JP2587256Y2 - Multi-tube heat exchanger - Google Patents
Multi-tube heat exchangerInfo
- Publication number
- JP2587256Y2 JP2587256Y2 JP1990021649U JP2164990U JP2587256Y2 JP 2587256 Y2 JP2587256 Y2 JP 2587256Y2 JP 1990021649 U JP1990021649 U JP 1990021649U JP 2164990 U JP2164990 U JP 2164990U JP 2587256 Y2 JP2587256 Y2 JP 2587256Y2
- Authority
- JP
- Japan
- Prior art keywords
- tube
- titanium
- plate
- auxiliary
- heat exchanger
- 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 - Fee Related
Links
Landscapes
- Details Of Heat-Exchange And Heat-Transfer (AREA)
- Heat-Exchange Devices With Radiators And Conduit Assemblies (AREA)
Description
【考案の詳細な説明】 （産業上の利用分野） この考案は、シェル内の管板間に多数本のチューブを
配設した多管式熱交換器に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multi-tube heat exchanger in which a number of tubes are arranged between tube sheets in a shell.
（従来の技術） 従来の多管式熱交換器は、その主要な構成部材たる管
板、熱交換器用チューブが炭素鋼製（SS製）で形成され
ているのが一般である。そして、上記チューブ内には反
応流体（プロセスガス）が、また、チューブの外部に
は、冷却媒体たる冷却水が通流使用されている。この従
来の多管式熱交換器では、チューブ表面の局部腐食、い
わゆる孔食の発生により、チューブ外部の冷却水が反応
流体に侵入するという不具合が生じる。(Prior Art) In a conventional multitubular heat exchanger, a tube plate and a heat exchanger tube, which are main components, are generally made of carbon steel (made of SS). A reaction fluid (process gas) flows through the tube, and cooling water as a cooling medium flows outside the tube. In this conventional multi-tubular heat exchanger, there occurs a problem that cooling water outside the tube enters the reaction fluid due to local corrosion of the tube surface, that is, pitting corrosion.
上記孔食の発生は、冷却水中に存在する不純物が水ア
カとなってチューブ表面に付着し、冷却水中の溶存酸素
に起因して、炭素鋼製チューブ表面と冷却水とが酸素濃
淡電池を形成し、電気化学的腐食を生ずることに依る。
そして、上記チューブの内外温度の差によって上述の電
気化学的腐食作用が促進されていた。The occurrence of the pitting corrosion is such that impurities present in the cooling water become water residue and adhere to the tube surface, and due to dissolved oxygen in the cooling water, the carbon steel tube surface and the cooling water form an oxygen concentration cell. And electrochemical corrosion.
And the above-mentioned electrochemical corrosion action was promoted by the difference between the inside and outside temperatures of the tube.
この点、耐食性、殊に耐孔食性に弱い炭素鋼に変え
て、オーステナイト・ステンレス鋼でチューブを形成す
ることも考えられるが、内外温度差の大きな環境下では
耐孔食性は期待できず、応力腐食割れの発生が懸念され
る。In this regard, it is conceivable to change the carbon steel, which has low corrosion resistance, especially pitting corrosion resistance, to a tube made of austenitic stainless steel. There is a concern that corrosion cracking may occur.
そこで、チューブ構成材料として、成形性、溶接性に
優れ、著しい耐食性のあるチタン材を採用することが考
えられる。Therefore, it is conceivable to use a titanium material which is excellent in formability and weldability and has remarkable corrosion resistance as a tube constituent material.
チタンは、活性な金属であるが良好な耐食性を示す。
これは、表面に不働態化被覆を形成することに起因して
いる。各種腐食環境下においてもステンレス鋼より良好
な耐食性を有し、孔食、隙間腐食に対し優れた性質を持
っている。Titanium is an active metal but exhibits good corrosion resistance.
This is due to the formation of a passivating coating on the surface. It has better corrosion resistance than stainless steel even in various corrosive environments, and has excellent properties against pitting and crevice corrosion.
さらに、チタンは、加工箇所や、溶接により熱影響を
受けた箇所も、母材と比較してその耐食性はほとんど低
下せず応力腐食割れを発生しないなどの特徴を持ってい
る。Further, titanium has features such that the corrosion resistance is hardly reduced and stress corrosion cracking does not occur even in a processed part or a part which is thermally affected by welding as compared with the base metal.
