
【００３９】
前記ロック手段Ｇは、図６（ニ）、図８に示すように、分岐管部２の外周面に、操作軸２０の外側軸部に対して横方向から係合可能な係合溝部２３ａを形成してあるロック基板２３がボルト７で脱着自在に締付け固定されているとともに、このロック基板２３には、これの係合溝部２３ａとの間で操作軸２０の外側軸部を挾持固定するための押圧突起部２４ａを備えた挾持部材２４がボルト７で脱着自在に締付け固定されている。
【００４０】
前記仮止め手段Ｆは、図５に示すように、分岐管部２の内壁部２ｂに形成された円環状の係合凹部１８と、該係合凹部１８に係合して分岐管部２と防錆ブッシュ５との穿孔軸線Ｙ方向での相対移動を規制し、かつ、一定以上の操作力が加えられたときに係合凹部１８を通過移動可能な状態で防錆ブッシュ５に形成された円環状の係合凸部１９とから構成されているとともに、前記係合凸部１９が、防錆ブッシュ５を分岐口４の所定装着位置に押込んだとき、流体輸送管１の外周面の分岐口４周縁に穿孔軸線Ｙ方向から接当する当り部に兼用構成されている。
【００４１】
前記穿孔機Ｃとしては、従来から種々の構造のものが存在するが、その一例を挙げると、図１、図２に示すように、電動モータやエンジン等の原動部の駆動により、ケーシング２５に支承された回転並びに穿孔軸線Ｙ方向に摺動自在な駆動回転軸２６に対して駆動回転力と送り力とを付与し、この駆動回転軸２６の先端部の連結フランジ部２６ａに他種のものと付替え自在に連結されたカッター９の一例であるホールソーを、作業用開閉弁Ｂ内の流路と管継手Ａの分岐管部２内の流路とを通して水平又は略水平方向から送り込むことにより、流体輸送管１の管壁に管軸芯Ｘに対して直交する穿孔軸線Ｙ方向に貫通する分岐口４を切削形成する。
【００４２】
前記ホールソー９は、切削チップを先端部に備えた円筒状ボディー９Ａの底壁部の中心位置に、切削チップよりも前方に突出するセンタードリル９Ｂを設けて構成されているとともに、前記ケーシング２５の先端部には、弁ケース１０の他端に一体形成された連結フランジ部１０ｂに対して、締結手段の一例である複数本のボルト７・ナット８を介して脱着自在に固定連結される連結フランジ部２５ａが一体形成されている。
【００４３】
次に、上述の如く構成された管継手Ａを用いての防錆ブッシュ５の取付け方法について説明する。
（イ）図１に示すように、管継手Ａの分岐管部２内に、分岐口４に臨む管壁部の孔内周面１ａに弾性復元力で密着装着可能で、かつ、分岐口４を形成する穿孔機Ｃのホールーソー９の通過移動を許容する拡径状態から分岐口４に挿入装着可能な縮径状態に弾性変形可能な防錆ブッシュ５を、拡径状態で予め組付けるとともに、この防錆ブッシュ５に形成された仮止め手段Ｆの係合凸部１９を、分岐管部２の内壁部２ｂに形成された係合凹部１８に係合させ、防錆ブッシュ５を、それの先端部が流体輸送管１の外周面から離れた待機位置で、かつ、分岐管部２と同芯又はほぼ同芯状態に仮止め保持する。
【００４４】
（ロ）図１に示すように、防錆ブッシュ５を組付けてある管継手Ａの各分割ケース体６Ａ〜６Ｃを、流体輸送管１の分岐口４形成箇所の外周面に、それとの間にシール材３を介装した状態でボルト７・ナット８を介して外装固定したのち、分岐管部２の連結フランジ部２ａに、作業用開閉弁Ｂの一方の連結フランジ部１０ａをボルト７等で固定連結し、更に、作業用開閉弁Ｂの他方の連結フランジ部１０ｂに、穿孔機Ｃの連結フランジ部２５ａをボルト７・ナット８等で固定連結する。
【００４５】
（ハ）図２に示すように、作業用開閉弁Ｂの弁体１１を開き操作するとともに、穿孔機Ｃの原動部を駆動して、駆動回転軸２６に駆動回転力と送り力とを付与し、この駆動回転軸２６の連結フランジ部２６ａに固定連結されたホールソー９を、作業用仕切弁Ｂ内の流路及び分岐管部２内の流路を通して水平又は略水平方向から送り込むことにより、流体輸送管１の管壁に管径方向から分岐口４を切削形成する。
【００４６】
（ニ）流体輸送管１に対する穿孔作業が終了すると、穿孔機Ａの原動部を逆転駆動するか、若しくは、手動ハンドルを操作して、ホールソー９を図１に示す初期の待機位置にまで戻し移動させたのち、作業用仕切弁Ｂの弁体１１を閉じ作動させる。
【００４７】
（ホ）図６（イ）に示すように、縮径操作手段Ｄの各押しボルト１３を押込み側に螺合操作して、ホールーソー９の通過移動を許容する拡径状態にあった防錆ブッシュ５を、それの弾性復元力に抗して分岐口４に挿入装着可能な縮径状態にまで弾性変形させる。
このとき、防錆ブッシュ５の両端部は、図９（イ）に示すように、拡径状態から縮径状態への弾性変形に連れて重合状態になる。
【００４８】
（ヘ）図６（イ）、（ロ）に示すように、押込み手段Ｅの各操作軸２０を径方向内方側に摺動操作して、各操作軸２０の内側端部に連設された押圧部２１を、分岐管部２の格納凹部２ｆ内に収納した格納位置、つまり、防錆ブッシュ５の外周面よりも径方向外方に移動させた格納位置から、防錆ブッシュ５の後端部を分岐口４側に向って押圧可能な押圧作用位置に切替えたのち、各操作軸２０の回転操作用軸部２０ａをスパナ等の工具で押込み側に回転操作し、各押圧部２１で防錆ブッシュ５の後端部を分岐口４側に向って所定装着位置にまで押圧移動させる。
【００４９】
このとき、仮止め手段Ｆの一方の構成部材である防錆ブッシュ５側の係合凸部１９が、分岐管部２の内壁部２ｂに形成された仮止め手段Ｆの他方の構成部材である係合凹部１８から抜け出し、防錆ブッシュ５が所定装着位置に到達した時点で、図６（ロ）及び図７に示すように、流体輸送管１の外周面の分岐口４周縁に穿孔軸線Ｙ方向から接当して、それ以上の防錆ブッシュ５の押込み移動を阻止する。
【００５０】
（ト）図６（ハ）に示すように、防錆ブッシュ５が所定装着位置に押込み操作されると、押込み手段Ｅの各押圧部２１を押込み操作位置又はその近傍に保持したまま、縮径操作手段Ｄの各押しボルト１３を縮径操作力（押込み力）解除側に螺合操作して、所定装着位置にある防錆ブッシュ５を、分岐口４に臨む管壁部の孔内周面１ａに被覆密着するまで、それの弾性復元力で拡径側に弾性変形させる。
【００５１】
このとき、防錆ブッシュ５の両端部のカム面５ａ同士が接当して、該防錆ブッシュ５の外周面が分岐口４の内径に相当する真円形状となるから、分岐口４に臨む管壁部の孔内周面１ａに良好に被覆密着し、管壁部の孔内周面１ａの腐蝕、発錆を効果的に抑制することができる。
【００５２】
（チ）図６（ニ）に示すように、押込み手段Ｅの各押圧部２１を、所定装着位置にある防錆ブッシュ５の後端部に接当させた押込み操作位置に維持したまま、ロック手段Ｇの一方の構成部材である各ロック基板２３の係合溝部２３ａを、操作軸２０の外側軸部に対して横方向から係合させ、その係合状態で各ロック基板２３を分岐管部２の外周面にボルト７で締付け固定したのち、ロック手段Ｇの他方の構成部材である各挾持部材２４を、それの押圧突起部２４ａを操作軸２０の外側軸部に当て付けた状態でロック基板２３にボルト７で締付け固定し、このボルト７の締付け操作に連れて、ロック基板２３の係合溝部２３ａと挾持部材２４の押圧突起部２４ａとの間で操作軸２０の外側軸部を挾持固定する。
【００５３】
それ故に、押込み後に不要となる押圧部２１を、防錆ブッシュ５の抜止め部材に用いることができるから、防錆ブッシュ５を分岐口４の所定装着位置に強固に保持することができるとともに、そのための抜止め構造も、押込み手段Ｅの押圧部２１を利用して簡単かつ製造コスト面で有利に構成することができる。
【００５４】
〔第２実施形態〕
上述の第１実施形態では、管継手Ａに設けた押込み手段Ｅによって、縮径状態にある防錆ブッシュ５を分岐口４の所定装着位置に穿孔軸線Ｙ方向から押し込むように構成したが、図１０（イ）〜（ハ）に示すように、防錆ブッシュ５の後端部に、分岐口４に挿入装着可能な縮径状態にあるとき、穿孔機Ｃのホールソー９の先端部と穿孔軸線Ｙ方向から接当可能で、かつ、ホールソー９の通過移動を許容する拡径状態にあるときには、防錆ブッシュ５の弾性復元力でホールソー９の外周面よりも径方向外方に拡径した非接当姿勢となる受け部５ｂを一体形成して、前記押込み手段Ｅを、穿孔機Ｃのホールソー９をもって兼用するように構成してもよい。
【００５５】
そして、図１０（イ）に示すように、穿孔機Ｃのホールソー９による穿孔後で、かつ、少なくともホールソー９が防錆ブッシュ５から引抜かれた時点以降において、図１０（ロ）に示すように、管継手Ａに設けた縮径操作手段Ｄによって、拡径状態にある防錆ブッシュ５を、それの弾性復元力に抗して分岐口４に挿入装着可能な縮径状態に操作したのち、押込み手段Ｅを兼用構成する穿孔機Ｃのホールソー９を流体輸送管１側に再移動させると、このホールソー９の先端部が、縮径状態にある防錆ブッシュ５の受け部５ｂに穿孔軸線Ｙ方向から接当し、防錆ブッシュ５が分岐口４の所定装着位置にまで押し込まれる。
【００５６】
仮止め手段Ｆの一方の構成部材である防錆ブッシュ５側の係合凸部１９が、分岐管部２の内壁部２ｂに形成された仮止め手段Ｆの他方の構成部材である係合凹部１８から抜け出し、防錆ブッシュ５が所定装着位置に到達した時点で、図１０（ハ）に示すように、流体輸送管１の外周面の分岐口４周縁に穿孔軸線Ｙ方向から接当して、それ以上の防錆ブッシュ５の押込み移動を阻止する。この時点で、穿孔機Ａの原動部を逆転駆動するか、若しくは、手動ハンドルを操作して、ホールソー９を初期の待機位置にまで戻し移動させる。
【００５７】
それ故に、押込み手段Ｅを構成するための特別な構造が不要で、しかも、穿孔機Ｃの送り機構を利用して防錆ブッシュ５を分岐口４の所定装着位置にまで押し込むことができるから、管継手構造の簡素化と施工コストの低廉化のみならず、工期の短縮化と労力の軽減化とを図ることができる。
尚、その他の構成は、第１実施形態で説明した構成と同一であるから、同一の構成箇所には、第１実施形態と同一の番号を付記してそれの説明は省略する。
【００５８】
〔第３実施形態〕
図１１に示す管継手には、縮径状態にある防錆ブッシュ５の分岐口４側への装着移動を許容しながら、分岐口４の所定装着位置に押し込まれた防錆ブッシュ５が、縮径操作手段Ｄによる縮径操作力の解除操作に連れて、分岐口４に臨む管壁部の孔内周面１ａに被覆密着するまで、それの弾性復元力で拡径側に弾性変形されたとき、防錆ブッシュ５の抜け出し移動を接当阻止する抜出し防止手段３０が設けられている。
【００５９】
前記抜出し防止手段３０は、分岐管部２の内壁部２ｂの周方向複数箇所又は全周域で、かつ、分岐口４の所定装着位置に押し込まれた防錆ブッシュ５の後端に対応する部位に、図１１（イ）に示すように、防錆ブッシュ５が縮径状態に操作されているとき、防錆ブッシュ５の最大外径部である後端側の受け部５ｂと接触しない突出代、換言すれば、縮径状態にある防錆ブッシュ５の分岐口４側への装着移動を許容する突出代に形成され、かつ、図１１（ロ）に示すように、防錆ブッシュ５が管壁部の孔内周面１ａに被覆密着する状態にまで拡径変形されたとき、防錆ブッシュ５の後端側の受け部５ｂに対して穿孔軸線Ｙ方向から接当する抜止め突起から構成されている。
【００６０】
