JP2004181503A

JP2004181503A - Method for manufacturing elbow for air supply and discharge pipe, the elbow, and jig and tool

Info

Publication number: JP2004181503A
Application number: JP2002353382A
Authority: JP
Inventors: Kunio Kawasaki; 邦夫河▲崎▼
Original assignee: NISSEI TECHNOS KK
Current assignee: NISSEI TECHNOS KK
Priority date: 2002-12-05
Filing date: 2002-12-05
Publication date: 2004-07-02

Abstract

<P>PROBLEM TO BE SOLVED: To provide a triple elbow for air supply/discharge pipes required to realize a triple air supply/discharge pipe of a boiler or the like, a manufacturing method therefor, and a jig and tool used in the manufacturing method. <P>SOLUTION: The elbow for air supply/discharge pipes is manufactured by using two jigs and tools 7 and 8 having three fit-in cylinders fixed in a concentrically telescopic manner in section so as to be fitted in a large diameter cylinder 2, a medium diameter cylinder 3, and a small diameter cylinder 4, respectively, and a handle fixed to three fit-in cylinders, inserting and fitting one of the jigs and tools 7 and 8 to one end side of a triple pipe 6 for air supply/discharge pipes, inserting and fitting the other jig and tool to the other end side of the triple pipe 6 for air supply/discharge pipes, fixing the jig and tool 8 to a predetermined place, and turning the jig and tool 7 and bending the triple pipe for air supply/discharge pipes at a predetermined angle in a bellows W. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、ボイラの給排気筒の配管材として使用される給排気筒用エルボとその製造方法、並びにその製造方法に用いる治工具に関する。
【０００２】
【従来の技術】
灯油、天然ガス等を燃焼させて高温水、蒸気等を発生するボイラの給排気筒としては、２重管が採用されることが多い（例えば、特許文献１）。図５に示すように、２重管１１は、小径管１１ａが大径管１１ｂの中に配置されたものであり、そのコーナ部においては、２重管のエルボ（以下「２重の給排気筒用エルボ」という。）１４が使用される。小径管１１ａの内径側は、ボイラ１２によって熱された高温空気の排気路として使用され、小径管１１ａの外径側と大径管１１ｂの内径側の管路は、外気の給気路として使用される。２重管１１は、外観的に１本の管なので、配管工事に際して壁面１３に明ける貫通穴は１つで済み、施工の簡略化を図ることができる等の利点がある。
【０００３】
【特許文献１】
特開平９−２５７３１２号公報（段落番号００１１、第２図）
【０００４】
【発明が解決しようとする課題】
２重管１１を通じてボイラ１２に給入される外気は、ボイラ１２が外気温を想定して設計されていることから、想定した温度範囲を超える空気の給入は燃焼効率の低減を招くため好ましくない。しかし、２重管１１では、小径管１１ａと大径管１１ｂの間を通って給入される外気は、小径管１１ａを伝って放熱される排気熱の影響を受けて昇温され易いため、ボイラ１２の燃焼効率の悪化やボイラ１２の寿命短縮化を招くという問題がある。
【０００５】
一方、相互に異径の３つの小径管、中径管及び大径管が入れ子状に配置された３重管を使用し、小径管内を排気用管路、中径管と大径管の間を給気用管路とするとともに、小径管と中径管の間の空隙を排気用管路と給気用管路の間の断熱層として使用すれば、上記問題は解決すると本件発明者は考えた。
【０００６】
