METHOD AND APPARATUS FOR PRODUCING SPHEROIDAL GRAPHITE CAST IRON

PURPOSE:To raise the spheroidal graphite ratio and improve the mechanical property of a spheroidal graphite cast iron by adding an alloy of pure Mg and rare earth element into molten cast iron containing the elements used as molten spheroidal graphite cast iron in a specific atmospheric pressure and then, casting into a mold after adding and stirring an alloy for inoculation of Fe-Si alloy, etc. CONSTITUTION:A ladle 5 incorporating the molten iron 4 is carried to just above a vessel 1 through a monorail, etc. Then, the ladle 5 is descended with a hoist, etc., and laid and incorporated into the vessel 1. A desired adding agent is filled into a filling box 14 in a holder 15, and by swinging and descending a cover 7, the vessel 1 is closed. By using a clutch clamping device 8, the vessel 1 and the cover 7 are sealed. The inner part in the vessel 1 is made to be the pressurized condition to 3-7atm. with the air fed from gas feeding pipe 9. Then, by working a pressure-in cylinder 13, the filling box 14 is descended through a holder 15 and the filling box 14 is dipped into the molten metal 4. After completing the adding treatment to the alloy for inculation, the air is discharged through a gas exhaust pipe 10, and fume and dust are collected with a dust collector.