杭钢100t精炼钢包炉经过实施永久层整体浇注、耐火材料综合砌筑、造渣工艺调整等措施，包龄提高到61炉，增加了钢包运行的安全性。......

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In the process of VHD,argon is blown into the molten steel throuht the porous plugs which are mounted in the ladle botto......