JPS5886394A - Heat exchanger - Google Patents

Abstract

PURPOSE:To prevent the stress corrosion cracking of the titled heat exchanger by a method wherein the height of the outer side wall of a groove of a core plate and the height of calking of the core plate are held in a predetermined relationship so that the stress generating on the surface of the bottom wall of the groove is converted into a stabilized compression stress. CONSTITUTION:A tongue-like guide 26 projecting toward the groove 20 of the core plate is provided on an internal operation surface 11 of a fixing section 10 of the edge of a tank 2. The tongue-like guide 26 projects downwardly from the inner side edge of the inner operation surface 11, that is, the part of the surface 11 adjacent the inner side wall 17 of the groove 20 so as to engage the inner side surface of a sealing member 21 to thereby prevent the displacement of the sealing member. Further, the height (h) of the outer side wall 18 of the groove 20 of the core plate and the height (H) of the calking of the core plate are so determined as to satisfy the relationship of (H-h)>=0.5mm. so that the load applied on the core plate at the time of calking is not transmitted to the bottom wall 19 of the groove 20 and the distortion of the surface of the bottom wall 19 takes place only in the direction of compression of the core plate.

Description

【発明の詳細な説明】 本発明は、金属製本体に合成樹脂製のタンクをかしめ作
業によって取付けた熱交換器の改良に関し、例えば自動
車用ラジェータに用いて好適なものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a heat exchanger in which a synthetic resin tank is attached to a metal body by caulking, and is suitable for use in, for example, an automobile radiator.

金属製本体にコアプレートを設け、このコアプレートの
外周縁を溝形に成形し、この溝内に、合成樹脂製タンク
の端縁に設けた、はぼ四角形断面の取付部を嵌合させ、
コアプレートの溝形部の外面に係合したかしめプレート
をこの取付部にかしめることによってタンクを本体に密
封装着する形式の熱交換器は公知である。溝に嵌合した
タンク端縁取付部の底面と溝底面との間には弾性シール
材が設置しであるが、この弾性シール材の直下の溝底壁
を構成しているコアプレート部分に、水質の悪い冷却水
を用いたときなどに、割れが生じ、熱交換器の寿命が短
かくなることがあった。これが応力腐食割れであること
を本発明者らはつきとめた。応力腐食割れというのは、
腐食という化学的な働きと応力という物理的な働きの相
乗作用によって生じる割れのことである。A core plate is provided on the metal body, the outer peripheral edge of this core plate is formed into a groove shape, and a mounting portion with a rectangular cross section provided on the edge of a synthetic resin tank is fitted into this groove,
Heat exchangers are known in which a tank is hermetically mounted to a main body by caulking a caulking plate that engages with the outer surface of a grooved portion of a core plate to this attachment portion. An elastic sealing material is installed between the bottom surface of the tank edge attachment part that fits into the groove and the groove bottom surface, but the core plate part that makes up the groove bottom wall directly under this elastic sealing material, When using poor quality cooling water, cracks could occur and the life of the heat exchanger could be shortened. The inventors found that this was stress corrosion cracking. Stress corrosion cracking is
Cracking is caused by the synergistic effect of the chemical action of corrosion and the physical action of stress.

本発明の目的はこのような応力腐食割れを防いで前記形
式の熱交換器の寿命を延ばすことにある。It is an object of the present invention to prevent such stress corrosion cracking and to extend the life of heat exchangers of the type described above.

以下、添付図面を参照しながらより詳しく説明する。A more detailed explanation will be given below with reference to the accompanying drawings.

第１図は本発明に係る熱交換器、たとえば自動車用ラジ
ェータを示しており、ラジェータは銅製のコルゲートフ
ィン７と黄銅製のチューブ８を含む金属製の本体１とそ
の上、下端に密封装着した合成樹脂製のタンク２，３と
を包含する。上方のタンク２には冷却水補給口４と冷却
水流入パイプ５とが設けてあり、下方タンク３には冷却
水流出バイブロが設けであるが、基本的に上、下のタン
クは同じ構造であるから、以下、上方のタンク２につい
てのみ説明する。上下を逆にして考えれば、以下の説明
は下方タンク３にも適用できることは了解されたい。FIG. 1 shows a heat exchanger according to the present invention, for example, a radiator for an automobile. It includes tanks 2 and 3 made of synthetic resin. The upper tank 2 is provided with a cooling water supply port 4 and a cooling water inflow pipe 5, and the lower tank 3 is provided with a cooling water outflow vibro, but basically the upper and lower tanks have the same structure. Therefore, only the upper tank 2 will be described below. It should be understood that the following explanation can also be applied to the lower tank 3 if considered upside down.

