【０００１】
【発明の属する技術分野】
本発明は高分子溶融状物などを貯めた圧力容器点検用の閉止フランジの開閉部または配管接続部の構造に関し、特に金属ガスケットを用いてシールするシート面構造を有する圧力容器点検用の閉止フランジの開閉部または配管接続部の構造とその製造方法に関する。
【０００２】
【従来の技術】
図２の断面図に示すように、従来から圧力容器点検用の閉止フランジの開閉部から流体が漏洩することを防ぐために、圧力容器の点検用の閉止フランジの開閉部に設けられたシート面３に金属製のガスケット２を押し当てる方法が主流である。
【０００３】
また、金属ガスケット２によりシート面３が摩耗するため、シール性を維持するためにはシート面の再研磨等のメンテナンスが必要となる。この二重のガスケットを真空容器点検用の閉止フランジの開閉部に設けた発明がある（特開平１１−９４１５８号公報）。
【０００４】
また、特開平１１−１９０４３６号公報には偏心型バタフライ弁において、シール面の流体による摩耗、損傷を防止するために、シール面の流体による摩耗、損傷を防止するために断面をコサイン曲線で形成することが記載されている。
【０００５】
【特許文献１】
特開平１１−９４１５８号公報
【０００６】
【特許文献１】
特開平１１−１９０４３６号公報
【０００７】
【発明が解決しようとする課題】
前記公報記載の発明より簡易な圧力容器の点検用の閉止フランジの開閉部の密閉構造として、図３に示すように圧力容器の閉止フランジ部本体１のシート面３の金属ガスケット取り合い部に硬化肉盛溶接４を施工しておき、金属ガスケット２の押し当て時の加圧によるシート面３の摩耗を減らし、圧力容器のメンテナンスを容易にすることが考えられる。
【０００８】
しかし、図３のような高圧装置の閉止フランジ部本体１に直接硬化肉盛を施工する方法は高圧装置の安全性が損なわれるため、法的に許されないとの指導を受けた。
【０００９】
そこで、本発明の課題は、法的基準を満たしながら、流体が漏洩するのを防ぐと同時にシート面の摩耗のない圧力容器の点検用の閉止フランジの開閉部または配管接続部の構造とその製造方法を提供することである。
【００１０】
【課題を解決するための手段】
上記課題は次の解決手段で達成できる。
請求項１記載の発明は、圧力容器の点検用の閉止フランジ部または配管同士の接続部の製造方法において、前記フランジ部または配管接続部に座繰り部を設け、該座繰り部に予め硬化肉盛溶接を施工した金属ガスケットを焼きばめ、あるいは冷やしばめによって嵌合し、さらに座繰り部との金属ガスケット嵌合部表面をシール溶接した圧力容器の部材接続部の製造方法である。
【００１１】
請求項２記載の発明は、ステンレス鋼による肉盛り部を設けた後に、金属ガスケット嵌合用の座繰り部を設け、予め硬化肉盛溶接を施工した金属ガスケットを焼きばめ、あるいは冷やしばめによって嵌合し、さらに座繰り部との金属ガスケットの嵌合部表面をシール溶接した請求項１に記載の圧力容器の部材接続部の製造方法である。
【００１２】
請求項３記載の発明は、圧力容器点検用の閉止フランジ部または配管同士の接続部の構造において、前記フランジ部や接続部に金属ガスケットの嵌合用に設けた座繰り部と、該座繰り部に嵌め込んだ予め硬化肉盛溶接を施工した金属ガスケットと、前記座繰り部と金属ガスケットとの接合部表面に設けたシール溶接部とを備えた圧力容器または配管の接続部の構造である。
【００１３】
請求項４記載の発明は、圧力容器点検用の閉止フランジ部または配管同士の接続部の構造において、前記フランジ部や接続部に設けたステンレス肉盛り部と、該ステンレス肉盛り部上に機械加工により設けた座繰り部と、該座繰り部に嵌め込んだ予め硬化肉盛溶接を施工した金属ガスケットと、前記座繰り部と金属ガスケットとの接合部表面に設けたシール溶接部とを備えた圧力容器または配管の接続部の構造である。
【００１４】
【作用】
請求項１、３記載の発明によれば、圧力容器本体側に座繰り部を設け、さらにこれとは別体に予め作製した硬化肉盛溶接を施工した部材を用意しておき、該座繰り部に焼きばめ、あるいは冷やしばめにより肉盛施工部材をはめ込む。
【００１５】
座繰り部に嵌め込み後の硬化肉盛施工部材の硬化肉盛溶接施工部分は耐摩耗性が高いので、ガスケットの交換を繰り返しても硬化肉盛施工部材の劣化が少なく、また、たとえ硬化肉盛溶接施工部材が劣化しても圧力容器本体から取り外すことができるので、新品との交換が容易となる。
