Showa Denko K.k.

Showa Aluminum Corporation

Daishi Tanaka

Kazuhiko Minami

Shintaro Nakagawa

Masakazu Furuta

Yasuhiro Osame

Kazuyuki Takahashi

A method for manufacturing an aluminum heat exchanger includes the steps of: obtaining a heat exchanger tubeby forming a Zn thermally sprayed layer on a surface of an aluminum flat tube core so as to adjust Zn adhesion amount to 1 to 10 g/m; obtaining a heat exchanger core by alternatively arranging the heat exchanger tubeand an aluminum finand brazing the heat exchanger tube and the fin with end portions of the heat exchanger tube connected to aluminum headers in fluid communication; and forming a chemical conversion treatment coat (corrosion resistance coat) on a surface of the heat exchanger core by subjecting the surface of the heat exchanger core to chemical conversion treatment using at least one chemical conversion treatment agent selected from the group consisting of phosphoric acid chromate, chromic acid chromate, phosphoric acid zirconium series, phosphoric acid titanium series, fluoridation zirconium series, and fluoridation titanium series. The obtained heat exchanger has a long last good corrosion resistance and can prevent occurrence of fin detachment and pit corrosion.

Heat exchanger and method for manufacturing the same

A process for producing a flat heat exchange tube having opposed upper and lower walls and a plurality of reinforcing walls connected by brazing between the respective upper and lower walls for dividing the tube interior into parallel fluid passages. In order to strengthen the brazed connection between the reinforcing walls and the lower surface of the upper wall and to prevent the creation of a clearance space therebetween, the lower surface of the upper wall is provided in advance with longitudinally extending ridges with which the upper surfaces of the reinforcing walls come in contact to eliminate the clearances and thus insure the existence of a continuous brazed connection between each reinforcing wall and lower surface of the upper wall.

Process for producing flat heat exchange tubes

Growing community of inventors

Oyama, Japan

Daishi Tanaka