JPH06170468A - Method for joining zirconium alloy tube and martensitic stainless steel tube - Google Patents
Method for joining zirconium alloy tube and martensitic stainless steel tubeInfo
- Publication number
- JPH06170468A JPH06170468A JP32640592A JP32640592A JPH06170468A JP H06170468 A JPH06170468 A JP H06170468A JP 32640592 A JP32640592 A JP 32640592A JP 32640592 A JP32640592 A JP 32640592A JP H06170468 A JPH06170468 A JP H06170468A
- Authority
- JP
- Japan
- Prior art keywords
- zirconium
- tube
- stainless steel
- martensitic stainless
- zirconium alloy
- 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.)
- Pending
Links
Landscapes
- Heat Treatment Of Articles (AREA)
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は、ジルコニウムあるいは
ジルコニウム合金からなる管とマルテンサイト系ステン
レス鋼管からなる延長管の機械的接続方法に係り、接続
部におけるジルコニウムあるいはジルコニウム合金から
なる管の高温水に依る水素吸収を抑制するために好適な
マルテンサイト系ステンレス鋼管とジルコニウム及びジ
ルコニウム合金の圧力管の接続方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for mechanically connecting a pipe made of zirconium or a zirconium alloy and an extension pipe made of a martensitic stainless steel pipe to a high temperature water of a pipe made of zirconium or a zirconium alloy at a connecting portion. The present invention relates to a method for connecting a martensitic stainless steel pipe and a pressure pipe made of zirconium or a zirconium alloy suitable for suppressing hydrogen absorption.
【0002】[0002]
【従来の技術】ジルコニウムあるいはジルコニウム合金
からなる管と異種金属であるステンレス鋼管との接続
は、溶接による冶金的な接合が困難であるため、特願昭
59−6751号及び特願昭63−279250号明細書に記載のよう
に、拡管させて機械的に接合する方式となっている。2. Description of the Related Art A connection between a tube made of zirconium or a zirconium alloy and a stainless steel tube, which is a dissimilar metal, is difficult to perform metallurgically by welding.
As described in the specifications of No. 59-6751 and Japanese Patent Application No. 63-279250, the pipe is expanded and mechanically joined.
【0003】しかし、従来技術のジルコニウム合金から
なる管と異種金属であるステンレス鋼管との接続面で
は、腐食電位差によりすき間腐食を起こし、発生した水
素がジルコニウム合金管に吸収されやすい。その結果、
ジルコニウム合金管は、水素濃度の増加に伴い、脆化す
ることが危惧される。However, crevice corrosion occurs at the connection surface between the conventional tube made of a zirconium alloy and a stainless steel tube which is a dissimilar metal, and the generated hydrogen is easily absorbed by the zirconium alloy tube. as a result,
It is feared that the zirconium alloy tube becomes brittle as the hydrogen concentration increases.
【0004】[0004]
【発明が解決しようとする課題】上記従来技術は、ジル
コニウム合金とステンレス鋼との異種金属がすき間を構
成する接続部で、電気化学的にステンレス鋼が最も卑電
位であるためにステンレス鋼が犠牲陽極となりアノード
溶解して腐食損傷を生じ、かつ、発生した水素がジルコ
ニウムに吸収されることが危惧される問題があった。SUMMARY OF THE INVENTION The above-mentioned prior art is a sacrifice of stainless steel because the dissimilar metal of zirconium alloy and stainless steel constitutes a gap, and electrochemically stainless steel has the most base potential. There is a problem that it becomes an anode and the anode dissolves to cause corrosion damage, and that the generated hydrogen is absorbed by zirconium.
【0005】本発明の目的は、マルテンサイト系ステン
レス鋼及びジルコニウム合金のすき間腐食による損傷を
防止することにある。An object of the present invention is to prevent martensitic stainless steel and zirconium alloy from being damaged by crevice corrosion.
【0006】[0006]
【課題を解決するための手段】上記目的を達成するた
め、マルテンサイト系ステンレス鋼とジルコニウム及び
ジルコニウム合金との接触部で、拡管による接合を行う
前に、ジルコニウム及びジルコニウム合金と接触するマ
ルテンサイト系ステンレス鋼側の表面部を高温大気中に
保持させて、高温酸化皮膜を形成する。In order to achieve the above object, at the contact portion between martensitic stainless steel and zirconium and zirconium alloy, the martensitic stainless steel that comes into contact with zirconium and zirconium alloy before joining by expansion is performed. The surface portion on the stainless steel side is kept in a high temperature atmosphere to form a high temperature oxide film.
