... kinds of finned tubes. 1, finned tube function: heat transfer;2, the fin-tube type: DR (extrusion type), L (winding type ... tube: carbon steel, stainless steel, copper, copper alloy, titanium and so on. 2, Fin: aluminum (extruded type or wound type), steel (wound ... , finned tube specifications: 1, base tube: OD16, OD19, OD1 ", OD38; 2, fin: OD34, OD44, OD57, OD70 (or by request).