Patent ID: 11904421
Assignee: MODINE MANUFACTURING COMPANY
Field: Machine tools (Mechanical engineering)
Classification: CPC B  F | IPC B

Claim 0:
1. A method of making a heat exchanger, the method comprising:
inserting each of a plurality of tubes into respective header slots of a header, wherein each of the plurality of tubes and the header include braze cladding;
welding ends of each of the plurality of tubes into the respective header slots on a liquid side surface of the header such that perimeters of each of the plurality of tubes are sealed into their respective header slots by welding the perimeter of each of the tubes to their respective header slot at the liquid-side surface of the header;
coupling a cover to the header to cover a liquid-side surface of the header and to cover ends of each of the plurality of tubes;
applying flux to an air-side surface of the header and to the plurality of tubes, the flux configured to remove oxidation from areas where the flux is applied, and
brazing each of the plurality of tubes to their respective header slots such that the braze cladding is melted to form a braze fillet on the air-side surface of the header between each of the plurality of tubes and the header,
wherein the welding of the ends of each of the plurality of tubes into the respective header slots on a liquid side surface of the header is configured to block flux from penetrating the header to contact (i) the liquid side surface of the header and (ii) the ends of each of the plurality of tubes; wherein coupling the cover to the header is performed before applying flux to the air-side surface of the header and to the plurality of tubes,
wherein applying flux is performed before brazing each of the plurality of tubes to their respective header slots, and
wherein the cover is removed after the step of brazing each of the plurality of tubes to respective header slots of the plurality of header slots.