Multiple tube bank heat exchanger assembly and fabrication method

A method for fabricating a flattened tube finned heat exchanger having a first tube bank and a second tube bank, the method comprising the steps of:

• arraying a plurality of multiple tube flattened heat exchange tube assemblies in parallel spaced relationship, each heat exchange tube assembly including a first flattened heat exchange tube segment extending longitudinally, a second flattened heat exchange tube segment extending longitudinally in spaced aligned relationship with said first flattened heat exchange tube segment, and a web member extending between and connecting a trailing edge of said first heat exchange tube segment and a leading edge of said second heat exchange tube segment;
• disposing a folded fin between each pair of parallel flattened heat exchange tube assemblies to form a partially assembled fin and tube pack;
• compressing the assembled fin and tube pack between end braze bars;
• mounting a first manifold to a respective first end of each of the first flattened heat exchange segments of the plurality flattened heat exchange tube assemblies, mounting a second manifold to a respective second end of each of the first flattened heat exchange segments of the plurality of flattened heat exchange tube assemblies, mounting a first manifold to a respective first end of each of the second flattened heat exchange tube segment of the plurality of flattened heat exchange tube assemblies, and mounting a second manifold to a respective second end of each of the second heat exchange tube segments of the plurality of flattened heat exchange tube assemblies, thereby forming a final assembly;
• and
• bonding the final assembly by brazing in a brazing furnace.

A heat exchange tube assembly comprising:

• a forward heat exchange tube segment extending longitudinally;
• an aft heat exchange tube segment extending longitudinally aligned with and spaced aftward of said forward heat exchange tube segment;
• a plurality of intermediate heat exchange tube segments arrayed in spaced aligned relationship between said forward heat exchange tube segment and said aft heat exchange tube segment;
• a first web member extending between and connecting a trailing edge of said forward heat exchange tube segment to a leading edge of a first of said plurality of intermediate heat exchange tube segments;
• a second web member extending between and connecting a trailing edge of a last of said plurality of intermediate heat exchange tube segments and a leading edge of said aft heat exchange tube segment;
• and
• a plurality of intermediate web members disposed alternately between said plurality of intermediate heat exchange tube segments, each intermediate web member of said plurality of intermediate web members extending between and connecting a trailing edge of a respective one of said plurality of intermediate heat exchange tube segments to a leading edge of another respective one of said plurality of heat exchange tube segments.