【００１６】
請求項２、４記載の発明によれば、それぞれ請求項１、３の発明の作用に加えて、座繰り部にステンレス肉盛り部を設けた後に、予め硬化肉盛溶接を施工した金属ガスケットを焼きばめ、あるいは冷やしばめによって嵌め込むことができ、溶接部の熱処理が不要となる作用がある。
【００１７】
【発明の実施の形態】
本発明の実施の形態を図面と共に説明する。
図１に本実施の形態となる圧力容器の点検用閉止フランジ部１のシート面の構造を示す。
【００１８】
図１（ａ）に示すように圧力容器の点検用閉止フランジ部１のガスケットの挿入部に相当する部位に嵌合用に座繰り部８を設ける。
この座繰り部８に金属ガスケットとして硬化肉盛溶接部６を予め施工したステンレス製の台金７からなる硬化肉盛リング５を挿入することに本実施例の特徴がある。硬化肉盛溶接部６を圧力容器そのものに施すのではなく、金属ガスケット自体に硬化肉盛溶接を行うので本体側に割れが発生する危険性がない。
【００１９】
得られたステンレス製の台金７に硬化肉盛溶接部６を施工した硬化肉盛リング５を図１（ｂ）に示すように、フランジ部１の座繰り部８に焼きばめ、あるいは冷やしばめをしてはめ込む。その後、座繰り部８と硬化肉盛リング５の接触面の開先内をシール溶接することでシール溶接部９を形成し、シート面（図１（ｂ）の機械加工後の面）の最終機械加工を実施する構成としている。
【００２０】
本構造により金属性のガスケット取合い部の摩耗を抑えることができる。
なお、閉止フランジ部本体１のガスケットの挿入部に予めステンレスの肉盛溶接部１０を設けることによりステンレス同士のシール溶接を行うので、シール溶接後の溶接後熱処理が不要となる。
【００２１】
【発明の効果】
請求項１、３記載の発明によれば、圧力容器およびその付属部品に直接に硬化肉盛溶接を行わずに済むのでガスケットの交換を繰り返しても硬化肉盛施工部材の劣化が少なく、また、たとえ硬化肉盛施工部材が劣化しても圧力容器本体から取り外すことができるので、新品との交換が容易となり、圧力容器のメンテナンスが容易になった。
【００２２】
請求項２、４記載の発明によれば、それぞれ請求項１、３の発明の効果に加えて、座繰り部にステンレス肉盛り部を設けた後に、予め硬化肉盛溶接を施工した部材を焼きばめ、あるいは冷やしばめによって嵌め込むために溶接後の熱処理が不要となる効果がある。
【図面の簡単な説明】
【図１】本発明の実施の形態の圧力容器の配管接続部への硬化肉盛リングの取り付け手順と取り付け後の圧力容器の配管接続部の断面構造図を示す。
【図２】従来の圧力容器の配管接続部へのガスケットの取り付け時の断面構造図を示す。
【図３】従来圧力容器の配管接続部の摩耗部に硬化肉盛を施した断面構造図を示す。
【符号の説明】
１ 圧力容器の閉止フランジ部本体 ２ 金属ガスケット
３ シート面 ４ 硬化肉盛溶接部
５ 硬化肉盛リング ６ 硬化肉盛溶接部
７ 台金 ８ 座繰り部
９ シール溶接部 １０ 肉盛溶接部[0001]
TECHNICAL FIELD OF THE INVENTION
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of an opening / closing portion or a pipe connection portion of a closing flange for checking a pressure vessel containing a polymer melt or the like, and particularly to a closing flange for checking a pressure vessel having a sheet surface structure sealed by using a metal gasket. The present invention relates to a structure of an opening / closing section or a pipe connection section and a method of manufacturing the same.
