JPH0313473B2 - - Google Patents
Info
- Publication number
- JPH0313473B2 JPH0313473B2 JP59161324A JP16132484A JPH0313473B2 JP H0313473 B2 JPH0313473 B2 JP H0313473B2 JP 59161324 A JP59161324 A JP 59161324A JP 16132484 A JP16132484 A JP 16132484A JP H0313473 B2 JPH0313473 B2 JP H0313473B2
- Authority
- JP
- Japan
- Prior art keywords
- bellows
- boundary
- welded
- manufacturing
- skirts
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000004519 manufacturing process Methods 0.000 claims description 17
- 238000000034 method Methods 0.000 claims description 10
- 238000003466 welding Methods 0.000 claims description 10
- 238000007689 inspection Methods 0.000 description 12
- 238000012360 testing method Methods 0.000 description 11
- 230000005855 radiation Effects 0.000 description 5
- 230000035882 stress Effects 0.000 description 5
- 230000007547 defect Effects 0.000 description 4
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910052708 sodium Inorganic materials 0.000 description 3
- 239000011734 sodium Substances 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012530 fluid Substances 0.000 description 2
- 239000011810 insulating material Substances 0.000 description 2
- 238000009659 non-destructive testing Methods 0.000 description 2
- 238000010248 power generation Methods 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 230000008646 thermal stress Effects 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229910001338 liquidmetal Inorganic materials 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 229910001256 stainless steel alloy Inorganic materials 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 230000032258 transport Effects 0.000 description 1
Landscapes
- Joints Allowing Movement (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、原子力発電設備の配管に用いられる
二重ベローズ継手に於けるバウンダリー部の製作
方法の改良に係る。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement in a method for manufacturing a boundary portion in a double bellows joint used for piping of nuclear power generation equipment.
原子力発電設備に用いられる配管、例えば高速
増殖炉の１次冷却系に用いられる配管は、高温の
ナトリウムを輸送することから、その配管系を構
成する配管材料には高温強度の高いステンレス鋼
またはニツケル合金鋼を使用し、外表面は放散熱
量を減少さすために保温材で被覆しているが、か
かる配管は運転中の使用温度が500℃にも達する
ので、配管の熱膨張により熱応力の増大をまね
き、且つ材料の許容応力値も常温に比して低下し
ているので、配管系が破損する危険がある。その
ため熱応力を緩和する方法として複雑な配管引廻
しを必要とし、その結果、配管長が増大し、ハン
ガ、ダンパー数の増加、保温材の増大のみなら
ず、配管系の圧力損失の増大による循環ポンプの
容量増大等をもたらし、プラント建設費の増大を
きたす要因となつている。
Piping used in nuclear power generation equipment, for example, piping used in the primary cooling system of fast breeder reactors, transports high-temperature sodium, so the piping materials that make up the piping system are stainless steel or nickel, which has high high-temperature strength. Alloy steel is used, and the outer surface is covered with a heat insulating material to reduce the amount of heat dissipated, but since the operating temperature of such piping reaches 500℃ during operation, thermal stress increases due to thermal expansion of the piping. In addition, since the allowable stress value of the material is lower than that at room temperature, there is a risk that the piping system will be damaged. Therefore, as a method to alleviate thermal stress, complicated piping is required, resulting in an increase in piping length, an increase in the number of hangers and dampers, an increase in heat insulating material, and an increase in pressure loss in the piping system. This causes an increase in pump capacity, etc., and is a factor that increases plant construction costs.
