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提高热送连铸坯温度的试验研究 总被引:1,自引:1,他引:0
采用远红外非接触测温和射钉法对武钢三炼钢的板坯连铸机典型二冷模式下铸坯的表面温度及凝固坯壳厚度进行了研究,发现通过矫直区进入水平段之后铸坯表面温度持续降低,机尾附近铸坯表面温度仅为710~820℃。根据坯壳厚度变化得出的典型二冷模式下综合凝固系数K为24~27mm/min^1/2,根据凝固终点与K的关系,将浇铸低碳铝镇静钢时的拉速由1.1m/min左右提高到1.4~1.5m/min,使铸坯的凝固终点向机尾延伸,铸坯出机表面温度提高到了920~940℃。 相似文献
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在坯龄模型基础上,根据计算出的铸坯表面温度与目标温度的差值进行优化调节水量。设计了宣钢150t1#方坯连铸机二冷动态配水模型,实现了铸坯表面温度自适应控制。该模型使二次冷却更加均匀,减少了铸坯表面回温,以便达到控制铸坯组织和内部质量的目的。 相似文献
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应用二冷区铸坯表面温度测定和连铸坯硫印、低倍检验等方法,分析评价了攀钢板坯连铸现行二冷制度对铸坯内部质量的影响,并在此基础上优化完善了连铸二冷配水制度。结果表明,采用增大二次冷却强度、增加二冷段后区铸坯冷却能力的配水制度对减轻铸坯中心偏析、扩大铸坯等轴晶率、提高铸坯内部质量有明显效果,为进一步完善连铸二冷控制制度提供了坚实的技术基础。 相似文献
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采用远红外非接触测温和射钉法对武钢三炼钢的板坯连铸机典型二冷模式下铸坯的表面温度及凝固坯壳厚度进行了研究,发现通过矫直区进入水平段之后铸坯表面温度持续降低,机尾附近铸坯表面温度仅为710~820℃.根据坯壳厚度变化得出的典型二冷模式下综合凝固系数K在24~27mm/min1/2之间,根据凝固终点与K的关系,将浇铸低碳铝镇静钢时的拉速由1.1m/min左右提高到1.4~1.5m/min,使铸坯的凝固终点向机尾延伸,铸坯出机表面温度提高到了920~940℃. 相似文献
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In this paper, a compensation control model of secondary cooling process of billet continuous casting for quality steel has been presented. The effects on the spray control of the various parameters such as steel superheat, casting speed, cooling water temperature and chemical component of steel were considered. The parameters of control model were determined to associate with the two‐dimensional heat transfer equation and solved by finite‐difference method. Effects of steel superheat and cooling water temperature on surface temperature, solidification structure and solidifying end point were discussed. Results indicate that steel superheat significantly affects solidification structure and solidifying end point but has a little effect on slab surface temperature. Moreover, secondary cooling water temperature affects surface temperature and solidifying end point but has a little effect on solidification structure. The surface temperature and solidifying end point can be maintain stabilized through applying the compensation control model when steel superheat and cooling water temperature vary. The models have been validated by industrial measurements. The results show that the simulations are in very good agreement with the real casting situation. 相似文献
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Real-time simulation of heat transfer in continuous casting 总被引:10,自引:0,他引:10
Seppo Louhenkilpi Erkki Laitinen Risto Nieminen 《Metallurgical and Materials Transactions B》1993,24(4):685-693
A real-time heat-transfer model for continuous slab casting is presented. The model calculates the strand temperatures and
the solid shell thickness profile along the machine as a function of the actual casting variables, strand geometry, and steel
grade. The special requirements con-cerning the real-time use of the model and, in general, the accuracy of the model are
also studied and discussed. The model has been tested by carrying out industrial trials. Some examples of the differences
between the calculated and measured surface temperatures are presented. A spe-cial procedure to determine the boundary conditions
for the secondary cooling zones from tem-perature measurements is also described. 相似文献
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Zhichao Dou Qing Liu Bao Wang Xiaofeng Zhang Jianfeng Zhang Zhigang Hu 《国际钢铁研究》2011,82(10):1220-1227