尚、その他の構成は、第１実施形態及び第２実施形態で説明した構成と同一であるから、同一の構成箇所には、各実施形態と同一の番号を付記してそれの説明は省略する。
【００６１】
〔第４実施形態〕
図１２に示すように、防錆ブッシュ５の外周面の全域に、分岐口４に臨む管壁部の孔内周面１ａとの間の被覆密封性能を高めるために、ゴムライニング層等の弾性シール層１２を形成して実施してもよい。
尚、前記弾性シール層１２は、防錆ブッシュ５の外周面のうち、少なくとも分岐口４に臨む管壁部の孔内周面１ａと接触する領域に形成してあればよい。
また、その他の構成は、第１実施形態で説明した構成と同一であるから、同一の構成箇所には、第１実施形態と同一の番号を付記してそれの説明は省略する。
【００６２】
〔第５実施形態〕
上述の第４実施形態では、防錆ブッシュ５の外周面の全域に均等又は略均等な厚みで弾性シール層１２を形成したが、図１３に示すように、弾性シール層１２のうち、防錆ブッシュ５が分岐口４の所定装着位置にまで押し込まれとき、流体輸送管１の内周面及び外周面に対応する領域のシール層部分１２ａ，１２ｂを、他の部位のシール層部分よりも厚肉に形成して、流体輸送管１の内周面及び外周面の分岐口４周縁にもそれぞれ密接するようにし、防錆ブッシュ５の抜止め機能を高めると同時に、分岐口４に臨む管壁部の孔内周面１ａと防錆ブッシュ５の外周面との間の被覆密封性能を高めるように構成してもよい。
尚、その他の構成は、第１実施形態で説明した構成と同一であるから、同一の構成箇所には、第１実施形態と同一の番号を付記してそれの説明は省略する。
【００６３】
〔その他の実施形態〕
（１）上述の第１実施形態では、ホールソー９を初期の待機位置にまで戻し移動させるとともに、作業用仕切弁Ｂの弁体１１を閉じ作動させたのち、防錆ブッシュ５を縮径操作手段Ｄで縮径操作したが、ホールソー９が防錆ブッシュ５を抜出した時点で、防錆ブッシュ５を縮径操作手段Ｄで縮径操作してもよい。
【００６４】
（２）上述の第１実施形態では、前記縮径操作手段Ｄを複数の押しボルト１３から構成したが、この構成に限定されるものではなく、拡径状態にある防錆ブッシュ５を縮径状態に操作することのできるものであれば、如何なる構造のものを採用してもよい。
【００６５】
（３）上述の第１実施形態では、前記押込み手段Ｅを、操作軸２０とカム状の押圧部２１とから構成したが、この構成に限定されるものではなく、縮径状態にある防錆ブッシュ５を分岐口４の所定装着位置に穿孔軸線Ｙ方向から押し込むことのできるものであれば、如何なる構造のものを採用してもよい。
【００６６】
（４）上述の第１実施形態では、前記仮止め手段Ｆを、分岐管部２の内壁部２ｂに形成された円環状の係合凹部１８と防錆ブッシュ５に形成された円環状の係合凸部１９とから構成したが、この構成に限定されるものではなく、防錆ブッシュ５をそれの先端部が流体輸送管１の外周面から離れた待機位置で、かつ、分岐管部２と同芯又はほぼ同芯状態に仮止め保持することのできるものであれば、如何なる構造のものを採用してもよい。
【００６７】
（５）前記防錆ブッシュ５を、周方向の一箇所が切断された金属製の円筒状のブッシュ本体と、該ブッシュ本体の両端部間を密封する状態で連設される伸縮自在な弾性膜体とから構成するとともに、防錆ブッシュ５が装着状態にあるとき、ブッシュ本体の外面と弾性膜体の外面とが分岐口４の内径に相当する真円形状又は略真円形状になるように構成してもよい。
【図面の簡単な説明】
【図１】本願発明の第１実施形態を示す穿孔作業前の全体の一部断面側面図
【図２】穿孔作業時の全体の一部断面側面図
【図３】図１におけるＩＩＩ−ＩＩＩ線拡大断面図
【図４】図１におけるＩＶ−ＩＶ線拡大断面図
【図５】穿孔作業後の要部の拡大断面側面図
【図６】（イ）〜（ニ）は防錆ブッシュの装着工程を示す要部の断面側面図
【図７】防錆ブッシュが所定装着位置に押込まれたときの要部の断面側面図
【図８】ロック手段で押込み手段の操作軸を固定したときの要部の拡大平面図
【図９】防錆ブッシュと縮径操作手段との関係を示し、
（イ）は防錆ブッシュが縮径状態にあるときの要部の断面正面図
（ロ）は防錆ブッシュが装着状態にあるときの要部の断面正面図
【図１０】本願発明の第２実施形態を示し、（イ）〜（ハ）は防錆ブッシュの装着工程を示す要部の断面側面図
【図１１】本願発明の第３実施形態を示し、（イ）、（ロ）は防錆ブッシュの装着工程を示す要部の断面側面図
【図１２】本願発明の第４実施形態を示す要部の拡大断面側面図
【図１３】本願発明の第５実施形態を示す要部の拡大断面側面図
【図１４】従来の管分岐口への防錆ブッシュの取付け方法を示す要部の断面側面図
【符号の説明】
Ａ管継手
Ｃ穿孔機
Ｄ縮径操作手段
Ｅ押込み手段
Ｆ仮止め手段
Ｇロック手段
Ｙ穿孔軸線
１流体輸送管
１ａ孔内周面
２分岐管部
３シール材
４分岐口
５防錆ブッシュ
５ａカム面
５ｂ受け部
６継手本体
９カッター（ホールソー）
１８係合凹部
１９係合凸部
２１押圧部[0001]
BACKGROUND OF THE INVENTION
The present invention externally fixes a pipe joint provided with a branch pipe part on the outer peripheral surface of a fluid transport pipe such as a water pipe with a sealing material interposed therebetween, and is attached to the branch pipe part side of the pipe joint. With the cutter of the drilling machine installed, the branch port is formed through the tube wall sealed with the sealing material through the branch tube, and then the rust-proof bush is in close contact with the inner peripheral surface of the tube wall facing the branch port The attachment method of the antirust bushing to the pipe branching port to be attached in step 1 and the improvement of the pipe joint used therefor.
[0002]
[Prior art]
In general, the branch port that is formed through the fluid transport pipe is more susceptible to corrosion and rusting than other parts that are lined for corrosion and rust prevention. A method of attaching an excellent anti-rust bushing to the branch port is adopted.
And in the conventional attachment method of a rust prevention bush, as shown in FIG. 14, the pipe joint provided with the branch pipe part 2 which can be connected to the branch port 4 penetrated and formed in the fluid transport pipe 1 at this pipe wall part. A is externally fixed with the sealing material 3 interposed between the outer peripheral surface of the fluid transport pipe 1 and the working on-off valve B and the punching machine ( (Not shown) are sequentially fixedly connected, and the sealing material is maintained while maintaining the flow of the fluid in the fluid transport pipe 1 through the working on-off valve B and the branch pipe 2 of the pipe joint A which are opened by the cutter of the punching machine. After the branch port 4 is formed through the tube wall portion sealed in 3, the punching machine is removed from the work opening / closing valve B that has been closed.
[0003]
Next, a cylindrical elastic body 50 in which a cylindrical rust-proof bushing 5 having an outer diameter that can be fitted into the branch port 4 of the fluid transport pipe 1 is attached to the working on-off valve B in a jacket state, The elastic body 50 is inserted between the insertion shaft 51 that inserts and supports the elastic body 50 and the first pinching body 51A that is slidably fitted to the insertion shaft 51 and formed at the distal end portion of the insertion shaft 51. A bush insertion machine H provided with a pressing cylinder shaft 52 forming a second pinching body 52A for compressing the screw is attached, and the rust prevention bush 5 attached to the elastic body 50 of the bush insertion machine H is opened. After inserting into the predetermined mounting position of the branch port 4 of the fluid transport pipe 1 through the operated on-off valve B and the branch pipe portion 2 of the pipe joint A, the first clamping body 51A of the insertion shaft 51 and the pressing The elastic body 50 is compressed between the second pinching body 52A of the cylindrical shaft 52 and bulged radially outward. Accordingly, the rust bush 5 has been mounted by deforming until it engages the retaining state to the opening peripheral edge of the branch port 4 (for example, JP-B-57-12916, JP-see JP-B-61-42158).