ところが、３重管のコーナ部に使用する３重の給排気筒用エルボは製作が困難であることから、３重管を使用した配管構造を採用ことができなかった。すなわち、２重の給排気筒用エルボ１４を製作するにあったっては、中間部に蛇腹が設けられた相互に異径の薄肉円筒を断面同芯円の入れ子状に配置して、その一端側を横架金具１４ｄにて相互に溶接固定した後、薄肉円筒の両端部を掴んで蛇腹１４ａで所定角に屈曲させることで簡単に製作することができ、仮に小径管１４ｂと大径管１４ｃが多少偏芯したり変形したりしても容易に修正することができる。これに対し、３重の給排気筒用エルボの場合は、給気及び排気効率をある程度確保すると同時に十分な断熱効果を得るため、小径管と中径管の間の空隙厚さを厚くなり過ぎないように管径を設定し、なお且つ、その空隙厚さが周面に沿って均等になるように各管同士を配置することが必要である。したがって、上記したように３重の給排気筒の両端部を掴んで屈曲加工を施すだけでは、小径配管と中径配管の軸心が相互に偏芯して一部で接触したり、両端部で管の端口部の円形状が楕円に変形したりするため、結局周面に沿って均一となった空隙厚さを確保することが困難であった。また、屈曲加工後に各管の軸芯や変形を修正加工しょうとしても、３重の給排気筒用エルボの場合は、各管の修正加工は、その他の２本の管との相対位置関係に基づいて行う必要があるため、２重の給排気筒用エルボの場合のように容易に行うことはできなかった。
【０００７】
本発明は、かかる課題に鑑みてなされたものであり、ボイラ等の給排気筒を３重管方式とするために必要な３重の給排気筒用エルボを提供するとともに、その製造方法とその製造方法において使用する治工具を提供することを目的とする。
【０００８】
【課題を解決するための手段】
上記目的を達成するために、請求項１記載の給排気筒用エルボの製造方法は、中間部に蛇腹が設けられた相互に異径の薄肉円筒からなる大径円筒、中径円筒及び小径円筒が断面同芯円の入れ子状に配置され、一端側同士が相互に横架金具によって固定された給排気筒用３重管を所定角度に屈曲する給排気筒用エルボの製造方法であって、前記大径円筒、中径円筒及び小径円筒のそれぞれに嵌め込まれるように断面同芯円の入れ子状に配置されて固定された３つの嵌込み円筒と、該３つの嵌込み円筒に固定されたハンドルとを備える治工具を２つ用い、前記治工具の一方を前記給排気筒用３重管の一端側に挿入嵌合し、前記治工具の他方を前記給排気筒用３重管の他端側に挿入嵌合し、前記給排気筒用３重管の両端側に挿入嵌合された何れか一方の前記治工具を所定場所に固定し、何れか他方の前記治工具を回転させることにより、前記給排気筒用３重管を前記蛇腹において所定の角度に屈曲させることを特徴としている。
【０００９】
請求項２記載の給排気筒用エルボは、中間部に蛇腹が設けられた相互に異径の薄肉円筒からなる大径円筒、中径円筒及び小径円筒が断面同芯円の入れ子状に配置され、一端側同士が相互に横架金具によって固定された給排気筒用３重管が前記蛇腹において所定の角度に屈曲されてなることを特徴としている。
【００１０】
請求項３記載の治工具は、断面同芯円状の入れ子状に配置された、相互に異径の薄肉円筒からなる大径円筒、中径円筒及び小径円筒の一端側のそれぞれに嵌め込まれるように断面同芯円の入れ子状に配置されて固定された３つの嵌込み円筒と、該３つの嵌込み円筒に固定されたハンドルと、を備えることを特徴としている。
【００１１】
【発明の実施の形態】
以下、本発明の実施の形態に係る給排気筒用エルボ及びその製造方法、並びにその製造方法に使用する治工具について図面に基づき説明する。
【００１２】
図１及び２に示すように、給排気筒用エルボ１は、中間部に蛇腹Ｗが設けられた相互に異径の薄肉円筒からなる大径円筒２、中径円筒３及び小径円筒４が断面同芯円の入れ子状に配置され、一端側同士が相互に横架金具５によって溶接固定された給排気筒用３重管が蛇腹Ｗにおいて所定の角度に屈曲加工されてなるものである。
【００１３】
前記給排気筒用エルボ１を製造する場合、まず、図３に示すように、中間部に蛇腹Ｗが設けられた相互に異径の薄肉円筒からなる大径円筒２、中径円筒３及び小径円筒４を用意し、これら円筒２、３、４を同芯円の入れ子状に配置して、横架金具５にて小径円筒４と中径円筒３の一端側同士、及び中径円筒３と大径円筒２の同じ一端側同士を、内又は外周面に沿って等間隔に３個所以上溶接固定する。横架金具５としては、薄板が断面略ひの字状に折曲加工されてなるものが使用されているが、円筒同士を相互に上記状態で固定できるものであれば、図示形状に限定されない。しかし、管路の空気通過面積をできるだけ多く確保するためには、図示するように、板面を流路（配管の長手方向）に沿って配置した薄板状のものを使用することが好ましい。なお、前記蛇腹Ｗは、薄肉円筒２、３、４の屈曲を容易にするために設けられている。
【００１４】