第２図はタンク２を本体１に密封装着する従来方法を示
しており、タンク２は一端開放となっており、これをコ
ルゲートフィン７の付いたチューブ８から成る本体１の
端部にかぶせることによってタンク２が完全となる。タ
ンクの開放端縁の全周に沿ってほぼ四角形断面の取付部
１０が設けである。この取付部１０は互に平行で平らな
表面を持つ内、外の作用面１１．１２とこれら内外作用
面に対して直角の内、外の側壁面１３．１４とを有する
。FIG. 2 shows a conventional method of sealingly attaching the tank 2 to the main body 1. The tank 2 is open at one end, and is placed over the end of the main body 1 consisting of a tube 8 with corrugated fins 7. Tank 2 is now complete. A mounting portion 10 of approximately square cross section is provided along the entire circumference of the open edge of the tank. The mounting part 10 has inner and outer working surfaces 11.12 with plane surfaces parallel to each other and inner and outer side wall surfaces 13.14 at right angles to these working surfaces.

本体１、すなわちチューブ７の側面にはその上端付近で
周方向に黄銅製のコアプレート１６が適当な手段、たと
えば半田付、ろう付は等で固着しである。コアプレート
１６の外周縁は内、外の側壁１７．１８および底壁１９
を有する溝部２０となるように成形しである。A brass core plate 16 is fixed to the side surface of the main body 1, that is, the tube 7, in the circumferential direction near its upper end by suitable means, such as soldering, brazing, etc. The outer periphery of the core plate 16 includes inner and outer side walls 17, 18 and a bottom wall 19.
The groove portion 20 is formed so as to have a groove portion 20 having a shape.

組立時、溝部２０にタンク２の端縁取付部１０が嵌め込
まれ、このとき、取付部１０の内、外の側壁面１３．１
４はそれぞれ溝部２０の内、外の側壁１７．１８と係合
し、取付部１０の内方作用面１１と溝部底壁１９の内面
との間にはゴム製０リングからなる弾性シール材２１が
設置される。During assembly, the edge attachment portion 10 of the tank 2 is fitted into the groove portion 20, and at this time, the inner and outer side wall surfaces 13.1 of the attachment portion 10 are fitted into the groove portion 20.
4 engage with the inner and outer side walls 17 and 18 of the groove 20, respectively, and between the inner working surface 11 of the mounting portion 10 and the inner surface of the groove bottom wall 19 is an elastic sealing material 21 made of a rubber O-ring. will be installed.

次に、頂縁につめ部２２を有するほぼＬ字形（図では逆
り字形になっているが、反対側ではＬ字形である）の断
面を持つ鉄板製のかしめプレート２３をコアプレート１
６の溝部２０に係合させ、つめ部２２をタンク２の端縁
取付部１０の外方作用面１２に向ってかしめる。その結
果、タンク端縁取付部１０はその内方作用面１１で弾性
シール材２１を変形すると共にコアプレート１６の溝部
２０に堅固に密封装着されることになる。なお、第２図
で、コアプレート溝部２０の外方側壁１８の、溝底壁１
９の内面からの高さｈが同じ内面からかしめ面、すなわ
ち取付部１０の゛外方作用面１２までの距離、すなわち
、かしめ高さＨとほぼ同じとなっていることをご記憶願
いたい。Next, a caulking plate 23 made of an iron plate having an approximately L-shaped cross section (inverted in the figure, but L-shaped on the opposite side) with a claw portion 22 at the top edge is attached to the core plate 1.
6 and swage the pawl portion 22 toward the outward working surface 12 of the edge attachment portion 10 of the tank 2. As a result, the tank edge attachment portion 10 deforms the elastic sealing material 21 on its inner working surface 11 and is securely and sealingly attached to the groove portion 20 of the core plate 16. In addition, in FIG. 2, the groove bottom wall 1 of the outer side wall 18 of the core plate groove portion 20
Please remember that the height h from the inner surface of 9 is approximately the same as the distance from the same inner surface to the caulking surface, that is, the outward acting surface 12 of the mounting portion 10, that is, the caulking height H.