【0007】[0007]
【作用】マルテンサイト系ステンレス鋼表面部の高温加
熱により表面改質を行うものである。すなわち、高温加
熱処理によりマルテンサイト系ステンレス鋼表面部に
は、高温酸化皮膜が形成される。この結果、マルテンサ
イト系ステンレス鋼表面部は顕著な耐食性をもつように
なるので、ジルコニウム及びジルコニウム合金との接触
腐食の抑制に効果がある。したがって、200℃から3
50℃の高温水に曝露される場合、異種金属接蝕腐食に
よりジルコニウム及びジルコニウム合金が水素を吸収す
ることを抑制することができる。[Function] The surface of the martensitic stainless steel is heated at a high temperature for surface modification. That is, a high temperature oxide film is formed on the surface of the martensitic stainless steel by the high temperature heat treatment. As a result, the surface of the martensitic stainless steel has remarkable corrosion resistance, which is effective in suppressing contact corrosion with zirconium and zirconium alloys. Therefore, from 200 ℃ to 3
When exposed to high temperature water of 50 ° C., it is possible to suppress zirconium and the zirconium alloy from absorbing hydrogen due to corrosion of dissimilar metals.
【0008】[0008]
【実施例】以下、図面を参照しながら本発明を説明す
る。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.
【0009】図1は、本発明によるジルコニウム−ニオ
ブ合金からなる管とマルテンサイト系ステンレス鋼管の
接続前の断面図であり、ジルコニウム−ニオブ合金管1
の端面の内面には適度なテーパを付け、マルテンサイト
系ステンレス鋼管の端部は、ジルコニウム−ニオブ合金
管1の内径よりも大きい外径のテーパを有する内スリー
ブ2が機械加工され、さらに、内スリーブ2のテーパ部
の表面には予め573K(300℃)の高温大気中で1
0時間保持させて形成された高温酸化皮膜4が付加させ
てある。なお、ジルコニウム−ニオブ合金管1には内ス
リーブ2のテーパ部と逆向きのテーパ部を有する外リン
グ3が予め挿入してある。なお、外リング3のテーパ部
の内径は内スリーブ2の外径にジルコニウム−ニオブ合
金管1の肉厚の2倍より若干小さめの値を加えたもので
ある。ジルコニウム−ニオブ合金管1を内スリーブ2の
テーパ部に沿って、荷重を加えながら、かつ、ジルコニ
ウム−ニオブ合金管1を拡管させて挿入した状況が図2
である。ジルコニウム−ニオブ合金管1を拡管させつつ
内スリーブ2に挿入を完了した後に、拡管されたジルコ
ニウム−ニオブ合金管1の外面より、目視による外観検
査および超音波探傷などによる非破壊検査を実施し、ジ
ルコニウム−ニオブ合金管1の拡管部に有害な欠陥がな
いことを確認した後に、図3に示すように、外リング3
をジルコニウム−ニオブ合金管1の拡管部の外周面を圧
着させながら嵌め込む。外リング3は、内スリーブ2と
ねじ締結されるようになっている。FIG. 1 is a sectional view of a zirconium-niobium alloy pipe according to the present invention and a martensitic stainless steel pipe before being connected.
An inner surface of the end surface of the martensitic stainless steel pipe is machined with an inner sleeve 2 having an outer diameter larger than the inner diameter of the zirconium-niobium alloy pipe 1. The surface of the taper portion of the sleeve 2 is preliminarily 1
A high temperature oxide film 4 formed by holding for 0 hour is added. The zirconium-niobium alloy tube 1 is preliminarily inserted with an outer ring 3 having a tapered portion opposite to the tapered portion of the inner sleeve 2. The inner diameter of the tapered portion of the outer ring 3 is the outer diameter of the inner sleeve 2 plus a value slightly smaller than twice the wall thickness of the zirconium-niobium alloy tube 1. The state in which the zirconium-niobium alloy tube 1 is inserted along the tapered portion of the inner sleeve 2 while applying a load and the zirconium-niobium alloy tube 1 is expanded is shown in FIG.
