JP4026503B2 - Manufacturing method of heat exchanger - Google Patents

Description

【図面の簡単な説明】
【図１】本発明の製造方法を適用する熱交換器の一例を示す斜視図である。
【図２】図１の構成部品である伝熱プレートの一例を示す平面図である。
【図３】ブレ−ジングシートを用いて熱交換器を製造する場合のコア部の熱媒体通路形成部位を例に採りモデル的に示した断面工程図である。
【図４】タンク部の耐内圧破壊強度が不足する場合においてバンド補強した熱交換器の斜視図である。
【図５】本発明の熱交換器の製造方法を図３に対応して表した断面工程図である。
【図６】本発明の熱交換器の製造方法を示す流れ図である。
【図７】本発明で使用するタンク形成部を厚肉塗布したプレコート材の平面図及び側面断面図
【図８】ロール塗りにより接着剤被覆金属材をつくる場合の説明図である。
【図９】フィルム状接着剤を用いて接着剤付き金属材をつくる場合の説明図である。
【符号の説明】
２０Ａ 伝熱プレート（部品）
２２ 熱交換器（製品）
２６ 心材（母材）
４２ 固状被膜（固状接着剤層）
４６ プレコート材（接着剤被覆金属材）[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a heat exchanger (condenser, evaporator, heater, etc.).
[0002]
Here, a case where a large number of heat transfer plates are bonded with an adhesive and applied to a heat exchanger in which a heat exchange passage group (core portion) and a heat medium introduction / lead-out portion (distribution / collection tank portion) are integrally formed. An example will be described, but the present invention is not limited to this.
[0003]
That is, the present invention is not limited to the one having the above configuration, and can be applied to various heat exchangers such as a multi-tube type, a double-pipe type, a spiral type, and a plate fin type (the types of heat exchangers are (See Chemical Engineering Handbook of Chemical Engineering, Maruzen, Sho 52-3-20, p1167-1174).
[0004]
[Prior art]
For example, as shown in FIG. 1, a heat medium introduction / lead-out part (tank part) 12 and a heat exchange part (core part) 14 are provided, and the tank forming part 16 and the core forming part 18 are formed by press working. A heat exchanger 22 having a structure in which a large number of heat transfer plates 20 (see FIG. 2) are joined and integrated is conventionally used as a base material (core material) of an aluminum (Al) alloy strip (rolled material). It has been manufactured using a brazing sheet obtained by clad rolling a material (Al—Si alloy) on one side or both sides (see Patent Document 1, etc.). Here, press processing has a broad meaning including roll processing.
[0005]
For example, the manufacturing method was as shown in FIG. In the illustrated example, the manufacturing process is illustrated in a model manner by enlarging and displaying one refrigerant small diameter passage (around 1 mmφ) 14 a in the core portion (heat exchange portion) 14.
[0006]
A brazing sheet (laminate plate) 28 in which a skin material (brazing material) 24 is clad (formed) on both sides or one side (in the example shown in the figure) of a core material (Al-based alloy strip) 26 is prepared (FIG. 3 (I)). . The brazing sheet 28 is produced by simultaneously coating the metal strip during hot rolling.
[0007]
Then, from the brazing sheet 28, as shown in FIG. 3, a large number of plate-like structural members (heat transfer plates) 20 in which the tank forming portion 16 and the core forming portion 18 are formed by pressing are prepared (see FIG. 3). 3 (II)). That is, as shown in FIG. 2, on the brazing sheet 28, after the tank core forming portions 16 and 18 are pressed (forming), the heat transfer plate 20 is punched out, or the blanks are punched out. The heat transfer plate (plate-shaped component member) 20 is manufactured by transfer processing that performs press processing (forming) of the core forming portions 16 and 18.
[0008]
Then, after the heat transfer plates 20 and 20 are stacked and temporarily assembled, the flux 30 is applied by electrostatic coating or the like (FIGS. 3 (III) and (IV)). At this time, the flux is an inorganic material added for the purpose of removing the oxide film on the surface of the metal material and improving the fluidity of the brazing material. In the case of an Al brazing sheet, a flux mainly composed of potassium aluminum tetrafluoride (KAlF ₄ ) is often used.
