JP2004125735A

JP2004125735A - Leakage test method and leakage test device used therefor

Info

Publication number: JP2004125735A
Application number: JP2002293674A
Authority: JP
Inventors: Nobuyuki Onishi; 大西　伸幸; Takeshi Hashimoto; 橋本　猛
Original assignee: Osaka Gas Co Ltd
Current assignee: Osaka Gas Co Ltd
Priority date: 2002-10-07
Filing date: 2002-10-07
Publication date: 2004-04-22
Anticipated expiration: 2022-10-07
Also published as: JP3935040B2

Abstract

<P>PROBLEM TO BE SOLVED: To enable the leakage test without necessity for going indoors, and eliminate the trouble of replacing air with fuel gas by purging. <P>SOLUTION: In the leakage test of a gas pipe 1 between a gas meter 2 and an indoor end, fuel gas is charged, at a higher pressure than the normal feed pressure of fuel gas, from an outlet side connecting opening 7 of the gas pipe 1 connected to an outlet of the gas meter 2 into a test section of the gas pipe 1, and the pressure of the fuel gas charged is monitored from the side of the outlet connecting opening 7, thereby checking out the leakage of the fuel gas. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、ガスメータを交換したり、配管施工したり、配管の点検をしたりするときガスメータから屋内までのガス配管の漏洩検査を行うガス配管の漏洩検査方法及び漏洩検査装置に関するものである。
【０００２】
【従来の技術】
一般に、ガスメータを交換したり、配管施工したり、配管の点検をしたりするときガス配管に漏れがないかを確認するする必要がある。その確認方法としてはガス配管内の所定圧力に加圧し、その圧力減少がないことを確認する（屋内に供給する燃焼ガスの供給圧力を使って漏れがないことを確認する場合もあるが、通常、都市ガス等の燃料ガスの供給圧力は低圧で大気圧と余り差圧がなく、漏れがあっても圧力降下が小さいため、漏れを確認するのに長時間かかるものであり、ここでは都市ガス等の燃料ガスの供給圧力による漏れの検査方法でなく、より積極的に周囲の大気圧と圧力差を生じさせ、有意に漏洩が確認できるように加圧して行う検査方法を対象とする。）。
【０００３】
ガス配管内を加圧しているとき、仮に漏れがあれば、圧力はその漏れ量に比例した圧力降下を起こし、漏れが目視（水柱やゲージによる）あるいは電子的（例えは、圧力に応じて信号を出力する圧力計の出力を集積回路等で判定する。）に確認され、本来なら目にみえない漏れという現象を確認することができる。このようにガス配管内部を加圧してその圧力降下の監視により漏れの有無を確認する方法を漏洩検査と呼ぶが、これらガス配管の漏洩検査をする場合、ガス配管の検査する区間に何らかの流体を加圧して投入する必要がある。
【０００４】
図９に従来の漏洩検査の一例を示す。ガス配管１は供給源側（都市ガスの場合ガス会社の本管、ＬＰガスの場合ボンベ）から屋内の末端まで配管してあり、このガス配管１の途中にガスメータ２を配置してある。ガスメータ２より上流側の部分でガス配管１には管路を開閉する供給側元栓３を装着してあり、ガス配管１の屋内側の末端のガス取り出し口４に取り出し側元栓５を装着してある。屋内では一般にガス配管１が複数に分岐してあり、複数のガス取り出し口４が設けられていると共に各ガス取り出し口４に取り出し側元栓５が設けられている。ガス取り出し口４にはガス器具６が接続されている。漏洩検査装置Ａ′は例えばＴ字状の３つの接続口ａ，ｂ，ｃを有すると共に２つの開閉弁ｄ，ｅを有する三方弁部材ｆと圧力計ｇと手動式の加圧ポンプｈとで構成されており、接続口ｂに圧力計ｇが接続され、接続口ｃに加圧ポンプｈが接続されている。この漏洩検査装置Ａ′でガス配管１の供給側元栓３とガス取り出し口４との間の検査区間の検査をするとき、接続口ａを接続ホースｉ等を介してガス取り出し口４に接続し、供給側元栓３を閉じると共に漏洩検査装置Ａ′を接続したガス取り出し口４の取り出し側元栓５を開き、開閉弁ｄを閉じると共に開閉弁ｅを開き、加圧ポンプｈを操作して空気を加圧してガス配管１の検査する区間に充填して所定圧力に加圧し、その後開閉弁ｄを開くと共に開閉弁ｅを閉じ、圧力計ｇで圧力変化を監視して漏洩の有無を確認する。ガス配管１の漏洩がないことを確認すると、漏洩検査装置Ａ′を外し、ガス配管１に充填した空気をパージして燃料ガスと入れ替え、取り出し側元栓５を閉じる。
【０００５】
上記従来例では屋内で漏洩検査装置Ａ′をガス取り出し口４に接続して屋内から漏洩検査をしているが、屋外で漏洩検査装置Ａ′を接続して漏洩検査する方法もある。この場合、ガスメータ２を外し、ガスメータ２の出口に接続する出口側接続口７に上記漏洩検査装置Ａ′の接続口ａを接続し、上記と同様に加圧ポンプｈにて空気を加圧してガス配管１の検査区間に圧入し、上記と同様に漏洩検査を行っている（例えば、特許文献１参照）。
【０００６】
また図１０に従来の漏洩検査の他の例を示す。この例の漏洩検査装置Ａ″は上記漏洩検査装置Ａ′の加圧ポンプに代えて加圧用ボンベｊを設けてあり、加圧用ボンベｊに屋内に供給する燃料ガスと同じ種類のガスを加圧充填してある。そしてこの漏洩検査装置Ａ″でガス配管１の供給側元栓３とガス取り出し口４との間の検査区間の検査をするとき、接続口ａを接続ホースｉ等を介してガス取り出し口４に接続し、供給側元栓３を閉じると共に漏洩検査装置Ａ″を接続したガス取り出し口４の取り出し側元栓５を開き、加圧用ボンベｊから燃料ガスをガス配管１の検査区間に充填して所定圧力に加圧し、その後圧力計ｇで圧力変化を監視して漏洩の有無を確認する。そして漏洩がないことを確認した後に漏洩検査装置Ａ″を取り外し、取り出し用元栓５を閉じる（例えば特許文献２参照）。
【０００７】
【特許文献１】
特開２０００−３３７９４２号公報
【特許文献２】
特開平１０−１８５７５１号公報
【０００８】
【発明が解決しようとする課題】
ところで、上記の図９に示す従来例では屋内に入って屋内のガス取り出し口４に漏洩検査装置Ａ′を接続して検査しなければならなく、検査員が屋内に立ち入らなければ検査できない。このためガス取り出し口４がある屋内が住戸の場合、検査のために住戸内に検査員を入れる必要があり、住居者から見れば、プライベートな場所を見られるなどの不快を感じられることがある。またガス配管１の検査区間に空気を加圧して充填して検査するため、検査を終えた後にガス配管１の空気をパージして供給する燃料ガスと置換する必要があり、この作業に手間がかかるという問題がある。
【０００９】
またガスメータ２を取り外してこのガスメータ２の接続箇所で漏洩検査装置Ａ′を接続して検査する場合、屋内に入らなくても検査することができるが、漏洩検査をした後、ガス配管１の空気をパージして供給する燃料ガスと置換する必要があり、この作業に手間がかかるという問題がある。また漏洩検査のときには屋内に立ち入らなくてもできるが、空気をパージして燃料ガスと置換するときには屋内に立ち入らなければならないという問題がある。