（考案が解決しようとする課題） しかし、熱交換器の構成材全てをチタン製とすると製
造コストが高くなる。そこで、熱交換器のチューブのみ
をチタン製とし、他の構成材を従来から使用されている
炭素鋼製とすることが考えられる。(Problems to be solved by the invention) However, if all the components of the heat exchanger are made of titanium, the production cost increases. Therefore, it is conceivable that only the tube of the heat exchanger is made of titanium and the other components are made of carbon steel which has been conventionally used.
ところが、この場合には、異種金属間の接合に問題を
生じる。すなわち、通常、異種金属を接合する場合、一
般にろう付けによりなされるところ、例えば、ろう付け
としてリチウム入銀ろうを使用し、アルゴン雰囲気にて
ろう付けを行なったとしても、せん断強度が充分でなく
シール強度に問題を生ずる。However, in this case, there is a problem in joining between dissimilar metals. That is, usually, when joining dissimilar metals, where generally performed by brazing, for example, using lithium-containing silver brazing as brazing, even if brazing is performed in an argon atmosphere, the shear strength is not sufficient. This causes a problem in seal strength.
本考案は、上記事情に鑑みてなされたもので、シール
製がよく、しかも、耐孔食性を有する多管式熱交換器を
できる限り安価に提供することを課題としてなされた。The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a multi-tubular heat exchanger that is made of a seal and has pitting resistance as low as possible.
（課題を解決するための手段） 本願第１請求項に記載した考案は、シェル内の管板間
に多数本のチューブを配設した多管式熱交換器におい
て、前記管板の一側面にチタン製の補助管板をチタン製
ビスにより取付け、前記管板及び補助管板を貫通するチ
ューブをチタンで形成し、前記ビスの頭と補助管板をシ
ール溶接するとともに、前記チューブと補助管板を溶着
した構成の多管式熱交換器である。(Means for Solving the Problems) The invention described in claim 1 of the present application is directed to a multi-tube heat exchanger in which a number of tubes are arranged between tube plates in a shell. A titanium auxiliary tube plate is attached with titanium screws, a tube passing through the tube plate and the auxiliary tube plate is formed of titanium, and the head of the screw and the auxiliary tube plate are seal-welded, and the tube and the auxiliary tube plate are welded. This is a multi-tube heat exchanger having a configuration in which is welded.
また、本願第２請求項に記載した考案は、シェル内の
管板間に多数本のチューブを配設した多管式熱交換器に
おいて、前記管板の一側面にチタン製の補助管板をチタ
ン製ビスにより取付け、前記管板及び補助管板を貫通す
るチューブをチタンで形成し、前記補助管板におけるチ
ューブ挿嵌孔の外周には溝を形成し、前記ビスの頭と補
助管板をシール溶接するとともに、前記チューブと補助
管板を溶着した構成の多管式熱交換器である。According to a second aspect of the present invention, in a multi-tube heat exchanger in which a number of tubes are arranged between tube sheets in a shell, an auxiliary tube sheet made of titanium is provided on one side surface of the tube sheet. A tube that is attached with a titanium screw and penetrates the tube plate and the auxiliary tube plate is formed of titanium, a groove is formed on the outer periphery of the tube insertion hole in the auxiliary tube plate, and the head of the screw and the auxiliary tube plate are connected. This is a multi-tube heat exchanger having a configuration in which the tube and the auxiliary tube plate are welded together with seal welding.
（作用） 上記のように構成した場合は、チューブがチタン製で
あるため、成形性、溶接性に優れ、著しく耐孔食性が向
上する。他方、チューブは補助管板に溶接されるので、
同種金属間の接合による密着性、シール性の向上が確保
される。また、チタン製のビス及び補助管板の溶着によ
って密着性、シール性の向上がなされるので、補助管板
と管板との間における液漏れ（熱交換器の内圧により生
ずる液漏れ）が回避される。さらに、第２の考案のよう
に補助管板のチューブ挿嵌孔外周に溝を形成した場合
は、薄肉のチューブに対し厚肉である補助管板の当該溶
着部位を、可及的に薄肉とすることができ、これにより
両者の溶接部を均一に加熱することが可能となる。(Operation) In the case of the above configuration, since the tube is made of titanium, the tube is excellent in moldability and weldability, and pitting corrosion resistance is remarkably improved. On the other hand, the tube is welded to the auxiliary tubesheet,
Improvements in adhesion and sealing due to bonding between similar metals are ensured. In addition, since the adhesion and sealing properties are improved by welding the titanium screw and the auxiliary tube plate, liquid leakage between the auxiliary tube plate and the tube plate (liquid leakage caused by the internal pressure of the heat exchanger) is avoided. Is done. Furthermore, when a groove is formed on the outer periphery of the tube insertion hole of the auxiliary tube plate as in the second invention, the welding portion of the auxiliary tube plate that is thicker than the thin tube is made as thin as possible. This makes it possible to heat both welds uniformly.