[0009]
Subsequently, in the heating furnace 32 under an N2 gas atmosphere, the brazing material is melted and brazed at a temperature lower than the melting point of the base metal, and the heat exchanger (product) 22 is obtained (FIG. 3 (V). (VI)). For example, when an aluminum brazing material is used as the brazing sheet, that is, when the core material (base material) of the plate-shaped component is Al, the heating temperature is around 600 ° C. In FIG. 3 (VI), the brazing material in the refrigerant passage hardly remains because the brazing material moves to the joint due to capillary action.
[0010]
However, according to the conventional manufacturing method as described above, a flux is required together with a brazing sheet (expensive). Further, when brazing, it is necessary to heat to around 600 ° C. in an N ₂ gas atmosphere. While the energy cost increased, a high power electric furnace with high airtightness was required.
[0011]
In addition, when using a flux containing KAlF ₄ as a main component, an Al-Mg alloy (for example, A5000 series: A5052, A5182, etc.) having a relatively high strength compared to other Al alloys. It could not be used as a base material. This is because KAlF ₄ reacts with Mg and a high melting point substance (KMgF ₃ or the like) is generated, so that the flux function (oxide film removing action) is lowered and the fluidity of the brazing material is inhibited.
[0012]
Furthermore, since the brazing heating temperature is relatively high at around 600 ° C., Al—Cu—Mg based (A2024, etc.) low melting point Al based alloys and Al based processing where work hardening is restored by high temperature heating. The use of a hardener (such as H14) as a base material was also restricted.
[0013]
Therefore, the selection range as a base material of the Al-based alloy is narrow, and there has been a problem of changing to a joining method in which these high-strength Al-based alloys necessary for thinning can be used.
[0014]
And when it is manufactured with a thin material of conventional strength (tensile strength of 180 MPa or less, Al material of 0.15 mmt or less; for example, A3003), it is difficult to obtain a predetermined pressure resistance in the tank part, and a post-process after preparing the heat transfer plate It was necessary to incorporate a tank reinforcement process. The heat medium pressure receiving inner diameter of the tank part is much larger than that of the core part (for example, the latter is 1 mmφ with respect to the former 10 to 15 mmφ), and the tank part is required to have a higher internal pressure fracture resistance than the core part.
[0015]
Therefore, as shown in FIG. 4, after brazing (assembling and joining), a fastening band (aluminum band) 33 is fastened to the tank portion 12 in the longitudinal direction (vertical direction), or an adhesive is applied to the surroundings again. It was reinforced by heat curing. In heating at a brazing temperature (about 600 ° C.), even an epoxy-based adhesive is thermally deteriorated, and it is impossible to combine the heating process.
[0016]
As a joining method other than brazing, there are welding, friction welding, adhesion (agent), and the like.
[0017]
However, since welding and friction welding involve melting of the base material and pressurization with a high load, it is necessary for heat exchangers that need to join many parts simultaneously using thin materials. Is unsuitable. On the other hand, with regard to adhesion (agent), there is a possibility that a large number of thin-walled materials can be simultaneously joined at a low temperature (for example, 250 ° C. or lower).
[0018]
For example, Patent Documents 2 and 3 describe a technique in which an adhesive is applied to a constituent member (of a heat exchanger) after pressing and assembled and integrated.
[0019]
However, to apply the adhesive uniformly to a large number of components having minute irregularities after press working, it is necessary to remove excess adhesive by blowing high-pressure air or the like as described in Patent Document 2. Yes and troublesome. Also in Patent Document 2, it is estimated that the same problem occurs.
[0020]
Patent Documents 4 and 5 describe a technique in which an adhesive is applied at the material stage before pressing and then cured and bonded.
[0021]
However, since a normal adhesive is liquid and has adhesiveness, it is estimated that problems such as adhesion to a contact object (handling material, tool) occur during press working.
[0022]
[Patent Document 1]
JP-A-11-287580 [Patent Document 2]
Japanese Patent Laid-Open No. 64-58990 [Patent Document 3]
JP-A-2-115288 [Patent Document 4]
JP-A-1-273634 [Patent Document 5]
JP-A-2002-243395 [0023]
[Problems to be solved by the invention]
In view of the above, an object of the present invention is to provide a method of manufacturing a heat exchanger that does not cause problems caused by adhesive bonding instead of brazing (brazing material bonding).
