A process for making heat exchanger tubes comprises the operating steps of cutting a piece of sheet, subjecting the piece of sheet (3) to a forming step to obtain a plurality of first elements (8, 9) which mirror one another, and bending the piece of sheet (3) to create a tubular element (1) which has two flat walls (4) with the raised elements (8, 9) on them, the flat walls being opposite one another and joined by two connecting walls (5), and; the bending step substantially joining the lateral edges (7) to one another; and welding the lateral edges (7) to close the tubular element (1). The first raised elements (8) having an extended shape according to their main direction of extension. Those of the rows closest to the central axis (X) are made in such a way that their main direction of extension is set at an angle to the central axis (X) and to a direction perpendicular to it, while those of the rows closest to the lateral edges (7) are made in such a way that their main direction of extension is set at an angle to the central axis (X) and to a direction perpendicular to it, on the opposite side relative to the first raised elements (8) of the rows closest to the axis (X). The claims also relate to a tube obtained in this way.