このようなプラント建設費の増大を抑制するた
めに、配管系の所定の位置に膨張−収縮継手を設
けて熱膨張を吸収し、配管系をコンパクト化する
試みがあるが、原子力プラントでは内部流体漏洩
に対するバウンダリーを形成する必要があり、そ
のため一般に膨張−収縮継手は完全な気密性能を
保つことが可能なベローズ継手が用いられてい
る。このようなベローズ継手はその気密性能に於
いて、万一の損傷に対しても安全性がそこなわれ
ることがないように、二重ベローズを用いること
で、その健全性を保持する構成としている。例え
ばFBRでは、冷却材に液体金属ナトリウムを用
いていることから、万一バウンダリーが破損し、
ナトリウムの外部流出事故が起ると、空気中の酸
素により激しい酸化反応が起り、火災の原因とな
る。そのため第１図に示すようにバウンダリーベ
ローズ１とバツクアツプベローズ２とを二重にし
て同心円状に設置することで、仮にバウンダリー
ベローズ１が破損しても、バツクアツプベローズ
２の働きで冷却材の外部流出を防止するととも
に、バウンダリーベローズ１とバツクアツプベロ
ーズ２との間に設けられたリーク検出装置１１に
よつて、直ちにバウンダリーベローズ１の破損を
検知して、プラントの連鎖事故の発生を未然に防
止し、プラントの安全性を保持している。 In order to suppress this increase in plant construction costs, attempts have been made to install expansion-contraction joints at predetermined positions in the piping system to absorb thermal expansion and make the piping system more compact. It is necessary to form a boundary against leakage, and for this reason, bellows joints are generally used as expansion-deflation joints, which can maintain complete airtight performance. This type of bellows joint uses double bellows to maintain its airtightness and safety even in the unlikely event of damage. . For example, in FBR, liquid metal sodium is used as a coolant, so in the unlikely event that the boundary is damaged,
If a sodium leakage accident occurs, a violent oxidation reaction will occur due to oxygen in the air, causing a fire. Therefore, by doubling the boundary bellows 1 and back-up bellows 2 and installing them concentrically as shown in Figure 1, even if the boundary bellows 1 is damaged, the back-up bellows 2 will cool it down. In addition to preventing materials from flowing out, the leak detection device 11 installed between the boundary bellows 1 and the backup bellows 2 immediately detects damage to the boundary bellows 1 and prevents chain accidents in the plant. This prevents occurrences and maintains plant safety.
第１図中、３，４はベローズ１，２の両端に溶
接にて取付けられたスカートである。６，６′は
フロースリーブで、バウンダリーベローズ１の内
側に位置し、その一端がダクト７及び７′に一体
となるように溶接して取付けられており、他端は
相互に摺設して取付けられて、ベローズ継手内の
流体の流動抵抗の低減と流力振動を防止する役割
を果たしている。ダクト７及び７′はスカート３，
４に一体となるよう突合せ溶接で接続されてい
る。相対向する二つのシエル８と８′はダクト７，
７′に接続されている。又、このシエル８，８′
は、接続リング９を介してピン１０によつて回転
可能に接合されている。 In FIG. 1, 3 and 4 are skirts attached to both ends of the bellows 1 and 2 by welding. Reference numerals 6 and 6' designate flow sleeves located inside the boundary bellows 1, one end of which is integrally welded to the ducts 7 and 7', and the other ends slidably attached to each other. It plays the role of reducing fluid flow resistance within the bellows joint and preventing fluid vibration. The ducts 7 and 7' have skirts 3,
4 are connected by butt welding so that they become one piece. The two opposing shells 8 and 8' are the duct 7,
7'. Also, this Ciel 8,8'
are rotatably joined by a pin 10 via a connecting ring 9.
このような原子力プラントに用いられる二重ベ
ローズ継手は、製作中の品質管理はもちろん製作
法に於いても、充分な試験・検査が必要であり、
特に溶接部の検査は非破壊検査が要求される。非
破壊検査は体積検査が必要であるが、体積検査の
中でも超音波探傷試験はステンレス鋼、ニツケル
合金鋼には適用出来ないので、放射線検査を行う
ことが必要となる。 The double bellows joints used in such nuclear power plants require sufficient testing and inspection not only for quality control during manufacturing but also for the manufacturing method.
In particular, non-destructive testing is required to inspect welded parts. Non-destructive testing requires volumetric testing, but even among volumetric testing, ultrasonic flaw detection cannot be applied to stainless steel and nickel alloy steel, so radiation testing is required.