小径円筒４と中径円筒３との隙間は、中径円筒３と大径円筒２との隙間と比較して小さく設けられており、給気及び排気管路の断面積が多く確保されるような構造となっている。また、図示形状においては、大径円筒２と小径円筒４は、ほぼ同じ長さを有し、中径円筒３はこれら円筒２、４より少し短くなっているが、各円筒２、３、４の長さは、接続される相手配管との関係定まるものであり、この長さ関係に限定されない。例えば、これら円筒２、３、４の長さが全て同一である場合や中径円筒３が他の円筒２、４より長く突出していてもよい。なお、小径円筒４の一端部は先端側へ縮径した雄継手４ａであり、また、大径円筒２の他端部も先端側へ縮径した雄継ぎ手２ａであり、相手配管に嵌入される雄継手となっている（以下小径円筒４に雄側継手が形成されている方を「雄側」、その反対側を「雌側」という。）。
【００１５】
次に、図４（ａ）に示すように、給排気筒用３重管６の雄側に第１の治工具７を、その雌側に第２の治工具８をそれぞれ挿入嵌合する。ここで、第１の治工具７は、給排気筒用３重管６の雄側の大径円筒２、中径円筒３及び小径円筒４のそれぞれに嵌め込まれるように断面同心円の入れ子状に配置された３つの嵌込み円筒７ａ、７ｂ、７ｃと、これら嵌込み円筒の端部を相互に固定する嵌込み円筒固定板７ｄと、該嵌込み円筒固定板７ｄを介して３つの嵌込み円筒７ａ、７ｂ、７ｃに一端側が固定された棒鋼からなる第１ハンドル７ｅと、を備えるものである。３つの嵌込み円筒７ａ、７ｂ、７ｃは、給排気筒用３重管６の雄側の大径円筒２、中径円筒３及び小径円筒４の外周面に沿ってそれぞれ嵌め込まれる構造となっているが、中径円筒３、大径円筒４に対しては、小径円筒４のように前記雄側継手形状が設けられていないことから、嵌込み円筒７ａ、７ｂを大径円筒２、中径円筒３の内周面に沿ってそれぞれ嵌め込まれるような構造としてもよい。なお、３つの嵌込み円筒のうち最も内径側に配置された嵌込み円筒７ｃは、他の嵌込み円筒７ａ、７ｂより管長さが短くなっているが、これは、給排気筒用３重管６の雄側に設けられた前記横架金具５との干渉を避けるためであり、横架金具５の有無や横架金具５の取り付け位置に対応してその長さは決められる。
【００１６】
一方、前記第２の治工具８は、給排気筒用３重管６の雌側の大径円筒２、中径円筒３及び小径円筒４のそれぞれに嵌め込まれるように断面同心円の入れ子状に配置された３つの嵌込み円筒８ａ、８ｂ、８ｃと、これら嵌込み円筒の端部を相互に固定する嵌込み円筒固定板８ｄと、該嵌込み円筒固定板８ｄを介して３つの嵌込み円筒８ａ、８ｂ、８ｃに一端が固定された所定長さの角鋼材等からなる第２ハンドル８ｅと、を備えるものである。３つの嵌込み円筒８ａ、８ｂ、８ｃのうち最も内径側にある嵌込み円筒８ｃは、給排気筒用３重管６の雌側の小径円筒４の内周面に沿って嵌め込まれ、その他の嵌込み円筒８ａ、８ｂは、給排気筒用３重管６の雌側の大径円筒２、中径円筒３の外周面に沿ってそれぞれ嵌め込まれる構造となっている。なお、中径円筒３、小径円筒４に対しては、大径円筒２のように前記雄側継手形状が設けられていないことから、中間にある嵌込み円筒８ｂを中径円筒３の内周面に沿って、内径側にある嵌込み円筒８ｃを小径円筒４の外周面に沿ってそれぞれ嵌め込まれるような構造としてもよい。また、３つの嵌込み円筒８ａ、８ｂ、８ｃは、内径側の円筒ほど管長さが若干短くなっている。このため、嵌込み円筒８ａ、８ｃと給排気筒用３重管６の雌側の大径円筒２、小径円筒４との嵌まり込み位置が前後し、嵌め込み作業の容易化が図られる。
【００１７】
上記した図４（ａ）に示す状態、つまり、第１の治工具７及び第２の治工具８が給排気筒用３重管６の両側にそれぞれ挿入された状態から、第２の治工具８の角鋼材からなる第２のハンドル８ｅを作業台９の凹部９ａに嵌挿して作業台９上に固定する。そして、図４（ｂ）に示すように、第１の治工具７の第１のハンドル７ｅを握って作業台９側へ所定角度（９０°、４５°等）回転させることにより、給排気筒用３重管６を蛇腹Ｗにおいて所定角度に屈曲させる。屈曲加工に際しては、第１及び第２の治工具７、８の嵌込み円筒７ａ、７ｂ、７ｃ、８ａ８ｂ、８ｃはそれぞれ、給排気筒用３重管６の円筒２乃至４の両端部の周面にそれぞれピッタリと嵌合した状態で行われるため、上記工程を経て製造される給排気筒用エルボ１の両端部は、偏芯したり楕円状に変形したりすることなく、同芯円状態が維持される。また、中径円筒３と小径円筒４の隙間が小さくても、これら円筒３、４は互いに均等に曲げられることから、一部において相互に接触したり偏芯するようなことはない。
【００１８】
【発明の効果】
請求項１記載の給排気筒用エルボの製造方法によれば、給排気筒用３重管の屈曲加工は、治工具の嵌込み円筒がそれぞれ、給排気筒用３重管の両端部の周面に沿ってそれぞれピッタリと嵌合した状態で行われるため、給排気筒用３重管は、偏芯したり楕円状に変形することなく、同芯及び真円形状が保持されたまま屈曲加工を行うことができる。また、給排気筒用エルボの中径円筒と小径円筒の間の隙間が少ないような場合でも、これら円筒同士の間の隙間は、周面に沿って均一に保持されるので、給気管路と排気管路の断熱を十分に確保しつつ、管路内での圧力損失が低く抑えられた給排気筒用エルボを製造することができる。
【００１９】
請求項２記載の給排気筒用エルボがあれば、ボイラ等の給排気管として、３重の給排気配管を採用することが可能となり、ボイラの燃焼効率の向上、ボイラの耐久性の向上が可能となる。
【００２０】
請求項３記載の治工具によれば、請求項１記載の給排気筒用エルボの製造方法を実現することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係る給排気筒用エルボの縦断面図である。
