Method for Producing a Folded Flat Tube

The method according to any of the preceding claims, characterized in that the flat tube (1) is folded such that a single-layered middle web (3) is obtained, which has first brazing point (4a) or first gluing point (5a) on a first side (14), and a second brazing point (4b) or second gluing point (5b) on an opposite second side (15) of the middle web (3).

The method according to any of the preceding claims, characterized in that the flat tube (1) is folded such that a large surface area contact is obtained between the middle web (3) and the edges (6, 7) that are to be brazed or glued at the brazing points (4, 4a, 4b) or gluing points (5, 5a, 5b).

A flat tube (1) produced according to the method in any of the preceding claims.

A method for the production of a folded flat tube, wherein

• the flat tube is folded, and flux is applied exclusively from an outside of the folded flat tube, wherein a geometry of the folded flat tube is such that the flux is present at predefined brazing points in a subsequent brazing process, but not, or only to a limited extent, in an interior portion of the flat tube, or
• the flat tube is folded, and adhesive is applied exclusively from an outside of the folded flat tube, wherein the folding geometry of the folded flat tube is such that the adhesive is present at predefined gluing points in a subsequent gluing process, but not, or only to a limited extent, in the interior portion of the flat tube.