[0002]
[Prior art]
As shown in the cross-sectional view of FIG. 2, in order to prevent fluid from leaking from the opening / closing portion of the conventional pressure vessel checking flange, a seat surface 3 provided at the opening / closing portion of the pressure vessel checking flange is conventionally used. The method in which a metal gasket 2 is pressed against the main body is mainly used.
[0003]
In addition, since the metal gasket 2 wears the sheet surface 3, maintenance such as regrinding of the sheet surface is required to maintain the sealing performance. There is an invention in which this double gasket is provided at the opening / closing portion of a closing flange for inspecting a vacuum vessel (Japanese Patent Laid-Open No. 11-94158).
[0004]
Japanese Patent Application Laid-Open No. 11-190436 discloses an eccentric type butterfly valve. In order to prevent wear and damage of a seal surface by fluid, a cross section is formed by a cosine curve in order to prevent wear and damage of the seal surface by fluid. Is described.
[0005]
[Patent Document 1]
JP-A-11-94158
[Patent Document 1]
JP-A-11-190436
[Problems to be solved by the invention]
As a sealing structure of the opening / closing portion of the closing flange for inspection of the pressure vessel which is simpler than the invention described in the above-mentioned publication, as shown in FIG. It is conceivable to carry out the fill welding 4 to reduce wear of the sheet surface 3 due to pressurization at the time of pressing the metal gasket 2 and to facilitate maintenance of the pressure vessel.
[0008]
However, it has been instructed that the method of directly applying the hardfacing to the closing flange body 1 of the high-pressure device as shown in FIG. 3 impairs the safety of the high-pressure device and is not legally permissible.
[0009]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a structure of an opening / closing portion or a pipe connection portion of a closing flange for inspection of a pressure vessel which prevents a fluid from leaking and which does not have a seat surface while satisfying legal standards, and manufacturing the same. Is to provide a way.
[0010]
[Means for Solving the Problems]
The above object can be achieved by the following means.
The invention according to claim 1 is a method for manufacturing a closed flange portion for inspecting a pressure vessel or a connection portion between pipes, wherein a counterbore portion is provided at the flange portion or the pipe connection portion, and the countersunk portion is previously hardened meat. This is a method for manufacturing a member connection portion of a pressure vessel in which a metal gasket subjected to fill welding is fitted by shrink fitting or cold fitting, and furthermore, the surface of the metal gasket fitting portion with the counterbore portion is seal-welded.
[0011]
The invention according to claim 2 is to provide a counterbore for fitting a metal gasket after providing a built-up portion made of stainless steel, and shrink-fit or cool-fit a metal gasket that has been subjected to hardening welding in advance. 2. The method according to claim 1, wherein the fitting is performed, and the surface of the fitting portion of the metal gasket with the counterbore portion is seal-welded.
[0012]
According to a third aspect of the present invention, in the structure of a closing flange portion for pressure vessel inspection or a connecting portion between pipes, a counterbore portion provided for fitting a metal gasket to the flange portion or the connecting portion, and the counterbore portion are provided. This is a structure of a pressure vessel or pipe connecting portion provided with a metal gasket which has been previously subjected to hardfacing welding and is fitted with a seal welding portion provided on a surface of a joint between the counterbore portion and the metal gasket.