【００１０】
また上記の図１０に示す従来例でも屋内のガス取り出し口４に漏洩検査装置Ａ″を接続して検査しなければならなく、検査員が屋内に立ち入らなければ検査できないという問題がある。この従来例の場合、加圧用ボンベｊから燃料ガスを充填してガス配管１の検査区間を加圧するため、検査後に空気をパージして燃料ガスと置換する手間を必要としなくなるが、漏洩検査装置Ａ″は加圧用ボンベｊ（実用上では、市販のスプレー缶のようなものでは十分に加圧できる容量がなく、１０リットル以上且つ、０．１Ｍｐａ以上のボンベ）を有するために重い加圧用ボンベｊを持ち運ばなければならなく、漏洩検査装置Ａ″の取り扱いがしにくいと共に労力を要するという問題がある。
【００１１】
本発明は上記の点に鑑みてなされたものであり、屋内に入らなくても漏洩検査ができ、しかも検査後に空気をパージして燃料ガスと置換する手間を要しないようにできるガス配管の漏洩検査方法及びそれに用いる漏洩検査装置を提供することを課題とするものである。
【００１２】
【課題を解決するための手段】
上記課題を解決するための本発明のガス配管の漏洩検査方法は、ガスメータ２と屋内の末端との間のガス配管１の漏洩を検査するにあたって、ガスメータ２の出口に接続するガス配管１の出口側接続口７からガス配管１の検査区間内に燃料ガスを通常の燃料ガスの供給圧力より高い圧力で充填し、上記充填をした燃料ガスの圧力を出口側接続口７側から監視することで燃料ガスの漏洩の有無を検査することを特徴とする。
【００１３】
上記のようにガスメータ２を設置してある屋外で出口側接続口７から燃料ガスを充填すると共にこの充填した燃料ガスの圧力を出口側接続口７側で監視して漏洩を検査するためにガスメータ２の設置箇所から検査できて屋内に立ち入らないで検査できる。またガス配管１に燃料ガスを充填して検査するために漏洩検査後に空気をパージして燃料ガスと置換する手間を要しないと共にこの作業をするために屋内に立ち入ることも必要なくなる。
【００１４】
また上記漏洩検査方法において、ガスメータ２のガスの入口に接続するガス配管１の入口側接続口８から上記出口側接続口７を介してガス配管１の検査区間内に燃料ガスを加圧して送入することで通常の燃料ガス供給圧力より高い圧力で充填することを特徴とすることも好ましい。
【００１５】
この場合、ガス供給源から供給される燃料ガスを加圧して充填することで検査するために加圧用ボンベから燃料ガスを供給するもののように重い加圧用ボンベの取り扱いを要せず、検査が容易にできる。
【００１６】
また本発明のガス配管の漏洩検査装置Ａはガスメータ２の入口に接続するガス配管１の入口側接続口８とガスメータ２の出口に接続する出口側接続口７との間に配置する管路９と、管路９の一端に設けられて入口側接続口８に接続し得る入口側被接続口１０と、管路９の他端に設けられて出口側接続口７に接続し得る出口側被接続口１１と、管路９の途中に設けられて燃料ガスを加圧する加圧手段１２と、加圧手段１２と出口側被接続口１１との間で管路９に連通するように配置されて管路９内の圧力を監視する圧力監視手段１３と、加圧手段１２と圧力監視手段１３との間で管路９に設けられて管路９を開閉する管路開閉手段１４と、管路開閉手段１４と出口側被接続口１１との間で管路９に連通するように配置されて管路９内の空気を外に抜くための抜き管１５と、抜き管１５に配置されて抜き管１５を開閉する抜き管用開閉弁１６とを具備したことを特徴とする。
【００１７】
上記漏洩検査装置Ａで検査する場合、ガスメータ２を取り外した部分に漏洩検査装置Ａを配置して入口側被接続口１０をガス配管１の入口側接続口８に接続すると共に出口側被接続口１１をガス配管１の出口側接続口７に接続し、管路開閉手段１４を開くと共に抜き管用開閉弁１６を開き、入口側接続口８から燃料ガスを供給して抜き管１５から管路９内の空気をパージすると共に燃料ガスと置換し、抜き管用開閉弁１６を閉じて加圧手段１２で加圧してガス配管１の検査区間に加圧した燃料ガスを充填し、検査区間を所定の圧力に加圧した状態で管路開閉手段１４を閉じ、圧力監視手段１３で所定の時間圧力を監視して漏洩の有無の検査をする。検査を終えると、漏洩検査装置Ａを取り外してガスメータ２を取り付ける。上記のようにガスメータ２を取り付ける箇所に漏洩検査装置Ａを取り付け検査するために屋外で漏洩検査をすることができて屋内に立ち入ることなく検査を行うことができる。また燃料ガスをガス配管１の検査区間に充填して検査するために検査後に空気をパージして燃料ガスと置換する手間を要しないと共にこの作業をするために屋内に立ち入ることも必要なくなる。またガス配管１の入口側接続口８から供給される燃料ガスを加圧手段１２で加圧して充填するので加圧用ボンベから燃料ガスを供給するもののように重い加圧用ボンベの取り扱いを要せず、検査が容易にできる。またガス配管１の検査区間に燃料ガスを加圧して充填する前に漏洩検査装置Ａの管路９内の空気を抜き管１５からパージして燃料ガスと置換するので、ガス配管１の検査区間に空気が入り込む弊害を防止できる。
【００１８】
また上記漏洩検査装置Ａにおいて、出口側被接続口１１に管路９を開閉する出口側開閉弁１７を配置したことを特徴とすることも好ましい。この場合、抜き管用開閉弁１６を開いて管路９の空気をパージするとき出口側開閉弁１７を閉じておくことで空気がガス配管１の検査区間に流入するのを防止でき、空気をパージした後に抜き管用開閉弁１６を閉じて出口側開閉弁１７を開くことにより燃料ガスをガス配管１の検査区間に加圧充填できる。これによりガス配管１の検査区間に空気が入り込む弊害を一層防止できる。
【００１９】
また上記漏洩検査装置において、所定以下の圧力では気体が流れるのを阻止すると共に所定以上の圧力では気体が流れるようにする通気規制部１８を出口側被接続口１１に設けたことを特徴とすることも好ましい。この場合、抜き管用開閉弁１６を開いて管路９の空気をパージするとき空気が通気規制部１８でガス配管１の検査区間に流入するのを防止でき、空気をパージした後、抜き管用開閉弁１６を閉じることより通気規制部１８に燃料ガスを通過させてガス配管１の検査区間に燃料ガスを加圧充填できる。これによりガス配管１の検査区間に空気が入り込む弊害を一層防止できる。また上記のように出口側開閉弁１７を設けるもののように弁の開閉操作を必要としなくて取り扱いが簡単になる。
【００２０】
【発明の実施の形態】
図１に示すようにガス配管１は供給源側（都市ガスの場合ガス会社の本管、ＬＰガスの場合ボンベ）から住戸等の屋内の末端まで配管してあり、このガス配管１の途中にガスメータ２を配置してある。ガスメータ２より上流側の部分でガス配管１には管路を開閉する供給側元栓３を装着してあり、ガス配管１の屋内側の末端のガス取り出し口４に取り出し側元栓５を装着してある。屋内では一般にガス配管１が複数に分岐してあり、複数のガス取り出し口４が設けられていると共に各ガス取り出し口４に取り出し側元栓５が設けられている。ガス取り出し口４にはガス器具６が接続されている。ガスメータ２の入口にはガス配管１の入口側接続口８を袋ナット等で着脱可能に接続してあり、ガスメータ２の出口にはガス配管１の出口側接続口７を袋ナット等で着脱可能に接続してある。
【００２１】
