Yojukinzokunokyuyo * toshutsuhanpukunyoruyojukinzokuyokunokakuhanseigyohoho

摘要

PURPOSE:To inhibit the scattering of molten metal to outside of a vessel, by adjusting the maximum pressure during pressurizing after switching on the basis of pressure inside a tubular refractory material just before switching an evacuating mode to a pressurizing one and the maximum pressure in the preceding pressurizing mode. CONSTITUTION:In agitatively refining molten metal with the motion of sucking- up and vomitting in a refining vessel by immersing the lower end of a tubular refractory material into said molten metal and alternatively repeating evacuating and pressurizing, the optimum value of an amount of pressurizing gas to be supplied after switching is determined by calculation on the basis of pressure inside the tubular refractory material just before switching an evacuating step to a pressurizing one and the maximum value just before switching an evacuating step to a pressurizing one and the maximum value of the pressurizing gas supplied in the preceding pressurizing step, to adjust the maximum pressure during the pressurizing to a proper level. Thus, the scattering of the bath caused by the ejection of gas is inhibited, the maximum agitation energy can be applied, and the effective refining operation is safely and efficiently performed.