[0013]
According to a fourth aspect of the present invention, in the structure of the closing flange portion for pressure vessel inspection or the connecting portion between the pipes, a stainless build-up portion provided on the flange portion or the connecting portion, and machining on the stainless build-up portion is provided. And a metal gasket fitted with the counterbore and subjected to hardened overlay welding, and a seal weld provided on the surface of the joint between the counterbore and the metal gasket. It is the structure of the connection part of a pressure vessel or piping.
[0014]
[Action]
According to the first and third aspects of the present invention, a counterbore portion is provided on the pressure vessel main body side, and a member on which a hardfacing weld prepared in advance and prepared in advance is prepared separately from the counterbore portion. Insert the overlay material by shrink fit or cold fit into the part.
[0015]
The hardfacing welded part of the hardfacing member after fitting into the counter bore has high abrasion resistance, so there is little deterioration of the hardfacing material even if gaskets are replaced repeatedly. Even if the welding member deteriorates, it can be removed from the pressure vessel main body, so that replacement with a new one becomes easy.
[0016]
According to the inventions of claims 2 and 4, in addition to the effects of the inventions of claims 1 and 3, a metal gasket which has been subjected to hardfacing welding in advance after providing a stainless overlay on the counterbored portion is provided. It can be fitted by shrink fit or cold fit, and has the effect of eliminating the need for heat treatment of the welded portion.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a structure of a seat surface of an inspection closing flange portion 1 of a pressure vessel according to the present embodiment.
[0018]
As shown in FIG. 1A, a counterbore 8 is provided for fitting at a position corresponding to the gasket insertion portion of the inspection flange 1 of the pressure vessel.
This embodiment is characterized in that a hardfacing ring 5 made of a stainless steel base metal 7 on which a hardfacing welded portion 6 is preliminarily applied as a metal gasket is inserted into the counterbore 8. Since the hardfacing weld 6 is not applied to the pressure vessel itself, but the hardfacing welding is performed on the metal gasket itself, there is no danger of cracks occurring on the main body side.
[0019]
As shown in FIG. 1 (b), the hardfacing ring 5 obtained by applying the hardfacing welded portion 6 to the obtained stainless steel base metal 7 is shrink-fitted to the counterbore portion 8 of the flange portion 1 or cooled. Fit and fit. Thereafter, a seal welding portion 9 is formed by seal-welding the inside of the groove of the contact surface between the counterbore portion 8 and the hardfacing ring 5, and the final surface of the seat surface (the surface after machining in FIG. 1B) is formed. It is configured to carry out machining.
[0020]
With this structure, the wear of the metallic gasket joint can be suppressed.
The seal welding between the stainless steels is performed by providing the stainless steel overlay welding portion 10 in advance in the gasket insertion portion of the closing flange portion main body 1, so that post-weld heat treatment after the seal welding is unnecessary.
[0021]
【The invention's effect】
According to the first and third aspects of the present invention, it is not necessary to directly perform the hardfacing welding on the pressure vessel and its attached parts, so that even if the gasket is exchanged repeatedly, the deterioration of the hardfacing member is small, and Even if the hardfacing member deteriorates, it can be removed from the pressure vessel main body, so that replacement with a new one is easy and maintenance of the pressure vessel is easy.
[0022]
According to the second and fourth aspects of the present invention, in addition to the effects of the first and third aspects of the present invention, a member which has been subjected to hardfacing welding in advance after providing a stainless overlay on the counterbore is provided. There is an effect that heat treatment after welding is unnecessary because the fitting is performed by fitting or cold fitting.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a procedure for attaching a hardfacing ring to a pipe connection of a pressure vessel and a cross-sectional structure of the pipe connection of the pressure vessel after the attachment according to the embodiment of the present invention.
FIG. 2 is a cross-sectional structural view when a gasket is attached to a pipe connection part of a conventional pressure vessel.
FIG. 3 is a cross-sectional structural view in which a hardened portion is applied to a worn portion of a pipe connection portion of a conventional pressure vessel.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 closing flange body of pressure vessel 2 metal gasket 3 sheet surface 4 hardfacing weld 5 hardfacing ring 6 hardfacing weld 7 base metal 8 counter bore 9 seal weld 10 overlay weld
