Patent ID: 6196442
Filing Date: 2001-03-06
Classification: B23K

Abstract:
A method for brazing a plurality of aluminum components of different compositions and masses to an aluminum tube member in a continuous furnace, comprising the steps of:providing an aluminum tube member having a plurality of apertures of predetermined diameter through a side thereof;providing a plurality of aluminum components to be joined to the tube member, each of the components including a stud member projecting therefrom having a diameter of tapering cross-section such that said diameter tapers from a diameter smaller to a diameter larger than the diameter of said tube member apertures;forming a tube preassembly by fitting the plurality of components onto the aluminum tube member by inserting a stud member of a component into a predetermined tube member aperture until an interference fit therebetween is obtained establishing a component-to-tube connection;applying a first brazing paste material to preselected ones less than all of the component-to-tube connections of said tube preassembly;applying a second brazing paste material to other preselected ones of the component-to-tube connections, said second brazing paste material having a composition different than said first brazing paste material;heating a furnace to a predetermined temperature of at least 580.degree. C.;establishing an atmosphere of predetermined composition in said furnace under equilibrium conditions in the absence of the tube preassembly;passing said tube preassembly having said first and second brazing paste materials thereon through said atmosphere in said furnace at a predetermined rate; andpassing said tube preassembly through a cooling region in said furnace to cause said brazing paste materials to solidify and to form a tube assembly.