JPS58214832A - Weld crack detection for multi-layer wrapped pressure vessel - Google Patents

Abstract

PURPOSE:To capture the position and the form of weld cracks by detecting variation in the original pressure or gas from adjacent layers when gas is forced into layers of a multi-layer wrapped pressure vessel through a gas feed hole provided communicating between layers. CONSTITUTION:In a multi-layer wrapped pressure vessel, an inverted-cone-shaped detection hole T1 is drilled so as to reach the surface of the innermost layer 3 from the outermost layer 10 and a nozzle 11 is fitted thereinto. Gas pressure feed heads 12-14 adapted to force gas in groups between layers ended in inter- layer 13, 11 and 12 arranged at invervals of 4 inter-layers starting from inter- layers 1, 2 and 3 and a detection head 15 for checking the sealing property of inter-layers are projected on the top surface of the nozzle 11. A valve 17 is opened to feed a gas to the head 12 with a fixed pressure in a high pressure vessel 23 and the sealing property of an O ring 16 with a head 15. Then, the presence, the position and the form of weld cracks are captured depending on the outflow of the gas from the heads 13 and 14 or drop in the pressure of a manometer 24.

Description

【発明の詳細な説明】 本発明は、各層毎ＫＶシーム溶接部ある多層巻圧力容器
における前記シーム溶接部の割れを、簡墨な手段で検知
する方法に関し、詳細には、製造直後及び使用中の如何
を問わず、常に正確な検知結果を得ることのできる方法
に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for detecting cracks in seam welds in a multi-layer pressure vessel having KV seam welds in each layer by a simple means, and in particular, immediately after manufacture and during use. The present invention relates to a method that can always obtain accurate detection results regardless of the situation.

多層巻圧力容器は薄板を材料とするものであるから、材
料面での信頼性が高く、又高強度薄板を使用するもので
は破壊抵抗も大きくなるという利点がある。又製造過程
から見れば、単層圧力容器のル造に２ける問題点（造塊
能力、鍛造プレス能力、臼げ加工能力等）にポ遇するこ
とがないという利点もある。その為各種化学工業分野に
おいて注目を集めているが、溶接部の割れを外部から発
見することができないという間口があった為、せいぜい
４００℃程度迄の温度環境下に２いて、しかも内圧変化
や温度変化の少ない様な用途、換言すれば採返し荷重の
η・からない緩和な条件下に用いる容器として利用され
てきたに過ぎず、信頼性において十分とは言えない。そ
の為繰返し荷重のかかるような条件下で使用される容器
の開発纜おいては表ａ直後は勿論のこと、使用中におい
ても溶接部の割れを正確にしかも簡単に検知し徨る方法
の開発が渇望されているが、未だ提供されるに至ってい
ない。Since the multilayer pressure vessel is made of thin plates, it has the advantage of being highly reliable in terms of materials, and the use of high-strength thin plates has the advantage of increased fracture resistance. Also, from the perspective of the manufacturing process, there is the advantage that the two problems (ingot-forming ability, forging press ability, mortaring ability, etc.) that occur when manufacturing a single-layer pressure vessel are not encountered. For this reason, it has attracted attention in various chemical industry fields, but because cracks in welds cannot be detected from the outside, they are exposed to temperatures of up to 400 degrees Celsius at most, and there are no changes in internal pressure. It has only been used as a container for applications where there is little temperature change, in other words, under mild conditions where there is no return load η, and it cannot be said that its reliability is sufficient. Therefore, in the development of containers that are used under conditions where repeated loads are applied, we need to develop a method to accurately and easily detect and detect cracks in welds, not only immediately after table a, but also during use. is desired, but has not yet been provided.

即ち多層巻圧力容器としては色々の製造手段が有シ、極
めて広い面積の板をコイル状に巻上げ最終着付部を重ね
継手の要領に従って軸方向に溶接するという方法も開発
されているが、縦方向及び横方向にひろがる広大な表面
積を有する薄板を製造すること自体に制約があシ、又こ
の様な大面積薄板をコイル状に巻上げていくという技術
にも色々な難点があシ、汎用性に欠けている。従って多
数の溶接部を内包する次の様な方法に頼らざるを得ない
面があって、外部から観察できない溶接部における割れ
の検知が重大な課題となってきている。即ち現在もつと
も広く行なわれている溶接手順を第１〜４図に従って説
明すると、まず第１１ヌ１は円筒型１の外周に８枚の薄
板（通常６〜１５−）２ａ、２ｂ、２ｃｉ巻付け、突合
わせ部を軸方向に溶接してシーム継手２’　ａ　、　２
Ｌ　ｂ　、　２／　ｃを形成する。第２図では最内層薄
板２のまわりに８枚の薄板３ａ、３ｂ、３ｃを湾曲する
様に添設し、３本の突合わせ部を軸方向に溶接してシー
ム継手３′ａ。In other words, there are various manufacturing methods for multilayer pressure vessels, and a method has been developed in which a plate with an extremely wide area is rolled up into a coil shape and the final attachment part is welded in the axial direction according to the method of lap joints, but There are limitations in manufacturing thin sheets with a vast surface area that spreads in the lateral direction, and there are also various difficulties in the technology of winding such large-area thin sheets into coils, making it less versatile. Missing. Therefore, it is necessary to rely on the following method that involves a large number of welds, and detection of cracks in welds that cannot be observed from the outside has become a serious issue. That is, to explain the welding procedure that is currently widely used in accordance with Figs. , butt portions are welded in the axial direction to form a seam joint 2'a, 2
Form L b , 2/c. In FIG. 2, eight thin plates 3a, 3b, and 3c are attached in a curved manner around the innermost thin plate 2, and the three butt parts are welded in the axial direction to form a seam joint 3'a.

