NEW HOT-TOP CONTINUOUS CASTING METHOD FEATURING APPLICATION OF AIR PRESSURE TO MOLD.

Air is sent through the narrow clearance between the refractory header box and the upper surface of the water-cooled metallic mold at a pressure that is approximately equivalent to the static pressure of the molten metal there. The ingots have a smooth surface and an extremely thin layer of inverse segregation. The important conditions include 1) proper mold length, 2) small and uniform clearance between header and mold, 3) uniform supply of lube oil and 4) proper coordination of withdrawal speed, air consumption and metal level. Also important are the properties such as liquidus-solidus range, viscosity, surface tension, thermal conductivity and contraction during solidification.