このガス配管１の漏洩検査装置Ａは例えば図３に示すように構成されている。ガスを流通させることができる管路９の一端には入口側被接続口１０を設けてあって、この入口側被接続口１０が上記ガス配管１の入口側接続口８に着脱可能に接続し得るようになっており、管路９の他端には出口側被接続口１１が設けてあって、この出口側被接続口１１が上記ガス配管の１の出口側接続口７に着脱可能に接続し得るようにしてある。この管路９の途中には加圧手段１２を配置してあり、管路９内の流体を加圧して送ることができるようになっている。かかる加圧手段１２は本例の場合、内部が中空の弾性ボール体２０に逆止弁２１を設けて形成されており、弾性ボール体２０の握り操作を繰り返すことにより手動で流体を加圧して送ることができるようになっている。本例の場合、２連の弾性ボール体２０を設けてあり、高い圧力に加圧できるようになっている。また管路９には管路９を開閉する管路開閉手段１４が設けられるが、この管路開閉手段１４は本例の場合管路開閉弁１４ａであり、加圧手段１２より出口側被接続口１１側で管路９に管路開閉弁１４ａを配置してある。管路９の出口側被接続口１１の位置に管路９を開閉する出口側開閉弁１７を配置してある。管路開閉弁１４ａと出口側開閉弁１７との間で管路９に連通するように管路９内の圧力を監視する圧力監視手段１３を設けてある。この圧力監視手段１３は例えばデジタルマノメータと称されるもので電子的に圧力を監視できるようになっている。本例の場合、圧力監視手段１３と管路９とを連通させる連通管２２に開閉する圧力監視用開閉弁２３を配置してある。出口側開閉弁１７より僅かに管路開閉弁１４ａ側の位置には管路９から分岐した抜き管１５を分岐してあり、抜き管１５にて管路９内の空気をパージすることができるようになっている。この抜き管１５は抜き管１５を開閉する抜き管用開閉弁１６を設けてある。
【００２２】
上記のように構成せる漏洩検査装置Ａを用いてガス配管１の漏洩検査を次のように行う。なお、本例ではガス配管１の出口側接続口７と取り出し側元栓５との間の区間を検査する。まず、図１の状態で供給側元栓３を閉めてガスの供給を遮断し、入口側接続口８や出口側接続口７の接続を外してガスメータ２を取り外す。次にガスメータ２を取り外した位置に漏洩検査装置Ａを配置し、漏洩検査装置Ａの入口側被接続口１０とガス配管１の入口側接続口８とを接続すると共に漏洩検査装置Ａの出口側被接続口１１とガス配管１の出口側接続口７とを接続して図２のように漏洩検査装置Ａを取り付ける。この状態では管路開閉弁１４ａ及び圧力監視用開閉弁２３を開いてあり、出口側開閉弁１７及び抜き管用開閉弁１６を閉じてある。漏洩検査装置Ａを取り付けた後、供給側元栓３を開いて抜き管用開閉弁１６を開く。すると、入口側接続口８から通常のガス供給圧で燃料ガスが管路９内に供給され、管路９内の空気は抜き管１５からパージされて管路９の空気が燃料ガスと置換される。このとき出口側開閉弁１７を閉じてあるために空気がガス配管１の検査区間に流入するのが防止される。抜き管１５から空気がパージされると抜き管用開閉弁１６を閉じで出口側開閉弁１７を開く。次いで加圧手段１２で加圧して燃料ガスをガス配管１の検査区間に充填して所定の圧力（通常の燃料ガスの供給圧より十分に高い圧力、例えばガスの供給圧が通常２ｋＰａであるのに対して７〜８ｋＰａ）まで加圧する。この所定の圧力まで加圧すると、供給側元栓３及び管路開閉弁１４ａを閉じて、圧力監視手段１３で圧力変動を所定の時間監視して漏洩の有無を確認する。
【００２３】
漏洩の有無の検査を完了すると、抜き管用開閉弁１６を開いて圧力を下げ、出口側開閉弁１７を閉じる。次いで漏洩検査装置Ａの入口側被接続口１０とガス配管１の入口側接続口８との接続を外すと共に漏洩検査装置Ａの出口側被接続口１１とガス配管１の出口側接続口７との接続を外して漏洩検査装置Ａを取り外す。このとき、空気の流入を防ぐために入口側接続口８や出口側接続口７をゴム栓で閉塞する。次いでガスメータ２を図１のように取り付ける。
【００２４】
上記のようにしてガス配管１の漏洩の検査をするが、ガスメータ２の設置箇所に漏洩検査装置Ａを取り付け、この箇所から燃料ガスを加圧して充填すると共にこの箇所で圧力を監視して漏洩の検査を行うために住戸等の屋内に立ち入らなくても検査できる。また燃料ガスをガス配管１に加圧充填して検査を行うために空気を充填するもののように検査後にガス配管１の空気をパージして燃料ガスと置換する必要がなくなり、このような手間を要しないと共にこの操作をするのに住戸等の屋内に立ち入る必要がなくなる。またガス配管１に加圧充填する燃焼ガスはガスメータ２より上流側から供給される燃料ガスを加圧手段１２で加圧して供給するものであるために、従来のように加圧用ボンベ等を要しなく、取り扱いが簡便に行える。またガス配管１に燃料ガスを加圧充填する前に抜き管１５から空気をパージして燃料ガスに置換するために管路９に空気があってもガス配管１に空気が流入してしまう弊害を防止できる。
【００２５】
なお、上記の例では抜き管１５と管路開閉弁１４ａとの間で管路９に連通管２２を接続して圧力監視手段１３により監視するようにしたが、この圧力監視手段１３を連通管２２により抜き管用開閉弁１６と取り外し自在なように接続すると、抜き管１５と管路開閉弁１４ａとの間で分岐するように連通管２２を接続する必要がなく、抜き管１５を分岐した部分で圧力監視をすることできる。つまり、抜き管１５から空気をパージした後、抜き管用開閉弁１６に連通管２２を接続することで圧力監視手段１３にて圧力監視できる。このようにすると管路構造を簡単にできると共に開閉弁を兼用して部品点数を少なくできる。
【００２６】
また図４は漏洩検査装置Ａの他の例を示すものである。本例のものも上記例と基本的に同じであるが、上記のものと加圧手段１２が異なる。本例の場合、シリンダ式の手動ポンプであって、管路９と連通するシリンダ２５と、シリンダ２５内に摺動自在に配置したピストン２６と、ピストン２６を往復させる操作ロッド２７と、シリンダ２５の流入側及び流出側に設けた逆止弁２８とで構成されている。
【００２７】
また管路開閉手段１４は管路９の圧力を保持する目的で設けられるが、加圧手段１２の逆流を防止する目的の逆止弁２８等が管路９の圧力を保持する管路開閉手段１４の働きをするならばこの逆止弁２８等を管路開閉手段１４とできる。従って上記の例のように別途管路開閉弁１４ａのような管路開閉手段１４を設ける必要がなく、このような開閉手段は省略できる。但し、その場合、加圧手段１２が圧力により変形したり、また駆動部分が動いたりし、その結果、圧力変動が起こるおそれがあるが、上記のように逆止弁２８に管路開閉手段１４の働きをさせる場合、上記圧力変動を防止する手段を（例えば手動部分のストッパーなど）が必要となる場合がある。また、上記図４の例の場合、操作ロッド２７を固定するストッパーを設けることにより圧力変動を防止でき、逆止弁２８を管路開閉手段１４と兼用でき、別途管路開閉手段１４を設ける必要がない。
【００２８】
また図５は漏洩検査装置Ａの他の例を示すものである。本例のものも上記例と基本的に同じであるが、上記の例の出口側開閉弁１７を設ける代わりに通気規制部１８を設けた点が異なる。この通気規制部１８は所定以下の圧力では気体が流れるのを阻止すると共に所定以上の圧力では気体が流れるように気体の流れを規制するものである。つまり、抜き管用開閉弁１６を開いて管路９の空気を抜き管１５からパージするときは通気規制部１８に所定以下の圧力しかかからなくて通気規制部１８に空気が通気されないが、抜き管用開閉弁１６を閉じて加圧した燃料ガスを送ったとき通気規制部１８を燃料ガスが通過してガス配管１に燃料ガスが充填されるようになっている。従って抜き管用開閉弁１６を開いて管路９の空気をパージするとき空気が通気規制部１８でガス配管１の検査区間に流入するのを防止でき、これによりガス配管１の検査区間に空気が入り込む弊害を一層防止できる。また上記のように出口側開閉弁１７を設けるもののように弁の開閉操作を必要としなくて取り扱いが簡単になる。
【００２９】
上記通気規制部１８は図６（ａ）（ｂ）のように２枚の板状体３０を僅かな隙間を介して重ねてこれらで通路を塞ぐように構成しても、図７に示すような多孔質材３１で構成しても、図８（ａ）（ｂ）に示すように管状集合体３２で構成してもよい。
【００３０】
なお、上記の実施の形態の例では燃料ガスをガス配管１の入口側接続口８から供給して検査区間に加圧充填する例について述べたが、燃料ガスを加圧充填した加圧用ボンベから出口側接続口７を介して検査区間に燃料ガスを供給しても本発明の検査を行うことができる。この場合、漏洩検査装置Ａに加圧手段１２を要しないが、重い加圧用ボンベを持ち運びする必要がある。
【００３１】
【発明の効果】
本発明の請求項１の発明は、ガスメータと屋内の末端との間のガス配管の漏洩を検査するにあたって、ガスメータの出口に接続するガス配管の出口側接続口からガス配管の検査区間内に燃料ガスを通常の燃料ガスの供給圧力より高い圧力で充填し、上記充填をした燃料ガスの圧力を出口側接続口側から監視することで燃料ガスの漏洩の有無を検査するので、ガスメータの設置箇所から漏洩検査できて屋内に立ち入らないで検査できるものであり、しかもガス配管に燃料ガスを充填して検査するために漏洩検査後に空気をパージして燃料ガスと置換する手間を要しないと共にこの作業をするために屋内に立ち入ることも必要なくなるものである。