３’ｂ、３’ｃを形成する。同シーム継手は前層のシー
ム継手上へ重ならない様に少しずつずらせておく（以下
同様）。第３図では更にその上へ３枚の薄板４ａ、４ｂ
、４ｃを添設し゛て夫々シーム継手４′＆、　４：ｂ　
、イＣを形成し、第４図では更にその上へ８枚の薄板５
ａ、５ｂ、５ｃを添設して夫々シーム継手５’ａ　、　
５’ｂ　、　５’ｃを形成している。以後同様の手順を
重ねて多数の暦からなる多層巻円筒体とし、最後Ｋ又は
途中の任意の段階で円筒型１を脱出させ、謬円筒体同士
並びに適当な鏡板を突合わせ円周溶接して多層巻圧力容
器を製造して込る。但しこの方法であると各層毎に３本
のシーム継手を溶接する必要があるので、積層していく
薄板を２つ割りのものとしてシーム継手を各層２本ずつ
としたシ、第５．６図に示す如（薄板を１枚ずつ（８，
４・−−−−−）巻付は夫々１本のシーム邂手溶接（３
′、イ−−−−−）で層を重ねていくという方法もある
。これらの方法では前述のコイル巻き方式で見られた様
な欠、点がない為、現在の多層巻圧力容器の製造におけ
る主流となシつつあるが、各層のシーム継手溶接線は夫
々その外周に巻層される薄板によって覆われた外部から
の観察が不可能になるだけでなく、超音波探傷法を適用
しようとしても各層間に隙間ができている為信頼性の高
い結果を得ることはできない。そして内部に隠されたこ
の様な各溶接部に発生する欠陥については、今のところ
正確に検知する方法が見出されていない。冑これもの多
層円筒体を圧力容器として組立てた後において、該圧力
容器の鞠心と直交する方向に最内層の表面まで到達する
穴をｍ１１１Ｉｔ、、容器内の高圧ガスが上記の穴を通
して漏出してくるのを検知して溶接割れを発見しようと
いう方法も捉案されているが、この方法によれば、最内
層のシーム継手（第１〜６図の２′）に割れが発生した
場合Ｋ、容器内のガスが割れ部を通して最内層とその外
周Ｊ！ＤＣ漏出し、これが前記の穴に振散してきて検知
されるものであるから、最内層溶接部の割れが発見され
るだけであって、２Ｍ目、８Ｈ目。3'b and 3'c are formed. The same seam joint is shifted little by little so that it does not overlap the seam joint of the previous layer (the same applies hereafter). In Fig. 3, three thin plates 4a and 4b are added above it.
, 4c are attached respectively to seam joints 4'& 4:b.
, form A C, and in Fig. 4, eight thin plates 5 are further placed on top of it.
Seam joints 5'a, 5b and 5c are attached respectively.
5'b and 5'c are formed. Thereafter, the same procedure is repeated to form a multi-layered cylindrical body consisting of a large number of calendars, the cylindrical mold 1 is removed at the end K or at any stage along the way, and the cylindrical bodies and a suitable end plate are butt-welded and circumferentially welded. Manufacture and install multi-layer pressure vessels. However, with this method, it is necessary to weld three seam joints for each layer, so we split the laminated thin plates into two and made two seam joints for each layer, Figure 5.6. As shown in (8)
4・------) Winding is done by hand welding one seam each (3
There is also a method of stacking layers using ``, i------). Since these methods do not have the drawbacks seen in the coil winding method described above, they are becoming mainstream in the production of current multilayer pressure vessels, but the seam joint welding line of each layer is Not only is it impossible to observe from the outside as it is covered by the rolled thin plates, but even if you try to apply ultrasonic flaw detection, it is impossible to obtain highly reliable results because there are gaps between each layer. . As of now, no method has been found to accurately detect defects that occur in each welded part and are hidden inside. After assembling this multilayer cylindrical body as a pressure vessel, the high pressure gas inside the vessel leaks through the hole m111It, which reaches the surface of the innermost layer in the direction perpendicular to the center of the pressure vessel. A method has also been proposed to detect weld cracks by detecting the occurrence of cracks in the weld, but according to this method, if a crack occurs in the innermost seam joint (2' in Figures 1 to 6), , the gas inside the container passes through the crack to the innermost layer and its outer circumference J! Since the DC leakage is detected when it is dispersed into the hole mentioned above, a crack in the innermost layer weld is only discovered at the 2M and 8H.

４−目、・−・・・・の浴接割れを発見することは不可
能である。4-It is impossible to discover the bath contact cracks.

