Method for producing a brazing wire and resulting brazing wire
A method for producing a brazing wire consists of unwinding a solid metal or metal alloy wire, of circular or substantially circular cross-section and subjecting the wire to a stamping operation between rotating rollers, the periphery of which respectively having a die for receiving the full wire and a punch capable of deforming the wire and of generating a U-shaped cross-section across substantially the entire original diameter of the wire. The method also consists of filling the volume defined by the U using brazing flux or pickling flux in a powder or paste form and closing the arms of the U, after filling of the volume with the flux, one on top of the other with the end of one of the arms of the U overlapping the other. The method also consists of calibrating and shaping the resulting wire, according to the desired diameter and cross-section.
1 . A method for formation of a brazing wire, comprising:
first, unwinding a solid metal or metal alloy wire, of circular cross-section;
subjecting said wire to a stamping operation between rotating rollers, a periphery of said rollers respectively having a die for receiving said wire and a punch capable of deforming the wire and of generating a U-shaped cross-section of said wire across an entire original diameter of said wire;
filling a volume defined by the U-shaped cross-section by means of a brazing flux or pickling flux in powder or paste form;
closing arms of the U-shaped cross-section, after the step of filling of the volume with the brazing flux or with the pickling flux, such that a first arm of the arms of the U-shaped cross-section is disposed on top of a second arm of the arms of the U-shaped cross-section with an end of the first arm overlapping an end of the second arm;
calibrating and of conforming the wire now filled with the brazing flux or with the pickling flux, according to a desired diameter and cross-section,
wherein the stamping of the metal or metal alloy wire is performed so as to define a differentiated deformation of said wire between a center or middle of the wire and the ends of the first and second arms of the U-shaped cross-section, so as to define a cored brazing wire having an outer metal or metal alloy wall having a constant thickness.
2 . A method for the forming of a brazing wire according to claim 1 , wherein, between the step of unwinding of the solid wire and the stamping operation, a rectifying step is performed so as to obtain a perfectly linear wire.
3 . A method for the forming of a brazing wire according to claim 1 , wherein, after the stamping operation, the wire undergoes by means of a second die a shaping operation before the step of filling, intended to adjust a dimension of the U-shaped cross-section according to the desired diameter.
4 . A method for the forming of a brazing wire according to claim 1 , wherein the filling of the volume with a brazing flux or pickling flux is performed by running of said wire through a reservoir of the brazing flux or the pickling flux in the power or paste form, and then shaving at a level at an end of the wire.
5 . A method for the forming of a brazing wire according to claim 4 , wherein the reservoir is subjected to vibrations.
6 . A method for the forming of a brazing wire according to claim 1 , wherein the filling of the volume by the brazing flux or pickling flux is controlled by means of a camera or any equivalent means measuring an effective height of the brazing flux or pickling flux in the volume.