【図２】図１のＡ−Ａ矢視図である。
【図３】給排気筒用３重管の縦断面図である。
【図４】本発明の実施の形態に係る給排気筒用エルボの製造手順を示した説明図である。
【図５】従来例に係る２重の給排気筒用エルボの部分断面説明図である。
【符号の説明】
Ｗ蛇腹
１給排気筒用エルボ
２大径円筒
３中径円筒
４小径円筒
５横架金具
６給排気筒用３重管
７（第１の）治工具
７ａ乃至７ｃ嵌込み円筒
７ｅ（第１の）ハンドル
８（第２の）治工具
８ａ乃至８ｃ嵌込み円筒
８ｅ（第２の）ハンドル[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a supply / exhaust tube elbow used as a piping material of a supply / exhaust tube of a boiler, a method of manufacturing the same, and a jig used for the method of manufacturing the elbow.
[0002]
[Prior art]
A double pipe is often used as a supply / exhaust pipe of a boiler that generates high-temperature water, steam, and the like by burning kerosene, natural gas, and the like (for example, Patent Document 1). As shown in FIG. 5, the double pipe 11 has a small-diameter pipe 11a disposed inside a large-diameter pipe 11b, and has a double-pipe elbow (hereinafter referred to as "double supply / discharge") at a corner thereof. A cylinder elbow is used.) 14 is used. The inner diameter side of the small-diameter pipe 11a is used as an exhaust path for high-temperature air heated by the boiler 12, and the outer-diameter side of the small-diameter pipe 11a and the inner-diameter side of the large-diameter pipe 11b are used as external air supply paths. Is done. Since the double tube 11 is a single tube in appearance, only one through hole is required to be drilled in the wall surface 13 at the time of piping work, and there is an advantage that the construction can be simplified.
[0003]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 9-25712 (paragraph number 0011, FIG. 2)
[0004]
[Problems to be solved by the invention]
The outside air supplied to the boiler 12 through the double pipe 11 is preferable because the boiler 12 is designed in consideration of the outside air temperature, so that the supply of air exceeding the assumed temperature range causes reduction in combustion efficiency. Absent. However, in the double pipe 11, the outside air supplied through the space between the small-diameter pipe 11a and the large-diameter pipe 11b is likely to be heated by the influence of the exhaust heat radiated along the small-diameter pipe 11a. There is a problem that the combustion efficiency of the boiler 12 is deteriorated and the life of the boiler 12 is shortened.