本発明はこの様な状況に着目してなされたものであって
、多層巻圧力容器の細心と直交する方向に最内層の表面
まで到達する検知穴を掘削し、ある層間に流体を圧入し
たときの元圧の変動又は近接する層間からの前記流体の
検出をもって、前記層間に臨設形成されたシーム溶接部
の割れを検知することのできる方法を提供するものであ
る。従って容器製造の直後は勿論のこと、実際に使用し
ている途中においても内部の非破壊検査が可能となった
ものであ）、多層巻圧力容器の使用中の変化が検知でき
るので、安心して色々の用途に利用することが可能とな
った。The present invention has been made with attention to such a situation, and is based on the following: When a detection hole reaching the surface of the innermost layer is drilled in a direction perpendicular to the fine details of a multi-layered pressure vessel, and fluid is injected between certain layers. The present invention provides a method capable of detecting cracks in a seam weld temporarily formed between the layers by detecting fluctuations in the source pressure of the fluid or the fluid from adjacent layers. Therefore, it is now possible to conduct non-destructive inspections of the inside of a multilayer pressure vessel, not only immediately after manufacturing, but also during actual use. It has become possible to use it for various purposes.

第７図は本発明にお行る溶接割れ発見の原理を示す断面
説明図であ）、各薄板の層間を理解し易くする為誇大し
て示し、夫々■１■、■で表わす。FIG. 7 is an explanatory cross-sectional view showing the principle of detecting weld cracks according to the present invention). In order to make it easier to understand, the interlayers of each thin plate are exaggerated and are represented by ■1■ and ■, respectively.

そして最内層管２０表面に到達する検知穴Ｔ１゜Ｔ２が
形成され、流体通過孔を有するノズル部材８．９が夫々
挿入されている。又Ｍは紙面を貫通する方向に形成され
たシーム溶接の溶接金属を示し、図では母材との境界面
に溶接割れＷｌが発生している。溶接割れＷｌを発見す
る手段としては２通りあって、いずれの方法をとるにせ
よ加圧流体（以下代表的に加圧ガスと述べる）を矢印入
方向から供給し、ノズＶ部材８を壽して層間■内へ吹込
む。吹込まれたガスは層間■、溶接割れ＝ｒ　１及び層
間■を迩してノズル部材９に至り、矢印Ｂ方向へ回収さ
ｎる１、従って加圧ガス供給側における元圧低下、又は
叩圧ガヌ凹収偶１におけるガス圧の増大若しくはガスの
存在（特殊ガスの場合）を検知することができ、これら
のいずれたカ；検知された場合に溶接割れｗｌの存在力
；推察される。晶溶ツ言Ｊれとしては、第８区に示す妬
＠中火貢通ｉ」れＷ２がありこの場合は層間■と層間■
、並びに層間■と層間■が連通されることがな（、層間
■と層間■が連通される。従って例えば加圧力″ス全矢
印Ａから層間■に圧入し、層間■からノズル部材９を介
して矢印Ｂ方向へ通過させることによっテ溶接ｉ＋れＷ
２の存在を推察すれげ艮ｌ／）。檗９゜１０図は溶接割
れの他のパターンを示すもので、第９図でに層間（２）
と層間■力Ｓ連通されているので第７図の手段を応用す
れば溶接割れＷ３として検知することができ、第１０図
では、＠間■、■、■が相互に連通されるので、層間■
と層間■の間、及び層間■とＷ１１５■の間に第７図の
手段を適用するか、層間■と功闇■の間に第８図の手段
を適用すれげ艮く、これらの手段によって全てｌｊれの
存在が検知されれは浴ｖ：割れＷ４と判断することがで
きる。Detection holes T1 and T2 reaching the surface of the innermost tube 20 are formed, and nozzle members 8 and 9 each having a fluid passage hole are inserted therein. Further, M indicates weld metal of seam welding formed in a direction penetrating the plane of the paper, and in the figure, a weld crack Wl has occurred at the interface with the base metal. There are two ways to discover weld cracks Wl. In either method, pressurized fluid (hereinafter typically referred to as pressurized gas) is supplied from the direction of the arrow, and the nozzle V member 8 is closed. Inject into the interlayer ■. The injected gas passes through the interlayer ■, weld crack = r1, and interlayer ■, reaches the nozzle member 9, and is recovered in the direction of arrow B. Therefore, the source pressure decreases on the pressurized gas supply side, or the beating pressure An increase in gas pressure or the presence of gas (in the case of a special gas) in the concave joint 1 can be detected, and if either of these is detected, the existence of a weld crack wl can be inferred. For example, there is W2 shown in the 8th ward, and in this case, the interlayer ■ and the interlayer ■
, and the interlayers ■ and the interlayers ■ are not communicated (the interlayers ■ and the interlayers ■ are communicated. Therefore, for example, the pressurizing force "is pressed into the interlayer ■ from the full arrow A, and from the interlayer ■ through the nozzle member 9. By passing it in the direction of arrow B, welding
I can infer the existence of 2. Figure 9.10 shows another pattern of weld cracking.
Since the interlayer ■ force S is in communication with each other, it can be detected as a weld crack W3 by applying the means shown in Fig. 7. In Fig. 10, the interlayer ■, ■, and ■ are in communication with each other, so the interlayer ■
By applying the means in Figure 7 between the layer ■ and the layer ■ and between the layer ■ and W115■, or applying the means in Figure 8 between the layer ■ and the darkness ■, by these means. If the presence of all lj cracks is detected, it can be determined that there is a bath v: crack W4.