[0004]
[Problems to be solved by the invention]
In the conventional method, when the anticorrosion bush 5 is attached to the branch port 4 drilled by the drilling machine, the process of attaching the bush insertion machine H to the work on-off valve B, the process of opening the work on-off valve B, the bush insertion Inserting the rust preventive bush 5 attached to the elastic body 50 of the machine H into the branch port 4 of the fluid transport pipe 1 through the work on-off valve B that has been opened and the branch pipe portion 2 of the pipe joint A; The step of deforming the anticorrosion bush 5 inserted at the predetermined mounting position until it is prevented from being engaged with the opening periphery of the branch port 4, the step of returning the elastic body 50 to the standby position, and the step of closing the work on-off valve B The process of removing the bush insertion machine H from the work on-off valve B is necessary, and the bush mounting work requires a great deal of labor and labor. In addition, it is necessary to prepare a large bush insertion machine H for construction. Remove the drilling machine Only after, it is not possible to attach the bushing insertion machine H, easily lead to soaring of prolonged and construction cost of the construction period.
[0005]
The present invention has been made in view of the above-described situation, and the main problem is that the mounting work of the rust prevention bush can be performed at any time after the completion of the drilling work. Provided is a method for attaching a rust-proof bushing to a pipe branch port and a pipe joint used therefor, which can reduce the number of work steps and labor required for mounting work, shorten the construction period and reduce the construction cost. In the point.
[0006]
[Means for Solving the Problems]
According to the first aspect of the present invention, a pipe joint provided with a branch pipe portion is externally fixed to an outer peripheral surface of a fluid transport pipe with a sealing material interposed therebetween, and the branch pipe of the pipe joint is provided. After a branch port is formed in the tube wall part that is sealed with a sealing material through the branch pipe part with a cutter of a drilling machine installed on the side of the pipe, a rust-proof bushing is formed on the inner peripheral surface of the pipe wall part facing this branch port Is a method of attaching a rust-proof bushing to a pipe branch port to which the
In the branch pipe part of the pipe joint, it can be attached tightly to the inner peripheral surface of the hole of the pipe wall part with elastic restoring force, and from the expanded diameter state allowing the passage of the cutter of the drilling machine forming the branch port to the branch port A rust preventive bush that can be elastically deformed into a reduced diameter state that can be inserted and mounted is pre-assembled in an expanded state, and after being drilled by a cutter of a drilling machine, it is in an expanded state by a reduced diameter operating means provided in a pipe joint. After operating the rust-proof bushing to the reduced diameter state, push the rust-proof bushing in the reduced-diameter state into the specified mounting position of the branch port with the pushing means, and release the diameter-reducing operation force by the diameter-reducing operation means. It is in the point comprised so that it may closely_contact | adhere to the hole inner peripheral surface of a pipe wall part with the elastic restoring force.
[0007]
According to the above characteristic configuration, before drilling with a cutter of a drilling machine, a rust-proof bushing is assembled in advance in a diameter-enlarged state allowing the passage of the cutter into the branch pipe portion of the pipe joint, and the pipe joint is fluid transported. Tube wall sealed with sealing material through a rust preventive bush in the branch pipe by a cutter of a drilling machine attached to the branch pipe side of the pipe joint after exterior fixing with a sealant interposed on the outer peripheral surface of the pipe A branch port is formed through the part.