[0005]
On the other hand, a triple pipe in which three small-diameter pipes, medium-diameter pipes, and large-diameter pipes having mutually different diameters are nested is used. If the air supply line is used as the air supply line and the gap between the small-diameter pipe and the medium-diameter pipe is used as a heat insulating layer between the exhaust pipe and the air supply pipe, the inventor of the present invention solves the above problem. Thought.
[0006]
However, since it is difficult to manufacture a triple supply / exhaust tube elbow used in a corner portion of a triple tube, a piping structure using a triple tube cannot be adopted. That is, when manufacturing the double elbow 14 for the supply / exhaust cylinder, thin cylinders having mutually different diameters provided with bellows in the middle portion are arranged in a nested shape having a concentric circular section, and one end thereof is provided. Can be easily manufactured by fixing both ends of the thin-walled cylinder and bending the bellows to a predetermined angle with the bellows 14a, and the small-diameter pipe 14b and the large-diameter pipe 14c are temporarily fixed. Even if it is slightly eccentric or deformed, it can be easily corrected. On the other hand, in the case of a triple supply / exhaust cylinder elbow, the thickness of the gap between the small-diameter pipe and the medium-diameter pipe becomes too thick in order to secure air supply and exhaust efficiency to some extent and to obtain a sufficient heat insulating effect. It is necessary to set the pipe diameters so that there is no gap, and to arrange the pipes so that the gap thickness becomes uniform along the peripheral surface. Therefore, as described above, simply grasping both ends of the triple supply / exhaust cylinder and performing bending processing causes the axes of the small-diameter pipe and the medium-diameter pipe to be eccentric to each other and partially contact each other, As a result, the circular shape of the end portion of the pipe may be deformed into an ellipse, so that it was difficult to secure a uniform gap thickness along the peripheral surface. Also, even if it is attempted to correct the axis or deformation of each pipe after bending, in the case of a triple supply / exhaust cylinder elbow, the correction processing of each pipe depends on the relative positional relationship with the other two pipes. Therefore, it was not possible to perform this easily as in the case of a double supply / exhaust cylinder elbow.
[0007]
The present invention has been made in view of the above problems, and provides a triple supply / exhaust cylinder elbow required for using a triple pipe system for a supply / exhaust cylinder of a boiler or the like, a method of manufacturing the elbow, and a method of manufacturing the same. It is an object of the present invention to provide a tool used in a manufacturing method.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a method for manufacturing an elbow for a supply / exhaust cylinder according to claim 1, wherein the large-diameter cylinder, the medium-diameter cylinder, and the small-diameter cylinder are formed of thin-walled cylinders having different diameters provided with bellows at an intermediate portion. Are arranged in a nested shape of concentric circles in cross section, and a method for manufacturing an elbow for a supply / exhaust cylinder in which a triple pipe for an intake / exhaust cylinder whose one end sides are mutually fixed by a horizontal bracket is bent at a predetermined angle, Three fitting cylinders arranged and fixed in a nested shape having concentric cross sections so as to be fitted into the large-diameter cylinder, the medium-diameter cylinder and the small-diameter cylinder, respectively, and a handle fixed to the three fitting cylinders And one of the jigs is inserted and fitted into one end of the triple pipe for the supply / exhaust cylinder, and the other end of the triple pipe for the supply / exhaust cylinder is connected to the other end of the triple pipe for the supply / exhaust cylinder. One of the three pipes for the air supply / exhaust cylinder, The jig is fixed to a predetermined location, by rotating the other one of said tools is characterized by bending the triple pipe the supply stack to a predetermined angle in the bellows.
[0009]
According to a second aspect of the present invention, a large-diameter cylinder, a medium-diameter cylinder, and a small-diameter cylinder each having a thin walled cylinder having different diameters and having a bellows provided at an intermediate portion are nested in a concentric circle in cross section. A triple pipe for an air supply / exhaust cylinder whose one end side is fixed to each other by a horizontal bracket is bent at a predetermined angle in the bellows.
[0010]
According to the third aspect of the present invention, the jig is fitted in one end of each of a large-diameter cylinder, a medium-diameter cylinder, and a small-diameter cylinder which are arranged in a nested shape having concentric circular cross sections and are made of thin-walled cylinders having mutually different diameters. And three fitting cylinders arranged and fixed in a nested shape with concentric cross sections, and a handle fixed to the three fitting cylinders.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an elbow for a supply / exhaust cylinder according to an embodiment of the present invention, a method for manufacturing the elbow, and a jig used for the method for manufacturing the elbow will be described with reference to the drawings.