[0024]
Still another object of the present invention is to provide a heat exchanger that does not need to incorporate a reinforcing step in a part that requires a resistance to internal pressure fracture strength as compared with other parts such as a tank part, after the heat transfer plate preparation process. It is to provide a manufacturing method.
[0025]
[Means for Solving the Problems]
As a result of diligent efforts to solve the above-mentioned problems, the present inventors have come up with a method for manufacturing a heat exchanger having the following configuration.
[0026]
A method of manufacturing a heat exchanger that is a substantially bonded structure comprising:
An adhesive-coated metal material (pre-coating material) is prepared by covering a metal base material with a non- sticky solid coating made of an epoxy-based thermosetting adhesive in a B state, entirely or partially. A precoat material preparation step,
A component preparation step of forming a component by pressing the precoat material, and
After the temporary assembly of the constituent members, an assembly / bonding step of completely curing (crosslinking) the uncured solid film in a C state in a heating atmosphere of 250 ° C. or lower is characterized.
[0027]
In the present invention, the coating of the adhesive-coated metal material (pre-coating material) used as the material for the heat exchanger is a solid coating and has substantially no adhesiveness, and there is a problem in handling in press processing and assembly in the subsequent process. Does not occur. That is, problems such as adhesive adhesion due to interference and contact with other members do not occur.
[0028]
Therefore, it becomes easy to manufacture a heat exchanger by adhesive bonding, and naturally, when manufacturing by brazing, there is a limitation on the degree of freedom of metal selection, and further, a special for making a high temperature N ₂ atmosphere around 600 ° C. The equipment is also unnecessary. Further, since the heating atmosphere is 250 ° C. or lower, there is almost no possibility that the metal base material is affected by heating. Furthermore, since the thermosetting adhesive is an epoxy-based adhesive, it is highly versatile as a metal adhesive, and it is easy to obtain one that meets the required characteristics.
[0029]
In the pre-coating material preparation step, the productivity of the pre-coating material is good by forming an adhesive layer by placing an uncured solid film adhesive on a metal base material and bonding it with a pressure roller. is there. That is, when this method is employed, productivity is better than when a liquid adhesive is applied and then dried or cured to form an uncured solid (so-called B state) adhesive layer.
[0032]
And the manufacturing method of the said heat exchanger is provided with the heat-medium introduction / derivation | leading-out part (tank part) and the heat exchange part (core part), and many sheets by which the tank formation part and the core formation part were formed by press work In the method of manufacturing a heat exchanger having a structure in which the plate-shaped component members (heat transfer plates) are laminated and integrated, it is desirable to use the manufacturing method of (1) or (2) below.
[0033]
(1) on one side or both sides of the metal plate (metal base material), the uncured solid film having no tackiness of epoxy-based thermosetting adhesive B state, the thick tank construction site than other sites A pre-coating material preparation process for preparing an adhesive-coated metal material (pre-coating material) to be formed by applying to a state;
A heat transfer plate preparation step of forming a heat transfer plate from the pre-coating material by pressing, and
After the heat transfer plate is temporarily assembled, an assembly / bonding step of completely curing (crosslinking) the uncured solid film into a C state in a heating atmosphere of 250 ° C. or lower is characterized.
[0034]
(2) Adhesive that forms an uncured solid coating having a uniform thickness on the entire surface, which is made of an epoxy-based thermosetting adhesive in a B state, on one or both surfaces of a metal plate (metal base material) Coating metal material (pre-coating material) preparation process,
A heat transfer plate preparation step of forming a heat transfer plate by pressing a precoat material; and
After the heat transfer plate is temporarily assembled, a reinforcing adhesive is applied to the periphery of the tank portion, and then an assembly and bonding step of completely curing the uncured solid film in a C state in a heating atmosphere of 250 ° C. or lower is included. A method for producing a heat exchanger, characterized in that
[0035]
As in (1) and (2) above, the tank part is formed in a single heat-curing step by forming the uncured solid film (adhesive layer) in the tank component part thickly before heat-curing. Only the thickened and easily deformable tank can be thickened with an adhesive to reinforce the strength.
[0037]
Moreover, it is preferable that a metal plate material is an aluminum-type plate material which usually shows a thickness of 0.15 mmt or less and a tensile strength (JIS Z 2241) of 180 MPa or more. This is to contribute to the reduction in size and weight of the heat exchanger.
