Molten Metal for Ductile Iron from the Cupola Furnace.

Among cupola furnaces, hot blast cupolas with acid linings represent the most favorable prerequisites for the manufacture of the base metal for ductile cast iron. The melt has a high temperature which cannot be achieved with cold blast cupolas. Hot blast cupolas are used to good advantage for melting capacities in excess of 10 t/hr. However, because the molten metal has an elevated sulfur content, desulfurization outside the cupola is necessary.