次に本発明の方庄を今少し具体的に（しかし原理的に）
説明したのが第１１図である。多層巻圧力容器の層数は
設計圧力により異なるが以下説明の都合上１４°すとす
る。また、々釦孔を３つの集団に分け、各集団毎に２つ
おきの層間ごとにノズル部材のガス孔２５を臨ませるこ
ととする。即ち第１集団においては、層間○゛、　＜１
．　　・ｊ　、　Ｑ＋ｌ＋　、○、第２鶏団、でおいて
は層間■、■、■、■、第３集団）１ においては畳量■、■、■、０の夫々にガノス孔２５を
臨ませている。商図の左側は上記ガス孔の配列を示し、
右側には検出可能欠陥（上方のＷ１〜Ｗ４は前出の意味
）を対応する様に示している。今再１集団についてガス
を圧入し、ノズル部材の各ガス孔２５から層間σ）、■
、■、■、■へいつせいにガスを圧入したとする。この
時もし［相］で示す溶接割れＷｌがあったとすれば、最
外層部からのガス漏れ又は元圧の低下が観測される（同
以後の説明においてに元圧の低下についての記載を省略
する）。又■で示す溶接割れがあつ九とすると、層間■
からのガスが層間■に入るので検出口Ｏからのガス漏れ
が観測される。又■で示す溶接割れＷ４があったとする
と、層間■が層間■、■の両方に連通されるので、検出
口■、■の両方からガス漏れが観測される。又ので示す
溶接割れＷ２があったとすると、層間■と層間■が連通
されるので、検出口０からガス漏れが観１ｆＩｌｌされ
る。図番をもって示さなかった残りの溶接割れについて
も同様にして検知され、検知が完了すると、今度は第２
集団へガスを圧入して同様の検知操作を行ない、次いで
更に第３集団へのガス圧入に切替えて検知操作を完了す
る。上記各説明においては、溶接割れがある場合におけ
る各検出口でのガス漏れ状況を述べたが、各検出口にお
けるガス漏れ状況から溶接割れの位置及び種類（第１〜
４図のいずれか）を全て確定することは、溶接割れ箇所
が増大してほとんどの層間が連通される場合もあること
を考えると極めて難事である。従って製造直後は勿論の
こと使用期間中においても定期的且つ頻繁に検知操作を
行ない、浴接割れの早期発見に努めれば、溶接割れの位
置及び種類を１つずつ正確に検知していくことができる
。しかし溶接割れの数が増大していくにつれてガス漏れ
の観測される検出口の分布が広がってくるので、予め個
々の答接割れに対応するガス漏れ状０の相関表を作放し
ておき、これに基づいて新しい溶接割れの発見に努める
ことが推奨されるみ 次に本発明において用いられる具体的な装置例を示し、
これに基づいて溶接割れを検知する手：１シについて説
明する。第１２図は本発明装置において用いられるノズ
ル部材（以下車にノズＡ／）の平面図、第１３図は検知
穴へノズルを装置した状■を示す要部破＃ｒ圃面図であ
る。多層巻圧力容器には、最外層ｌＯから最内層２の表
面に到達する逆円錐台状の検知穴Ｔ１が掘削され、ノズ
ル１１カＳ嵌合される。ノズル１１の頂面には、前述の
第１〜８集団毎に夫々ガスを圧入することのできるガス
圧入ヘッド１２．１８．１４（！：、各層間のシール性
を調べる為の検出ヘッド１５が突設されており、第１集
団に映厄するヘッド１２には第１１図に示した層間■、
■、■、０υ、○へ通ずるガス送入孔２５（５不）が穿
設され他のヘッド１８．１４には夫々他の層間に通ずる
各４木のガス送入孔が穿設されている。同各層毎に検知
穴内周面とノズル１１の外周面との市には夫々２本ずつ
の。−リング１６が装着されて２シ、圧入ガスが検知穴
内周面とノズル外周面の間から漏出するのを防止してい
るが、万が一禰出があった場合には、ガス抜き穴２０の
いずれかを通してガスが排出されてシール不良箇所が検
出されるので、当該位置に袋層されているＯ−リング１
６を取替えれば良い。こうして漏出のないことがａ認さ
れた後で、第１１図の手１頃に従ってパルプ１７〜１９
を作動し、溶接割れに基づく層間の連通を検出していく
。同各Ｏ−リングのシール特性に充分な信・槓性が逼ら
れるとさは、ガス漏れを検出する為だけの検出ヘッド１
５及びこれに続くガス抜き穴２０の全てを排除し、第１
〜３集団に対厄するヘッド１２．１３゜１４及びそれに
設けられるガス送入孔だけで横圧しｆ第１４．１６凶参
照）、且つシール用のＯ−リングは各層横圧材１枚毎に
１本ずつ配設するだけで良い。Next, I will explain the method of the present invention a little more concretely (but in principle).
The explanation is shown in FIG. 11. Although the number of layers of the multi-layer pressure vessel varies depending on the design pressure, it is assumed to be 14 degrees for convenience of explanation below. Further, each button hole is divided into three groups, and the gas holes 25 of the nozzle member are made to face every second layer in each group. That is, in the first group, the interlayer ○゛, <1
．．・J, Q+l+, ○, 2nd chicken group, interlayer ■, ■, ■, ■, 3rd group) 1, make Ganosu hole 25 face each of the tatami volume ■, ■, ■, 0. ing. The left side of the commercial diagram shows the arrangement of the gas holes mentioned above,
On the right side, detectable defects (W1 to W4 above have the same meanings as above) are shown in a corresponding manner. Now, pressurize gas for one group again, and interlayer σ) from each gas hole 25 of the nozzle member, ■
Suppose that gas is injected into , ■, ■, and ■. At this time, if there is a weld crack Wl shown in [phase], gas leakage from the outermost layer or a drop in the source pressure will be observed (the description of the drop in the source pressure will be omitted in the following explanation) ). Also, if the weld crack shown by ■ is 9, the interlayer ■
Gas leakage from the detection port O is observed because the gas from the layer enters the interlayer ■. Furthermore, if there is a weld crack W4 indicated by ■, the interlayer ■ communicates with both the interlayers ■ and ■, so gas leakage is observed from both the detection ports ■ and ■. If there is a weld crack W2 as shown in the figure below, gas leakage from the detection port 0 is detected because the interlayers ■ and interlayers ■ are communicated with each other. The remaining weld cracks not shown with drawing numbers are detected in the same way, and once the detection is completed, the second weld crack is detected.
A similar detection operation is performed by pressurizing gas into the group, and then switching to gas injection into a third group to complete the detection operation. In each of the above explanations, we have described the gas leakage situation at each detection port when there is a weld crack, but the position and type of weld crack (first to
It is extremely difficult to determine all of the problems shown in Figure 4, considering that the number of weld cracks may increase and most of the layers may be in communication. Therefore, if you perform detection operations regularly and frequently not only immediately after manufacture, but also during use, and strive to detect bath weld cracks early, you will be able to accurately detect the location and type of weld cracks one by one. I can do it. However, as the number of weld cracks increases, the distribution of detection ports where gas leaks are observed expands, so a correlation table of 0 gas leaks corresponding to each weld crack is prepared in advance. It is recommended that efforts be made to discover new weld cracks based on
Based on this, the first method for detecting weld cracks will be explained. FIG. 12 is a plan view of a nozzle member (hereinafter referred to as nozzle A/) used in the apparatus of the present invention, and FIG. 13 is a broken-down field view of the main parts showing the state in which the nozzle is installed in the detection hole. A detection hole T1 in the shape of an inverted truncated cone is drilled in the multilayer pressure vessel, reaching from the outermost layer 1O to the surface of the innermost layer 2, and a nozzle 11 S is fitted into the detection hole T1. On the top surface of the nozzle 11, there are gas injection heads 12, 18, 14 (!:, detection heads 15 for checking the sealing properties between each layer) that can pressurize gas into each of the above-mentioned 1st to 8th groups. The head 12, which is projected and projected onto the first group, has interlayers shown in FIG.
Gas inlet holes 25 (5 not included) are drilled that lead to ■, ■, 0υ, and ○, and four gas inlet holes are drilled in each of the other heads 18 and 14 that lead to the other layers. . In each layer, two wires are provided between the inner peripheral surface of the detection hole and the outer peripheral surface of the nozzle 11. - When the ring 16 is installed, it prevents the press-fit gas from leaking from between the inner peripheral surface of the detection hole and the outer peripheral surface of the nozzle. Gas is discharged through the O-ring 1, which is sealed at that position, and the seal failure is detected.
6 should be replaced. After confirming that there is no leakage in this way, pulps 17 to 19 are processed according to the first part of Figure 11.
is activated to detect communication between layers based on weld cracks. If the sealing characteristics of each O-ring have sufficient reliability and reliability, the detection head 1 only for detecting gas leaks can be used.
5 and all of the gas vent holes 20 following this, and the first
~ 3 groups of heads 12.13゜14 and the gas inlet holes provided there are used to apply lateral pressure (see Section 14.16), and O-rings for sealing are attached to each layer of lateral pressure material. All you need to do is place them one by one.

