Abstract: A brazing system for brazing component members of a workpiece has a brazing chamber an inside of which is made a heating space of a volume corresponding to the workpiece, a radiant heating means provided with a plurality of heating sources which are positioned so as to correspond to a plurality of regions into which two facing surfaces of the workpiece are respectively divided, a convection heating means for circulating a heated inert gas to the heating space so as to heat the workpiece, and a control means for controlling the operation of the heating sources and the circulation of the inert gas. Each heating source is independently controlled by the control means, and the convection heating means circulates the inert gas so as to reduce a temperature difference of the workpiece caused by the heating sources.

Abstract: In the production of aluminum ingots by the direct chill casting process, in which the conventional chilled mold is equipped with a thermally insulated "hot top," smooth surfaced ingots are produced under conditions obtained by correlating of the length of the chilled mold, the casting rate and the head of molten metal in the hot top. Preferably the values of chilled mold length and metalostatic head are selected so as to be tolerant of some variation of metalostatic head which is difficult to avoid in the simultaneous operation of a large number of molds under level pour conditions.