Steelmaking and continuous casting production scheduling is a multi-equipment assignment, multi-objective, multi-constraint, discrete and continuous variables hybrid optimization problem. Traditional modeling and solving meth-ods are usually adopted to solve it, but they cannot meet the requirement in terms of high scheduling accuracy and fast problem solving speed. A new two-stage optimal modeling algorithm is proposed in this paper. In stage one, we show that minimizing the waiting time from steelmaking to continuous casting is equivalent to maximizing the converter oper-ating time at first. Then we built a multiple-stage dynamic programming equation and optimization model using discrete variables, with the goal of maximizing the converter operating time. In stage two, we establish a linear programming conflict elimination model using continuous variables by converting a non-linear performance index into two equavalent linear optimization indexes including lead time, lag time between pratical casting and planned casting, and combining the other two indexes including time gap between furnaces on same caster and waiting duration for steel ladle among converters, refining furnaces and casters. On-site industry application validates that the proposed method can solve the scheduling problem with high speed and accuracy.%以某钢厂多台转炉及多台精炼炉对多台连铸机的复杂生产线为研究对象，针对其调度过程涉及多设备、多目标、多约束等调度要素，且离散和连续变量混杂，采用常规建模方法难以满足现场对调度的精度及排产速度的需求问题，提出一种新型的两阶段优化建模方法。首先，证明了炉次从炼钢到连铸总等待时间最小的调度目标与该炉次在转炉开始作业时间最大是等价的事实，并以离散型的设备变量为决策变量，以转炉开始作业时间最大为动态规划最优指标，建立设备指派多阶段动态规划基本方程和设备指派优化模型；然后，以炉次在设备开始作业时间的连续型变量为决策变量，并将准时开浇的非线性调度指标转化成与之等价的线性优化目标，以在同一台连铸机上浇铸的炉次之间断浇的时间间隔最小、钢包在设备之间的冗余等待时间最小、提前与滞后理想开浇时间的时间间隔最小为目标，建立线性规划冲突解消模型。工业实验表明所提出两阶段优化建模方法在求解速度与求解精度均满足现场要求。
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