次に第１３図の装置を用いて溶接割れの検品を行なう場
合の具体的手順について説明する。まずパルプ２２．１
７を開き、高圧容器２３内の圧力を例えばＰｌに設定す
ると共に第１集団の各ガス送入孔から各蓄量■、■、■
、［相］、ＤＫ加圧ガスを充満させ、前述の圧力が２１
でＶ定したことを確認してからパルプ２２を閉じる。ガ
ス漏れ検出ヘッド１５からのガス漏れの有霊を検知して
〇−リングによるシール性が確大であることを確認した
後、第１１図について述べた手順に従って第２集団のヘ
ッド１３及び第３集団のヘッド１４からのガスの流出、
あるいは圧力計２４による高圧容器２３内の圧力低下を
見て溶接割れの有無を知る。Next, a specific procedure for inspecting weld cracks using the apparatus shown in FIG. 13 will be described. First, pulp 22.1
7 and set the pressure inside the high-pressure container 23 to, for example, Pl, and at the same time, the respective accumulated amounts ■, ■, ■ are sent from each gas inlet of the first group.
, [phase], DK is filled with pressurized gas, and the above pressure is 21
After confirming that V is set at , the pulp 22 is closed. After detecting gas leakage from the gas leak detection head 15 and confirming that the sealing performance by the O-ring is reliable, the second group of heads 13 and the third group are outflow of gas from the collective head 14;
Alternatively, the presence or absence of weld cracking can be determined by checking the pressure drop in the high-pressure vessel 23 measured by the pressure gauge 24.

尚ヘッド１８．１４からのガスの流出を検知するに当っ
ては、ガス送入孔の空気出口に石けん水を塗って気泡の
発生を調べるか、特殊なガス（例えばフレオンガスやＨ
ｅガス等）を用いた場合は夫夫専用のガス検知器を用い
て確認する。又圧力計２４によって溶接割れの存在を確
認する場合、一時的に圧力低下があるだけであって以後
一定圧力を示すときは、溶接割れ無しと判定する方が良
い。When detecting the outflow of gas from the head 18.14, either apply soapy water to the air outlet of the gas inlet hole and check for bubbles, or use a special gas (such as Freon gas or H
If gas (e.g. gas, etc.) is used, check using a gas detector designed specifically for the husband. Further, when confirming the presence of weld cracks using the pressure gauge 24, if there is only a temporary pressure drop and the pressure remains constant thereafter, it is better to determine that there is no weld crack.