Is. After completing the insertion into the inner sleeve 2 while expanding the zirconium-niobium alloy tube 1, a non-destructive inspection such as visual inspection and ultrasonic flaw detection is performed from the outer surface of the expanded zirconium-niobium alloy tube 1. After confirming that the expanded part of the zirconium-niobium alloy tube 1 has no harmful defects, as shown in FIG.
The zirconium-niobium alloy tube 1 is fitted while pressing the outer peripheral surface of the expanded portion. The outer ring 3 is screwed to the inner sleeve 2.
【0010】接合後、561K(288℃),7.8M
Pa の高温水中に浸漬し、ジルコニウム−ニオブ合金
管の水素濃度増加量と時間の関係を図4に示す。本実施
例のジルコニウム−ニオブ合金管の水素濃度増加量は、
従来技術に比べて約1/5と低いことが明らかである。
なお、本実施例のジルコニウム−ニオブ合金管の初期の
含有水素濃度は、約10ppm であった。After joining, 561K (288 ° C), 7.8M
FIG. 4 shows the relationship between the hydrogen concentration increase amount and time of the zirconium-niobium alloy tube immersed in high-temperature water of Pa 2. The hydrogen concentration increase amount of the zirconium-niobium alloy tube of this example is
It is clear that it is as low as about 1/5 as compared with the conventional technique.
The initial hydrogen content of the zirconium-niobium alloy tube of this example was about 10 ppm.
【0011】本実施例によれば、ジルコニウム−ニオブ
合金管と接触する内スリーブ表面部は顕著な耐食性をも
つようになるので、接触腐食の抑制に効果がある。した
がって、200℃から350℃の高温水に曝露される場
合、異種金属接蝕腐食によりジルコニウム及びジルコニ
ウム合金が損傷することを抑制することができる。すな
わち、ジルコニウム及びジルコニウム合金管の水素吸収
による脆化を少なくする効果がある。According to this embodiment, the surface of the inner sleeve which comes into contact with the zirconium-niobium alloy tube has remarkable corrosion resistance, which is effective in suppressing contact corrosion. Therefore, when exposed to high temperature water of 200 ° C. to 350 ° C., damage to zirconium and zirconium alloy due to corrosion of dissimilar metals can be suppressed. That is, there is an effect of reducing embrittlement of zirconium and a zirconium alloy tube due to hydrogen absorption.
【0012】[0012]
【発明の効果】本発明によれば、ジルコニウム及びジル
コニウム合金管とマルテンサイト系ステンレス鋼の異種
金属接合部のすき間が200℃から350℃の高温水に
曝露される場合、マルテンサイト系ステンレス鋼とジル
コニウム及びジルコニウム合金圧力管がすき間腐食によ
り損傷を抑制することができる。According to the present invention, when the gap between the dissimilar metal joint between the zirconium and zirconium alloy pipe and the martensitic stainless steel is exposed to high temperature water of 200 ° C to 350 ° C, the martensitic stainless steel is Damage to the zirconium and zirconium alloy pressure pipes due to crevice corrosion can be suppressed.
【図1】本発明の一実施例を示すジルコニウム及びジル
コニウム合金管とマルテンサイト系ステンレス鋼管との
接合前の断面図。FIG. 1 is a cross-sectional view of a zirconium or zirconium alloy pipe and a martensitic stainless steel pipe before joining, showing an embodiment of the present invention.
【図2】本発明による接合方法を説明する断面図。FIG. 2 is a sectional view illustrating a joining method according to the present invention.
【図3】本発明によるジルコニウム及びジルコニウム合
金管とマルテンサイト系ステンレス鋼管との接合を示す
断面図。FIG. 3 is a cross-sectional view showing the joining of zirconium and a zirconium alloy tube and a martensitic stainless steel tube according to the present invention.
【図4】従来技術と本発明によるジルコニウム合金管の
水素吸収特性を示す特性図。FIG. 4 is a characteristic diagram showing hydrogen absorption characteristics of a zirconium alloy tube according to the related art and the present invention.
1…ジルコニウム合金管、2…マルテンサイト系ステン
レス鋼管内スリーブ、3…外リング、4…マルテンサイ
ト系ステンレス鋼管の高温酸化皮膜。1 ... Zirconium alloy tube, 2 ... Martensitic stainless steel tube inner sleeve, 3 ... Outer ring, 4 ... High temperature oxide film of martensitic stainless steel tube.
Claims (1)
らなる管の管端に、マルテンサイト系ステンレス鋼から
なる管状部材の端部を挿入し、内側から拡管で接続する
方法において、前記マルテンサイト系ステンレス鋼管の
端部の内外表面を250℃以上に加熱し、酸化皮膜を生
成させてから、ジルコニウムあるいはジルコニウム合金
管の内面に挿入することを特徴とするジルコニウム合金
管とマルテンサイト系ステンレス鋼管との接合方法。1. A method of inserting an end of a tubular member made of martensitic stainless steel into a pipe end of a pipe made of zirconium or a zirconium alloy and connecting from the inside by expanding the pipe, wherein the end of the martensitic stainless steel pipe is A method for joining a zirconium alloy tube and a martensitic stainless steel tube, which comprises heating the inner and outer surfaces of the part to 250 ° C. or higher to form an oxide film and then inserting the oxide film into the inner surface of the zirconium or zirconium alloy tube.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP32640592A JPH06170468A (en) | 1992-12-07 | 1992-12-07 | Method for joining zirconium alloy tube and martensitic stainless steel tube |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP32640592A JPH06170468A (en) | 1992-12-07 | 1992-12-07 | Method for joining zirconium alloy tube and martensitic stainless steel tube |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH06170468A true JPH06170468A (en) | 1994-06-21 |
Family
ID=18187428
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP32640592A Pending JPH06170468A (en) | 1992-12-07 | 1992-12-07 | Method for joining zirconium alloy tube and martensitic stainless steel tube |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH06170468A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5864938A (en) * | 1994-09-15 | 1999-02-02 | Nellcor Puritan Bennett, Inc. | Assembly of semi-disposable ventilator breathing circuit tubing with releasable coupling |
-
1992
- 1992-12-07 JP JP32640592A patent/JPH06170468A/en active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5864938A (en) * | 1994-09-15 | 1999-02-02 | Nellcor Puritan Bennett, Inc. | Assembly of semi-disposable ventilator breathing circuit tubing with releasable coupling |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4556240A (en) | Corrosion-resistant, double-wall pipe structures | |
JPH06170468A (en) | Method for joining zirconium alloy tube and martensitic stainless steel tube | |
US3602978A (en) | Method of forming bimetallic transition joints | |
JPS61142025A (en) | Preparation of clamp made of shape memory alloy | |
JP2006284169A (en) | Evaporation bank tapered tubing of co-extrusion molding | |
JPH07328853A (en) | Joining method of zirconium alloy pipe to stainless steel pipe | |
JP2005088048A (en) | Flange for absorbing welding deformation for piping joint, and piping joint using the same | |
JPH05157890A (en) | Joining method of pressure pipe and martensite group stainless steel pipe | |
JPH11290939A (en) | Manufacture of long double metallic tube | |
JPH0938734A (en) | Method for joining zirconium or zirconium alloy-made tube and stainless steel tube | |
JPH05172989A (en) | Connection method for stainless steel pipe and zirconium alloy pipe | |
JP3410814B2 (en) | Different diameter pipe joint device | |
JPS5820389A (en) | Structure of friction welded joint of pipe | |
JPS6024234A (en) | Joint structure of pipe ends | |
JPH08152290A (en) | Method for welding different metals and welded structure thereof | |
JP2004298942A (en) | Welding method for improving welding fatigue strength | |
JPH0645068B2 (en) | Dissimilar material welded joint structure | |
JP2004291044A (en) | Structure and method of joining stainless steel pipe and aluminum alloy pipe | |
JPH08197162A (en) | Rolled joint method for tube | |
JPH04123866A (en) | Joint of zirconium alloy tube | |
JP4028684B2 (en) | Steel pipe joint structure | |
JP2000071029A (en) | Manufacture of long length double metallic pipe | |
JPH07119885A (en) | Repairing method of container penetrating piping | |
JPS5855189A (en) | Welded joint structure of concentric circle pipe having different diameters | |
JPS63123591A (en) | Welding method for pipe joint part |