共查询到19条相似文献,搜索用时 994 毫秒
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异型坯连铸二冷区配水模型研究 总被引:1,自引:0,他引:1
根据异型坯连铸机的特点,建立了碳素结构钢工字坯连铸过程凝固数学模型,分析了工艺参数地结晶器和二冷区铸坯凝固的影响;确立了碳素结构钢二冷区最佳冷却冶金准则。经过大量计算,总结出基于目标温度曲线和液芯长度控制的二冷区配水模型。 相似文献
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建立连铸坯凝固传热数学模型,利用现场实测数据对所建模型进行了验证,并对影响铸坯温度和坯壳厚度的拉坯速度、浇注温度、二冷区水量等因素进行了分析。结果表明:模型的计算精度满足实际生产的需要,影响因素中,拉坯速度和二冷区水量对铸坯温度和坯壳厚度的影响最大。因此调节拉速,改善二冷区制度是铸坯生产工艺中的重要操作。 相似文献
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提出了一种基于带有变异算子的改进粒子群算法对二冷区水量进行优化的新方法。首先应用凝固原理和时空有限体积法建立连铸板坯凝固传热的数学模型,数值模拟结果与现场实测结果相符。再利用改进粒子群优化算法对二冷区各段的水量进行优化,优化之后的二冷制度使铸坯各段表面温度冷却速率和温度回升速率趋于平缓,与冶金准则对改善铸坯冷却过程和提高产品质量的要求相吻合。 相似文献
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Numerical Simulation of the Thermo-Mechanical Process for Beam Blank Continuous Casting 总被引:1,自引:0,他引:1
W. Chen Y.Z. Zhang C.J. Zhang L.G. Zhu B.X. Wang W.G. Lu J.H. Ma 《金属学报(英文版)》2007,20(4):241-250
The aim of this study was to simulate the solidification process of beam blank continuous casting, and then find the reasons for the typical defects of the beam blank. A two-dimensional transient coupled finite element model has been developed to compute the temperature and stress profile in beam blank continuous casting. The enthalpy method was used in the heat conduction equation. The thermo-mechanical property in the mushy zone was taken into consideration in this calculation. It is shown that at the mold exit the thickness of the shell had its maximum value at the flange tip and its minimum value at the fillet. The temperature had a great fluctuation on the surface of the beam blank in the secondary cooling zone. At the unbending point, the surface temperature of the web was in the brittleness temperature range under the present condition. To ensure the quality, it is necessary to weaken the intensity of secondary cooling. At the mold exit the equivalent stress and strain have higher values at the flange tip and at the web. From the spray 1 to the unbending point, the maximum values of stress and strain gradually moved to the internal section of the flange tip and the web. However, whenever, there were bigger stress and strain values near the flange tip and the web than in the other parts, it must be very easy to generate cracks at those positions. Now, online verification of this simulation has been developed, which has proved to be very useful and efficient to instruct the practical production of beam blank continuous casting. 相似文献
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基于Matlab数值计算,对板坯连铸凝固传热问题进行研究,得到随板坯厚度及其与结晶器弯月面距离变化的板坯温度场分布,通过拟合得到板坯凝固点末端位置与二冷总供水流量、过热温度和拉坯速度的关系式,分析二冷区水量分配比对结晶器和二冷区内单位长度板坯热损失率和板坯表面温度梯度的影响。结果表明:板坯温度随冷却阶段的不同其温度变化趋势显著不同;随着过热温度和拉坯速度的增大、二冷总供水流量的减小,板坯凝固点末端位置增大;拉坯速度对板坯凝固点末端位置的影响最为显著,其次是二冷总供水流量,过热温度对其影响较小。通过适当调整二冷区内水量分配比可实现降低板坯表面温度梯度和较少热损失率的折衷,从而在提高板坯质量的同时也提高其蓄能,以实现板坯连铸过程的节能。所得结果能对板坯连铸凝固过程的参数设计和动态运行提供依据和理论指导。 相似文献
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金刚石压机缸梁的铸造 总被引:1,自引:0,他引:1
针对金刚石压机缸梁铸件的结构特点 ,对不同铸造工艺方案进行了对比分析。采取下部引气、局部强制冷却、分层浇注等工艺方法 ,实现了铸件顺序凝固与补缩要求 ,铸件一次浇注成功 相似文献