（実施例） 第１図は、本考案の一実施例を示す図で、管板とチュ
ーブの挿嵌部位の断面図、第２図は第１図におけるＡ部
拡大図、第３図は同Ｂ部拡大図、第４図は同Ｂ部の他の
溶接法外略図、第５図は同Ｃ部拡大図である。(Embodiment) FIG. 1 is a view showing an embodiment of the present invention, and is a cross-sectional view of an insertion portion of a tube sheet and a tube, FIG. 2 is an enlarged view of a portion A in FIG. 1, and FIG. FIG. 4 is an enlarged schematic view of another welding method of the B portion, and FIG. 5 is an enlarged view of the C portion.
図において、１は、図示を省略したシェル内に配設さ
れた炭素鋼製管板、２はチタン製補助管板であり、該チ
タン製補助管板２はチタン製ビス３によって炭素鋼製管
板１に取付けられている。In the drawing, reference numeral 1 denotes a carbon steel tube plate disposed in a shell (not shown), reference numeral 2 denotes a titanium auxiliary tube plate, and the titanium auxiliary tube plate 2 is formed of a carbon steel tube by a titanium screw 3. It is attached to the plate 1.
上記チタン製補助管板２と炭素鋼製管板１との取付け
は、具体的には炭素鋼製管板１に螺子穴４を、そしてチ
タン製補助管板２にビス挿嵌孔５を形成しておき、上記
螺子穴４にビス挿嵌孔５を照合させ、チタン製ビス３
（皿ビス）をチタン製補助管板２側から螺入して締め付
ける。その後、チタン製ビス３の頭3aをチタン製補助管
板２にシール溶接し、溶接後に機械加工を施す。つま
り、チタン製補助管板２の表面側は、後に鏡板（図示を
省略）がガスケット（図示を省略）を介して取付けられ
る部位であって、凹凸の存する表面性状は好ましくない
からである。なお、チタン製補助管板２の外周縁部に
は、上記ガスケット取付け用の凹陥部2aが形成されてい
る。Specifically, the titanium auxiliary tube sheet 2 and the carbon steel tube sheet 1 are attached by forming a screw hole 4 in the carbon steel tube sheet 1 and a screw insertion hole 5 in the titanium auxiliary tube sheet 2. The screw insertion hole 5 is matched with the screw hole 4 and the titanium screw 3
(Tray screw) is screwed in from the titanium auxiliary tube plate 2 side and tightened. Thereafter, the head 3a of the titanium screw 3 is seal-welded to the titanium auxiliary tube sheet 2 and machined after welding. In other words, the surface side of the titanium auxiliary tube plate 2 is a portion to which a head plate (not shown) is later attached via a gasket (not shown), and the surface property having unevenness is not preferable. Note that a recess 2a for attaching the gasket is formed on the outer peripheral edge of the titanium auxiliary tube plate 2.
６は、炭素鋼製管板１とチタン製補助管板２とのシー
ル性を考慮し両管板1,2の外周端縁間に配設されたガス
ケットであり、上記ガスケット６を介設しやすいように
上記炭素鋼製管板１の外周端縁には凹陥部1aをリング状
に形成している。Reference numeral 6 denotes a gasket disposed between the outer peripheral edges of the tube sheets 1 and 2 in consideration of the sealing property between the carbon steel tube sheet 1 and the titanium auxiliary tube sheet 2. A concave portion 1a is formed in a ring shape on the outer peripheral edge of the carbon steel tube sheet 1 so as to be easy.
また、他の炭素鋼製管板１とチタン製補助管板２間の
シール性を考慮する方法としては、上述した炭素鋼製管
板の外周端縁に凹陥部1aを形成しないで、したがってガ
スケットを介設しないで、チタン製皿ビス３にて取付け
た後、チタン製補助管板２の外周と炭素鋼製管板１とを
リチウム入銀ろうでTIG溶接により溶接させることもで
きる。As another method for considering the sealing performance between the carbon steel tube sheet 1 and the titanium auxiliary tube sheet 2, there is no need to form the recessed portion 1 a at the outer peripheral edge of the carbon steel tube sheet, and therefore, the gasket is not used. Instead, the outer periphery of the titanium auxiliary tube sheet 2 and the carbon steel tube sheet 1 can be welded to the carbon steel tube sheet 1 by TIG welding using a lithium-implanted silver solder.