Secondary cooling control is an important factor in the continuous steel casting process. This paper reviews popular control models and analyzes their principles and characteristics. On the basis of the review, this paper proposes a new concept called “effective‐superheat” and a new control model called “synthetical model dynamic control method based on online temperature measurement.” The model, which combines the advantages of the popular models reviewed, not only allows steady, accurate and dynamic control of slab surface temperature, but also provides the temperature profile and the end of the liquid pool. In addition, this paper also discusses the current problems with secondary cooling control and the related development trends, which may be helpful for further development of secondary cooling control technology and informationization of the continuous casting process. 相似文献
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钢液连铸二次冷却的效果直接影响连铸坯质量,为了合理地控制二次冷却过程,多种静态和动态控制工艺模型被提出。系统综述了目前二冷静态和动态控制工艺模型的发展,包括二冷区各回路水量与拉速呈一次线性或二次曲线关系的二冷控制工艺模型、基于修正有效拉速的二冷动态控制工艺模型和基于在线传热计算的二冷动态控制工艺模型等,以及基于钢液过热度和二冷进水温度的二冷控制先进工艺模型和基于在线温度测量反馈调节各回路水量的二冷动态控制工艺模型。随着二冷控制工艺模型的发展,其控制的实时性、可靠性、准确性以及运行的稳定性也逐渐提高,从而为高质量铸坯生产及智能化二冷控制奠定了基础。 相似文献
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A transient simulation and dynamic spray cooling control model for continuous steel casting 总被引:6,自引:0,他引:6
Richard A. Hardin Kai Liu Christoph Beckermann Atul Kapoor 《Metallurgical and Materials Transactions B》2003,34(3):297-306
A two-dimensional heat-transfer model for transient simulation and control of a continuous steel slab caster is presented.
Slab temperature and solidification are computed by the model as a function of time-varying casting speed, secondary spray
cooling water flow rates and temperature, slab thickness, steel chemistry, and pouring and ambient temperatures. Typically,
the solidification path, temperature-solid fraction relationship, is prescribed. However, if these data are not available,
a microsegregation solidification model that approximates the effects of steel chemistry and cooling rate is incorporated
in the caster model. Measured slab surface temperatures recorded from an operating caster are compared with predictions from
the transient model. These demonstrate that the model typically can predict the temperature response at the slab surface within
30 °C. Results of several simulations are given to demonstrate the effects of changing casting conditions on the slab thermal
profile, end of liquid pool, and solidification end point. A control methodology and algorithm suitable for online control
of a continuous casting machine is described, and the ability to control the surface temperature profile by dynamically adjusting
secondary spray cooling flow rates is demonstrated by simulation. Results from a preliminary version of the model that is
capable of running in real time are presented and are compared with the slower, but more realistic, version of the model. 相似文献
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根据奥氏体不锈钢的热物理参数和二冷区各区出口目标温度,建立了不锈钢220mm×220 mm铸坯动态二冷综合控制模型和末端拉速电磁搅拌-拉速优化模型。304奥氏体不锈钢连铸生产应用结果表明,在该钢正常工作拉速0.8~1.1 m/min,根据目标温度(足辊1080℃,一区1 070℃,二区1060℃,三区1045℃,进拉矫机980℃)制定相应比水量(0.30~0.33 L/kg),模型实时计算表面温度与目标温度对比,进行在线控制,铸坯温度均匀、稳定,冶金质量良好。 相似文献
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针对连铸生产过程中的二冷配水问题,建立了铸坯的凝固传热数学模型。通过实时模拟计算铸坯的温度场,并与PID控制技术相结合,开发了在线二冷控制模型。模型能自动根据钢种、铸坯规格及工艺参数的变化动态调整二冷控制水量,将铸坯的表面温度控制在工艺目标值附近。通过设计合理的控制系统架构,确保了二冷控制系统的稳定性及可靠性。在线测温结果表明,模型具有很高的计算精度。当拉速、浇注钢水过热度变化时,模型能快速将水量调整到目标值,速度快且超调小,从而确保铸坯的表面温度跟踪误差始终限制在较小范围内;当浇注过程处于相对稳态时,铸坯的表面温度保持在目标值。目前,模型已经应用于宝钢内外的多台连铸机,应用效果良好。 相似文献