[0008]
Then, after piercing by the cutter of the punching machine, and at least after the time when the cutter is pulled out from the rust preventive bush, the rust preventive bush in the expanded state is reduced by the diameter reducing operation means provided in the pipe joint. After operating in a reduced diameter state that can be inserted and installed in the branch port against the elastic restoring force, the rust preventive bush in this reduced diameter state is pushed into the predetermined installation position of the branch port by the pushing means, and the diameter is reduced in that state. When the diameter reduction force by the means is released, the rust preventive bush is elastically deformed to the enlarged diameter side by elastic restoring force, and the outer peripheral surface of the rust preventive bush is elastically restored to the inner peripheral surface of the tube wall portion facing the branch port. By covering and adhering, corrosion and rusting of the inner peripheral surface of the hole in the tube wall can be suppressed.
[0009]
Therefore, the number of work steps and labor can be greatly reduced as compared with the conventional method, and it is not necessary to prepare a large bush insertion machine. After drilling with a cutter, and at least after the cutter is pulled out from the rust-proof bush, it can be performed at any time, so there are fewer restrictions on the work process plan, shortening the construction period and reducing the construction cost. Can be achieved.
[0010]
According to a second aspect of the present invention, there is provided a characteristic configuration of a method for attaching a rust preventive bush to a pipe branch port, wherein the rust preventive bush is in contact with a rear end portion of the rust preventive bush from a drilling cutter in a reduced diameter state. And the pushing means is configured to be combined with a cutter of a punching machine.
[0011]
According to the above-described characteristic configuration, the rust preventive is in an expanded state by the diameter reducing operation means provided in the pipe joint after the punching by the cutter of the punching machine and at least after the cutter is pulled out from the rust preventive bush. After operating the bush in a diameter-reduced state that can be inserted and mounted in the branch port against its elastic restoring force, the cutter of the drilling machine that also serves as the pushing means is moved again to the fluid transport pipe side. The tip of the butt comes into contact with the receiving portion of the rust preventive bush in the reduced diameter state from the direction of the drilling axis, and the rust preventive bush is pushed into the predetermined mounting position of the branch port.
[0012]
Therefore, there is no need for a special structure for constructing the pushing means, and the rust preventive bush can be pushed into the predetermined mounting position of the branch port by using the feed mechanism of the drilling machine, thereby simplifying the pipe joint structure. In addition to lowering construction costs, the construction period can be shortened and labor can be reduced.
[0013]
According to a third aspect of the present invention, there is provided a pipe wall portion sealed with a sealing material on a joint body which is externally fixed in a state where a sealing material is interposed between the fluid transport pipe and an outer peripheral surface thereof. A pipe joint in which a branch pipe portion that can communicate with a branch port that is formed through the pipe is formed,
In the branch pipe portion, a shrinkage that can be attached tightly to the inner peripheral surface of the hole of the pipe wall portion facing the branch port with an elastic restoring force and that can be inserted into the branch port from a diameter-expanded state larger than the branch port. A rust preventive bush that is elastically deformable in a diameter state is assembled in a diameter expanded state, and the joint body has a diameter reducing operation means for operating the rust preventive bush in a diameter expanded state to a diameter reduced state, Pushing means for pushing the rust-proof bushing in the reduced diameter state into the predetermined mounting position of the branch port from the direction of the drilling axis is provided.
[0014]
According to the above characteristic configuration, the anticorrosion bush is assembled in advance in a diameter expanded state that is larger than the branch port formed in the fluid transport pipe in the branch pipe portion of the joint main body, and the joint main body is attached to the fluid transport pipe. After fixing the exterior with a sealing material on the outer peripheral surface of the pipe, the tube wall part sealed with the sealing material through the rust prevention bush in the branch pipe part by the cutter of the drilling machine attached to the branch pipe part side of the joint body A branch port is formed in the through hole.
[0015]
Then, after piercing by the cutter of the punching machine, and at least after the time when the cutter is pulled out from the rust preventive bush, the rust preventive bush in the expanded state is reduced by the diameter reducing operation means provided in the joint body. After operating in a reduced diameter state that can be inserted and installed in the branch port against the elastic restoring force, the rust preventive bush in this reduced diameter state is pushed into the predetermined installation position of the branch port by the pushing means provided in the joint body, In this state, when the diameter reducing operation force by the diameter reducing operation means is released, the rust preventive bush is elastically deformed to the enlarged diameter side by the elastic restoring force, and the inner periphery of the tube wall portion where the outer peripheral surface of the rust preventive bush faces the branch port Corrosion and rusting of the inner peripheral surface of the hole in the tube wall can be suppressed by covering and adhering to the surface with elastic restoring force.
[0016]
Therefore, the number of work steps and labor can be greatly reduced as compared with the conventional method, and it is not necessary to prepare a large bush insertion machine. After drilling with a cutter and at least after the cutter is pulled out from the rust prevention bush, it can be performed at any time, so there are few restrictions on the work process plan, and the mounting work and drilling of the rust prevention bush It is also possible to perform the machine removal work in parallel, thereby shortening the construction period and reducing the construction cost.
[0017]
The characteristic structure of the pipe joint according to claim 4 of the present invention is that the tip portion of the rust prevention bush is separated from the outer peripheral surface of the fluid transport pipe at a portion where the inner wall portion of the branch pipe portion and the rust prevention bush face each other in the radial direction. There is provided a temporary fixing means for temporarily fixing and holding at the standby position and concentrically or substantially concentrically with the branch pipe portion.
[0018]
According to the above characteristic configuration, the antirust bushing assembled in advance in the branch pipe portion from the standby position by the vibration at the time of fixing the joint body to the fluid transport pipe or mounting the drilling machine from the standby position. It is possible to improve the efficiency and reliability of drilling work and bush mounting work by suppressing the movement of the anticorrosion bush in the radial direction and the axial movement of the anticorrosion bush with respect to the axis of the branch pipe. .
[0019]
The characteristic structure of the pipe joint according to claim 5 of the present invention is that the pressing means is provided with a pressing portion that presses the rear end portion of the rust-proof bush provided in the branch pipe portion toward the branch port side, and is rust-proof. The lock means is provided to fix the pressing portion at the operation position where the bush is pushed into the predetermined mounting position of the branch port.
[0020]
According to the above characteristic configuration, the rear end portion of the rust-proof bushing in the reduced diameter state is pushed into the predetermined mounting position of the branch port by the pushing portion of the pushing means provided on the joint body, and in that state, the reduction by the diameter reducing operation means is performed. After releasing the radial operating force, the outer peripheral surface of the rust prevention bush is covered and adhered to the inner peripheral surface of the hole of the tube wall portion facing the branch port with an elastic restoring force, and then the pressing portion at the pressing operation position is locked by the locking means. By fixing, the pressing part which becomes unnecessary after pushing in can be used as a retaining member for the rust prevention bush.
[0021]
Therefore, the rust-proof bush can be firmly held at the predetermined mounting position of the branch port, and the retaining structure for the rust-proof bush can be configured simply and advantageously in terms of manufacturing cost by using the pressing portion of the pressing means. it can.
[0022]
The characteristic structure of the pipe joint according to claim 6 of the present invention is that the pushing means has a pressing action position for pressing the rear end portion of the rust prevention bush provided in the branch pipe portion toward the branch port side, and the outer periphery of the rust prevention bush. A pressing portion that can be switched to a storage position moved radially outward from the surface is provided.
[0023]
According to the above characteristic configuration, when the rust preventive bush in the reduced diameter state is pushed into the predetermined mounting position of the branch port by the pushing means provided in the joint body, the rust preventing bush was in the retracted position that does not interfere with the drilling work by the drilling machine. Since the pressing portion of the pressing means is simply moved to the radially inward pressing position and the pressing operation is performed at that position, the mounting work of the rust preventive bush can be performed efficiently and easily.
[0024]
The characteristic structure of the pipe joint according to claim 7 of the present invention is that the temporary fixing means engages with the engaging recess formed in the inner wall portion of the branch pipe portion, and the branch pipe portion and the rust prevention portion. From the engagement convex part formed on the rust preventive bush in a state in which the relative movement in the drilling axis direction with respect to the bush is restricted, and the movable part can pass through the engagement concave part when a certain operating force is applied. It is in the point which is comprised.
[0025]
According to the above characteristic configuration, since the engagement concave portion and the engagement convex portion are only formed in the radially opposing portions of the inner wall portion of the branch pipe portion and the rust prevention bush, the rust prevention bush is placed in the standby position. Thus, the temporary fixing means for temporarily fixing and concentrically concentrically or substantially concentrically can be advantageously configured in terms of structure and manufacturing cost.