ところで、上記ベローズ継手は、バウンダリー
部を形成するために、バウンダリーベローズ１と
バツクアツプベローズ２とを二重にして、これら
のベローズの両端にスカート３，４を溶接する手
順となつていることから、突合せ溶接が不可能と
なり、従つて、放射線検査も実施不能となる個所
が出てきた。即ち、第２図に示すように、バウン
ダリーベローズ１のスカート３，４をＡ，Ｂの個
所で突合せ溶接し、放射線検査等の所定の試験・
検査を終了したのち、あらかじめバツクアツプベ
ローズ２と単管５，６とを溶接し試験・検査の完
了したバツクアツプベローズ部品を、スカート３
側からスカート３にかぶせるように差し込んで、
バウンダリーベローズ１の外周側に嵌装し、スカ
ート３，４とＥ，E′の箇所で隅肉溶接するため、
該溶接部の放射線検査を実施することができなか
つた。また曲り部での隅肉溶接であるため溶接部
の欠陥の存在確率が高く、且つ曲り部での応力集
中が大きく、健全性、信頼性に欠ける。
By the way, the above-mentioned bellows joint has a procedure in which the boundary bellows 1 and the back-up bellows 2 are doubled to form a boundary part, and skirts 3 and 4 are welded to both ends of these bellows. As a result, butt welding has become impossible, and therefore radiographic inspection has become impossible in some areas. That is, as shown in FIG. 2, the skirts 3 and 4 of the boundary bellows 1 are butt-welded at points A and B, and subjected to a predetermined test such as a radiation inspection.
After completing the inspection, weld the back-up bellows 2 and the single pipes 5 and 6 in advance, and attach the back-up bellows parts that have been tested and inspected to the skirt 3.
Insert it from the side so that it covers skirt 3,
In order to fit it on the outer circumferential side of the boundary bellows 1 and perform fillet welding to the skirts 3 and 4 at points E and E',
It was not possible to carry out a radiological inspection of the weld. Furthermore, since fillet welding is performed at a bend, there is a high probability of defects in the weld, and stress concentration at the bend is large, resulting in poor soundness and reliability.
そこで本発明は、製作時溶接部の放射線検査が
可能で、溶接部の欠陥の存在確率が低く、曲り部
での応力集中が小さく、健全性に優れ、信頼性の
高いベローズ継手に於けるバウンダリー部を製作
する方法を提供しようとするものである。 Therefore, the present invention enables radiation inspection of welded parts during manufacturing, has a low probability of existence of defects in welded parts, has low stress concentration at bent parts, has excellent soundness, and has high reliability in bellows joints. The aim is to provide a method for manufacturing parts.
上記課題を解決するための本発明の二重ベロー
ズ継手に於けるバウンダリー部の製作方法は、バ
ウンダリーベローズの外周側にバツクアツプベロ
ーズを同心円状に配設してなる二重ベローズ継手
に於けるバウンダリー部を製作するに於いて、バ
ウンダリーベローズとバツクアツプベローズの両
端に夫々スカートを突き合わせ溶接にて接続し、
バウンダリーベローズの外周側にバツクアツプベ
ローズを同心円状に嵌装セツトし、夫々の両端の
スカート同志を円錐部のほぼ中間で突き合わせ溶
接して、バウンダリーベローズとバツクアツプベ
ローズとの間にバウンダリー部を製作することを
特徴とするものである。
A method for manufacturing a boundary portion in a double bellows joint of the present invention to solve the above problems is a method for manufacturing a boundary portion in a double bellows joint in which a back-up bellows is arranged concentrically on the outer peripheral side of a boundary bellows. When manufacturing the boundary part, connect skirts to both ends of the boundary bellows and back-up bellows by butt welding,
A back-up bellows is fitted and set concentrically on the outer circumferential side of the boundary bellows, and the skirts at both ends are butt-welded approximately in the middle of the conical part to form a boundary part between the boundary bellows and the back-up bellows. It is characterized by producing.