そして、上記炭素鋼製管板１とチタン製補助管板２と
には、相照合するチューブ挿嵌孔1b,2bが形成されてお
り、該チューブ挿嵌孔1b,2bにチタン製チューブ７を挿
嵌し、TIG溶接にて固着している。The carbon steel tube sheet 1 and the titanium auxiliary tube sheet 2 are provided with tube insertion holes 1b and 2b for phase matching, and a titanium tube 7 is inserted into the tube insertion holes 1b and 2b. Inserted and fixed by TIG welding.
上記チタン製補助管板２とチタン製チューブ７との固
着につき詳述すると、チタン製チューブ７の先端をチュ
ーブ挿嵌孔2bから約0.5mm突出させ、炭素鋼製管板１と
嵌合する部位におけるチタン製チューブ７を拡管（該拡
管部を符号８で示す）して固定し、上記約0.5mmほど突
出せしめられたチタン製チューブ７の先端部及びチュー
ブ挿嵌孔2b周縁を充分にクリーニングし、Arシール下に
TIG溶接を行なう。この溶接は、チタン同士（同種金
属）間の溶接であるため、円滑且つ確実になし得るとと
もに、両者間の密着性、シール性の向上が確保され得
る。The fixing of the titanium auxiliary tube plate 2 and the titanium tube 7 will be described in detail. The tip of the titanium tube 7 projects about 0.5 mm from the tube insertion hole 2b, and is fitted to the carbon steel tube plate 1. The titanium tube 7 is expanded and fixed (the expanded portion is indicated by reference numeral 8), and the tip of the titanium tube 7 protruding about 0.5 mm and the periphery of the tube insertion hole 2b are sufficiently cleaned. , Under the Ar seal
Perform TIG welding. Since this welding is welding between titanium (same metals), it can be performed smoothly and reliably, and the adhesion and sealing between them can be improved.
ところで、TIG溶接ではアークが安定し低入熱溶接が
可能であるが、チタン製補助管板肉厚と熱交換器チュー
ブ肉厚とは著しい寸法の相違があるため、熱交換器チュ
ーブ側に過度の加熱が施されるおそれがある。そこで、
厚肉のチタン製補助管板の溶接部外周に溝９を形成する
加工を加え、チタン製補助管板溶接部、熱交換器チュー
ブ溶接部がともに均一に加熱できるようになすのが好ま
しい。かくして、チタン製チューブ７を固定した後、ガ
スケット及び鏡板を取付けて、熱交換器が構成される。By the way, in TIG welding, the arc is stable and low heat input welding is possible.However, there is a remarkable dimensional difference between the thickness of the titanium auxiliary tube plate and the thickness of the heat exchanger tube. May be heated. Therefore,
It is preferable to add a process for forming a groove 9 around the welded portion of the thick titanium auxiliary tube sheet so that both the titanium auxiliary tube sheet weld and the heat exchanger tube weld can be uniformly heated. Thus, after fixing the titanium tube 7, the gasket and the end plate are attached to form a heat exchanger.
（考案の効果） 本考案は、以上説明したように構成され、チタン製で
あるため、成形性、溶接性に優れ、著しく耐孔食性が向
上する。そして、チューブは補助管板に溶接されるの
で、同種金属間に接合による密着性、シール性の向上が
確保される。また、チタン製のビス及び補助管板の溶着
によっても密着性、シール性の向上がなされるので、補
助管板と管板との間における液漏れが回避される。さら
に、第２の考案のように補助管板のチューブ挿嵌孔外周
に溝を形成した場合は、薄肉のチューブに対し厚肉であ
る補助管板の当該溶着部位を、可及的に薄肉とすること
ができ、これにより両者の溶接部を均一に加熱すること
が可能となる。しかも、チタン製部位がチューブと補助
管板のみに用いられて構造上必要かつ十分であり、これ
により熱交換器を安価に製作提供できるという効果があ
る。(Effects of the Invention) Since the present invention is configured as described above and is made of titanium, it is excellent in formability and weldability, and significantly improves pitting corrosion resistance. Then, since the tube is welded to the auxiliary tube sheet, the adhesion between the same kind of metal and the improvement of the sealing property by joining are ensured. Also, the adhesion and sealing properties are improved by welding the titanium screw and the auxiliary tube sheet, so that liquid leakage between the auxiliary tube sheet and the tube sheet is avoided. Further, when a groove is formed on the outer periphery of the tube insertion hole of the auxiliary tube plate as in the second invention, the welding portion of the auxiliary tube plate which is thicker than the thin tube is made as thin as possible. This makes it possible to heat both welds uniformly. In addition, since the titanium portion is used only for the tube and the auxiliary tube plate, it is necessary and sufficient in structure, so that there is an effect that the heat exchanger can be manufactured and provided at low cost.