以上の構成において、タンク２の内部Ａに存在する冷却
水が、コアプレート溝部２０の内面、タンク取付部１０
の内面および弾性シール材２１の表面で形成された空間
２４を経て、コアプレート溝底壁１９と弾性シール材２
１との間に形成されるすきま部に浸透し、すきま腐食環
境が生じる。In the above configuration, the cooling water present in the interior A of the tank 2 is distributed between the inner surface of the core plate groove 20 and the tank mounting portion 10.
The core plate groove bottom wall 19 and the elastic sealing material 2 pass through the space 24 formed by the inner surface of the
It penetrates into the gap formed between 1 and 1, creating a crevice corrosion environment.

すなわち、すきま部に溜った液体中の腐食性成分が拡散
しにくい上に、黄銅製のコアプレート表面の不動態皮膜
（酸化皮膜）はその不動態を保持しようとして、このす
きま部内の液体中の酸素を消費し、そのため、このすき
ま部内の液体とタンク内の液体との間に酸素の濃度差が
生じ、酸素濃淡電池が形成される。その電池の作用によ
り、このすきま部内の液体の−が低下し、この結果生じ
る腐食環境は非常にきびしいものとなる。In other words, corrosive components in the liquid that accumulates in the gap are difficult to diffuse, and the passive film (oxide film) on the surface of the brass core plate tries to maintain its passivity, causing the liquid in the gap to spread. Oxygen is consumed, so that a difference in oxygen concentration occurs between the liquid in this gap and the liquid in the tank, forming an oxygen concentration cell. Due to the action of the battery, the liquid content in this gap decreases, and the resulting corrosive environment becomes very severe.

それに加えて、第２図に関連して先に指摘したように、
コアプレート溝部２０の外方側壁１８の高さｈとかしめ
高さＨとが等しいため、かしめプレート２３のつめ部２
２の曲げ加工時に加わる曲げ荷重が溝部の外方側壁１８
を経て底壁１９に伝えられ、そこに引張応力を生じさせ
、かしめ作業終了後もこの応力が残留する。In addition, as pointed out earlier in connection with Figure 2,
Since the height h of the outer side wall 18 of the core plate groove 20 and the caulking height H are equal, the claw portion 2 of the caulking plate 23
The bending load applied during the bending process in step 2 is applied to the outer side wall 18 of the groove.
The tension is transmitted to the bottom wall 19 through the swage, generating tensile stress there, and this stress remains even after the caulking operation is completed.

以上の条件の下で、コアプレート溝部２０の底壁１９に
応力腐食割れが容易に生じることは明らかである。この
事実に本発明者らが始めて気付き、種々の実験の結果、
本発明に到達したのである。It is clear that stress corrosion cracking easily occurs in the bottom wall 19 of the core plate groove 20 under the above conditions. The inventors were the first to notice this fact, and as a result of various experiments,
The present invention has been achieved.

その際、アンモニア等の成分を多く含む通常の水を冷却
水として用いた場合、割れ寿命の悪化が著しいことも合
わせて確認した。At that time, it was also confirmed that when ordinary water containing a large amount of components such as ammonia was used as cooling water, the cracking life deteriorated significantly.

