Flat tubes for use with heat exchanger and manufacturing method thereof

摘要

The height of a bead opposing a joint where side edges of a plate are to be joined is set to be smaller than the height of a bead which does not oppose the joint by the thickness of the plate. Further, lands are provided between the beads and protrude from either the tube surface or the tube surface toward the inside of the main tube unit, and flow gaps are formed through which the heat-exchange medium flows over the lands.