Heat exchanger tube

• US 20050006065A1
• Filed: 04/14/2004
• Published: 01/13/2005
• Est. Priority Date: 05/06/2003
• Status: Abandoned Application

• Current Assignee: Mitsubishi Aluminum Company Limited (Mitsubishi Materials Corporation)
• Original Assignee: Mitsubishi Aluminum Company Limited (Mitsubishi Materials Corporation)
• Inventors: Watanabe, Akira, Katsumata, Masaya, Hyogo, Yasunori
• Application Number:
  US10/823,563
• Publication Number:
  US 20050006065A1
• Time in Patent Office: Days
• US Class Current: 165/133
• CPC Class Codes: B23K 1/0012 Brazing heat exchangers
• CPC Class Codes: B23K 1/203 Fluxing, i.e. applying flux onto surfaces
• CPC Class Codes: B23K 2101/06 Tubes
• CPC Class Codes: B23K 2101/14 Heat exchangers
• CPC Class Codes: B23K 2101/34 Coated articles , e.g. plated or painted; Surface treated articles
• CPC Class Codes: B23K 2103/10 Aluminium or alloys thereof
• CPC Class Codes: B23K 35/286 Al as the principal constituent
• CPC Class Codes: B23K 35/3603 Halide salts
• CPC Class Codes: B23K 35/3605 Fluorides
• CPC Class Codes: F28F 1/126 consisting of zig-zag shaped fins F28F1/105 takes precedence
• CPC Class Codes: F28F 19/06 of metal
• CPC Class Codes: F28F 21/084 from aluminium or aluminium alloys
• CPC Class Codes: F28F 2255/16 extruded

Abstract

A heat exchanger tube having higher corrosion resistance is provided. The heat exchanger tube includes an Al alloy extruded tube, and a flux layer containing a Si powder and a Zn-containing flux formed on the external surface of the Al alloy extruded tube, wherein an amount of the Si powder applied to the Al alloy extruded tube is not less than 1 g/m² and not more than 5 g/m², and an amount of the Zn-containing flux applied to the Al alloy extruded tube is not less than 5 g/m² and not more than 20 g/m².

Claims

1. A heat exchanger tube comprising an Al alloy extruded tube, and a flux layer containing a Si powder and a Zn-containing flux formed on an external surface of the Al alloy extruded tube, wherein

an amount of the Si powder applied to the Al alloy extruded tube is not less than 1 g/m and not more than 5 g/m², and an amount of the Zn-containing flux applied to the Al alloy extruded tube is not less than 5 g/m² and not more than 20 g/m².

2. The heat exchanger tube according to claim 1, wherein the Zn-containing flux contains at least one Zn compound selected from ZnF₂, ZnCl₂ and KZnF₃.

3. The heat exchanger tube according to claim 1 or 2, wherein a maximum particle size of the Si powder is 30 μ

m or smaller.

4. The heat exchanger tube according to any one of claims 1 to 3, wherein the Al alloy extruded tube contains 0.5% by weight or more and 1.0% by weight or less Si, 0.05% by weight or more and 1.2% by weight or less Mn, with a balance being Al and inevitable impurities.