以下、第５図を参照しながら応力発生のメカニズムをよ
り詳しく説明する。第５図の（イ）は、コアプレート溝
部２０の底に弾性シール材２１を置き、この溝部２０に
タンク端縁取付部１０を嵌め込み、溝部２０の外面にか
しめプレート２３を係合させた段階を示す。このとき、
かしめ作業前なので、当然、溝部２０の底壁１９にはひ
ずみが生じていない。第５図の（ロ）の段階で、かしめ
作業を開始すると、かしめプレート２３のつめ部２２に
は斜め荷重Ｆｌがかかり、溝部２０の外方側壁１８がタ
ンク端縁取付部１０に押し付けられながら下向きの力を
受けて変形し、溝部２０の底壁１９に圧縮方向のひずみ
ε。が発生する。さらにかしめ作業が進行すると、第５
図の（／今に示すように、荷重が完全に垂直方向の荷重
に変わり、それが外方側壁１８を経て溝部底壁１９に伝
わる。このとき、溝部２０の外面はかしめプレート２３
で拘束されているため、溝部底壁１９は弾性シール材２
１に向って凸状の変形を行ない、その表面に引張り方向
のひずみε１が生じる。第５図に）かしめ作業終了段階
で、荷重Ｆ２が除かれ、かしめプレート２３のつめ部２
２がスプリングバック作用の下に上方に少しもどる。し
たがって、溝部底壁１９の表面のひずみはε２まで低下
する。このとき、底壁１９は塑性変形ひずみε３も含ん
であり、もしこの状態でかしめプレート２３を除去して
拘束を解いたならば、底壁１９は弾性ひずみ量ε２−６
３の分だけ初期状態にもどることになる。この弾性ひず
み量ε、−６３が応力腐食割れに参加するひずみ量であ
る。そこで、第２図に示す従来構造（すなわちＨ−ｈ＝
Ｑ）のひずみ発生パターンを実線で表わすと、溝部底壁
１９の表面に引張方向の弾性ひずみが生じていることが
わかる。Hereinafter, the mechanism of stress generation will be explained in more detail with reference to FIG. FIG. 5A shows a stage in which the elastic sealing material 21 is placed at the bottom of the core plate groove 20, the tank edge attachment part 10 is fitted into this groove 20, and the caulking plate 23 is engaged with the outer surface of the groove 20. shows. At this time,
Since the caulking work has not yet been performed, there is naturally no distortion in the bottom wall 19 of the groove portion 20. When the caulking work is started at the stage (b) in FIG. The bottom wall 19 of the groove 20 is deformed by receiving a downward force, and the bottom wall 19 of the groove 20 is subjected to strain ε in the compressive direction. occurs. As the caulking work progresses further, the fifth
As shown in FIG.
Since the groove bottom wall 19 is restrained by the elastic sealing material 2
1, and a strain ε1 in the tensile direction is generated on the surface. (See Fig. 5) At the end of the caulking work, the load F2 is removed and the pawl portion 2 of the caulking plate 23 is removed.
2 returns slightly upward under the springback effect. Therefore, the strain on the surface of the groove bottom wall 19 is reduced to ε2. At this time, the bottom wall 19 also includes a plastic deformation strain ε3, and if the caulking plate 23 is removed in this state and the restraint is released, the bottom wall 19 will have an elastic strain ε2-6.
3 will return to the initial state. This elastic strain amount ε, -63 is the strain amount that participates in stress corrosion cracking. Therefore, the conventional structure shown in FIG. 2 (i.e., H−h=
When the strain generation pattern Q) is represented by a solid line, it can be seen that elastic strain occurs on the surface of the groove bottom wall 19 in the tensile direction.

本発明によれば、第４図に示すように、コアプレート溝
部２０の外方側壁１８Ａがかしめ高さよりも小さい高さ
ｈを有し、本発明者らの実験によれば、Ｈ，ｈの関係が
Ｈ−ｈ≧０．５鋼であるならば、ひずみ発生パターンが
第５図のグラフに破線で示すようなものとなることがわ
かった。これは、かしめ作業時に発生する荷重が溝部底
壁１９に伝わらず、その表面のひずみが圧縮方向のみと
なるからである。そのため、かしめ作業終了時点におい
ても、底壁の表面に圧縮方向の弾性ひずみが生じている
ことになる。そこで、前記の弾性ひずみ量（ε２−６３
）を応力σ＝ｚ（ε２−ε３）（ここで、Ｅは縦弾性係
数）で応力値に換算し、（Ｈ−ｈ）を横軸に整理した実
験結果を第６図に示す。この図から明らかなように、Ｈ
−ｈ≧０．５鱈であれば、溝部底壁１９の表面の応力は
圧縮応力となりかつ安定するのである。したがって、応
力腐食割れの発生が著しく抑えられ、この部分での寿命
が大幅に延びることになる。According to the present invention, as shown in FIG. 4, the outer side wall 18A of the core plate groove 20 has a height h smaller than the caulking height, and according to experiments by the present inventors, H and h are It has been found that if the relationship is H-h≧0.5 steel, the strain generation pattern will be as shown by the broken line in the graph of FIG. This is because the load generated during the caulking operation is not transmitted to the groove bottom wall 19, and the strain on its surface is only in the compression direction. Therefore, even at the end of the caulking work, elastic strain in the compression direction is generated on the surface of the bottom wall. Therefore, the elastic strain amount (ε2-63
) is converted into a stress value using stress σ=z(ε2−ε3) (where E is the modulus of longitudinal elasticity), and the experimental results are shown in FIG. 6, where (H−h) is arranged on the horizontal axis. As is clear from this figure, H
If -h≧0.5, the stress on the surface of the groove bottom wall 19 becomes compressive stress and becomes stable. Therefore, the occurrence of stress corrosion cracking is significantly suppressed, and the life of this part is significantly extended.