[0040]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. Here, as in the above-described example, as shown in FIG. 1, when the structure (the heat exchanger (product) 22) including the tank portion 12 and the core portion 14 and joining and integrating the heat transfer plate 20 is manufactured. Will be explained. As shown in FIG. 2, the heat transfer plate 20 is formed by pressing a tank forming portion 16 and a core forming portion 18.
[0041]
The heat exchanger of the present embodiment is a method for manufacturing a heat exchanger that is a substantially bonded structure. Here, the substantial bonded structure is sufficient if the main components (heat exchange portion, etc.) of the heat exchanger components are adhesively bonded, and accessory components such as a cover portion and a bracket can be welded or detached. It means that a mechanical coupling such as a screw clip may be included.
[0042]
And one embodiment of the manufacturing method of this invention consists of the following (1) precoat material preparation process, (2) heat-transfer plate (component member) preparation process, and (3) assembly joining process (refer FIG. 5 and 6). ).
[0043]
(1) Precoat material preparation step:
An uncured solid film (adhesive layer) 42 made of a thermosetting adhesive in a B state (uncrosslinked) is provided on one side or both sides (one side in the illustrated example) of the metal plate material (metal base material) 26, and the tank components 12A is applied thicker than the core portion 14A to prepare an adhesive-coated metal material (precoat material) 46 (see FIG. 7). In addition, the dashed-two dotted line of FIG. 7 is a cutting position of a blank thru | or a heat-transfer plate.
[0044]
Here, as the metal base material, Al-based metal is usually used from the viewpoint of heat transfer and weight reduction, but depending on the required characteristics of the heat exchanger, Cu-based, iron-based, Mg-based, Ti-based, etc. It may be a metal material.
[0045]
The Al-based metal includes Al and an Al-based alloy. When the Al alloy is used as a heat exchanger material, for example, A2000-based (Al-Cu-based), A3000-based (Al-Mn-based), A5000-based (Al-Mg system), A6000 system (Al-Mg-Si system), A7000 system (Al-Zn system), etc. can be used. In particular, in the case of the heat transfer plate, from the viewpoint of weight reduction, etc., high-strength Al alloys such as A5052, A5182 (Al-Mg-based), A2017 (Al-Cu-Mg-based), A3003 (Al-Mn-Cu) are used. Etc.) is desirable. Here, the material symbol is a JIS symbol.
[0046]
The metal plate is a rolled material, and the thickness (wall thickness) of the metal plate is usually 0.02 to 1 mm, preferably 0.05 to 0.5 mm in the case of Al. From the viewpoint of weight reduction, as described later, it is desirable to use a material having a wall thickness of 0.15 mmt or less and a tensile strength (JIS Z 2241) of 180 MPa or more. However, in the present embodiment where the internal pressure fracture resistance is required, in the present embodiment, it is necessary to provide reinforcement measures as will be described later.
[0047]
The thermosetting adhesive to be used is not particularly limited as long as an uncured solid (B state) can be obtained or manufactured as the thermosetting adhesive for metal structure.
[0048]
For example, solid epoxy, epoxy / phenolic, nylon / epoxy, nitrile / epoxy, polyvinyl formal / phenolic, nitrile rubber / phenolic, etc. can be used. 353). Of these, the former four epoxy-based ones are preferable because they are versatile and can select various properties. In particular, from the viewpoint of heat resistance, an epoxy / phenolic material excellent in thermal stability is desirable.
[0049]
The coating thickness of the uncured solid coating (adhesive layer) 42 is such that the tank constituent part 12A is thicker than the core constituent part 14A (see FIG. 7). Here, the core component (general part) is usually 5 to 100 μm, preferably 10 to 50 μm, and the tank part is thicker, usually 10 to 200 μm, preferably 40 to 80 μm.
[0050]
The method for forming the coating is arbitrary, such as roller coating, brush coating, spray coating, and dip coating. From the viewpoint of obtaining a stable coating thickness, usually, as shown in FIG. 8, the amount of adhesion (film thickness) by the doctor roll 36 on the surface of the rolled material (base material: core material) 26 conveyed on the backup roll 34. It is applied by the coating roll 38 while adjusting. Supply of the liquid adhesive 40A to the coating roll 38 is performed by a pickup roll (not shown) or the like.