上記のように本発明の二重ベローズ継手におけ
るバウンダリー部の製作方法によれば、全ての溶
接線が、突き合わせ溶接となるので、その溶接線
の外表面に放射線透過試験フイルム、透過度計及
び線源が一直線上になるように配することによ
り、放射線透過試験が可能となる。また、バウン
ダリーベローズの両端に突き合わせ溶接したスカ
ートと、バツクアツプベローズの両端に突き合わ
せ溶接したスカートとを円錐部で突き合わせ溶接
するので、該溶接部の欠陥の存在確率が低くな
り、スカートの曲り部での応力集中が小さくな
る。従つて、健全性に優れた信頼性の高い二重ベ
ローズ継手のバウンダリー部が得られる。
As described above, according to the manufacturing method of the boundary part in the double bellows joint of the present invention, all the weld lines are butt welded, so the outer surface of the weld line is covered with a radiographic test film, a penetrameter, and a wire. Placing the sources in a straight line allows radiographic testing. In addition, since the skirt butt-welded to both ends of the boundary bellows and the skirt welded butt-welded to both ends of the back-up bellows are butt-welded at the conical part, the probability of defects in the welding part is low, and the skirt is butt-welded to both ends of the back-up bellows. The stress concentration at is reduced. Therefore, a boundary portion of a double bellows joint with excellent integrity and high reliability can be obtained.
本発明の二重ベローズ継手に於けるバウンダリ
ー部の製作方法の一実施例を図によつて説明する
と、第３図ａに示すように、最初にバウンダリー
ベローズ１にスカート３及び３′をＡ，Ｂの個所
で突合せ溶接して、必要な所定の試験・検査を実
施する。検査合格後、あらかじめ用意してある第
３図ｂにバツクアツプベローズ取付け用スカート
３′，４′とバツクベローズ２とをＤ及びＣの個所
で溶接し、所定の試験・検査が完了し合格してい
るバツクアツプベローズ部品を、第３図ｃに示す
如くスカート３の方向より差し込み、バウンダリ
ーベローズ１の外周側に同心円状に嵌装セツトし
て、円錐部のＥ，E′の個所でスカート３と３′、
スカート４と４′とを突き合せ溶接し、所定の試
験・検査を終了してバウンダリーベローズ部の製
作を完了する。
One embodiment of the method for manufacturing the boundary portion in the double bellows joint of the present invention will be explained with reference to the drawings.As shown in FIG. , B butt weld and carry out the necessary prescribed tests and inspections. After passing the inspection, the back up bellows mounting skirts 3', 4' and back bellows 2 are welded at points D and C as shown in Figure 3b prepared in advance, and the prescribed tests and inspections are completed and passed. Insert the back-up bellows parts from the direction of the skirt 3 as shown in Fig. 3c, fit them concentrically around the outer circumference of the boundary bellows 1, and close the skirt at points E and E' of the conical part. 3 and 3',
The skirts 4 and 4' are butt welded, and after completing the prescribed tests and inspections, the production of the boundary bellows portion is completed.
このようにして、二重ベローズ継手の最も重要
なバウンダリー部の製作に於いて、全ての溶接線
が突合せ溶接となることから必要な試験・検査は
全ての実施可能となり、特にこれまで不可能であ
つた放射線検査は、突き合わせ溶接部の外表面に
放射線透過フイルム、透過度計及び線源が一直線
上になるように配することによつて、放射線透過
試験を容易に実施でき、その検査が可能となつ
た。 In this way, in the production of the most important boundary part of a double bellows joint, all the weld lines are butt welded, making it possible to carry out all the necessary tests and inspections, which were previously impossible. Atsuta radiographic inspection can be easily carried out by placing a radiographic film, a penetrameter, and a radiation source in a straight line on the outer surface of the butt weld. It became.
