Flat tube brazing method useful in automobile vehicle e.g. radiator cooling motor, comprises depositing layer of brazing flow on external and internal side of tube section during formation of tube and after assembling of heat exchanger

The flat tube brazing method useful in an automobile vehicle such as radiator cooling motor and air-conditioning evaporator, comprises depositing a layer of brazing flow on an external and an internal side of a flat tube (10) section during a formation of the tube and after assembling of a heat exchanger. The flat tube is brazed with spacers (20), which are disposed in an exterior and an interior of the tubes. The deposition step is carried out in a form of a continuous or discontinuous row, and is carried out using a syringe, a dosing valve, an engraved roller and a paintbrush. The flat tube brazing method useful in an automobile vehicle such as radiator cooling motor and air-conditioning evaporator, comprises depositing a layer of brazing flow on an external and an internal side of a flat tube (10) section during a formation of the tube and after assembling of a heat exchanger. The flat tube is brazed with spacers (20), which are disposed in an exterior and an interior of the tubes. The deposition step is carried out in a form of a continuous or discontinuous row, and is carried out using a syringe, a dosing valve, an engraved roller, a paintbrush and by micropulverization and serigraphy. An average density of the flow on the heat exchanger surface of the tube is 0.5-8 g/m 2>. An independent claim is included for a heat exchanger. Selon l'invention, ledit procédé comprend une opération consistant à déposer une couche (40) de flux de brasage sur un côté d'une tranche (11) desdits tubes plats (10).Application aux systèmes d'échange de chaleur dans les véhicules automobile.