【００３２】
また本発明の請求項２の発明は、請求項１において、ガスメータのガスの入口に接続するガス配管の入口側接続口から上記出口側接続口を介してガス配管の検査区間内に燃料ガスを加圧して送入することで通常の燃料ガス供給圧力より高い圧力で充填するので、ガス供給源から供給される燃料ガスを加圧して充填することで検査するために加圧用ボンベから燃料ガスを供給するもののように重い加圧用ボンベの取り扱いを要せず、検査が容易にできるものである。
【００３３】
また本発明の請求項３の発明は、ガスメータの入口に接続するガス配管の入口側接続口とガスメータの出口に接続する出口側接続口との間に配置する管路と、管路の一端に設けられて入口側接続口に接続し得る入口側被接続口と、管路の他端に設けられて出口側接続口に接続し得る出口側被接続口と、管路の途中に設けられて燃料ガスを加圧する加圧手段と、加圧手段と出口側被接続口との間で管路に連通するように配置されて管路内の圧力を監視する圧力監視手段と、加圧手段と圧力監視手段との間で管路に設けられて管路を開閉する管路開閉手段と、管路開閉手段と出口側被接続口との間で管路に連通するように配置されて管路内の空気を外に抜くための抜き管と、抜き管に配置されて抜き管を開閉する抜き管用開閉弁とを具備した漏洩検査装置であるので、ガスメータを取り外した部分に漏洩検査装置を配置して入口側被接続口をガス配管の入口側接続口に接続すると共に出口側被接続口をガス配管の出口側接続口に接続し、管路開閉手段を開くと共に抜き管用開閉弁を開き、入口側接続口から燃料ガスを供給して抜き管から管路内の空気をパージすると共に燃料ガスと置換し、抜き管用開閉弁を閉じて加圧手段で加圧してガス配管の検査区間に加圧した燃料ガスを充填し、検査区間を所定の圧力に加圧した状態で管路開閉手段を閉じ、圧力監視手段で所定の時間圧力を監視して漏洩の有無の検査をすることができるものであって、上記のようにガスメータを取り付ける箇所に漏洩検査装置を取り付けて検査するために屋外で漏洩検査をすることができて屋内に立ち入ることなく検査を行うことができるものであり、しかも燃料ガスをガス配管の検査区間に充填して検査するために検査後に空気をパージして燃料ガスと置換する手間を要しないと共にこの作業をするために屋内に立ち入ることも必要なくなるものであり、さらにガス配管の入口側接続口から供給される燃料ガスを加圧手段で加圧して充填するので加圧用ボンベから燃料ガスを供給するもののように重い加圧用ボンベの取り扱いを要せず、検査が容易にできるものであり、さらにまたガス配管の検査区間に燃料ガスを加圧して充填する前に漏洩検査装置の管路内の空気を抜き管からパージして燃料ガスと置換するので、ガス配管の検査区間に空気が入り込む弊害を一層防止できるものである。
【００３４】
また本発明の請求項４の発明は、請求項３において、出口側被接続口に管路を開閉する出口側開閉弁を配置したので、抜き管用開閉弁を開いて管路の空気をパージするとき出口側開閉弁を閉じておくことで空気がガス配管の検査区間に流入するのを防止でき、空気をパージした後に抜き管用開閉弁を閉じて出口側開閉弁を開くことにより燃料ガスをガス配管の検査区間に加圧充填できるものであって、ガス配管の検査区間に空気が入り込む弊害を一層防止できるものである。
【００３５】
また本発明の請求項５発明は、請求項３において、所定以下の圧力では気体が流れるのを阻止すると共に所定以上の圧力では気体が流れるようにする通気規制部を出口側被接続口に設けたので、抜き管用開閉弁を開いて管路の空気をパージするとき空気が通気規制部でガス配管の検査区間に流入するのを防止でき、空気をパージした後、抜き管用開閉弁を閉じることより通気規制部に燃料ガスを通過させてガス配管の検査区間に燃料ガスを加圧充填できるものであって、これによりガス配管の検査区間に空気が入り込む弊害を一層防止できるものであり、また請求項４の出口側開閉弁を設けるもののように弁の開閉操作を必要としなくて取り扱いが簡単になるものである。
【図面の簡単な説明】
【図１】本発明の実施の形態の一例を説明するものでガス配管の管路図である。
【図２】同上の検査する状態を説明する一部分解管路図である。
【図３】同上の漏洩検査装置を示す正面図である。
【図４】同上の漏洩検査装置の他の例を示す正面図である。
【図５】同上の漏洩検査装置の他の例を示す正面図である。
【図６】同上の通気規制部の一例を示すもので、（ａ）は斜視図、（ｂ）は断面図である。
【図７】同上の通気規制部の他の例を示す斜視図である。
【図８】同上の通気規制部の他の例を示すもので、（ａ）は斜視図、（ｂ）は（ａ）の要部拡大図である。
【図９】（ａ）は一従来例の検査する状態の管路図、（ｂ）は（ａ）のＸ部を拡大せる一部切欠正面図、（ｃ）は（ｂ）のＹ部を拡大せる一部切欠正面図である。
【図１０】他の従来の検査の状態を説明する管路図である。
【符号の説明】
Ａ　漏洩検査装置
１　ガス配管
２　ガスメータ
７　出口側接続口
８　入口側接続口
９　管路
１０　入口側被接続口
１１　出口側被接続口
１２　加圧手段
１３　圧力監視手段
１４　管路開閉手段
１４ａ　管路開閉弁
１５　抜き管
１６　抜き管用開閉弁
１７　出口側開閉弁
１８　通気規制部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a gas pipe leak inspection method and a leak inspection apparatus for performing a leak inspection of a gas pipe from a gas meter to a room indoors when replacing a gas meter, constructing a pipe, or checking a pipe.
[0002]
[Prior art]
Generally, when replacing a gas meter, constructing a pipe, or inspecting a pipe, it is necessary to confirm that there is no leak in the gas pipe. As a confirmation method, pressurize to a predetermined pressure in the gas pipe and confirm that there is no decrease in pressure. (In some cases, it is confirmed that there is no leakage using the supply pressure of the combustion gas supplied indoors. The supply pressure of fuel gas such as city gas is low and there is not much pressure difference from atmospheric pressure. Even if there is a leak, the pressure drop is small, so it takes a long time to confirm the leak. It is not intended to test for leaks caused by the supply pressure of fuel gas, etc., but to apply a test method in which a pressure difference is more positively generated with the surrounding atmospheric pressure and pressure is applied so that the leak can be confirmed significantly.) .