以上詳述したとおり本発明の二重ベローズ継手
に於けるバウンダリー部の製作方法は、バウンダ
リーベローズとバツクアツプベローズとの両端に
夫々スカートを突き合わせ溶接にて接続し、バウ
ンダリーベローズの外周側にバツクアツプベロー
ズを同心円状に嵌装セツトし、夫々の両端のスカ
ート同志を円錐部のほぼ中間で突合せ溶接するの
で、全ての溶接線が放射線検査の可能な溶接構造
となる。また円錐部での突き合わせ溶接により、
溶接部の欠陥の存在確率が低くなり、スカートの
曲り部での応力集中が小さくなる。従つて、健全
性に優れ、信頼性の高い二重ベローズ継手のバウ
ンダリー部が得られる。
As detailed above, the method for manufacturing the boundary part in the double bellows joint of the present invention is to connect skirts to both ends of the boundary bellows and back-up bellows by butt welding, and Since the back-up bellows are fitted and set concentrically and the skirts at both ends are butt welded approximately in the middle of the conical part, all weld lines have a welded structure that can be inspected by radiation. In addition, by butt welding at the conical part,
The probability of defects in the weld is lowered, and the stress concentration at the bend in the skirt is reduced. Therefore, a boundary portion of a double bellows joint with excellent soundness and high reliability can be obtained.
第１図は従来の二重ベローズ継手の断面図、第
２図は従来の二重ベローズ継手のバウンダリー部
の構造断面図、第３図ａ，ｂ，ｃは本発明の二重
ベローズ継手に於けるバウンダリー部の製作方法
の工程を示す図である。
１……バウンダリーベローズ、２……バツクア
ツプベローズ、３，４……スカート、３′，４′…
…バツクアツプベローズ取付用スカート。
Fig. 1 is a sectional view of a conventional double bellows joint, Fig. 2 is a structural sectional view of the boundary part of a conventional double bellows joint, and Figs. 3a, b, and c are cross-sectional views of the double bellows joint of the present invention. It is a figure which shows the process of the manufacturing method of the boundary part which can be carried out. 1...Boundary bellows, 2...Back up bellows, 3, 4...Skirt, 3', 4'...
...Skirt for mounting back-up bellows.
Claims (1)
プベローズを同心円状に配設してなる二重ベロー
ズ継手に於けるバウンダリー部を製作するに於い
て、バウンダリーベローズとバツクアツプベロー
ズの両端に夫々スカートを突き合わせ溶接にて接
続し、バウンダリーベローズの外周側にバツクア
ツプベローズを同心円状に嵌装セツトし、夫々の
両端のスカート同志を円錐部のほぼ中間で突き合
わせ溶接して、バウンダリーベローズとバツクア
ツプベローズとの間にバウンダリー部を製作する
ことを特徴とする二重ベローズ継手に於けるバウ
ンダリー部の製作方法。1. When manufacturing the boundary part of a double bellows joint in which back-up bellows are arranged concentrically around the outer circumference of a boundary bellows, skirts are butted against both ends of the boundary bellows and back-up bellows, respectively. The boundary bellows and back up bellows are connected by welding, and the back up bellows are fitted and set concentrically on the outer circumferential side of the boundary bellows, and the skirts at both ends of each are butt welded approximately in the middle of the conical part to connect the boundary bellows and back up bellows. A method for manufacturing a boundary part in a double bellows joint, characterized by manufacturing a boundary part between.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16132484A JPS6138290A (en) | 1984-07-31 | 1984-07-31 | Double bellows joint |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16132484A JPS6138290A (en) | 1984-07-31 | 1984-07-31 | Double bellows joint |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6138290A JPS6138290A (en) | 1986-02-24 |
| JPH0313473B2 true JPH0313473B2 (en) | 1991-02-22 |
Family
ID=15732923
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16132484A Granted JPS6138290A (en) | 1984-07-31 | 1984-07-31 | Double bellows joint |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6138290A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008151588A (en) * | 2006-12-15 | 2008-07-03 | Idemitsu Eng Co Ltd | Flaw evaluation method of two-layered bellows and eddy current flaw detector used therein |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5962791A (en) * | 1982-09-30 | 1984-04-10 | 株式会社東芝 | Expansion joint device for piping |
-
1984
- 1984-07-31 JP JP16132484A patent/JPS6138290A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5962791A (en) * | 1982-09-30 | 1984-04-10 | 株式会社東芝 | Expansion joint device for piping |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6138290A (en) | 1986-02-24 |
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