[0026]
The feature of the pipe joint according to claim 8 of the present invention is that the engaging convex portion of the temporary fixing means is perforated around the periphery of the branch port of the fluid transport pipe when the rust preventive bush is pushed into a predetermined mounting position of the branch port. It exists in the point comprised by the contact part which contacts from an axial direction.
[0027]
According to the above characteristic configuration, when the rust preventive bush is pushed into the predetermined mounting position of the branch port using the engagement convex portion on the rust preventive bush side constituting the temporary fixing means, the periphery of the branch port of the fluid transport pipe Because it is configured with a contact part that prevents further push-in by contacting it, there is no need to separately provide a special stopper that regulates the push-in amount of the anti-rust bushing, simplifying the structure and reducing manufacturing costs And can be promoted.
[0028]
The characteristic structure of the pipe joint according to claim 9 of the present invention is that the rust-proof bushing is formed in a cylindrical shape in which one place in the circumferential direction is cut, and at both ends thereof, the diameter-expanded state is reduced to the diameter-reduced state. A cam surface that moves and guides to the superposition state along with the elastic deformation of the rust prevention bush is formed, and when the rust preventive bush is in a mounted state, the cam surfaces of the both end portions are in contact with each other and the outer peripheral surface is a branch port. It is in the point comprised so that it may become a perfect circle shape corresponded to an internal diameter, or a substantially perfect circle shape.
According to the above characteristic configuration, the cam surfaces formed at both ends of the rust preventive bushes allow the rust preventive bushes to be attached to the branch ports while smoothly performing elastic deformation from the enlarged diameter state to the reduced diameter state. In this state, the cam surfaces come into contact with each other, and the outer peripheral surface thereof becomes a perfect circle shape or a substantially perfect circle shape corresponding to the inner diameter of the branch port, so that the tube wall portion where the outer peripheral surface of the rust prevention bush faces the branch port It is possible to effectively suppress the corrosion and rusting of the hole inner peripheral surface of the tube wall portion by satisfactorily covering and contacting the inner peripheral surface of the hole with an elastic restoring force.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
1-9 cross | intersect with respect to the pipe axis X of the fluid transport pipe 1 on the outer peripheral surface of the existing fluid transport pipe 1, such as a water pipe comprised of a cast iron pipe, a steel pipe, etc. ) Between the outer peripheral surface of the fluid transport pipe 1 and the pipe joint A made of cast iron formed integrally with the branch pipe portion 2 projecting outward along the horizontal or substantially horizontal direction (perforation axis Y direction). Sealed with a sealing material 3 (sealed in a liquid-tight or air-tight state) and fixed by exterior, and opened by a cutter 9 of a punching machine C attached to a branch pipe portion 2 of this pipe joint A via a work on-off valve B The branch port 4 is formed through the tube wall portion sealed with the sealing material (elastic packing) 3 while maintaining the flow of the fluid in the fluid transport pipe 1 through the operated on-off valve B and the branch pipe portion 2. After that, the stainless steel having excellent corrosion resistance and rust resistance is formed on the inner peripheral surface 1a of the pipe wall portion facing the branch port 4. Showing a mounting method of mounting an anti-rust bush 5 made of steel in close contact.
[0030]
As shown in FIGS. 1 to 5, the joint body 6 of the pipe joint A used for the method of attaching the rust prevention bush 5 to the pipe branch port is externally attached to the fluid transport pipe 1 from the outside in the pipe radial direction. It is composed of partially cylindrical divided case bodies 6A to 6C that are divided into a plurality of parts in the free pipe circumferential direction (in this embodiment, divided into three parts). The connecting flange portions 6a to 6c for detachably fixing and connecting the adjacent divided case bodies 6A to 6C, which are sheathed on the fluid transport pipe 1, with a plurality of bolts 7 and nuts 8 as an example of fastening means are integrally formed. In addition, the seal holding groove 6d formed on the inner peripheral surface of each of the divided case bodies 6A to 6C is made of synthetic rubber (for example, styrene butadiene rubber or the like) that seals between the outer peripheral surface of the fluid transport pipe 1 ) Of the sealing material 3 is attached.
[0031]
In addition, the branch pipe portion 2 is integrally formed at the center portion in the tube axis X direction of one split case body 6A and at the center portion in the pipe circumferential direction. The connecting flange portion 2a integrally formed at the tip of the connecting flange portion 10a is integrally formed at one end of the valve case 10 of the working on-off valve B with a plurality of bolts 7 as an example of fastening means. Removably fixedly connected.
[0032]
In the branch pipe portion 2 of the pipe joint A, the diameter of the pipe joint A can be tightly attached to the inner peripheral surface 1a of the pipe wall portion facing the branch port 4 by an elastic restoring force, and the diameter is larger than that of the branch port 4. The state, in other words, the rust preventive bushing 5 that can be elastically deformed from the expanded diameter state that allows passage of the cutter 9 of the drilling machine C to the reduced diameter state that can be inserted into the branch port 4 is assembled in the expanded diameter state. In addition, the joint body 6 is provided with a diameter-reducing operation means D for operating the rust-proof bushing 5 in a diameter-expanded state to a diameter-reduced state and a rust-proof bushing 5 in a diameter-reduced state at a predetermined branch port 4. Pushing means E that pushes into the mounting position from the direction of the drilling axis Y is provided.
[0033]
Furthermore, in the part which the inner wall part 2b of the said branch pipe part 2 and the rust prevention bush 5 mutually oppose in the radial direction, the front-end | tip part of the rust prevention bush 5 is a standby position away from the outer peripheral surface of the fluid transport pipe 1, In addition, a temporary fixing means F is provided for temporarily fixing and holding the branch pipe portion 2 in a concentric or substantially concentric state.
[0034]
As shown in FIGS. 9 (a) and 9 (b), the rust-proof bushing 5 is formed in a cylindrical shape in which one place in the circumferential direction is cut, and at both ends thereof, the diameter-reduced state is reduced to the diameter-reduced state. The cam surface 5a for moving and guiding in the superposition state is formed along with the elastic deformation of the lip, and when the rust prevention bush 5 is in the mounted state, the cam surfaces 5a at both ends abut each other and the outer peripheral surface branches. It is configured to have a perfect circular shape corresponding to the inner diameter of the mouth 4.
[0035]
As shown in FIGS. 3, 5, and 6, the diameter reducing operation means D is a female in a state of penetrating in a radial direction at each of a plurality of circumferential locations (four locations in the embodiment) of the branch pipe portion 2. A screw portion 2c is formed, and each female screw portion 2c is screwed with a push bolt 13 that can press the anticorrosion bush 5 to the reduced diameter side to a reduced diameter state. A first circumferential groove 13a for mounting a C-shaped retaining ring 14 for preventing the push bolt 13 from being pulled out radially outward by contact with the inner wall portion 2b of the tube portion 2, and a female screw portion 12 A second circumferential groove 13b for mounting the second sealant 15 that seals the inner peripheral surface in a slidable state and a concave portion 13c for rotational operation for screwing the push bolt 13 are formed. Has been.
[0036]
Further, in a state where the retaining ring 14 is in contact with the inner wall 2b of the branch pipe portion 2, a part of the male screw 13d formed on the head side of the push bolt 13 is outside the tip of the female screw portion 2c. The protruding portion of the male screw 13d is configured to protrude outward from the side surface 2d, and when the mounting work of the rust prevention bush 5 to the branch port 4 is completed, the outer end surface 2d of the female screw portion 2c A cap 17 having a third sealing material 16 that seals between the two is configured to be screwable.
[0037]
As shown in FIGS. 4, 5, and 6, the pushing means E is provided in the mounting holes 2 e that are formed through a plurality of locations in the circumferential direction of the branch pipe portion 2 (four locations in the embodiment) in the radial direction. The operation shaft 20 is slidably and rotatably inserted, and a cam that presses the rear end portion of the anticorrosion bush 5 toward the branch port 4 to a predetermined mounting position at the inner end portion of each operation shaft 20. In addition to the continuous pressing portion 21, the branch pipe portion 2 has a storage recess 2 f that stores the pressing portion 21 at a storage position that is moved radially outward from the outer peripheral surface of the rust prevention bush 5. A pressing action position where each pressing portion 21 presses the rear end portion of the rust prevention bush 5 provided in the branch pipe portion 2 toward the branch port 4, and the rust prevention bush 5. It is configured to be switchable to a storage position moved radially outward from the outer peripheral surface of the.