第１図は本考案の一実施例を示す図で、管板とチューブ
の挿嵌部位の断面図、第２図は第１図におけるＡ部拡大
図、第３図は同Ｂ部拡大図、第４図は同Ｂ部の他の溶接
法概略図、第５図は同Ｃ部拡大図である。 １…炭素鋼製管板、２…チタン製補助管板 ３…チタン製ビスFIG. 1 is a view showing an embodiment of the present invention, and is a cross-sectional view of an insertion portion of a tube sheet and a tube, FIG. 2 is an enlarged view of a portion A in FIG. 1, FIG. FIG. 4 is a schematic view of another welding method of the part B, and FIG. 5 is an enlarged view of the part C. 1. Carbon steel tube sheet 2. Titanium auxiliary tube sheet 3. Titanium screw
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭61−134596（ＪＰ，Ａ) 実開 昭63−17983（ＪＰ，Ｕ) 実開 平１−129591（ＪＰ，Ｕ) (58)調査した分野(Int.Cl.6，ＤＢ名) F28F 9/02──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-61-134596 (JP, A) JP-A-63-17983 (JP, U) JP-A-1-125991 (JP, U) (58) Investigation Field (Int.Cl. 6 , DB name) F28F 9/02
Claims (2)
設した多管式熱交換器において、前記管板の一側面にチ
タン製の補助管板をチタン製ビスにより取付け、 前記管板及び補助管板を貫通するチューブをチタンで形
成し、 前記ビスの頭と補助管板をシール溶接するとともに、前
記チューブと補助管板を溶着したことを特徴とする多管
式熱交換器。1. A multi-tube heat exchanger in which a number of tubes are arranged between tube plates in a shell, a titanium auxiliary tube plate is attached to one side surface of the tube plate with titanium screws. A multi-tube heat exchanger, wherein a tube passing through the plate and the auxiliary tube plate is formed of titanium, the head of the screw and the auxiliary tube plate are seal-welded, and the tube and the auxiliary tube plate are welded.
設した多管式熱交換器において、 前記管板の一側面にチタン製の補助管板をチタン製ビス
により取付け、 前記管板及び補助管板を貫通するチューブをチタンで形
成し、 前記補助管板におけるチューブ挿嵌孔の外周には溝を形
成し、 前記ビスの頭と補助管板をシール溶接するとともに、前
記チューブと補助管板を溶着したことを特徴とする多管
式熱交換器。2. A multi-tube heat exchanger in which a number of tubes are arranged between tube plates in a shell, wherein an auxiliary tube plate made of titanium is attached to one side surface of the tube plate with a screw made of titanium. A tube penetrating the plate and the auxiliary tube plate is formed of titanium, a groove is formed on the outer periphery of the tube insertion hole in the auxiliary tube plate, and the head of the screw and the auxiliary tube plate are seal-welded, and the tube is connected to the tube. A multi-tubular heat exchanger characterized by welding an auxiliary tube sheet.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1990021649U JP2587256Y2 (en) | 1990-03-03 | 1990-03-03 | Multi-tube heat exchanger |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1990021649U JP2587256Y2 (en) | 1990-03-03 | 1990-03-03 | Multi-tube heat exchanger |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03112668U JPH03112668U (en) | 1991-11-18 |
| JP2587256Y2 true JP2587256Y2 (en) | 1998-12-16 |
Family
ID=31524686
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1990021649U Expired - Fee Related JP2587256Y2 (en) | 1990-03-03 | 1990-03-03 | Multi-tube heat exchanger |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2587256Y2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012072923A (en) * | 2010-09-27 | 2012-04-12 | Mdi Corp | Shell and tube type heat exchanger |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0610596B2 (en) * | 1984-12-06 | 1994-02-09 | 株式会社東芝 | Heat exchanger for heat pump device |
| JPS6317983U (en) * | 1986-07-22 | 1988-02-05 | ||
| JPH01129591U (en) * | 1988-02-19 | 1989-09-04 |
-
1990
- 1990-03-03 JP JP1990021649U patent/JP2587256Y2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03112668U (en) | 1991-11-18 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |