Heat exchanger tube with concave-shaped end and method of manufacturing a heat exchanger tube with concave-shaped end

A method of making a heat exchanger tube with a concave-shaped end for use in a heat exchanger, comprising the steps of:

• a) providing a tube;
• b) removing opposite portions of the tube by cutting a disc-shaped portion with a generally smoothly-curving periphery along a major portion of the width of said tube to form a tube end having two extended portions, each extended portion opposite the other around the periphery of said tube end, and two shorter portions, each shorter portion between said two extended portions and opposite each other around the periphery of said tube end, the tube end being shaped to conform to a cross-section of a header wall when viewed in a direction normal to a longitudinal axis of the tube and in a direction along the shorter portions between the extended portions;
• and
• c) inserting and securing said tube end within an opening in the header wall of a heat exchanger manifold to form a tube-to-header joint such that said tube end does not protrude beyond said header wall opening into said manifold and such that said two extended portions are oriented perpendicular to fluid flow direction along a length of the manifold and said two shorter portions are oriented in the direction of said fluid flow to reduce interference with fluid flow within the manifold as fluid flows past the tube end shorter portions between the extended portions along the length of the manifold.

A method of making a heat exchanger assembly comprising the steps of:

• a) providing an inlet manifold including an elongated header portion having a wall, the manifold having a length with fluid flow direction along the length thereof, said manifold having at least one inlet for passage of fluid into the manifold and having a plurality of openings in the wall of the header to receive a tube;
• b) providing a tube for carrying fluid between the inlet manifold and an outlet manifold, said tube having a tube end having two extended portions, each extended portion opposite the other around the periphery of said tube end, and two shorter portions, each shorter portion between said two extended portions and opposite each other around the periphery of said tube end, the tube end being shaped to conform to a cross-section of the header wall when viewed in a direction normal to a longitudinal axis of the tube and in a direction along the shorter portions between the extended portions;
• and
• c) inserting and securing said tube end within said inlet manifold header wall opening to form a tube-to-header joint, such that said tube end does not protrude beyond said header wall opening into said manifold and such that said two extended portions are oriented perpendicular to said fluid flow direction along the length of the manifold and said two shorter portions are positioned to not protrude beyond said header wall opening into said header and oriented in the direction of said fluid flow direction to reduce interference with fluid flow within the manifold as fluid flows past the tube end shorter portions between the extended portions along the length of the manifold, said tube extending between the inlet manifold and the outlet manifold.

A method of making a heat exchanger assembly comprising the steps of:

• a) providing an inlet manifold including an elongated header portion having a wall, the manifold having a length with fluid flow direction along the length thereof, said manifold having at least one inlet for passage of fluid into the manifold and having a plurality of openings in the wall of the header to receive a tube;
• b) providing a tube for carrying fluid between the inlet manifold and an outlet manifold, said tube having a tube end having two extended portions, each opposite the other around the periphery of said tube end, and two shorter portions, each between said two extended portions and opposite each other around the periphery of said tube end, the tube end being shaped to conform to a cross-section of the header wall when viewed in a direction normal to a longitudinal axis of the tube and in a direction along the shorter portions between the extended portions;
• c) providing resilient grommets having a body portion for extending within said header wall opening;
• d) inserting said resilient grommets into said inlet manifold header wall openings;
• and
• e) inserting and securing said tube end into said header wall opening and through said grommet body portion to seal said tube end to said header wall opening, such that said tube end does not protrude beyond said header wall opening into said manifold and such that said two extended portions are oriented perpendicular to said fluid flow direction along the length of the manifold and said two shorter portions are positioned to not protrude beyond said header wall opening into said header and oriented in the direction of said fluid flow direction to reduce interference with fluid flow within the manifold as fluid flows past the tube end shorter portions between the extended portions along the length of the manifold, said tube extending between the inlet manifold and the outlet manifold.