[0051]
And, in order to apply the adhesive to the tank component part 12 thickly, it may be applied twice (overcoated), but the end corresponding to the tank forming part of the doctor roll 36 is made small in diameter, After increasing the gap between the roll 36 and the coating roll 38 or applying the required coating thickness to the tank formation site, scrape the adhesive at the core formation site with a doctor blade or the like to obtain the required coating thickness at the core formation site. It may be formed. Furthermore, it is also possible to apply an adhesive to the tank constituent part thickly using an extrusion die.
[0052]
When a solid (B state: uncrosslinked) film adhesive is used, as shown in FIG. 9, a film is formed on the surface of the rolled plate (base material) 26 conveyed on the backup roll 34A. An uncured solid coating 42 is formed by pressure bonding with a pressure roll (pressure roller) 35 that is slightly heated (100 ° C.) as necessary while the adhesive 40A is placed thereon. The film adhesive 40A is made by casting and drying.
[0053]
And when forming a thick coating film part using the film-like adhesive 42A, after pressure-bonding the film-like adhesive to the whole base material with the pressure-contacting roll 35, the pressure-contacting roll 35 made into a tape shape with a predetermined width. The film adhesive 42A is pressure-bonded.
[0054]
(2) Heat transfer plate preparation process:
The heat transfer plate 20A (see FIG. 2) is formed from the precoat material 46 by pressing.
[0055]
That is, (1) the tank / core forming portions 16 and 18 are pressed (forming) and then the heat transfer plate 20A is punched out, or (2) the blank is punched out and then the tank / core forming portion is pressed. 16 and 18 are manufactured by transfer processing which performs press processing (forming).
[0056]
At this time, since the adhesive layer is an uncured solid layer having substantially no tackiness, the adhesive is not attached even if the precoat material interferes with or contacts with other parts, and the handling property is good. It is.
[0057]
(3) Assembly connection process:
After the heat transfer plate 20A is temporarily assembled, an assembly / bonding step in which the uncured film (adhesive layer) is completely cured (crosslinked) in the C state in a heated atmosphere. At this time, the temperature of the heated atmosphere affects the base metal. Do not give 250 ° C or less. Although it changes with kinds of adhesives, in the case of an epoxy type, heat-curing conditions are usually 180-220 ° C. × 15-45 min. If the heating temperature is too low, the adhesive will cure slowly, which is undesirable from a productivity standpoint. If the heating temperature is too high, the adhesive polymer will not only affect the metal matrix, but also the heat effect (thermal degradation). It is easy to receive.
[0058]
At this time, the heating atmosphere does not need to be as high as about 600 ° C. in the N ₂ atmosphere as in the case of brazing. That is, a high-power electric heating furnace that can enclose N ₂ is unnecessary, and a general-purpose heating furnace can be used. Moreover, in this heat-hardening process, the atmospheric heating degreasing of the processing oil used at the time of press work can also be used.
[0059]
In the above, the coating thickness in the tank constituent part 12 of the uncured solid coating (adhesive layer) 42 was formed thicker than the core constituent part, and the tank part was reinforced, An uncured solid coating 42 may be formed uniformly, and after the heat transfer plate 20A is temporarily assembled, a reinforcing adhesive may be applied to the outer periphery of the tank portion 12 before the heat curing step (FIG. 6, two-dot chain line). reference). The adhesive used in this case can be the liquid adhesive or film adhesive used for the above-mentioned solid film formation, but since it is just before heat curing, it is usually in the A state based on liquid epoxy or the like It is desirable to use an adhesive. The application method is preferably dip coating, spray coating, brush coating or the like.
[0060]
【Example】
Examples carried out together with comparative examples in order to confirm the effects of the invention will be described below.
[0061]
Using the aluminum-based rolled material of each plate thickness and material shown in Table 1, the examples were manufactured in the process shown in FIG. 1 and according to the conditions shown in FIG. 4, respectively.
[0062]
The results are shown in Table 1, and the heat exchanger of each example of the present invention can achieve weight reduction as compared with the heat exchanger of the comparative example. If the thickness is increased, it will be understood that a separate process for reinforcing the tank part is not necessary in a subsequent process after preparing the heat transfer plate. In addition, when a heat exchanger (heat transfer plate) is manufactured with an A3000-based brazing sheet, the required pressure (3 Mpa or more) is shown at a thickness of 0.4 mm for the internal pressure fracture resistance in the tank (comparison) Example 1) The required strength cannot be satisfied with a plate thickness of 0.20 mm (Comparative Example 2). For this reason, it turns out that the reinforcement | strengthening measure by Al band or the adhesive application for a reinforcement is required (comparative examples 3 and 4).