もし溶接割れがあれば、圧力計２４の指針は時間の経過
と共Ｋ　１１１　ｉＲして低下するので容易に区別する
ことができる。If there is a weld crack, it can be easily identified because the pointer of the pressure gauge 24 decreases as K 111 iR over time.

第１３図の例では、各ヘッド１２，１８．１４に対して
共通の畳圧容器２３を接続した系、第１４図に示す様Ｋ
、各ヘッド毎に夫々別個の高圧容器を接続することもで
きる。同図においてサフィックスａ、ｂ、ｃを付した各
記号は第１２．１８図の場合と同じ意味を示す。即ち第
１〜３の各集団のヘッド１２．１８．１４には、夫々独
立した別個の高圧容器２８ａ、２３ｂ、２８ｃｆＫ接現
され、夫々ｐ１．ｐ２．ｐ３の圧力をもったガス体を導
入する（但しＰＬ＞Ｐ２＞Ｐ３　’）。そしである時間
が経過し圧力計２４ａ、２４ｂ、２４ｃの指針が安定し
た状■に至ると、パルプ２２　ａ　、　２２　ｂ。In the example shown in FIG. 13, a system in which a common tatami pressure container 23 is connected to each head 12, 18.14, K as shown in FIG.
, it is also possible to connect a separate high-pressure vessel to each head. In the figure, each symbol with suffixes a, b, and c has the same meaning as in FIG. 12.18. That is, the heads 12, 18, and 14 of each of the first to third groups are provided with independent high-pressure vessels 28a, 23b, and 28cfK, respectively, and p1. p2. A gas body having a pressure of p3 is introduced (PL>P2>P3'). Then, after a certain period of time has passed and the pointers of the pressure gauges 24a, 24b, 24c reach a stable state (3), the pulps 22a, 22b.

２２Ｑを閉じ各高圧容器２ａａ、２ａｂ、２ａｃ内の圧
力変動状況をＩＩｌ察する。溶接割れが発生しておらな
ければ圧力Ｐ　ｌ　＊　Ｐ　２　ｓ　Ｐ　３はほとんど
変化しないが、ＩＭ割れＷｌ、２層割れＷ４．浴接中心
割れＷ２が発生していたとすると、第１５図に示す様な
圧力変１が観察される。即ち（ム）の場合は、ＰｌとＰ
２の圧力差がならされる方向、（ｂ＋の場合ｔｉＰ１．
Ｐ２．Ｐ３の圧力差がならされる方向、（Ｃ）の場合は
ＰｌとＰ２の圧力差がならされる方向に夫々圧力変動か
起こり、例えば第１５認１の右１１１ｍ１Ｋ示す様な変
化ｆ）ｓ観測される。但し圧力変化の絶対量と溶接害ｊ
れの棚頑との間には直接的な因果関係は認められず、又
溶接割れの発生した櫂を見出すことにできない。しかし
測定が容易である為連現的観察には通している。尚Ｐｌ
＝Ｐ２＋Ｐ３のうち１つ（具体的にはＰ３）を大気圧に
して測定する場合もあるが、前述の第１集団をＰ３に伊
続すると、最内層に溶接割れが発生してもこれを発見す
ることができないので、最内層の外周面（第１１図にお
ける層間■）を大気圧に連通させる方式は回避すべきで
ある。22Q is closed and the pressure fluctuations inside each high pressure container 2aa, 2ab, 2ac are observed. If no weld cracks occur, the pressure P l * P 2 s P 3 will hardly change, but if there is an IM crack Wl, a two-layer crack W4. If a bath contact center crack W2 had occurred, a pressure change 1 as shown in FIG. 15 would be observed. That is, in the case of (mu), Pl and P
The direction in which the pressure difference of 2 is equalized, (for b+, tiP1.
P2. Pressure fluctuations occur in the direction in which the pressure difference at P3 is smoothed out, and in the case of (C), in the direction in which the pressure difference between Pl and P2 is smoothed out. For example, changes such as the one shown at 111m1K on the right in No. 15 Acknowledgment 1 f) s observation be done. However, the absolute amount of pressure change and welding damage
There is no direct causal relationship between this and the other paddles, and no paddles have been found that suffered from weld cracks. However, since it is easy to measure, it can be used for continuous observation. ShoPl
= One of P2 + P3 (specifically P3) may be measured at atmospheric pressure, but if the first group described above is continued to P3, even if a weld crack occurs in the innermost layer, it will be detected. Therefore, a system in which the outer circumferential surface of the innermost layer (interlayer ■ in FIG. 11) is communicated with atmospheric pressure should be avoided.

第１６図は他の実施例装置を示す断面図、第１７図はそ
の平面図を示す。ノズルには、層間の数に対応するだけ
のガス送入孔２５（１４木）が穿設され且つ１２本のＯ
−リング１６がノズルを取り巻く様に装着されている。FIG. 16 is a sectional view showing another embodiment of the device, and FIG. 17 is a plan view thereof. The nozzle has gas inlet holes 25 (14 holes) corresponding to the number between the layers, and 12 O holes.
- A ring 16 is attached to surround the nozzle.