[0003]
If there is a leak while pressurizing the gas pipe, the pressure causes a pressure drop in proportion to the amount of the leak, and the leak is visually (by a water column or gauge) or electronic (for example, a signal is generated according to the pressure. Is determined by an integrated circuit or the like.), And the phenomenon of leakage that is originally invisible can be confirmed. The method of confirming the presence or absence of leakage by monitoring the pressure drop by pressurizing the inside of the gas pipe in this way is called a leak test. It is necessary to feed under pressure.
[0004]
FIG. 9 shows an example of a conventional leak inspection. The gas pipe 1 is piped from the supply source side (the main pipe of the gas company in the case of city gas, the cylinder in the case of LP gas) to the indoor end, and the gas meter 2 is arranged in the gas pipe 1. A supply side main plug 3 for opening and closing a pipe is mounted on the gas pipe 1 at a portion upstream of the gas meter 2, and a take-out side main plug 5 is mounted on a gas take-out port 4 at an end of the gas pipe 1 on the indoor side. is there. In a room, the gas pipe 1 is generally branched into a plurality of branches, a plurality of gas outlets 4 are provided, and an outlet side main plug 5 is provided at each gas outlet 4. A gas appliance 6 is connected to the gas outlet 4. The leak inspection device A 'includes, for example, a three-way valve member f having three T-shaped connection ports a, b, and c and two on-off valves d and e, a pressure gauge g, and a manual pressure pump h. The pressure gauge g is connected to the connection port b, and the pressurizing pump h is connected to the connection port c. When an inspection section between the supply-side main plug 3 of the gas pipe 1 and the gas outlet 4 is inspected by the leak inspection apparatus A ', the connection port a is connected to the gas outlet 4 via a connection hose i or the like. , The supply-side main plug 3 is closed, the extraction-side main plug 5 of the gas extraction port 4 to which the leak inspection device A 'is connected is opened, the on-off valve d is closed, the on-off valve e is opened, and air is operated by operating the pressurizing pump h. The section to be inspected of the gas pipe 1 is filled by pressurization and pressurized to a predetermined pressure. Thereafter, the on-off valve d is opened and the on-off valve e is closed, and the pressure change is monitored by the pressure gauge g to confirm the presence or absence of leakage. When it is confirmed that there is no leakage of the gas pipe 1, the leak inspection device A 'is removed, the air filled in the gas pipe 1 is purged and replaced with fuel gas, and the take-out side main plug 5 is closed.
[0005]
In the above conventional example, the leak inspection device A 'is connected indoors to the gas outlet 4 to perform a leak inspection from indoors. However, there is also a method of connecting the leak inspection device A' outdoors to perform a leak inspection. In this case, the gas meter 2 is removed, the connection port a of the leak inspection device A 'is connected to the outlet side connection port 7 connected to the outlet of the gas meter 2, and air is pressurized by the pressurizing pump h in the same manner as described above. The gas pipe 1 is press-fitted into an inspection section, and a leak inspection is performed in the same manner as described above (for example, see Patent Document 1).
[0006]
FIG. 10 shows another example of the conventional leak inspection. The leak inspection apparatus A ″ of this example is provided with a pressurizing cylinder j instead of the pressurizing pump of the leak inspection apparatus A ′, and pressurizes a gas of the same type as the fuel gas supplied indoors to the pressurizing cylinder j. When an inspection section between the supply side main plug 3 of the gas pipe 1 and the gas outlet 4 is inspected by the leak inspection apparatus A ″, the connection port a is connected to the gas through the connection hose i or the like. It is connected to the outlet 4, closes the supply side main plug 3, opens the outlet side main plug 5 of the gas outlet 4 connected to the leak inspection device A ″, and fills the inspection section of the gas pipe 1 with the fuel gas from the pressurizing cylinder j. Then, the pressure change is monitored by a pressure gauge g to confirm the presence or absence of leakage, and after confirming that there is no leakage, the leakage inspection device A ″ is removed and the main plug 5 for taking out is closed ( (For example, see Patent Document 2)
[0007]
[Patent Document 1]
JP 2000-337942 A
[Patent Document 2]
JP-A-10-185751
[0008]
[Problems to be solved by the invention]
By the way, in the conventional example shown in FIG. 9 described above, it is necessary to enter the room and connect the leak inspection device A ′ to the indoor gas outlet 4 for inspection, and the inspection cannot be performed unless the inspector enters the room. For this reason, when the indoor space where the gas outlet 4 is located is a dwelling unit, it is necessary to put an inspector in the dwelling unit for inspection, and the residents may feel discomfort such as seeing a private place. . Further, since the inspection section of the gas pipe 1 is pressurized and filled with air for inspection, after the inspection is completed, it is necessary to purge the air of the gas pipe 1 and replace it with the fuel gas to be supplied. There is such a problem.
[0009]
When the gas meter 2 is detached and a leak inspection device A 'is connected at the connection point of the gas meter 2 for inspection, the inspection can be performed without entering the room. Needs to be purged and replaced with the supplied fuel gas, and there is a problem that this operation is troublesome. Although it is not necessary to enter the room at the time of the leak inspection, there is a problem that it is necessary to enter the room when the air is purged and replaced with the fuel gas.
[0010]
Further, in the conventional example shown in Fig. 10 as well, there is a problem that the leak inspection device A "must be connected to the indoor gas outlet 4 for inspection, and the inspection cannot be performed unless the inspector enters the room. In the case of the example, since the fuel gas is filled from the pressurizing cylinder j to pressurize the test section of the gas pipe 1, it is not necessary to purge the air after the test and replace it with the fuel gas. Is a heavy pressurizing cylinder j because it has a pressurizing cylinder j (in practice, there is no capacity enough to pressurize with a commercially available spray can and the pressure is 10 liters or more and 0.1 Mpa or more). There is a problem that it is difficult to handle the leak inspection device A ″ and labor is required because the device must be carried.
[0011]
SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is possible to perform a leak test without entering the room, and furthermore, it is possible to eliminate a trouble of purging air after the test and replacing the fuel gas with a fuel gas. An object of the present invention is to provide an inspection method and a leakage inspection device used for the inspection method.
[0012]
[Means for Solving the Problems]
A gas pipe leakage inspection method according to the present invention for solving the above-mentioned problems is provided in a gas pipe 1 between a gas meter 2 and an end of a room when the gas pipe 1 is leaked. By filling fuel gas into the inspection section of the gas pipe 1 from the side connection port 7 at a pressure higher than the normal fuel gas supply pressure, and monitoring the pressure of the filled fuel gas from the outlet side connection port 7 side. It is characterized in that the presence or absence of fuel gas leakage is inspected.
[0013]
The fuel gas is filled from the outlet side connection port 7 outdoors where the gas meter 2 is installed as described above, and the pressure of the filled fuel gas is monitored at the outlet side connection port 7 side to check for leakage. Inspection can be performed from the two installation locations and can be performed without entering the room. In addition, since the gas pipe 1 is filled with fuel gas and inspected, there is no need to purge air and replace it with fuel gas after a leak inspection, and it is not necessary to go indoors for this operation.
[0014]
Further, in the above-described leak inspection method, the fuel gas is pressurized and sent from the inlet side connection port 8 of the gas pipe 1 connected to the gas inlet of the gas meter 2 into the inspection section of the gas pipe 1 via the outlet side connection port 7. It is also preferable that the fuel gas is charged at a pressure higher than the normal fuel gas supply pressure.
[0015]
In this case, the inspection is easy because the fuel gas supplied from the gas supply source is pressurized and filled to perform the inspection, so that it is not necessary to handle a heavy pressurizing cylinder as in the case of supplying the fuel gas from the pressurizing cylinder. Can be.