[0063]
[Table 1]

[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of a heat exchanger to which a manufacturing method of the present invention is applied.
2 is a plan view showing an example of a heat transfer plate that is a component of FIG. 1. FIG.
FIG. 3 is a cross-sectional process diagram schematically showing a heat medium passage forming portion of a core portion as an example when a heat exchanger is manufactured using a brazing sheet.
FIG. 4 is a perspective view of a heat exchanger reinforced with a band when the internal pressure fracture resistance of the tank portion is insufficient.
FIG. 5 is a cross-sectional process diagram corresponding to FIG. 3 for illustrating a method of manufacturing a heat exchanger according to the present invention.
FIG. 6 is a flowchart showing a method for manufacturing a heat exchanger according to the present invention.
FIG. 7 is a plan view and a side cross-sectional view of a precoat material in which a tank forming portion used in the present invention is thickly coated. FIG.
FIG. 9 is an explanatory diagram in the case of producing a metal material with an adhesive using a film adhesive.
[Explanation of symbols]
20A Heat transfer plate (parts)
22 Heat exchanger (product)
26 Heartwood (base material)
42 Solid coating (solid adhesive layer)
46 Pre-coating material (adhesive coated metal material)

Claims (5)

A method of manufacturing a heat exchanger that is a substantially bonded structure comprising:
An adhesive-coated metal material (pre-coating material) is prepared by covering a metal base material with a non- sticky solid coating made of an epoxy-based thermosetting adhesive in a B state, entirely or partially. A precoat material preparation step,
A component preparation step for forming the component by press working the precoat material, and
A method of manufacturing a heat exchanger, comprising: an assembling and coupling step of completely curing (crosslinking) the uncured solid coating film in a C state in a heating atmosphere of 250 ° C. or less after provisional assembly of the constituent members.   2. The pre-coating material preparing step, wherein the uncured solid film adhesive is placed on a metal base material and bonded by a pressure roll to form the uncured solid coating. The manufacturing method of the heat exchanger of description. A large number of plate-like components (heat transfer plates) each having a heat medium introduction / lead-out part (tank part) and a heat exchange part (core part), and in which the tank forming part and the core forming part are formed by pressing. In a method of manufacturing a heat exchanger having a structure in which the layers are integrated together,
On one or both sides of the metal plate (metal base material) coating, the uncured solid film having no tackiness of epoxy-based thermosetting adhesive B state, the tank construction sites thicker than the core component parts A precoat material preparation step for preparing an adhesive-coated metal material (precoat material) to be formed,
A heat transfer plate preparation step of forming a heat transfer plate by press working from the precoat material, and
A method of manufacturing a heat exchanger, comprising: an assembling and coupling step of completely curing (crosslinking) the uncured solid film in a C state in a heating atmosphere of 250 ° C. or less after the heat transfer plate is temporarily assembled. A large number of plate-like components (heat transfer plates) each having a heat medium introduction / lead-out part (tank part) and a heat exchange part (core part), and in which the tank forming part and the core forming part are formed by pressing. In a method of manufacturing a heat exchanger having a structure in which the layers are integrated together,
Adhesive-coated metal material (pre-coating material) that forms an uncured solid coating that does not have adhesive properties on the entire surface of one or both surfaces of a metal plate (metal base material) made of an epoxy-based thermosetting adhesive in the B state Preparation process,
A heat transfer plate preparation step of forming a heat transfer plate by pressing the precoat material; and
After temporarily assembling the heat transfer plate, a reinforcing adhesive is further applied to the peripheral surface of the tank, and then the uncured solid coating is completely cured in a C state in a heating atmosphere of 250 ° C. or lower. The manufacturing method of the heat exchanger characterized by including. The method for manufacturing a heat exchanger according to any one of claims 1 to 4 , wherein the metal plate is an aluminum plate having a wall thickness of 0.15 mmt or less and a tensile strength (JISZ 2241) of 180 MPa or more.

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