従って各送入孔２５は夫々完全に独立してその先端を層
間に向けて開口している。第１８図は溶接割れを検知す
る為の説明図で、溶接割れの検知に当っては、まず層間
■に連通されるガス送入孔２５から矢印■′方向洸ガス
を圧入し、層間■及び■からのガスの流出を詞べる。次
に層間■に連通されるガス送入孔２５から矢印■′方向
にガス圧入し、層間０及び■からのガスの流出を調べる
。こうしてガス導入を１つずつ表面側へずらしながら同
様の操作を繰返していくが、これによって溶接割れが順
番に検出されていく。例えば最内層から２番目の積層材
に溶接割れＷｌがあったとすると、矢印Ｏ′に沿って圧
入されたガスが層間＠から層間Ｏに伝わり、矢印０′と
反対方向にガスが詞出して（るので、直ちに検知するこ
とができる。又更にその外層側に溶接割れＷ４があった
とすると、層間■、■、■のいずれか１つに圧入された
ガスが、相互に連通され、矢印■′、■′、０′のいず
れか２つに沿って反対方向に流出していくので、これも
正しく検知することができる。又更に外層側に溶接割れ
Ｗ２があったとすると、層間■又は■のいずれか一方に
圧入されたガスがお互いに連通され、矢印■′又は■′
のいずれかに沿って反対方向に流出してくるので、これ
も容易に検知することができる。Therefore, each inlet hole 25 is completely independent and opens with its tip facing between the layers. Fig. 18 is an explanatory diagram for detecting weld cracks. In detecting weld cracks, gas is first injected in the direction of the arrow ■' from the gas inlet hole 25 communicating with the interlayer ■. ■Describe the gas leaking from. Next, gas is injected under pressure in the direction of arrow {circle around (2)} from the gas inlet hole 25 communicating with interlayer {circle around (2)}, and the outflow of gas from interlayers 0 and {circle around (2)} is examined. In this way, the same operation is repeated while shifting the gas introduction toward the surface one by one, and as a result, weld cracks are sequentially detected. For example, if there is a weld crack Wl in the second laminated material from the innermost layer, the gas injected along the arrow O' will be transmitted from the interlayer @ to the interlayer O, and the gas will come out in the opposite direction to the arrow O' ( Further, if there is a weld crack W4 on the outer layer side, the gas injected into any one of the interlayers ■, ■, ■ will communicate with each other, and the arrow ■' , ■', 0' in the opposite direction, so this can also be detected correctly.Furthermore, if there is a weld crack W2 on the outer layer side, the interlayer ■ or ■ The gas injected into either side is communicated with each other, and the arrow ■′ or ■′
This can also be easily detected as it flows out in the opposite direction along one of the two directions.

上記各説明によって溶接割れの検出方法を明らかにした
が、多層巻圧力容器に取付けるべきノズルの数は、上記
説明から容易に理解される様に１層中の２容接箇所数と
同二・でなければならない。又これ迄に示し念図面では
、例えば第７〜ｌＯ図に見られる様に、裏ビードが内層
側薄板の表面部を溶し込み、層間が中断される場合を示
したが、裏ビードが浅ければ居間はその部分で連続する
ことになる。例えば第１９図において層間■、■′、■
″が完全に連通ぜれているときに、ノズル■だけからガ
スを圧入しておくとガスが層間■′から他の層間■、■
′に逃げて測定ミスを招くことがある。俺って念の為他
のノズル■′からも同圧のガスを圧入しておくことが推
奨される。The method for detecting weld cracks has been clarified through the above explanations, but as can be easily understood from the above explanations, the number of nozzles to be installed in a multi-layer pressure vessel is the same as the number of two-volume contact points in one layer. Must. In addition, the preliminary drawings so far have shown cases where the back bead melts into the surface of the inner layer side thin plate and the interlayer is interrupted, as shown in Figures 7 to 10, for example, but when the back bead is shallow If so, the living room will be continuous in that part. For example, in Fig. 19, the interlayers ■, ■', ■
If the gas is injected only from the nozzle ■ when the two layers are fully connected, the gas will flow from the interlayer ■' to the other interlayers ■, ■.
′ may lead to measurement errors. I recommend injecting gas at the same pressure from other nozzles ■' just in case.

第２０図は第１２．１８図に示した装置を用いて溶接割
れの検知を行なうのに適した配管及び配線図であって２
０２及び２０４〜２１６は夫々３方電磁弁を示し、制御
部２３０の指示によって作動する様に構成されると共に
高圧容器Ｐ（ｃ連接される。そして２１７〜２２９は圧
力変換器であシ。Figure 20 is a piping and wiring diagram suitable for detecting weld cracks using the device shown in Figure 12.18.
Reference numerals 02 and 204 to 216 each indicate a three-way solenoid valve, which is configured to operate according to instructions from a control unit 230 and is connected to a high pressure vessel P (c). Reference numerals 217 to 229 are pressure transducers.