またさらに、コアプレート１６の溝部２０の内側壁１７
および底壁１９の表面に、組付は時および使用時に内圧
、熱などの外力による不均一な応力が発生し、この応力
が断面方向に分布し、内側壁１７の応力が底壁１９の応
力よりも大きいことがわかった。したがって、第６図に
示すように、シール材２１が溝部２０の内側壁１７に接
近あるいは接触して位置している場合、より大きい応力
の発生する内側壁１７に隣接してすきまが形成され、割
れ寿命をさらに悪化させることになる。本発明では、こ
れを防ぐために、第４図に示すように、タンク２の端縁
取付部１０の内側作用面１１に溝部２０に向って突出す
る舌状ガイド２６が設けてあり、図示実施例では、この
舌状ガイド２６は内側作用面１１の内側縁、すなわち、
溝部２０の内側壁１７に隣接した部分から下方に突出し
ており、シール材２１の内側面と係合してそれの変位を
防ぐようになっている。Furthermore, the inner wall 17 of the groove portion 20 of the core plate 16
During assembly and use, non-uniform stress is generated on the surface of the bottom wall 19 due to external forces such as internal pressure and heat, and this stress is distributed in the cross-sectional direction. It turned out to be bigger than that. Therefore, as shown in FIG. 6, when the sealing material 21 is located close to or in contact with the inner wall 17 of the groove 20, a gap is formed adjacent to the inner wall 17 where a larger stress is generated. This will further worsen the cracking life. In the present invention, in order to prevent this, as shown in FIG. Then, this tongue-shaped guide 26 is located at the inner edge of the inner working surface 11, that is,
It protrudes downward from a portion of the groove 20 adjacent to the inner wall 17 and engages with the inner surface of the sealing material 21 to prevent displacement thereof.

なお、本発明を実際の製品に応用する場合、タンクの長
手方向の反り、弾性シール材の溝内での蛇行および部分
的な浮き上がり、さらにはチューブ８とコアプレート１
６の半田付は等の接合時に生じる熱ひずみによるコアプ
レートの長手方向の反り等のバラツキを含む部品の組付
けに際し、かしめ前において取付部１０の下端がコアプ
レート１６の外方側壁１８Ａの内側に挿入されるように
して、組付は性を改善するためには、（Ｈ−ｈ）の上限
値を２〜５ＷａＲ程度にすることが好ましい。In addition, when the present invention is applied to an actual product, warping in the longitudinal direction of the tank, meandering and partial lifting of the elastic sealing material in the groove, and furthermore, the tube 8 and the core plate 1
When assembling parts that include variations such as warpage in the longitudinal direction of the core plate due to thermal strain generated during soldering, etc., the lower end of the mounting part 10 is inside the outer side wall 18A of the core plate 16 before caulking. In order to improve the assembling performance by inserting the cylindrical material into the cylindrical surface, it is preferable to set the upper limit value of (H-h) to about 2 to 5 WaR.

また、市場を再現したテストにおいて、溝部底壁の表面
に発生する応力をゼロにした場合、応力腐食割れ寿命は
従来のものに比べて１０倍以上となる。ただし、実負荷
として、溝部底壁の表面に発生する応力は前述のかしめ
時に生じる応力の°ほかに内圧、熱等の外部負荷も加わ
るため、本発明の製品において、従来構造に比較して応
力腐食割れ寿命は６倍以上となることを確認した。In addition, in a test that reproduced the market, when the stress generated on the surface of the groove bottom wall was reduced to zero, the stress corrosion cracking life was more than 10 times that of conventional products. However, as an actual load, the stress generated on the surface of the groove bottom wall is not only the stress generated during caulking as described above, but also external loads such as internal pressure and heat. It was confirmed that the corrosion cracking life is more than 6 times longer.