[0038]
In addition, a rotation operation shaft portion 20a for a tool such as a spanner is formed at an outer end portion of each operation shaft 20, and an operation shaft is provided on an inner peripheral surface facing each mounting hole 2e of the branch pipe portion 2. A fourth sealing member 22 such as an O-ring is provided to seal between the outer peripheral surface of 20 and each pressing portion 21 is fixed at an operation position in which the rust prevention bush 5 is pushed into a predetermined mounting position of the branch port 4. Locking means G is provided.
[0039]
As shown in FIGS. 6D and 8, the locking means G has an engaging groove 23 a that can be engaged with the outer shaft of the operating shaft 20 from the lateral direction on the outer peripheral surface of the branch pipe portion 2. The formed lock substrate 23 is detachably fastened and fixed with bolts 7, and the outer shaft portion of the operation shaft 20 is clamped and fixed between the lock substrate 23 and the engagement groove portion 23 a. The holding member 24 having the pressing protrusion 24a is fastened and fixed by a bolt 7 so as to be detachable.
[0040]
As shown in FIG. 5, the temporary fixing means F includes an annular engagement recess 18 formed in the inner wall 2 b of the branch pipe portion 2, and the branch pipe portion 2 by engaging with the engagement recess 18. It is formed in the rust prevention bush 5 in a state in which the relative movement with respect to the rust prevention bush 5 in the drilling axis Y direction is restricted and the engagement recess 18 is movable when an operation force of a certain level or more is applied. It is comprised from the annular engagement convex part 19, and when the said engagement convex part 19 pushes the antirust bush 5 in the predetermined mounting position of the branch port 4, it is the outer peripheral surface of the fluid transport pipe 1. It is also used as a contact portion that contacts the periphery of the branch port 4 from the direction of the drilling axis Y.
[0041]
Conventionally, there are various types of drilling machines C, and as an example, as shown in FIGS. 1 and 2, the casing 25 is driven by a driving part such as an electric motor or an engine. A driving rotational force and a feeding force are applied to the driven rotating shaft 26 that is slidable in the direction of drilling axis Y in the supported rotation, and other types of connecting flange portions 26a at the tip of the driving rotating shaft 26 are provided. A hole saw, which is an example of the cutter 9 that is connected in a freely replaceable manner, is fed from the horizontal or substantially horizontal direction through the flow path in the working on-off valve B and the flow path in the branch pipe portion 2 of the pipe joint A. The branch port 4 penetrating in the direction of the drilling axis Y perpendicular to the tube axis X is cut and formed in the tube wall of the fluid transport tube 1.
[0042]
The hole saw 9 is configured by providing a center drill 9B protruding forward from the cutting tip at the center position of the bottom wall portion of the cylindrical body 9A having a cutting tip at the tip thereof. A connecting flange that is detachably fixedly connected to a distal end portion via a plurality of bolts 7 and nuts 8 as an example of a fastening means with respect to a connecting flange portion 10b formed integrally with the other end of the valve case 10. The part 25a is integrally formed.
[0043]
Next, the attachment method of the antirust bushing 5 using the pipe joint A comprised as mentioned above is demonstrated.
(A) As shown in FIG. 1, in the branch pipe portion 2 of the pipe joint A, it can be closely attached to the inner peripheral surface 1a of the pipe wall portion facing the branch port 4 by elastic restoring force, and the branch port 4 The rust preventive bushing 5 that is elastically deformable from a diameter-enlarged state allowing passage movement of the hole saw 9 of the drilling machine C to be formed into a reduced diameter state that can be inserted and attached to the branch port 4 is assembled in advance in the diameter-enlarged state, The engagement protrusion 19 of the temporary fixing means F formed on the rust prevention bush 5 is engaged with the engagement recess 18 formed on the inner wall 2b of the branch pipe portion 2, and the rust prevention bush 5 is The distal end portion is temporarily held in a standby position away from the outer peripheral surface of the fluid transport pipe 1 and concentric with or substantially concentric with the branch pipe portion 2.
[0044]
(B) As shown in FIG. 1, the split case bodies 6A to 6C of the pipe joint A to which the rust preventive bush 5 is assembled are disposed on the outer peripheral surface of the fluid transport pipe 1 where the branch port 4 is formed. After fixing the exterior with bolts 7 and nuts 8 with the sealing material 3 interposed therebetween, one connection flange portion 10a of the work on-off valve B is connected to the connection flange portion 2a of the branch pipe portion 2 with the bolt 7 or the like. Then, the connecting flange portion 25a of the drilling machine C is fixedly connected to the other connecting flange portion 10b of the work on-off valve B with bolts 7 and nuts 8 or the like.
[0045]
(C) As shown in FIG. 2, the valve body 11 of the working on-off valve B is opened and the driving part of the drilling machine C is driven to give the driving rotating shaft 26 driving torque and feeding force. The hole saw 9 fixedly connected to the connecting flange portion 26a of the drive rotating shaft 26 is sent from the horizontal or substantially horizontal direction through the flow passage in the working gate valve B and the flow passage in the branch pipe portion 2, A branch port 4 is cut and formed in the pipe wall of the fluid transport pipe 1 from the pipe radial direction.
[0046]
(D) When the drilling operation for the fluid transport pipe 1 is completed, the driving section of the drilling machine A is driven in reverse or the manual handle is operated to move the hole saw 9 back to the initial standby position shown in FIG. Then, the valve body 11 of the work gate valve B is closed and operated.
[0047]
(E) As shown in FIG. 6 (a), each push bolt 13 of the diameter-reducing operation means D is screwed to the push-in side, and the rust-proof bushing is in a diameter-expanded state allowing passage movement of the hole saw 9. 5 is elastically deformed to a reduced diameter state that can be inserted into and attached to the branch port 4 against its elastic restoring force.
At this time, as shown in FIG. 9A, both end portions of the rust prevention bush 5 are in a polymerized state with elastic deformation from the expanded diameter state to the reduced diameter state.
[0048]
(F) As shown in FIGS. 6 (a) and 6 (b), the operation shafts 20 of the push-in means E are slid inward in the radial direction so as to be connected to the inner ends of the operation shafts 20. From the storage position in which the pressing portion 21 is stored in the storage recess 2f of the branch pipe portion 2, that is, the storage position in which the pressing portion 21 is moved radially outward from the outer peripheral surface of the rust prevention bush 5, After the end portion is switched to the pressing action position that can be pressed toward the branch port 4 side, the rotation operation shaft portion 20a of each operation shaft 20 is rotated to the pressing side with a tool such as a spanner, and each pressing portion 21 is operated. The rear end portion of the rust prevention bush 5 is pressed and moved to the predetermined mounting position toward the branch port 4 side.
[0049]
At this time, the engagement convex portion 19 on the rust preventive bush 5 side, which is one constituent member of the temporary fixing means F, is the other constituent member of the temporary fixing means F formed on the inner wall portion 2b of the branch pipe portion 2. When the anti-corrosion bushing 5 comes out of the engagement recess 18 and reaches the predetermined mounting position, as shown in FIGS. 6 (b) and 7, a perforation axis Y is formed on the periphery of the branch port 4 on the outer peripheral surface of the fluid transport pipe 1. Touching from the direction prevents the rust preventive bushing 5 from being pushed further.
[0050]
(G) As shown in FIG. 6 (c), when the rust preventive bush 5 is pushed into a predetermined mounting position, the diameter of the rust prevention bush E is reduced while the pressing portions 21 of the pushing means E are held at or near the pushing operation position. Each push bolt 13 of the operating means D is screwed to the reduced diameter operating force (pushing force) release side so that the rust preventive bushing 5 at the predetermined mounting position faces the inner peripheral surface of the tube wall portion facing the branch port 4. It is elastically deformed to the expanded diameter side by its elastic restoring force until it is in close contact with la.
[0051]
At this time, the cam surfaces 5 a at both ends of the rust prevention bush 5 come into contact with each other, and the outer peripheral surface of the rust prevention bush 5 has a perfect circle shape corresponding to the inner diameter of the branch port 4. It is possible to satisfactorily cover and adhere to the hole inner peripheral surface 1a of the tube wall portion, and to effectively suppress corrosion and rusting of the hole inner peripheral surface 1a of the tube wall portion.
[0052]
(H) As shown in FIG. 6 (d), each pressing portion 21 of the pressing means E is locked while being maintained at the pressing operation position in contact with the rear end portion of the rust preventive bush 5 at the predetermined mounting position. The engaging groove 23a of each lock substrate 23 which is one constituent member of the means G is engaged with the outer shaft portion of the operation shaft 20 from the lateral direction, and each lock substrate 23 is connected to the branch pipe portion in the engaged state. 2 is tightened and fixed to the outer peripheral surface with bolts 7, and then each holding member 24, which is the other constituent member of the locking means G, is locked in a state where its pressing projection 24 a is applied to the outer shaft portion of the operation shaft 20. The base plate 23 is fastened and fixed with the bolt 7, and the outer shaft portion of the operation shaft 20 is held between the engagement groove portion 23 a of the lock substrate 23 and the pressing projection portion 24 a of the holding member 24 as the bolt 7 is tightened. Fix it.
[0053]
Therefore, the pressing portion 21 that is not required after being pushed in can be used as a retaining member for the rust-proof bushing 5. Therefore, the rust-proof bushing 5 can be firmly held at the predetermined mounting position of the branch port 4, and The retaining structure for that purpose can also be configured simply and advantageously in terms of manufacturing cost using the pressing portion 21 of the pressing means E.
[0054]
[Second Embodiment]
In the first embodiment described above, the pushing means E provided in the pipe joint A is configured to push the rust preventive bush 5 in a reduced diameter state into the predetermined mounting position of the branch port 4 from the drilling axis Y direction. As shown in 10 (a) to (c), when the diameter of the rust prevention bush 5 is reduced in diameter so that it can be inserted into the branch port 4, the tip of the hole saw 9 of the drilling machine C and the drilling axis When the diameter of the hole saw 9 can be touched and the hole saw 9 is allowed to pass through, the non-rusted bush 5 has an elastic restoring force and the outer diameter of the hole saw 9 is increased radially outward. The receiving portion 5b having a contact posture may be integrally formed so that the pushing means E is also used as the hole saw 9 of the punching machine C.
[0055]
As shown in FIG. 10 (a), as shown in FIG. 10 (b) after drilling by the hole saw 9 of the drilling machine C and at least after the hole saw 9 is pulled out from the rust preventive bush 5. Then, after operating the rust preventive bushing 5 in the expanded state by the reduced diameter operating means D provided in the pipe joint A to a reduced diameter state that can be inserted and mounted in the branch port 4 against its elastic restoring force, When the hole saw 9 of the drilling machine C that also constitutes the pushing means E is moved again to the fluid transport pipe 1 side, the tip of the hole saw 9 is in contact with the receiving portion 5b of the rust-proof bushing 5 in the reduced diameter state. Touching from the direction, the rust preventive bush 5 is pushed into the predetermined mounting position of the branch port 4.
[0056]
The engaging concave portion 19 on the rust prevention bush 5 side which is one constituent member of the temporary fixing means F is an engaging concave portion which is the other constituent member of the temporary fixing means F formed on the inner wall portion 2b of the branch pipe portion 2. 18, when the rust preventive bush 5 reaches the predetermined mounting position, as shown in FIG. 10 (c), it contacts the periphery of the branch port 4 on the outer peripheral surface of the fluid transport pipe 1 from the perforation axis Y direction. Further, the push-in movement of the rust prevention bush 5 is prevented. At this time, the driving part of the drilling machine A is driven in reverse or the manual handle is operated to move the hole saw 9 back to the initial standby position.
[0057]
Therefore, a special structure for configuring the pushing means E is unnecessary, and the rust preventive bush 5 can be pushed to the predetermined mounting position of the branch port 4 using the feed mechanism of the drilling machine C. Not only can the pipe joint structure be simplified and the construction cost can be reduced, but also the construction period and labor can be reduced.
In addition, since the other structure is the same as the structure demonstrated in 1st Embodiment, the same number is attached to the same structure location as 1st Embodiment, and the description is abbreviate | omitted.
[0058]
[Third Embodiment]
In the pipe joint shown in FIG. 11, the rust preventive bush 5 pushed into the predetermined mounting position of the branch port 4 is contracted while allowing the mounting movement of the rust preventive bush 5 in the reduced diameter state to the branch port 4 side. With the release operation of the diameter reducing operation force by the diameter operating means D, it was elastically deformed to the diameter expansion side by its elastic restoring force until it was in close contact with the inner peripheral surface 1a of the tube wall portion facing the branch port 4. At this time, an extraction preventing means 30 for preventing the rust prevention bush 5 from moving out is provided.
[0059]
The extraction preventing means 30 is a portion corresponding to the rear end of the anticorrosion bush 5 pushed into a predetermined mounting position of the branch port 4 at a plurality of locations in the circumferential direction of the inner wall portion 2b of the branch pipe portion 2 or the entire circumferential region. Furthermore, as shown in FIG. 11 (a), when the rust prevention bush 5 is operated in a reduced diameter state, the protrusion margin that does not come into contact with the rear end side receiving portion 5b which is the maximum outer diameter portion of the rust prevention bush 5 is shown. In other words, the rust preventive bush 5 is formed in a protrusion allowance for mounting movement of the rust preventive bush 5 in the reduced diameter state to the branch port 4 side, and as shown in FIG. Consists of retaining protrusions that come into contact with the receiving portion 5b on the rear end side of the rust preventive bush 5 from the perforation axis Y direction when the diameter of the wall portion is expanded and deformed so as to be in close contact with the inner peripheral surface 1a of the hole. Has been.
[0060]
In addition, since the other structure is the same as the structure demonstrated in 1st Embodiment and 2nd Embodiment, the same number is attached to the same component location as each embodiment, and the description is abbreviate | omitted. .
[0061]
[Fourth Embodiment]
As shown in FIG. 12, in order to improve the covering and sealing performance between the entire outer peripheral surface of the rust preventive bush 5 and the hole inner peripheral surface 1a of the tube wall portion facing the branch port 4, the elasticity of a rubber lining layer or the like The sealing layer 12 may be formed for implementation.
The elastic seal layer 12 may be formed in a region of the outer peripheral surface of the rust prevention bush 5 that is in contact with at least the hole inner peripheral surface 1a of the tube wall portion facing the branch port 4.
In addition, since the other configuration is the same as the configuration described in the first embodiment, the same components are denoted by the same reference numerals as those in the first embodiment, and the description thereof is omitted.
[0062]
[Fifth Embodiment]
In the above-described fourth embodiment, the elastic seal layer 12 is formed with a uniform or substantially equal thickness over the entire outer peripheral surface of the rust preventive bushing 5. However, as shown in FIG. When the bush 5 is pushed to the predetermined mounting position of the branch port 4, the seal layer portions 12a and 12b in the regions corresponding to the inner and outer peripheral surfaces of the fluid transport pipe 1 are thicker than the seal layer portions in other portions. It is formed into a meat and is in close contact with the peripheral edge of the inner peripheral surface and outer peripheral surface of the fluid transport pipe 1 to enhance the retaining function of the rust prevention bush 5 and at the same time, the pipe wall facing the branch port 4 You may comprise so that the covering sealing performance between the hole inner peripheral surface 1a of a part and the outer peripheral surface of the antirust bushing 5 may be improved.
In addition, since the other structure is the same as the structure demonstrated in 1st Embodiment, the same number is attached to the same structure location as 1st Embodiment, and the description is abbreviate | omitted.
[0063]
[Other Embodiments]
(1) In the first embodiment described above, the hole saw 9 is moved back to the initial standby position, and the valve body 11 of the work gate valve B is closed and operated, and then the rust prevention bush 5 is reduced in diameter. Although the diameter reduction operation is performed at D, the diameter of the rust prevention bush 5 may be reduced by the diameter reduction operation means D when the hole saw 9 pulls out the rust prevention bush 5.