夫々３方電磁弁２０４〜２１６に連通されているから、
例えば第１集団のＨ間■、■、■、■、■へ圧力媒体が
導入されているときには、第２．３集団の層間■、■、
■、■、■、■、■、■からのガス漏れが夫々の圧力変
換器２２２〜２２９を通して比較器群２８１（２８８及
び２３３′によって代表的に示す）に伝達され基準電圧
２３４と比較される。その結果基準電圧を越えるときは
２３２で示すＬＥＤが点灯し、その分布から溶接割れの
位置を判断することができる。同２０１は圧力計であり
、圧力変換器２３５の出力電圧が基準電圧２３７と比較
され（２（６）、基準電圧より低ければＬＥＤ２３８が
点灯する様に構成されて２す、これＫよって最外層へ通
じる溶接割れ（第１１図の０）を検出することができる
。Since they are connected to the three-way solenoid valves 204 to 216, respectively,
For example, when the pressure medium is introduced between the layers of the first group, ■, ■, ■, ■, ■, between the layers of the second and third groups, ■, ■,
Gas leakage from ■, ■, ■, ■, ■, ■ is transmitted through the respective pressure transducers 222-229 to a comparator group 281 (representatively shown by 288 and 233') and compared with a reference voltage 234. . As a result, when the reference voltage is exceeded, the LED indicated by 232 lights up, and the position of the weld crack can be determined from the distribution. Reference numeral 201 is a pressure gauge, and the output voltage of the pressure transducer 235 is compared with a reference voltage 237 (2(6)), and if it is lower than the reference voltage, an LED 238 is turned on. Weld cracks (0 in Figure 11) leading to can be detected.

本発明は以上述べた様に多層巻圧力容器の各層間に通じ
るガス送入孔を設けてガスを圧入し、元圧の変化又は他
の層間からのガスの検出等によって溶接割れの存在を発
見するものであるから、溶接割れの位置や形態等を把握
することができ、多層巻圧力容器の物性伏況を承知し、
且つその安全性について予測をたてることができる様に
なった。As described above, the present invention provides a gas inlet hole that communicates between each layer of a multilayer pressure vessel, injects gas under pressure, and detects the presence of weld cracks by detecting changes in the source pressure or gas from other layers. Therefore, it is possible to grasp the location and form of weld cracks, understand the physical property situation of multilayer pressure vessels,
Moreover, it has become possible to make predictions about its safety.

従って多層巻圧力容器の適用分野を女Ｊむして甚大する
こともできる様になった。Therefore, the field of application of multi-layer pressure vessels can now be greatly expanded.

【図面の簡単な説明】[Brief explanation of drawings]

第１〜６図は多層巻圧力容器の製造手順を示す断面説明
図、第７，８図は本発明の詳細説明第９，１０図は溶接
割れの状況を示す要部断面図、第１１図は溶接割れ検知
の為の説明図、第１２図は本発明において用いるガス圧
入ノズルの平面図、第１３図は使用状態を示す断面説明
図、第１４図は他の実施例に係る使用状■の平面図、第
１５図は溶接割れがある場合の圧力変動グラフ、第１６
図は他の実施例に係る使用状■の断面図、第１７図はそ
の平面図、第１８図は溶接割れ検知の為の説明図、第１
９図は溶接箇所が多い場合のノズル配置側図、第２０図
は溶接割れ検出の為の具体的な配管及び配線側図である
。 ”ｌ　＊　Ｗ２　ｅ　ｗ３１　ｗ４・・・溶接割れ■〜
Ｏ・・・層間 １７〜１９・・・パルプ ２３　　　・・・高圧容器 第１２図 第１４図 第１９図 炉 つ１凸Figures 1 to 6 are cross-sectional explanatory views showing the manufacturing procedure of a multi-layer pressure vessel, Figures 7 and 8 are detailed explanations of the present invention, Figures 9 and 10 are cross-sectional views of main parts showing the situation of weld cracking, and Figure 11. 12 is a plan view of the gas injection nozzle used in the present invention, FIG. 13 is a sectional explanatory view showing the usage condition, and FIG. 14 is the usage condition according to another embodiment. Fig. 15 is a pressure fluctuation graph when there is a weld crack, Fig. 16 is a plan view of
The figure is a cross-sectional view of usage form (■) according to another embodiment, FIG. 17 is a plan view thereof, FIG. 18 is an explanatory diagram for detecting weld cracks,
FIG. 9 is a side view of the nozzle arrangement when there are many welding points, and FIG. 20 is a side view of specific piping and wiring for detecting weld cracks. "l * W2 e w31 w4...Welding crack ■~
O...Interlayers 17-19...Pulp 23...High pressure vessel Figure 12 Figure 14 Figure 19 Furnace 1 convex

Claims (1)

【特許請求の範囲】[Claims] １４１薄板を湾曲させ長手方向ヘシーム溶接することに
よって形成される円筒体が、同・Ｕ状に多数積層されて
なる多層巻圧力容器における溶接割れ検知法であって、
前記圧力容器の軸心と直交する方向に最内層の表面まで
到達する検知穴を掘削し、ある層間に流体を圧入したと
きの元圧の変動又は近接する層間からの前記流体の検出
によって、前記層間に臨設形成されたシーム溶接部の割
れの有無を判定することを特徴とする多層巻圧力容器に
おける溶接割れ検知法。141 A method for detecting weld cracks in a multilayer pressure vessel in which a large number of cylindrical bodies formed by bending thin plates and welding them in a longitudinal direction are laminated in a U-shape, the method comprising:
A detection hole reaching the surface of the innermost layer is drilled in a direction perpendicular to the axis of the pressure vessel, and the fluid is injected between a certain layer and the source pressure changes or the fluid is detected from adjacent layers. A method for detecting weld cracks in a multilayer pressure vessel, characterized by determining the presence or absence of cracks in a seam weld temporarily formed between layers.