[0016]
The gas pipe leakage inspection apparatus A according to the present invention includes a pipe 9 disposed between an inlet port 8 of the gas pipe 1 connected to the inlet of the gas meter 2 and an outlet port 7 connected to the outlet of the gas meter 2. An inlet-side connected port 10 provided at one end of the pipe 9 and connected to the inlet-side connection port 8; and an outlet-side connected port provided at the other end of the pipe 9 and connected to the outlet-side connection port 7. A connection port 11, a pressurizing means 12 provided in the middle of the pipe 9 for pressurizing the fuel gas, and a communication port 11 arranged between the pressurization means 12 and the outlet-side connected port 11. Pressure monitoring means 13 for monitoring the pressure in the pipe 9 by way of pressure; pipe opening / closing means 14 provided in the pipe 9 between the pressurizing means 12 and the pressure monitoring means 13 for opening and closing the pipe 9; It is arranged between the passage opening / closing means 14 and the outlet-side connected port 11 so as to communicate with the conduit 9 to remove air in the conduit 9. A vent pipe 15 for venting, characterized by comprising a vent pipe on-off valve 16 for opening and closing the vent pipe 15 is disposed in vent pipe 15.
[0017]
When the inspection is performed by the leak inspection device A, the leak inspection device A is disposed at a portion where the gas meter 2 is removed, and the inlet-side connected port 10 is connected to the inlet-side connected port 8 of the gas pipe 1 and the outlet-side connected port. 11 is connected to the outlet side connection port 7 of the gas pipe 1, the pipe opening / closing means 14 is opened and the drain pipe opening / closing valve 16 is opened, and the fuel gas is supplied from the inlet side connection port 8 and the drain pipe 15 is connected to the pipe 9. The inside of the gas pipe 1 is purged and replaced with fuel gas, and the open / close valve 16 for the drain pipe is closed. The pipe opening / closing means 14 is closed in a state where the pressure is increased, and the pressure monitoring means 13 monitors the pressure for a predetermined time to check for the presence or absence of leakage. When the inspection is completed, the leak inspection device A is removed and the gas meter 2 is attached. As described above, since the leak inspection device A is attached to the place where the gas meter 2 is attached and inspected, the leak inspection can be performed outdoors and the inspection can be performed without entering the room. In addition, since the inspection section of the gas pipe 1 is filled with the fuel gas and inspected, there is no need to purge air after the inspection and replace it with the fuel gas, and it is not necessary to enter the room for this operation. Further, since the fuel gas supplied from the inlet side connection port 8 of the gas pipe 1 is filled by pressurizing by the pressurizing means 12, it is not necessary to handle a heavy pressurizing cylinder as in the case of supplying the fuel gas from the pressurizing cylinder. , Inspection is easy. Further, before the fuel gas is pressurized and filled in the inspection section of the gas pipe 1, the air in the pipe 9 of the leak inspection apparatus A is purged from the vent pipe 15 and replaced with the fuel gas. The adverse effect of air entering the air can be prevented.
[0018]
It is also preferable that the leak inspection apparatus A is characterized in that an outlet-side on-off valve 17 for opening and closing the pipe line 9 is disposed at the outlet-side connected port 11. In this case, the air can be prevented from flowing into the inspection section of the gas pipe 1 by closing the outlet-side on-off valve 17 when opening the on-off valve 16 for the drain pipe and purging the air in the pipe 9 by closing the outlet-side on-off valve 17. After that, by closing the drain pipe opening / closing valve 16 and opening the outlet side opening / closing valve 17, the fuel gas can be pressurized and filled into the inspection section of the gas pipe 1. Thereby, the adverse effect of air entering the inspection section of the gas pipe 1 can be further prevented.
[0019]
Further, in the above-mentioned leakage inspection apparatus, a vent regulating portion 18 that prevents gas from flowing at a pressure lower than a predetermined value and allows gas to flow at a pressure higher than a predetermined value is provided in the outlet-side connected port 11. It is also preferred. In this case, it is possible to prevent the air from flowing into the inspection section of the gas pipe 1 by the ventilation restricting part 18 when purging the air in the pipe line 9 by opening the drain pipe opening / closing valve 16. By closing the valve 16, the fuel gas is allowed to pass through the ventilation regulating portion 18, and the test section of the gas pipe 1 can be filled with the fuel gas under pressure. Thereby, the adverse effect of air entering the inspection section of the gas pipe 1 can be further prevented. Further, the valve does not need to be opened and closed as in the case where the outlet side opening / closing valve 17 is provided as described above, so that the handling is simplified.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
As shown in FIG. 1, the gas pipe 1 is piped from the supply source side (the main pipe of a gas company in the case of city gas, the cylinder of LP gas) to the end of a house such as a dwelling unit. Gas meter 2 is arranged. A supply side main plug 3 for opening and closing a pipe is mounted on the gas pipe 1 at a portion upstream of the gas meter 2, and a take-out side main plug 5 is mounted on a gas take-out port 4 at an end of the gas pipe 1 on the indoor side. is there. In a room, the gas pipe 1 is generally branched into a plurality of branches, a plurality of gas outlets 4 are provided, and an outlet side main plug 5 is provided at each gas outlet 4. A gas appliance 6 is connected to the gas outlet 4. At the inlet of the gas meter 2, the inlet connection port 8 of the gas pipe 1 is detachably connected with a cap nut or the like, and at the outlet of the gas meter 2, the outlet connection port 7 of the gas pipe 1 is detachable with a cap nut or the like. Connected to
[0021]
The leak inspection device A for the gas pipe 1 is configured as shown in FIG. 3, for example. An inlet-side connected port 10 is provided at one end of the pipe 9 through which gas can flow, and the inlet-side connected port 10 is detachably connected to the inlet-side connected port 8 of the gas pipe 1. An outlet-side connected port 11 is provided at the other end of the pipe 9, and the outlet-side connected port 11 is detachably attached to the outlet-side connected port 7 of the gas pipe 1. You can connect. A pressurizing means 12 is arranged in the middle of the pipe 9 so that the fluid in the pipe 9 can be sent under pressure. In the case of the present example, the pressurizing means 12 is formed by providing a check valve 21 on an elastic ball body 20 having a hollow inside, and pressurizes the fluid manually by repeating the gripping operation of the elastic ball body 20. It can be sent. In the case of this example, a double elastic ball body 20 is provided, and can be pressurized to a high pressure. The pipe 9 is provided with a pipe opening / closing means 14 for opening and closing the pipe 9, and this pipe opening / closing means 14 is a pipe opening / closing valve 14 a in this embodiment, and is connected to the outlet side by the pressurizing means 12. A pipe opening / closing valve 14 a is arranged in the pipe 9 on the side of the port 11. An outlet opening / closing valve 17 that opens and closes the pipe 9 is disposed at the position of the outlet port 11 of the pipe 9. Pressure monitoring means 13 is provided for monitoring the pressure in the conduit 9 so as to communicate with the conduit 9 between the conduit opening / closing valve 14a and the outlet-side opening / closing valve 17. The pressure monitoring means 13 can monitor the pressure electronically, for example, by what is called a digital manometer. In the case of this example, a pressure monitoring on-off valve 23 that opens and closes a communication pipe 22 that connects the pressure monitoring means 13 and the pipe 9 is arranged. At a position slightly closer to the pipe opening / closing valve 14a than the outlet side opening / closing valve 17, a bleed pipe 15 branched from the pipe 9 is branched, and the air in the pipe 9 can be purged by the bleed pipe 15. It has become. The draft pipe 15 is provided with a draft pipe opening / closing valve 16 for opening and closing the draft pipe 15.