[0012]
As shown in FIGS. 1 and 2, the supply / exhaust cylinder elbow 1 has a large-diameter cylinder 2, a medium-diameter cylinder 3, and a small-diameter cylinder 4 formed of thin cylinders having mutually different diameters and provided with bellows W in an intermediate portion. A triple pipe for an air supply / exhaust cylinder, which is arranged in a concentric nest shape and one end of which is welded and fixed to each other by a horizontal bracket 5, is bent at a predetermined angle in the bellows W.
[0013]
When manufacturing the elbow 1 for a supply / exhaust cylinder, first, as shown in FIG. 3, a large-diameter cylinder 2, a medium-diameter cylinder 3, and a small-diameter cylinder formed of thin cylinders having mutually different diameters provided with bellows W in an intermediate portion. A cylinder 4 is prepared, and these cylinders 2, 3, 4 are arranged in a nest of concentric circles, and one end sides of the small-diameter cylinder 4 and the medium-diameter cylinder 3 and the medium-diameter cylinder 3 The same one end sides of the large-diameter cylinders 2 are fixed by welding at three or more places at equal intervals along the inner or outer peripheral surface. As the horizontal bracket 5, a thin plate obtained by bending a thin plate into a substantially U-shaped cross section is used. However, the shape is not limited to the illustrated shape as long as the cylinders can be fixed to each other in the above state. . However, in order to secure as much air passage area as possible, it is preferable to use a thin plate having a plate surface arranged along the flow path (the longitudinal direction of the pipe) as shown in the figure. The bellows W is provided to facilitate bending of the thin cylinders 2, 3, and 4.
[0014]
The gap between the small-diameter cylinder 4 and the middle-diameter cylinder 3 is provided smaller than the gap between the middle-diameter cylinder 3 and the large-diameter cylinder 2 so that a large cross-sectional area of the air supply and exhaust pipes is ensured. It has a simple structure. In the illustrated shape, the large-diameter cylinder 2 and the small-diameter cylinder 4 have substantially the same length, and the medium-diameter cylinder 3 is slightly shorter than the cylinders 2 and 4. Is determined by the relationship with the mating pipe to be connected, and is not limited to this length relationship. For example, the cylinders 2, 3, and 4 may all have the same length, or the medium-diameter cylinder 3 may protrude longer than the other cylinders 2, 4. One end of the small-diameter cylinder 4 is a male joint 4a whose diameter is reduced toward the distal end, and the other end of the large-diameter cylinder 2 is a male joint 2a whose diameter is reduced toward the distal end. It is a male joint (hereinafter, the side where the male side joint is formed in the small diameter cylinder 4 is referred to as “male side” and the opposite side is referred to as “female side”).
[0015]
Next, as shown in FIG. 4A, a first jig 7 is inserted into the male side of the triple pipe 6 for the supply / exhaust cylinder, and a second jig 8 is inserted into the female side thereof. Here, the first jig 7 is nested in a concentric cross section so as to be fitted into each of the large-diameter cylinder 2, the medium-diameter cylinder 3 and the small-diameter cylinder 4 on the male side of the supply / exhaust cylinder triple tube 6. Three fitted cylinders 7a, 7b, 7c, a fitted cylindrical fixing plate 7d for fixing the ends of these fitted cylinders to each other, and three fitted cylinders 7a via the fitted cylindrical fixing plate 7d. , 7b and 7c, and a first handle 7e made of a steel bar having one end fixed to the first handle 7e. The three fitting cylinders 7a, 7b, and 7c are configured to be fitted respectively along the outer peripheral surfaces of the large-diameter cylinder 2, the medium-diameter cylinder 3, and the small-diameter cylinder 4 on the male side of the supply / exhaust cylinder triple pipe 6. However, since the male-side joint shape is not provided for the medium-diameter cylinder 3 and the large-diameter cylinder 4 unlike the small-diameter cylinder 4, the fitting cylinders 7a and 7b are connected to the large-diameter cylinder 2 and the medium-diameter cylinder. It is good also as a structure which is each fitted along the inner peripheral surface of the cylinder 3. The fitting cylinder 7c disposed at the innermost side of the three fitting cylinders has a shorter pipe length than the other fitting cylinders 7a and 7b. This is to avoid interference with the horizontal bracket 5 provided on the male side of 6, and its length is determined according to the presence or absence of the horizontal bracket 5 and the mounting position of the horizontal bracket 5.
