Triple furnace for brazing aluminium parts incorporating cavities in a salt bath with argon gas

摘要

Triple furnace for brazing aluminium parts incorporating cavities in a salt bath with argon gas where by means of a vertically adjusted device located within them the parts which are to be brazed are heated only therein and then brazed thus avoiding the use of two furnaces and in which in order to obtain repeated and rapid lighting and relighting of the furnace the latter is provided with three sources of heat as a triple furnace in which the salt is contained in a vessel of refractory material which is able to hold it and then passed to a second highly thermally insulated vessel with an electric resistance located between the two vessels which heats the salt in order to cause it to melt and where in order to obtain all this in a short time a parabolic heater of great power is fixed to the vertically adjustable device above the salt and then removed once the furnace has started, and finally some nickel electrodes immersed in the salt through which current passes. In addition to this, in order to keep the parts which are to be brazed together, weights which are also provided with levers in order to achieve large forces with small masses are used instead of expensive welding points in order to prevent the salt from entering into combination with the sheets at the junction points, appreciably reducing their mechanical strength. In addition to this when brazing parts provided with cavities, instead of causing the salt to circulate within them an inactive gas which has been preheated in a coil is caused to circulate. IMAGE