[0022]
The leakage inspection of the gas pipe 1 is performed as follows using the leakage inspection device A configured as described above. In this example, a section between the outlet side connection port 7 of the gas pipe 1 and the take-out side main plug 5 is inspected. First, in the state shown in FIG. 1, the supply-side main plug 3 is closed to shut off the gas supply, and the gas meter 2 is detached by disconnecting the inlet-side connection port 8 and the outlet-side connection port 7. Next, the leak inspection device A is arranged at a position where the gas meter 2 is removed, and the inlet side connection port 10 of the leak inspection device A and the inlet side connection port 8 of the gas pipe 1 are connected, and the leak side of the leak inspection device A is connected. The port 11 to be connected and the outlet port 7 of the gas pipe 1 are connected, and a leak inspection device A is attached as shown in FIG. In this state, the pipeline open / close valve 14a and the pressure monitoring open / close valve 23 are open, and the outlet side open / close valve 17 and the drain pipe open / close valve 16 are closed. After attaching the leak inspection device A, the supply side main plug 3 is opened and the on-off valve 16 for the drainage pipe is opened. Then, the fuel gas is supplied from the inlet side connection port 8 into the pipe 9 at a normal gas supply pressure, and the air in the pipe 9 is purged from the vent pipe 15 to replace the air in the pipe 9 with the fuel gas. You. At this time, since the outlet side on-off valve 17 is closed, air is prevented from flowing into the inspection section of the gas pipe 1. When the air is purged from the bleed pipe 15, the bleed pipe on-off valve 16 is closed and the outlet side on-off valve 17 is opened. Then, the fuel gas is pressurized by the pressurizing means 12 to fill the inspection section of the gas pipe 1 with a predetermined pressure (a pressure sufficiently higher than a normal fuel gas supply pressure, for example, the gas supply pressure is usually 2 kPa. To 7 to 8 kPa). When the pressure is increased to the predetermined pressure, the supply-side main plug 3 and the pipeline opening / closing valve 14a are closed, and the pressure monitoring unit 13 monitors the pressure fluctuation for a predetermined time to confirm whether there is any leakage.
[0023]
When the inspection for the presence or absence of leakage is completed, the opening / closing valve 16 for the drain pipe is opened to reduce the pressure, and the outlet-side opening / closing valve 17 is closed. Next, the connection between the inlet-side connected port 10 of the leak inspection apparatus A and the inlet-side connection port 8 of the gas pipe 1 is disconnected, and the outlet-side connected port 11 of the leak inspection apparatus A and the outlet-side connection port 7 of the gas pipe 1 are connected. And disconnect the leak inspection device A. At this time, the inlet-side connection port 8 and the outlet-side connection port 7 are closed with a rubber stopper in order to prevent the inflow of air. Next, the gas meter 2 is attached as shown in FIG.
[0024]
The gas pipe 1 is inspected for leakage as described above. A leak inspection device A is attached to a place where the gas meter 2 is installed, and the fuel gas is pressurized and filled from this place, and the pressure is monitored at this place for leakage. The inspection can be performed without entering the interior of a dwelling unit or the like in order to perform the inspection. Further, it is not necessary to purge the air of the gas pipe 1 and replace it with fuel gas after the inspection, as in the case of filling the gas pipe 1 with air under pressure to perform the inspection. It is not necessary, and there is no need to enter the interior of a dwelling unit or the like to perform this operation. Further, since the combustion gas to be charged into the gas pipe 1 under pressure is supplied by pressurizing the fuel gas supplied from the upstream side of the gas meter 2 by the pressurizing means 12, a pressurizing cylinder or the like is required as in the prior art. And can be easily handled. Further, since air is purged from the vent pipe 15 and replaced with fuel gas before the gas pipe 1 is pressurized and filled with fuel gas, even if air is present in the pipe 9, air flows into the gas pipe 1. Can be prevented.
[0025]
In the above example, the communication pipe 22 is connected to the pipe 9 between the drain pipe 15 and the pipe opening / closing valve 14a, and the pressure monitoring means 13 monitors the pressure. If the drain pipe on-off valve 16 is detachably connected to the drain pipe opening / closing valve 16, it is not necessary to connect the communication pipe 22 so as to branch off between the drain pipe 15 and the pipeline open / close valve 14 a, and a portion where the drain pipe 15 branches off Can be used to monitor pressure. That is, after the air is purged from the drain pipe 15, the pressure monitoring unit 13 can monitor the pressure by connecting the communication pipe 22 to the drain pipe opening / closing valve 16. By doing so, the pipe structure can be simplified, and the number of parts can be reduced by also using the on-off valve.
[0026]
FIG. 4 shows another example of the leakage inspection device A. This embodiment is basically the same as the above embodiment, but differs from the above embodiment in the pressurizing means 12. In the case of this example, a cylinder-type manual pump, which is a cylinder 25 communicating with the pipe 9, a piston 26 slidably disposed in the cylinder 25, an operation rod 27 for reciprocating the piston 26, and a cylinder 25 And a check valve 28 provided on the inflow side and the outflow side.
[0027]
The pipe opening / closing means 14 is provided for the purpose of holding the pressure of the pipe 9. The check valve 28 for preventing backflow of the pressurizing means 12 and the like are provided with a pipe opening / closing means for holding the pressure of the pipe 9. If the function of 14 is performed, the check valve 28 and the like can be used as the conduit opening / closing means 14. Therefore, there is no need to separately provide the pipeline opening / closing means 14 such as the pipeline opening / closing valve 14a as in the above example, and such an opening / closing means can be omitted. However, in this case, the pressurizing means 12 may be deformed by the pressure or the driving part may move, and as a result, the pressure may fluctuate. In some cases, a means for preventing the above-mentioned pressure fluctuation (for example, a stopper for a manual part) may be required. In the case of the example shown in FIG. 4, the pressure fluctuation can be prevented by providing a stopper for fixing the operation rod 27, the check valve 28 can also be used as the pipe opening / closing means 14, and the pipe opening / closing means 14 needs to be provided separately. There is no.
[0028]
FIG. 5 shows another example of the leakage inspection device A. This embodiment is basically the same as the above embodiment, except that an air flow restricting portion 18 is provided instead of the outlet side on-off valve 17 of the above embodiment. The ventilation restricting portion 18 prevents the gas from flowing at a pressure lower than a predetermined value and restricts the gas flow so that the gas flows at a pressure higher than the predetermined value. That is, when the vent pipe opening / closing valve 16 is opened to purge the air in the conduit 9 from the vent pipe 15, only a predetermined pressure or less is applied to the vent regulating section 18 and air is not ventilated to the vent regulating section 18. When the pressurized fuel gas is sent by closing the pipe opening / closing valve 16, the fuel gas passes through the ventilation regulating section 18 and the gas pipe 1 is filled with the fuel gas. Therefore, when the on-off valve 16 for the drain pipe is opened to purge the air in the pipe line 9, it is possible to prevent air from flowing into the inspection section of the gas pipe 1 by the ventilation restricting section 18, whereby air is introduced into the inspection section of the gas pipe 1. It is possible to further prevent adverse effects. Further, the valve does not need to be opened and closed as in the case where the outlet side opening / closing valve 17 is provided as described above, so that the handling is simplified.
[0029]
As shown in FIG. 7, even if the ventilation restricting portion 18 is configured such that the two plate-shaped members 30 are overlapped with a slight gap therebetween so as to close the passage as shown in FIGS. 6 (a) and 6 (b). It may be formed of a porous material 31 or may be formed of a tubular aggregate 32 as shown in FIGS.
[0030]
In the example of the above-described embodiment, an example has been described in which the fuel gas is supplied from the inlet-side connection port 8 of the gas pipe 1 and pressurized and filled into the inspection section. The inspection according to the present invention can be performed even when fuel gas is supplied to the inspection section via the outlet-side connection port 7. In this case, the leak inspection apparatus A does not require the pressurizing means 12, but it is necessary to carry a heavy pressurizing cylinder.
[0031]
【The invention's effect】
According to the first aspect of the present invention, when inspecting a leak of a gas pipe between a gas meter and a terminal inside a room, the fuel is injected into an inspection section of the gas pipe from an outlet side connection port of the gas pipe connected to an outlet of the gas meter. The gas is charged at a higher pressure than the normal fuel gas supply pressure, and the pressure of the charged fuel gas is monitored from the outlet connection port side to check for leakage of the fuel gas. It can be inspected without entering the room because it can be inspected for leaks.Furthermore, since the gas pipe is filled with fuel gas and inspected, there is no need to purge air after the leak inspection and replace it with fuel gas. There is no need to go indoors to do
[0032]
According to a second aspect of the present invention, in the first aspect, the fuel gas is introduced into the inspection section of the gas pipe from the inlet side connection port of the gas pipe connected to the gas inlet of the gas meter via the outlet side connection port. Since the fuel gas is charged at a pressure higher than the normal fuel gas supply pressure by sending it under pressure, the fuel gas supplied from the gas supply source is pressurized and charged to fill the fuel gas from the pressurizing cylinder for inspection. The inspection can be easily performed without requiring the handling of a heavy pressurizing cylinder unlike that supplied.
[0033]
The invention according to claim 3 of the present invention is characterized in that a pipe disposed between an inlet-side connection port of a gas pipe connected to an inlet of a gas meter and an outlet-side connection port connected to an outlet of the gas meter, and one end of the pipe. An inlet-side connected port that can be provided and connected to the inlet-side connected port, an outlet-side connected port that is provided at the other end of the pipe and that can be connected to the outlet-side connected port, and that is provided in the middle of the pipe. Pressurizing means for pressurizing the fuel gas, pressure monitoring means arranged to communicate with the conduit between the pressurizing means and the outlet-side connected port, and monitoring pressure in the conduit, and pressurizing means. A pipe opening / closing means provided in the pipe between the pressure monitoring means to open and close the pipe; and a pipe arranged between the pipe opening / closing means and the outlet-side connected port so as to communicate with the pipe. Leakage provided with a drain pipe for discharging air inside the drain pipe, and a drain pipe opening / closing valve arranged in the drain pipe to open and close the drain pipe Since it is an inspection device, a leak inspection device is arranged at the part where the gas meter is removed, the inlet side connected port is connected to the inlet side connection port of the gas pipe, and the outlet side connected port is connected to the outlet side connection port of the gas pipe. Connect, open the pipe opening / closing means, open the drain pipe opening / closing valve, supply fuel gas from the inlet side connection port, purge the air in the pipe from the drain pipe, and replace the fuel gas with the fuel gas. Is closed and pressurized by the pressurizing means to fill the test section of the gas pipe with the pressurized fuel gas, the test section is pressurized to a predetermined pressure, the pipe opening / closing means is closed, and the pressure monitoring It is capable of monitoring the time pressure and checking for the presence or absence of leakage, and it is possible to perform a leak test outdoors to mount and check the leak test device at the place where the gas meter is mounted as described above. Entering indoors In addition, it is possible to perform the inspection without filling the inspection section of the gas pipe with the fuel gas and inspecting it by purging air after the inspection and replacing it with the fuel gas. It is not necessary to enter indoors, and the fuel gas supplied from the inlet side connection port of the gas pipe is pressurized and filled by the pressurizing means, so that it is heavy like a fuel gas is supplied from a pressurizing cylinder. It does not require the handling of pressurized cylinders and can be easily inspected.Furthermore, before filling the test section of the gas pipe with fuel gas by pressurizing it, the air in the pipe of the leak inspection device must be vented from the pipe. Since the fuel gas is purged and replaced with the fuel gas, it is possible to further prevent the problem that air enters the inspection section of the gas pipe.
[0034]
According to a fourth aspect of the present invention, in the third aspect, the outlet side on-off valve for opening and closing the pipe is disposed at the outlet side connected port, so that the drainage pipe on-off valve is opened to purge air from the pipe. By closing the outlet side on-off valve, air can be prevented from flowing into the inspection section of the gas pipe, and after purging air, the fuel gas is released by closing the drain pipe on-off valve and opening the outlet side on-off valve. The inspection section of the pipe can be filled under pressure, and the adverse effect of air entering the inspection section of the gas pipe can be further prevented.
[0035]
According to a fifth aspect of the present invention, in the third aspect, a ventilation restricting portion is provided at the outlet-side connected port to prevent gas from flowing at a pressure lower than a predetermined value and to allow gas to flow at a pressure higher than a predetermined value. Therefore, it is possible to prevent air from flowing into the inspection section of the gas pipe at the ventilation control section when purging air in the pipeline by opening the on-off valve for the drain pipe and closing the on-off valve for the drain pipe after purging the air. The fuel gas can be passed through the ventilation control section to fill the test section of the gas pipe with the fuel gas under pressure, whereby the adverse effect of air entering the test section of the gas pipe can be further prevented. Unlike the one provided with the outlet-side on-off valve of the fourth aspect, the valve does not need to be opened and closed and the handling is simplified.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining an example of an embodiment of the present invention and is a pipeline diagram of a gas pipe.
FIG. 2 is a partially exploded pipeline diagram illustrating a state to be inspected according to the first embodiment.
FIG. 3 is a front view showing the leakage inspection device of the above.
FIG. 4 is a front view showing another example of the leakage inspection device of the above.
FIG. 5 is a front view showing another example of the leakage inspection device of the above.
FIGS. 6A and 6B show an example of the airflow restricting portion of the above, and FIG. 6A is a perspective view and FIG. 6B is a sectional view.
FIG. 7 is a perspective view showing another example of the ventilation restricting unit according to the third embodiment.
FIGS. 8A and 8B show another example of the ventilation restricting unit according to the embodiment, wherein FIG. 8A is a perspective view and FIG. 8B is an enlarged view of a main part of FIG.
9 (a) is a pipe diagram of a conventional example in a state to be inspected, FIG. 9 (b) is a partially cutaway front view enlarging an X section of FIG. 9 (a), and FIG. 9 (c) is a Y section of FIG. It is a partially cutaway front view which can be expanded.
FIG. 10 is a pipeline diagram illustrating a state of another conventional inspection.
[Explanation of symbols]
A Leakage inspection device
1 Gas piping
2 Gas meter
7 Exit side connection port
8 Entrance side connection port
9 pipeline
10 Entrance-side connected port
11 Exit side connected port
12 Pressurizing means
13 Pressure monitoring means
14 Pipe opening and closing means
14a Pipe open / close valve
15 Draft tube
16 Open / close valve for drain pipe
17 Exit-side on-off valve
18 Ventilation control section

Claims

When inspecting the gas pipe for leaks between the gas meter and the indoor end, the fuel gas is supplied from the outlet side of the gas pipe connected to the outlet of the gas meter into the gas pipe inspection section within the gas pipe inspection section. A gas pipe leakage inspection method, characterized in that the fuel gas is filled at a high pressure and the pressure of the filled fuel gas is monitored from an outlet side connection port to check for a fuel gas leak.

Higher than normal fuel gas supply pressure by pressurizing and sending fuel gas from the inlet side connection port of the gas pipe connected to the gas inlet of the gas meter into the inspection section of the gas pipe via the outlet side connection port. 2. The gas pipe leakage inspection method according to claim 1, wherein the gas pipe is filled with pressure.

A pipe disposed between an inlet-side connection port of a gas pipe connected to an inlet of the gas meter and an outlet-side connection port connected to an outlet of the gas meter; and a pipe provided at one end of the pipe and connected to the inlet-side connection port. An inlet-side connected port, an outlet-side connected port that is provided at the other end of the pipe and can be connected to the outlet-side connected port, and a pressurizing means that is provided in the middle of the pipe and pressurizes the fuel gas; A pressure monitoring means arranged to communicate with the pipeline between the pressure means and the outlet-side connected port and monitoring the pressure in the pipeline; and a pressure monitoring means provided in the pipeline between the pressure means and the pressure monitoring means. Pipe opening / closing means for opening / closing a pipe, and a drain pipe arranged to communicate with the pipe between the pipe opening / closing means and the outlet-side connected port, for removing air in the pipe to the outside. And a leak valve for a gas pipe, which is provided on the drain pipe and opens and closes the drain pipe to open and close the drain pipe. Location.

4. The gas pipe leakage inspection device according to claim 3, wherein an outlet-side on-off valve for opening and closing the pipe line is disposed at the outlet-side connected port.

4. Leakage of a gas pipe according to claim 3, wherein a gas flow restricting portion for preventing gas from flowing at a pressure lower than a predetermined level and flowing gas at a pressure higher than a predetermined level is provided at the outlet-side connected port. Inspection equipment.