[0016]
On the other hand, the second jig 8 is nested in a concentric cross section so as to be fitted into each of the large-diameter cylinder 2, the medium-diameter cylinder 3 and the small-diameter cylinder 4 on the female side of the triple pipe 6 for the supply / exhaust cylinder. Three fitted cylinders 8a, 8b, 8c, a fitted cylindrical fixing plate 8d for fixing the ends of these fitted cylinders to each other, and three fitted cylinders 8a via the fitted cylindrical fixing plate 8d. , 8b, 8c, and a second handle 8e made of a square steel material having a predetermined length and one end of which is fixed. Among the three fitting cylinders 8a, 8b, 8c, the fitting cylinder 8c located on the innermost side is fitted along the inner peripheral surface of the small-diameter cylinder 4 on the female side of the triple pipe 6 for the supply / exhaust cylinder. The fitting cylinders 8a and 8b are fitted respectively along the outer peripheral surfaces of the large-diameter cylinder 2 and the medium-diameter cylinder 3 on the female side of the triple pipe 6 for the supply / exhaust cylinder. Note that the male-side joint shape is not provided for the medium-diameter cylinder 3 and the small-diameter cylinder 4 unlike the large-diameter cylinder 2. The fitting cylinder 8c on the inner diameter side may be fitted along the outer surface of the small diameter cylinder 4 along the surface. In addition, the three fitting cylinders 8a, 8b, 8c have slightly shorter pipe lengths toward the inner diameter side. Therefore, the fitting positions of the fitting cylinders 8a and 8c and the large-diameter cylinder 2 and the small-diameter cylinder 4 on the female side of the triple pipe 6 for the supply / exhaust cylinder are shifted back and forth, thereby facilitating the fitting operation.
[0017]
From the state shown in FIG. 4A, that is, the state where the first jig 7 and the second jig 8 are respectively inserted on both sides of the triple pipe 6 for the supply / exhaust cylinder, the second jig The second handle 8e made of a square steel material of No. 8 is inserted into the recess 9a of the work table 9 and fixed on the work table 9. Then, as shown in FIG. 4B, the first handle 7e of the first jig 7 is gripped and rotated toward the workbench 9 by a predetermined angle (90 °, 45 °, or the like), whereby the air supply / exhaust cylinder is opened. Is bent at a predetermined angle at the bellows W. At the time of bending, the fitting cylinders 7a, 7b, 7c, 8a8b, 8c of the first and second jigs 7, 8 are respectively arranged around the two ends of the cylinders 2 to 4 of the triple pipe 6 for the supply / exhaust cylinder. The two ends of the supply / exhaust tube elbow 1 manufactured through the above steps are concentrically formed without being eccentric or deformed into an elliptical shape. Is maintained. Even if the gap between the medium-diameter cylinder 3 and the small-diameter cylinder 4 is small, the cylinders 3 and 4 are evenly bent with each other.
[0018]
【The invention's effect】
According to the method for manufacturing the elbow for the supply / exhaust cylinder according to the first aspect, in the bending of the triple pipe for the supply / exhaust cylinder, the fitting cylinders of the jigs and the tools are respectively formed around the both ends of the triple pipe for the supply / exhaust cylinder. Since the pipes are fitted to each other along the plane, the triple pipe for the air supply / exhaust cylinder is bent without being eccentric or deformed into an elliptical shape, while maintaining its concentric and perfect circular shape. It can be performed. Further, even when the gap between the medium-diameter cylinder and the small-diameter cylinder for the supply / exhaust cylinder elbow is small, the gap between these cylinders is uniformly held along the peripheral surface, so An elbow for a supply / exhaust cylinder can be manufactured in which the heat loss of the exhaust pipe is sufficiently ensured and the pressure loss in the pipe is kept low.
[0019]
With the supply / exhaust tube elbow according to claim 2, it is possible to employ a triple supply / exhaust pipe as a supply / exhaust pipe for a boiler or the like, thereby improving the combustion efficiency of the boiler and the durability of the boiler. It becomes possible.
[0020]
According to the jig and tool of the third aspect, the method of manufacturing the elbow for the supply and exhaust cylinder according to the first aspect can be realized.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an elbow for a supply / exhaust cylinder according to an embodiment of the present invention.