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

第１図は本発明に係る自動車用ラジェータの正面図、 第２図は第１図のＸ−Ｘ線に沿った断面図であり、従来
の構造を示す図、 第６図は従来構造における弾性シールのずれを説明する
、第２図と同様の図、 第４図は本発明による構造を示す、第２図と同様の図、 第５図は第２図に示す従来構造における作業段階を示す
図であって、そのグラフで実線は従来構造において発生
するひずみ、破線は本発明構造において発生するひずみ
をそれぞれ示す図、第６図は本発明の構造における発生
応力と（Ｈ−ｈ）値との関係を示すグラフである。 １・・・本体、２，３・・・タンク、１０・・・タンク
端縁取付部、１１・・・内方作用面、１２・・・外方作
用面、１３・・・内方側面、１４・・・外方側面、１６
・・・コアプレート、１７・・・内方側壁、１８，１８
Ａ・・・外方側壁、１９・・・底壁、２０・・・溝部、
２１・・・弾性シール材、２２・・・つめ部、２３・・
・かしめプレート、２４・・・空間、２６・・・舌状ガ
イド。 代理人　浅　村　　　皓 外４名 　ＺFig. 1 is a front view of an automobile radiator according to the present invention, Fig. 2 is a cross-sectional view taken along the line X-X in Fig. 1, and shows a conventional structure. Figure 4 is a diagram similar to Figure 2, illustrating seal misalignment; Figure 4 is a diagram similar to Figure 2, showing a structure according to the invention; Figure 5 is a diagram illustrating the working steps in the conventional structure shown in Figure 2; In the graph, the solid line shows the strain that occurs in the conventional structure, the broken line shows the strain that occurs in the structure of the present invention, and FIG. 6 shows the stress generated in the structure of the present invention and the (H-h) value. It is a graph showing the relationship between. DESCRIPTION OF SYMBOLS 1... Main body, 2, 3... Tank, 10... Tank edge attachment part, 11... Inner action surface, 12... Outer action surface, 13... Inner side surface, 14...outer side, 16
... Core plate, 17 ... Inner side wall, 18, 18
A...Outer side wall, 19...Bottom wall, 20...Groove portion,
21... Elastic sealing material, 22... Pawl portion, 23...
・Caulking plate, 24... Space, 26... Tongue-shaped guide. Agent Asamura Akira 4 people Z

Claims (1)

【特許請求の範囲】 金属製本体の上下端に密封装着したタンクを有し、各タ
ンクが取付側の端面周縁に沿って端縁取付部を有し、ま
た、前記本体の外周面に沿ってその上、下端付近にコア
プレートが設けてあり、各コアプレートの外周縁に沿っ
て前記タンクの端縁取付部を受は入れる溝部が形成して
あり、この溝部に前記タンク端縁取付部を嵌合させたと
きに、前記端縁取付部の内、外の側壁面が溝部の側壁内
面と係合するようになっており、かつ前記端縁取付部の
内側作用面と前記溝部の内底面との間に弾性シール材が
設置してあり、さらに、コアプレート溝部の側壁外面お
よび底壁外面と係合し、タンク端縁取付部の外側作用面
に向ってかしめられてタンク端縁取付部をコアプレート
に固着するかしめプレートを包含する熱交換器において
、前記タンク端縁取付部の外向き側壁面と係合している
、前記コアプレート溝部の外側側壁の溝内底面からの高
さをｈとし、同じ溝内底面からかしめプレートのかしめ
られたタンク端縁取付部の外側作用面までの、かしめ時
における高さをＨとしたとき、（Ｈ−ｈ）≧０．５膿 となるようにすると共に、前記タンクの端縁取付部の内
側作用面に前記コアプレートの溝部に向って突出する舌
状ガイドを設け、この舌状ガイドが前記溝部内の弾性シ
ール材と係合してそれの変位を防ぐようになっているこ
とを特徴とする熱交換器。[Scope of Claims] Tanks are hermetically attached to the upper and lower ends of a metal body, each tank has an edge attachment part along the periphery of the end face on the attachment side, and an edge attachment part is provided along the outer circumference of the body. Moreover, a core plate is provided near the lower end, and a groove is formed along the outer periphery of each core plate to receive the tank edge attachment part, and the tank edge attachment part is inserted into this groove. When fitted, the inner and outer side wall surfaces of the edge attachment portion engage with the inner surface of the side wall of the groove portion, and the inner working surface of the edge attachment portion and the inner bottom surface of the groove portion are configured to engage with each other. An elastic sealing material is installed between the core plate groove and the outer surface of the side wall and the bottom wall, and is caulked toward the outer working surface of the tank edge attachment part. In a heat exchanger including a caulking plate that is fixed to a core plate, the height of the outer side wall of the core plate groove from the bottom surface of the groove, which is engaged with the outward side wall surface of the tank edge attachment portion, is h and the height from the bottom surface of the same groove to the outer working surface of the caulked tank edge attachment part of the caulking plate when caulking is H, so that (H-h)≧0.5 pus. and a tongue-shaped guide protruding toward the groove of the core plate is provided on the inner working surface of the edge attachment part of the tank, and the tongue-shaped guide engages with the elastic sealing material in the groove. A heat exchanger characterized in that it prevents displacement of the heat exchanger.