JPH06246372A - Manufacture of double metallic tube - Google Patents

Abstract

PURPOSE:To improve workability in the manufacture of a double metallic tube and to facilitate the inspection of joined parts by reducing the projection of an extension external tube and repeating the joining of an extension internal tube, the expansion of tube, and the joining of the extension external tube. CONSTITUTION:When an internal tube 2 is expanded while the expansion of the diameter of its projected part 2a is controlled, most parts except the vicinity of the projected part 2a are closely adhered. In the state where the tip end of the internal tube 2 is joined with the extension internal tube, the projected part 2a of the internal tube 2 is not expanded in diameter, and consequently. a working space is secured in the case of joining the extension external tube to the external tube 1. By reducing the projection of the extension external tube and repeating the extension of the internal tube 2, the expansion of the tube, and the extension of the external tube 1, the freedom of the extending dimension of a double metallic tube is generated. Also, at the time of expanding the internal tube 2 and the external tube 1, by forming a space between the external tube 1 and the extension external tube, the working space is secured to improve the workability in the manufacturing, and the inspection, etc., of the joined parts is easily implemented.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は、二重金属管の製造方法
に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a double metal tube.

【０００２】[0002]

【従来の技術】大型の蒸気発生器や熱交換器に使用され
る伝熱管には、耐食性や耐圧性等の信頼性を向上させる
目的で、図６に示すような二重金属管が使用される。図
６において、符号１は外管、２は内管、Ｇは環状間隙で
ある。このような伝熱管では、外管１の外表面が高温流
体に接触し、内管２の内部に水等の被加熱流体が流さ
れ、環状間隙Ｇは、外管１及び内管２の漏洩検出路等に
利用される。2. Description of the Related Art As a heat transfer tube used in a large steam generator or a heat exchanger, a double metal tube as shown in FIG. 6 is used for the purpose of improving reliability such as corrosion resistance and pressure resistance. . In FIG. 6, reference numeral 1 is an outer tube, 2 is an inner tube, and G is an annular gap. In such a heat transfer tube, the outer surface of the outer tube 1 comes into contact with the high-temperature fluid, a heated fluid such as water flows in the inner tube 2, and the annular gap G is leaked from the outer tube 1 and the inner tube 2. It is used as a detection path.

【０００３】従来、上記伝熱管の製造に係る技術とし
て、特開昭６３−１９９０１７号公報（蒸気発生器伝熱
管の製造方法）が提案されている。この製造方法では、
複数の管を同心円状に組み合わせておいて、中心に入れ
たプラグの引き抜きと外側のダイスによる外径抑制とに
よって、複数の管を相互に密着状態に導くようにしてい
る。Conventionally, Japanese Patent Laid-Open No. 63-199017 (method for manufacturing a steam generator heat transfer tube) has been proposed as a technique for manufacturing the heat transfer tube. In this manufacturing method,
A plurality of tubes are concentrically combined, and the plurality of tubes are brought into close contact with each other by pulling out a plug inserted in the center and suppressing an outer diameter by an outer die.

【０００４】[0004]

【発明が解決しようとする課題】しかし、伝熱管の引き
抜き加工の際には、金属管の伸び量が加工の進行ととも
に積算されるとともに、長尺状態の伝熱管を得ようとす
ると、プラグ及びダイスの位置関係の設定が困難なもの
となるために、高度の技術及び熟練に加えて多大の労力
が必要になる。However, when the heat transfer tube is drawn, the elongation of the metal tube is integrated with the progress of processing, and when the heat transfer tube in a long state is to be obtained, the plug and Since it is difficult to set the positional relationship of the dice, a great deal of labor is required in addition to high skill and skill.

【０００５】本発明は、かかる事情に鑑みてなされたも
ので、二重金属管製造時の作業性を向上させること、
金属管の接合部分の検査を容易にすること、二重金
属管相互の接合を抑制すること目的としている。The present invention has been made in view of the above circumstances, and is to improve workability in manufacturing a double metal tube,
The purpose is to facilitate the inspection of the joint portion of the metal pipe and to suppress the joint between the double metal pipes.

【０００６】[0006]

【課題を解決するための手段】外管に先端を突出させた
状態の内管を挿入する工程と、内管の突出部分の寸法変
化を抑制しながら内管を拡管して外管に密着させる工程
と、内管の突出部分の先端に延長内管を接合する工程
と、外管に延長内管よりも突出量の少ない延長外管を接
合する工程とが繰り返される構成の二重金属管の製造方
法を採用している。[MEANS FOR SOLVING THE PROBLEMS] A step of inserting an inner tube having a protruding end into the outer tube, and expanding the inner tube while closely controlling the dimensional change of a protruding portion of the inner tube to bring the inner tube into close contact with the outer tube. Manufacture of a double metal pipe having a structure in which a step, a step of joining an extension inner tube to the tip of a protruding portion of the inner tube, and a step of joining an extension outer tube having a smaller amount of protrusion than the extension inner tube to the outer tube are repeated The method is adopted.

【０００７】[0007]

【作用】突出部分の拡径を抑制しながら内管を拡管する
と、突出部分近傍を除く大部分が密着状態となる。内管
の先端に延長内管を接合した状態にあっては、内管の突
出部分が拡径されていないため、外管に延長外管を接合
する際の作業スペースが確保される。延長外管の突出量
を少なくしておいて、内管の延長、拡管、外管の延長を
繰り返すことにより、二重金属管の延長寸法の自由性が
生じる。When the inner pipe is expanded while suppressing the diameter expansion of the protruding portion, most of the portion except the vicinity of the protruding portion will be in a close contact state. When the extension inner pipe is joined to the tip of the inner pipe, the projecting portion of the inner pipe is not expanded, so that a working space is secured when joining the extension outer pipe to the outer pipe. By extending the inner pipe, expanding the pipe, and extending the outer pipe with the protruding amount of the extended outer pipe reduced, the extension dimension of the double metal pipe becomes free.

【０００８】[0008]

【実施例】以下、本発明に係る防食方法及び耐食性容器
の一実施例について、図１ないし図５に基づいて説明す
る。各図において、符号１は外管、２は内管、３は拘束
治具、４は内圧負荷治具、１１は延長外管、１２は延長
内管、Ｗはシール溶接部である。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the anticorrosion method and the corrosion resistant container according to the present invention will be described below with reference to FIGS. In each drawing, reference numeral 1 is an outer pipe, 2 is an inner pipe, 3 is a restraining jig, 4 is an internal pressure load jig, 11 is an extended outer pipe, 12 is an extended inner pipe, and W is a seal weld.

【０００９】前記拘束治具３にあっては、図１及び図２
に示すように、内管２に外嵌めされる二つ割状のクラン
プブラケット３１と、該クランプブラケット３１を締結
して内管２の外周に固定するための締結ボルト３２及び
ナット３３とを有するものとされる。In the restraint jig 3, as shown in FIGS.
As shown in FIG. 2, it has a halved clamp bracket 31 that is externally fitted to the inner pipe 2, and a fastening bolt 32 and a nut 33 for fastening the clamp bracket 31 and fixing it to the outer periphery of the inner pipe 2. To be taken.

【００１０】前記内圧負荷治具４にあっては、内管２の
先端開口（延長される端部の開口）を閉塞するキャップ
状のものであり、内管２の先端外周にシール溶接部Ｗに
よって一体に取り付けられる。The inner pressure load jig 4 is a cap-like member that closes the tip opening (the opening of the extended end) of the inner tube 2, and the seal welding portion W is formed on the outer circumference of the tip of the inner tube 2. Are attached together by.

【００１１】以下、二重金属管の製造工程に沿って説明
する。The process for manufacturing the double metal tube will be described below.

【００１２】〔外管及び内管の組み合わせ〕図１に示す
ように、外管１の中に若干長い内管２を挿入して、内管
２の先端を外管１の先端よりも突出させた状態に組み合
わせる。なお、図１において記載が省略されている外管
１及び内管２の基部にあっては、一体化が図られている
ものとする。[Combination of Outer Tube and Inner Tube] As shown in FIG. 1, a slightly longer inner tube 2 is inserted into the outer tube 1 so that the tip of the inner tube 2 is projected more than the tip of the outer tube 1. Combine to the state. The bases of the outer pipe 1 and the inner pipe 2, which are not shown in FIG. 1, are assumed to be integrated.

【００１３】〔拘束治具及び内圧負荷治具の取り付け〕
拘束治具３にあっては、図２に示すように、内管２の突
出部分２ａの外周をクランプブラケット３１で囲むよう
に取り付けられ、締結ボルト３２及びナット３３によっ
て内管２の外周面とクランプブラケット３１の内面とを
密着させた状態で、かつ外管１の先端開口部にほぼ密接
した状態とする。内圧負荷治具４にあっては、図１に示
すように、拘束治具３よりも先端方向の位置において、
内管２の外周面にシール溶接部Ｗにより取り付けられ
る。[Installation of restraint jig and internal pressure load jig]
As shown in FIG. 2, the restraint jig 3 is attached so that the outer periphery of the protruding portion 2a of the inner pipe 2 is surrounded by the clamp bracket 31, and is fastened to the outer peripheral surface of the inner pipe 2 by the fastening bolts 32 and the nuts 33. The clamp bracket 31 is in close contact with the inner surface thereof and is also in close contact with the tip opening of the outer tube 1. In the internal pressure load jig 4, as shown in FIG.
It is attached to the outer peripheral surface of the inner pipe 2 by a seal welding portion W.

【００１４】〔内管の拡管〕内管２の突出部分２ａの寸
法変化、つまり、膨張を拘束治具３によって抑制した状
態で、図３の各矢印で示すように、内管２の中に加圧流
体を注入して内管２を拡管する。内管２の突出部分２ａ
の拡径を抑制しながら内管２を拡径すると、内管２の大
部分が外管１に密着した状態となる。この際に拘束治具
３の近傍や外管１の先端開口部近傍にあっては、内管２
の突出部分２ａが拡管されないまま残される。[Expansion of Inner Tube] In a state where the dimensional change of the protruding portion 2a of the inner tube 2, that is, the expansion is suppressed by the restraint jig 3, the inner tube 2 is inserted into the inner tube 2 as shown by the arrows in FIG. A pressurized fluid is injected to expand the inner tube 2. Protruding portion 2a of inner tube 2
When the inner tube 2 is expanded while suppressing the expansion of the inner tube 2, most of the inner tube 2 is in close contact with the outer tube 1. At this time, in the vicinity of the restraint jig 3 or the tip opening portion of the outer tube 1, the inner tube 2
The projecting portion 2a of is left unexpanded.

【００１５】〔内管の延長〕締結ボルト３２及びナット
３３を緩めて拘束治具３を外すとともに、例えばシール
溶接部Ｗよりも若干内側の位置で内管２の突出部分２ａ
を切断し、そして、切断した先に、図４に示すように、
延長内管１２を接合する。この場合の接合は、例えば拡
散接合等が変形を極力抑制する意味で好適である。ま
た、接合部分Ｊにあっては、非破壊検査、漏洩試験等を
適宜実施して、健全性の確認が行なわれる。さらに、接
合部分Ｊの表面には、必要に応じてセラミックスコート
等の表面処理が実施される。[Extension of Inner Pipe] The fastening bolt 32 and the nut 33 are loosened to remove the restraint jig 3, and the protruding portion 2a of the inner pipe 2 is located at a position slightly inside the seal weld W, for example.
And then at the end of the cut, as shown in FIG.
The extension inner pipe 12 is joined. In this case, for example, diffusion bonding is suitable for suppressing deformation as much as possible. Further, at the joint portion J, nondestructive inspection, leakage test, etc. are appropriately performed to confirm the soundness. Further, the surface of the joint portion J is subjected to surface treatment such as ceramics coating, if necessary.

【００１６】〔外管の延長〕外管１の先端に延長外管１
１を接合する。この延長外管１１にあっては、図５に示
すように、延長内管１２よりも突出量が少なくなるよう
に図１に準じて設定される。内管２に延長内管１２を接
合した状態にあっても、突出部分２ａの拡径がなされて
いないため、外管１の先端部と突出部分２ａとの間に間
隙が生じた状態とされており、外管１に延長外管１１を
接合する際の作業スペースが確保され、かつ、この作業
スペースにより、外管１及び延長外管１１の接合に際し
て、延長内管１２と融着する等の事故の発生が防止され
る。なお、外管１と延長外管１１との接合部分Ｋにあっ
ても、非破壊検査、漏洩試験等を適宜実施して、健全性
の確認が行なわれる。これらの検査や作業時にあって
も、前述の作業スペースを利用して好適に実施される。[Extension of Outer Tube] The outer tube 1 is extended to the tip of the outer tube 1.
Join 1 As shown in FIG. 5, the extension outer tube 11 is set according to FIG. 1 so that the extension amount is smaller than that of the extension inner tube 12. Even when the extended inner tube 12 is joined to the inner tube 2, since the diameter of the protruding portion 2a is not expanded, it is considered that there is a gap between the tip portion of the outer tube 1 and the protruding portion 2a. Therefore, a working space for joining the extended outer pipe 11 to the outer pipe 1 is secured, and by this working space, when the outer pipe 1 and the extended outer pipe 11 are joined, the working space is fused with the extended inner pipe 12. The occurrence of accidents is prevented. Even at the joint portion K between the outer tube 1 and the extended outer tube 11, nondestructive inspection, leak test, etc. are appropriately performed to confirm the soundness. Even during these inspections and work, the work space described above is used to carry out the work suitably.

【００１７】〔延長工程の繰り返し〕以下、図１ないし
図５例で示したように、延長外管１１の突出量を少なく
しておいて、延長内管１２の接合、拡管、延長外管１１
の接合を繰り返すことにより、延長長さの制限を受ける
ことなく、長大な二重金属管を製造することが可能とな
る。[Repeat of Extension Step] Hereinafter, as shown in FIGS. 1 to 5, the extension outer tube 11 is made to have a small protruding amount, and the extension inner tube 12 is joined, expanded, and extended outer tube 11
By repeating the above-mentioned joining, it becomes possible to manufacture a long double metal pipe without being restricted by the extension length.

【００１８】[0018]

【発明の効果】本発明に係る二重金属管の製造方法にあ
っては、以下のような効果を奏する。 （１） 延長外管の突出量を少なくしておいて、延長内
管の接合、拡管、延長外管の接合を繰り返すことによ
り、実質的に制限を受けずに長大な二重金属管を製造す
ることができる。 （２） 内管及び延長内管の拡管時に、外管及び延長外
管との間に間隙を形成することにより、作業スペースを
確保して製造時の作業性を向上させることができる。 （３） 作業スペースの確保により、接合部分の検査等
を容易に実施することができる。 （４） 上記により、外管及び内管の融着等の相互の接
合を抑制することができる。The method of manufacturing a double metal tube according to the present invention has the following effects. (1) A long double metal pipe is manufactured without being substantially limited by repeating the joining of the extension inner pipe, the pipe expansion, and the joining of the extension outer pipe after reducing the protruding amount of the extension outer pipe. be able to. (2) By forming a gap between the outer pipe and the extended outer pipe when expanding the inner pipe and the extended inner pipe, it is possible to secure a working space and improve workability during manufacturing. (3) By securing a working space, it is possible to easily carry out an inspection or the like of the joint portion. (4) Due to the above, mutual joining such as fusion bonding of the outer pipe and the inner pipe can be suppressed.

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

【図１】本発明に係る二重金属管の製造方法の実施状況
を示す要部の正断面図である。FIG. 1 is a front cross-sectional view of an essential part showing a state of implementation of a method for manufacturing a double metal tube according to the present invention.

【図２】図１の拘束治具の平面図である。FIG. 2 is a plan view of the restraint jig of FIG.

【図３】図１から内管を拡管した状態の正断面図であ
る。FIG. 3 is a front cross-sectional view showing a state where the inner pipe is expanded from FIG.

【図４】図３から内管を延長した状態の正断面図であ
る。FIG. 4 is a front cross-sectional view of a state in which an inner tube is extended from FIG.

【図５】図４から外管を延長した状態の正断面図であ
る。FIG. 5 is a front cross-sectional view showing a state in which an outer tube is extended from FIG.

【図６】二重金属管の構造例を示す一部を破断した正面
図である。FIG. 6 is a partially cutaway front view showing a structural example of a double metal tube.

【符号の説明】[Explanation of symbols]

１ 外管 ２ 内管 ２ａ 突出部分 ３ 拘束治具 ４ 内圧負荷治具 １１ 延長外管 １２ 延長内管 ３１ クランプブラケット ３２ 締結ボルト ３３ ナット Ｗ シール溶接部 Ｊ 接合部分 Ｋ 接合部分 1 Outer pipe 2 Inner pipe 2a Projection part 3 Restraint jig 4 Internal pressure load jig 11 Extended outer pipe 12 Extended inner pipe 31 Clamp bracket 32 Fastening bolt 33 Nut W Seal weld J joint K joint

Claims (1)

【特許請求の範囲】[Claims] 【請求項１】 外管に先端を突出させた状態の内管を挿
入する工程と、内管の突出部分の寸法変化を抑制しなが
ら内管を拡管して外管に密着させる工程と、内管の突出
部分の先端に延長内管を接合する工程と、外管に延長内
管よりも突出量の少ない延長外管を接合する工程とが繰
り返されることを特徴とする二重金属管の製造方法。1. A step of inserting an inner tube with a tip protruding into the outer tube, a step of expanding the inner tube and closely contacting the outer tube while suppressing a dimensional change of a protruding portion of the inner tube, A method of manufacturing a double metal pipe, characterized in that a step of joining an extension inner pipe to a tip of a protruding portion of the pipe and a step of joining an extension outer pipe having a smaller amount of protrusion than the extension inner pipe to an outer pipe are repeated. .