FIG. 2 is a view as viewed in the direction of arrows AA in FIG. 1;
FIG. 3 is a longitudinal sectional view of a triple pipe for a supply / exhaust cylinder.
FIG. 4 is an explanatory view showing a manufacturing procedure of the supply / exhaust tube elbow according to the embodiment of the present invention.
FIG. 5 is an explanatory partial cross-sectional view of a double supply / exhaust cylinder elbow according to a conventional example.
[Explanation of symbols]
W Bellows 1 Elbow for supply / exhaust cylinder 2 Large-diameter cylinder 3 Medium-diameter cylinder 4 Small-diameter cylinder 5 Horizontal bracket 6 Triple pipe for supply / exhaust cylinder 7 (First) Jigs 7a to 7c Fitting cylinder 7e (First ) Handle 8 (second) jigs 8 a to 8 c fitting cylinder 8 e (second) handle

Claims

中間部に蛇腹が設けられた相互に異径の薄肉円筒からなる大径円筒、中径円筒及び小径円筒が断面同芯円の入れ子状に配置され、一端側同士が相互に横架金具によって固定された給排気筒用３重管を所定角度に屈曲する給排気筒用エルボの製造方法であって、
前記大径円筒、中径円筒及び小径円筒のそれぞれに嵌め込まれるように断面同芯円の入れ子状に配置されて固定された３つの嵌込み円筒と、該３つの嵌込み円筒に固定されたハンドルとを備える治工具を２つ用い、
前記治工具の一方を前記給排気筒用３重管の一端側に挿入嵌合し、前記治工具の他方を前記給排気筒用３重管の他端側に挿入嵌合し、
前記給排気筒用３重管の両端側に挿入嵌合された何れか一方の前記治工具を所定場所に固定し、何れか他方の前記治工具を回転させることにより、前記給排気筒用３重管を前記蛇腹において所定の角度に屈曲させることを特徴とする給排気筒用エルボの製造方法。Large-diameter cylinders, medium-diameter cylinders, and small-diameter cylinders composed of thin cylinders of mutually different diameters with bellows provided in the middle part are arranged in a nested shape with a concentric cross section, and one end side is fixed to each other by a horizontal bracket A method for manufacturing an elbow for a supply / exhaust cylinder, wherein the supplied triple pipe for an exhaust / exhaust cylinder is bent at a predetermined angle,
Three fitting cylinders arranged and fixed in a nested shape having concentric cross sections so as to be fitted into the large-diameter cylinder, the medium-diameter cylinder and the small-diameter cylinder, respectively, and a handle fixed to the three fitting cylinders Using two jigs with
One of the jigs is inserted and fitted to one end of the triple pipe for the supply / exhaust cylinder, and the other of the jig is inserted and fitted to the other end of the triple pipe for the supply / exhaust cylinder;
One of the jigs inserted and fitted at both ends of the triple pipe for the air supply / exhaust cylinder is fixed at a predetermined position, and the other jig is rotated to rotate the supply / exhaust cylinder. A method of manufacturing an elbow for a supply / exhaust cylinder, wherein a heavy pipe is bent at a predetermined angle in the bellows.

中間部に蛇腹が設けられた相互に異径の薄肉円筒からなる大径円筒、中径円筒及び小径円筒が断面同芯円の入れ子状に配置され、一端側同士が相互に横架金具によって固定された給排気筒用３重管が前記蛇腹において所定の角度に屈曲されてなることを特徴とする給排気筒用エルボ。Large-diameter cylinders, medium-diameter cylinders, and small-diameter cylinders composed of thin cylinders of different diameters with bellows provided in the middle part are arranged in a nested shape with concentric circles, and one end side is fixed to each other by a horizontal bracket Characterized in that the supplied triple pipe for the supply / exhaust cylinder is bent at a predetermined angle in the bellows.

断面同芯円状の入れ子状に配置された、相互に異径の薄肉円筒からなる大径円筒、中径円筒及び小径円筒の一端側のそれぞれに嵌め込まれるように断面同芯円の入れ子状に配置されて固定された３つの嵌込み円筒と、該３つの嵌込み円筒に固定されたハンドルと、を備えることを特徴とする治工具。Nested in a concentric circular cross-section so as to be fitted into one end of a large-diameter cylinder, a medium-diameter cylinder, and a small-diameter cylinder each having a thin-walled cylinder having different diameters arranged in a concentric circular cross-section. A jig and tool comprising three fitting cylinders arranged and fixed, and a handle fixed to the three fitting cylinders.