The entrainment of slag in the mold of a continuous caster is one of the most common sources of surface and internal defects in continuously cast steel. Unfortunately, very little is understood concerning this problem. Very little work has been done to examine the effect of physical properties, geometrical factors, or operational practices on the entrainment phenomenon.; The goal of this work is to provide an understanding of the entrainment phenomenon. An explanation of the mechanism of entrainment in the mold of a continuous caster will be given. This work focuses on the determination of the operational parameters necessary to continuously cast steel without slag entrainment occurring.; Entrainment studies were conducted using water models. Silicon oil and water were used to model slag and steel respectively. Experiments were conducted in a vortexing tank, a laboratory entrainment model, a model of a billet caster, a model of a bloom caster, and a model of a slab caster.; A laser technique for the measurement of two dimensional fluid velocities was developed. The critical velocity necessary to cause entrainment was measured to be 11.6 cm/s for a silicon oil and water system. Similitude was applied to the critical velocity necessary to entrain to produce a critical velocity necessary to entrain in a slag and steel system of 45.9 cm/s.; Experiments were conducted to determine the influence of density, viscosity, and interfacial tension on the entrainment phenomenon. From this data an equation was derived to predict the critical velocity necessary to cause entrainment in immiscible fluids. This equation is validated through its comparison to the work of others.; Curves were determined to show the relationship between the physical properties of the fluids, the geometrical factors of the models, and the operational procedures used during casting. Parameters such as casting speed, submersion depth, submerged entry nozzle design, argon purging, mold level control, clogging, and slag foaming are related to each other and explained.; It is hoped that this work will produce results that when coupled with the existing mathematical models can be used to set up and operate a continuous caster more efficiently.
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机译：连铸机结晶器内夹渣是连铸钢表面和内部缺陷的最常见来源之一。不幸的是，关于这个问题了解得很少。在检查物理性质，几何因素或操作实践对夹带现象的影响方面所做的工作很少。这项工作的目的是提供对夹带现象的理解。对连铸机的结晶器中的夹带机理进行说明。这项工作的重点是确定连续铸造钢而不会夹渣的必要操作参数。引诱研究是使用水模型进行的。硅油和水分别用于模拟炉渣和钢。实验是在涡流罐，实验室夹带模型，钢坯连铸机模型，大方坯连铸机模型和板坯连铸机模型中进行的。开发了用于测量二维流体速度的激光技术。对于硅油和水系统，导致夹带所需的临界速度经测量为11.6 cm / s。对夹带所必需的临界速度应用了相似性，以产生夹带在钢渣和钢系统中所必需的临界速度，该临界速度为45.9 cm / s。进行实验以确定密度，粘度和界面张力对夹带现象的影响。从该数据推导出方程式，以预测引起混溶流体夹带所需的临界速度。该等式通过与他人的比较得到验证。确定曲线以显示流体的物理特性，模型的几何因素以及浇铸过程中使用的操作程序之间的关系。浇铸速度，浸入深度，浸入式喷嘴设计，氩气吹扫，结晶器液位控制，堵塞和炉渣起泡等参数相互关联并进行了说明。希望这项工作能够产生与现有的数学模型结合使用时可以更有效地设置和操作连铸机的结果。
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