Abstract
Since little is known quantitatively about the effect of limestone on the viscosity of cupola furnace slags, the writer experienced this important problem. The viscosity of molten slag was measured with a viscometer based on rotating cylinder method. As any refractory material is attacked by molten slag, he used a rotating cylinder covered with platinum and a platinum crucible, and the temperature of the slag was measured with a Pt-Pt. Rh thermocorple steeping in it directly,
He melted iron in cupola furnaces adding limestone 0-10% of the former, and found that slags which were made using limestone 1% in 0.1 ton cupola and 4% in l ton cupola have the smallest viscosity and the lowest melting temperature. Cast iron made in this manner also shows the better chemical and machanical properties.
This is probably due to the reason why slags which have smaller viscosity and lower melting temperature cover well over the upper surface of glowing cokes protecting cast iron from its bad influence, and the chemical reaction between molten slag and iron easily performed.
