Patent EP0131444A1 successfully refreshed from Google Patents.
EP0131444A1
Expired / Lapsed
EP
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Heat exchanger and method of manufacturing same
Assignee: Hitachi Ltd
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Filing: 1984-07-05
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Granted: —
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Expires: 2004-07-05
Abstract
Abstract A heat exchanger made by brazing together metal members, at least one of which is mainly made of A1 or A1 alloy is disclosed. At least one of the brazed metal members is made of brazing sheet clad with a brazing material. The brazed portions of the metal members or the whole surface of the heat exchanger are coated with a corrosion-resistant fluoride flux, for example one consisting essentially of 25-40% KF, 38-54% AIF, and 3-30% ZnF. by weight, which forms a corrosion-inhibiting metallic film.
Inventors
- 👤 Takashi Haramaki
- 👤 Katsuhiko Shiota
- 👤 Satoshi Kokura
- 👤 Takao Funamoto
- 👤 Akira Tomita
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 23:14
CPC Classifications
F; F28; F28F; F28F21/00; F28F21/08; F28F21/089; B; B23; B23K; B23K1/00; B23K1/0008; B23K1/0012; B23K35/00; B23K35/22; B23K35/34; B23K35/36; B23K35/3601; B23K35/3603; B23K35/3605; F28D; F28D1/00; F28D1/02; F28D1/04; F28D1/047; F28D1/0477; F28D1/0478; F28F1/00; F28F1/10; F28F1/12; F28F1/24; F28F1/32; F28F21/081; F28F21/084
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
74 words
A heat exchanger manufactured by connecting, by brazing, metal members of which at least one is made, or mainly made, of aluminium or aluminium alloy, characterised in that at least one of said brazed metal members is made of a sheet clad with a brazing material, and brazed portions of said metal members, or the whole surface of said heat exchanger, are coated with a corrosion-inhibiting metallic film formed from a corrosion-resistant fluoride flux.
Claim 2
Dependent Claim
74 words
A heat exchanger manufactured by connecting, by brazing, metal members of which at least one is made, or mainly made, of aluminium or aluminium alloy, characterised in that at least one of said brazed metal members is made of a sheet clad with a brazing material, and brazed portions of said metal members, or the whole surface of said heat exchanger, are coated with a corrosion-inhibiting metallic film formed from a corrosion-resistant fluoride flux.
Claim 3
Dependent Claim
19 words
A heat exchanger according to claim 1, wherein said metal members are selected from fins, tubes, and U-shaped tubes.
Claim 4
Dependent Claim
36 words
A heat exchanger according to claim 1 or claim 2, wherein at least one of said brazed metal members is made of aluminium and the other(s) is or are made of aluminium, copper, titanium and iron.
Claim 5
Dependent Claim
20 words
A heat exchanger according to any one of claims 1 to 3, wherein said fluoride flux contains ZnF 2 .
Claim 6
Dependent Claim
36 words
A heat exchanger according to any one of claims 1 to 4, wherein said fluoride flux consists essentially of 25-40% by weight KF, 38-54% by weight AlF 3 , and 3-30% by weight ZnF 2 .
Claim 7
Dependent Claim
49 words
A heat exchanger according to any one of claims 1 to 4, wherein said fluoride flux consists essentially of 25-40% by weight KF, 38-54% by weight A1F 3 , 3-30% by weight ZnF 2 , and 0.5-9% by weight of at least one of LiF, NaF, MgF and CaF.
Claim 8
Independent Claim
144 words
A method of manufacturing a heat exchanger by connecting, by brazing, metal members of which at least one is made, or mainly made, of aluminium or aluminium alloy, comprising the following steps: (a) making a heat exchanger combination by assembling a plurality of metal members, at least one of said metal members being made of a brazing sheet clad with a brazing material; (b) depositing a fluoride flux on portions of said metal members which portions are to be biased, or the whole surface of said heat exchanger combination, said fluoride flux consisting of a corrosion resistant fluoride flux which forms a corrosion-inhibiting metallic film; and (c) heating said heat exchanger combination having said fluoride flux to braze said members in a furnace in an atmosphere of a non-oxidizing gas in which the dew point of the non-oxidizing gas is not more than -15°C.
Claim 9
Independent Claim
144 words
A method of manufacturing a heat exchanger by connecting, by brazing, metal members of which at least one is made, or mainly made, of aluminium or aluminium alloy, comprising the following steps: (a) making a heat exchanger combination by assembling a plurality of metal members, at least one of said metal members being made of a brazing sheet clad with a brazing material; (b) depositing a fluoride flux on portions of said metal members which portions are to be biased, or the whole surface of said heat exchanger combination, said fluoride flux consisting of a corrosion resistant fluoride flux which forms a corrosion-inhibiting metallic film; and (c) heating said heat exchanger combination having said fluoride flux to braze said members in a furnace in an atmosphere of a non-oxidizing gas in which the dew point of the non-oxidizing gas is not more than -15°C.
Claim 10
Dependent Claim
35 words
A method according to claim 7 wherein said deposition step comprises immersing said heat exchanger combination in an aqueous solution of said fluoride flux of 6-30% by weight, and then drying said heat exchanger combination.
Claim 11
Dependent Claim
17 words
A method according to claim 7 or claim 8, wherein said fluoride flux contains ZnF 2 .
Claim 12
Dependent Claim
29 words
A method according to claim 9, wherein said fluoride flux consists essentially of 25-40% by weight KF, 38-54% by weight AlF 3 , and 3-30% by weight ZnF 2'
Claim 13
Dependent Claim
43 words
A method according to claim 9, wherein said fluoride flux consists essentially of 25-40% by weight KF, 38-54% by weight AlF 3 , 3-30% by weight ZnF 2 , and 0.5-9% by weight of at least one of LiF, NaF, MgF and CaF.
Claim 14
Independent Claim
19 words
A method according to any one of claims 7 to 11, wherein said non-oxidizing gas is N 2 .
References Cited (Backward Citations)
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