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用结晶器壁内表面光洁度的假设，提出了处理结晶器、铸件有间隙接触问题的方法，避免了测定铸件表面温度或结晶器热流密度这一难题，建立了铸拉时的温度场，得到了铸件的温度分布、液穴形状及结晶器与铸件间间隙值与工艺参数的关系。同时，提出了一种新的摩擦计算模型，并求得了摩擦应力与间隙值、表面光洁度和铸件表面剪切强度之间的关系。然后根据限制铸拉速度的主要缺陷，即凝固壳断裂和冷隔，通过计算铸件截面承受的摩擦力、热应力和液穴形状，得到了铸拉工艺的极限速度，计算值与实测值吻合。
Based on the assumption of the inner surface finish of the mold wall, the method of dealing with the problem of gap contact between the mold and the casting is proposed, which avoids the problem of determining the surface temperature of the casting or the heat flux of the mold. The temperature field during casting is established. The temperature distribution of the casting, the shape of the liquid hole and the relationship between the gap value between the mold and the casting and the process parameters. At the same time, a new model of friction calculation is proposed, and the relationship between the friction stress and the clearance value, the surface finish and the surface shear strength of the casting is obtained. Then according to the main limitation of casting speed, that is, solidified shell fracture and cold separation, the ultimate speed of casting process was obtained by calculating the frictional force, thermal stress and liquid hole shape of the cross section of casting. The calculated values agree with the measured values.