Abstract: An aluminum flat tube for a heat exchanger is fabricated from an aluminum strip-shaped material which is structured by a core material coated with a sacrificial anode material on the inner face thereof and coated with a brazing filler metal on the outer face thereof by bending in the width direction to form a nearly B-shaped flat cross section. To improve the corrosion resistance of the inner face of the tube, the both edge parts of the strip-shaped material in the width direction thereof are bent inward into the tube so as the front end edge of the edge part to become apart from the flat inner face of the tube.

Abstract: The present invention provides an EGR cooler that is easy to manufacture and can accelerate heat exchange. Round in section tubes are plastically deformed in one plane crossing centerlines thereof such that corrugated exhaust gas flow paths are formed inside the tubes.

Abstract: An aluminum-made heat exchanger including a flat tube is formed by, using an aluminum strip-shaped material coated with a brazing metal on the outer surface of a core metal and coated with a sacrificial anode material at the inner surface side thereof, bending the strip-shaped material in the width direction thereof, wherein many flat tubes are diposed parallel with each other and joined using a flux in a furnace. In order to provide the aluminum-made heat exchanger capable of being satisfactorily brazed and a high strength after brazing, the brazing metal is of an Al—Si alloy, core metal is an Al—Si alloy including Si of 0.4 to 1.2% by weight, and the sacrificial anode material is of an Al—Mg—Zn alloy including Mg of 0.3 to 0.75% by weight.

Abstract: A flat tube having a nearly B-like shape or the like in cross section, which has one or more partitions therein, and is coated with a brazing metal on the outer surface thereof, is provided. In the top portion of the turned-up portion constituting the partition, there are formed many slits, in order to provide the conditions that satisfy both of the brazing performance and an increase of working accuracy of the flat tube, which slits allow the brazing metal to enter up to the top portion of the turned-up portion, wherein the length “c” of the slit is 2 mm to 15 mm; the distance “e” between the edges of the neighboring slits is 3 mm to 10 mm; and “e/c” is 0.6 or more.

Abstract: The present invention provides an EGR cooler that is easy to manufacture and can accelerate heat exchange. Round in section tubes are plastically deformed in one plane crossing centerlines thereof such that corrugated exhaust gas flow paths are formed inside the tubes.