Abstract: This invention concerns finned tubes for use in heat exchanging whereby the fins have a generally T or Y shape. There is disclosed process and apparatus for making these Y and T-finned tubes whereby a smooth tube is subjected to conventional rolling process with the ends of the fins being subsequently notched into Y-fins and, if desired, subsequently flattened into T-fins. According to other embodiments of the invention the T-fins are constructed by an apparatus including an oblique surface which contacts the conventionally constructed fins causing the fins to be flattened into a general T shape.

Abstract: This invention concerns finned tubes for use in heat exchanging whereby the fins have a generally T or Y shape. There is disclosed process and apparatus for making these Y and T-finned tubes whereby a smooth tube is subjected to a rolling process with notching rollers being arranged between rolling discs. Bending rollers can be used to form Y fins and, if desired these can be subsequently flattened into T-fins.