[0064]
(2) In the first embodiment described above, the diameter-reducing operation means D is constituted by a plurality of push bolts 13, but is not limited to this configuration, and the diameter of the rust-proof bushing 5 in the diameter-expanded state is reduced. Any structure may be adopted as long as it can be operated in a state.
[0065]
(3) In the first embodiment described above, the pushing means E is constituted by the operation shaft 20 and the cam-like pressing portion 21, but is not limited to this configuration, and the rust prevention in a reduced diameter state. Any structure may be adopted as long as the bush 5 can be pushed into the predetermined mounting position of the branch port 4 from the direction of the drilling axis Y.
[0066]
(4) In the first embodiment described above, the temporary fixing means F is connected to the annular engagement recess 18 formed in the inner wall 2 b of the branch pipe portion 2 and the annular engagement formed in the rust prevention bush 5. Although it comprised from the joint convex part 19, it is not limited to this structure, The anticorrosion bush 5 is the standby position in which the front-end | tip part left | separated from the outer peripheral surface of the fluid transport pipe 1, and the branch pipe part 2 Any structure may be adopted as long as it can be temporarily fixed and held concentrically or substantially concentrically.
[0067]
(5) The antirust bushing 5 is a stretchable elastic membrane that is connected in a sealed state between a metal cylindrical bushing body cut at one circumferential direction and between both ends of the bushing body. And the outer surface of the bushing body and the outer surface of the elastic film body have a perfect circle shape or a substantially perfect circle shape corresponding to the inner diameter of the branch port 4 when the rust prevention bush 5 is in the mounted state. It may be configured.
[Brief description of the drawings]
FIG. 1 is a partial cross-sectional side view of a whole before drilling work showing a first embodiment of the present invention.
FIG. 2 is a partial sectional side view of the whole during drilling work.
3 is an enlarged sectional view taken along line III-III in FIG.
4 is an enlarged sectional view taken along line IV-IV in FIG.
FIG. 5 is an enlarged cross-sectional side view of the main part after drilling work.
FIGS. 6A to 6D are cross-sectional side views of main parts showing a process of attaching a rust preventive bush.
FIG. 7 is a cross-sectional side view of an essential part when a rust prevention bush is pushed into a predetermined mounting position.
FIG. 8 is an enlarged plan view of the main part when the operating shaft of the pushing means is fixed by the locking means.
FIG. 9 shows the relationship between the rust prevention bush and the diameter reducing means;
(A) is a cross-sectional front view of the main part when the rust-proof bushing is in a reduced diameter state
(B) is a cross-sectional front view of the main part when the rust-proof bushing is in the mounted state
FIG. 10 shows a second embodiment of the present invention, in which (a) to (c) are cross-sectional side views of the main part showing the mounting process of the rust prevention bush.
11A and 11B show a third embodiment of the present invention, in which FIGS. 11A and 12B are cross-sectional side views of main parts showing a process of attaching a rust prevention bush.
FIG. 12 is an enlarged cross-sectional side view of an essential part showing a fourth embodiment of the present invention.
FIG. 13 is an enlarged cross-sectional side view of an essential part showing a fifth embodiment of the present invention.
FIG. 14 is a cross-sectional side view of an essential part showing a conventional method of attaching a rust prevention bush to a pipe branch port
[Explanation of symbols]
A Pipe fitting
C Drilling machine
D Reduced diameter operation means
E Pushing means
F Temporary fixing means
G Locking means
Y Drilling axis
1 Fluid transport pipe
1a Hole inner peripheral surface
2 Branch pipe section
3 Sealing material
4 Branch
5 Rust prevention bush
5a Cam surface
5b receiving part
6 Fitting body
9 Cutter (hole saw)
18 Engaging recess
19 Engaging projection
21 Pressing part

Claims

A pipe joint provided with a branch pipe part is externally fixed to the outer peripheral surface of the fluid transport pipe with a sealing material interposed therebetween, and a cutter of a punching machine attached to the branch pipe part side of this pipe joint is used. After the branch port is formed through the tube wall part that is sealed with a sealing material through the branch pipe part, the rust preventive bush is attached to the pipe wall part facing the branch port in close contact with the pipe branch port. A method of mounting a rust-proof bush,
In the branch pipe portion of the pipe joint, the branch port from the diameter-expanded state that can be tightly attached to the inner peripheral surface of the hole of the tube wall portion with elastic restoring force and allows the cutter of the drilling machine forming the branch port to pass through. A rust-proof bushing that can be elastically deformed into a reduced diameter state that can be inserted into and mounted on is assembled in advance in the expanded diameter state, and after being drilled by the cutter of the drilling machine, the reduced diameter operation means provided in the pipe joint is used to reduce the diameter. After operating a certain rust-proof bushing in a reduced diameter state, the rust-proof bushing in the reduced diameter state is pushed into a predetermined mounting position of the branch port by pushing means, and the diameter reducing operation force by the diameter reducing operation means is released to prevent A method of attaching a rust-proof bushing to a pipe branch port configured to be in close contact with the inner peripheral surface of a hole in a pipe wall portion by the elastic restoring force of the rust bushing.

The rear end portion of the rust prevention bush is formed with a receiving portion that comes into contact with the cutter of the drilling machine from the drilling axial direction when in a reduced diameter state, and the pushing means is also used as a cutter of the drilling machine. The method of attaching a rust preventive bush to the pipe branch port according to claim 1 which is configured.

It can communicate with a branch port penetrating and formed in a pipe wall part sealed with a sealing material to a joint body fixed to the exterior with a sealing material interposed between the outer peripheral surface of the fluid transport pipe and the pipe A pipe joint in which a branch pipe part is formed,
In the branch pipe portion, a shrinkage that can be attached tightly to the inner peripheral surface of the hole of the pipe wall portion facing the branch port with an elastic restoring force and that can be inserted into the branch port from a diameter-expanded state larger than the branch port. A rust preventive bush that is elastically deformable in a diameter state is assembled in a diameter expanded state, and the joint body has a diameter reducing operation means for operating the rust preventive bush in a diameter expanded state to a diameter reduced state, A pipe joint provided with pushing means for pushing the rust-proof bushing in a reduced diameter state into a predetermined mounting position of the branch port from the direction of the drilling axis.

At the portion where the inner wall portion of the branch pipe portion and the rust prevention bush are opposed to each other in the radial direction, the tip portion of the rust prevention bush is at a standby position away from the outer peripheral surface of the fluid transport pipe and is concentric with the branch pipe portion. 4. A pipe joint according to claim 3, wherein a temporary fixing means for temporarily fixing and holding the substantially concentric state is provided.

The pushing means is provided with a pressing portion that presses the rear end portion of the rust preventive bush provided in the branch pipe portion toward the branch port side, and the operation for pressing the rust preventive bush into a predetermined mounting position of the branch port. The pipe joint according to claim 3 or 4, wherein a lock means for fixing the pressing portion at a position is provided.

The pushing means includes a pressing action position for pressing the rear end portion of the rust prevention bush provided in the branch pipe portion toward the branch port side, and a storage position moved radially outward from the outer peripheral surface of the rust prevention bush. The pipe joint according to claim 3, 4 or 5, wherein a pressing portion that can be switched between and is provided.

The temporary fixing means is engaged with the engagement concave portion formed in the inner wall portion of the branch pipe portion, and engages with the engagement concave portion to regulate the relative movement in the perforation axis direction between the branch pipe portion and the rust prevention bush, The pipe joint according to claim 4, further comprising an engaging convex portion formed on the rust-proof bush so as to be movable through the engaging concave portion when a certain operating force is applied.

The engagement convex portion of the temporary fixing means is configured as a contact portion that comes into contact with the periphery of the branch port of the fluid transport pipe from the perforation axis direction when the rust preventive bush is pushed into a predetermined mounting position of the branch port. Item 8. The pipe joint according to Item 7.

The rust preventive bush is configured in a cylindrical shape with one circumferential direction cut, and cam surfaces that are guided to move to a superposed state in accordance with elastic deformation from the enlarged diameter state to the reduced diameter state at both ends thereof When the rust-proof bushing is in a mounted state, the cam surfaces of the both end portions are in contact with each other, and the outer peripheral surface becomes a perfect circle shape or a substantially perfect circle shape corresponding to the inner diameter of the branch port. The pipe joint according to any one of claims 3 to 8, which is configured as described above.