采用质谱分析仪对转炉炉气进行在线检测分析，并采用炉气分析模型进行拟合及与实测结果进行比较，通过分析炉气中CO和CO2的变化规律，结果表明：应用指数模型能够较好的预报终点碳含量；三次方模型能够更好的反应转炉冶炼后期熔池中碳含量。

The off-gas of BOF is measured by mass spectrograph on-line and the refining process and end-point on time with the off-gas analysis is forecasted. The results show that the index model is applicable for forecasting carbon content of smelting end point; the cubic model is applicable for reflecting carbon content in molten pool during smelting anaphase.