一种液驱冷轧机辊热凸度动态SVR预测模型

辊热凸度是当轧件发生变形或因摩擦作用生成热量而引起轧辊温度上升并由此产生轧辊外形尺寸改变的现象。为了降低液驱冷带轧机辊随温度的变化影响,综合分析了辊热凸度因素引起的变形效果差异性。选择液驱轧机作为测试对象,从热凸度作用原理方面考虑,同时根据实际获得的监测参数探讨了辊热凸度情况受到外部因素的影响程度。建立基于支持向量机的液驱冷带轧机辊热凸度动态预测模型,该模型结构较简单,并且可以获得优异的性能。对于辊热凸度的预测表现出了明显的优势。利用SVR模型以及交叉验证的方式确定参数,结果形成了一致的变化趋势与周期性特征。拟合优度与均方根误差分别为0.84与0.0153,获得了较理想的预测性能。该研究对提高板材的控制精度以及轧机节能具有较好的实际指导意义。

Application of the Plate Crown Prediction

The program of the plate crown optimal prediction applied in the plate mill of Wuhan Iron and Steel(Group) Co. Ltd. is described. Optimal prediction is programmed in ALPHA 4000. The original profile, wear, expansion and deformation of work rolls are introduced into the program. The plate crown is controlled by the original profile of work rolls and the draft whose objective is the optimal plate crown. The run schedule is also optimized through the optimal prediction of the plate crown.

Numerical simulation and model of control-efficiency of thermal crown of work rolls in cold rolling

Aiming at accuracy control of the thermal crown of work rolls in cold rolling,new parameters such as regulation domain and control-efficiency factors were proposed and a numerical analysis model of the thermal crown of work rolls was established using finite difference method to study roll's thermal deformation.Based on simulation results,the influences of control-efficiency factors on thermal crown are presented and the thermal crown of work rolls is analyzed after taking sub-cooling of sprinkling beam into consideration.It has been found that the control-efficiency factor of any position on the roll's surface is linear function of the temperature and the control ability of water temperature is stronger than other control parameters.In addition,the verification of the model has been carried out based on the producing technology data in some factories and the numerical simulation results coincide well with the experimental data.Therefore,this work has important value for on-line control of roll's crown in cold rolling.

极薄规格冷轧带钢板形控制研究

针对厚度0.2 mm以下极薄规格带钢在生产过程中经常出现中浪缺陷的问题,对某UCM轧机极薄规格带钢局部中浪板形缺陷与轧制过程数据进行了分析,通过工作辊温度测量与工作辊热凸度引起平坦度的有限元计算,表明中浪缺陷是由于轧辊热凸度过大而造成的。分析了轧辊热凸度影响因素,以及UCM轧机轧辊辊型,板形目标曲线,中间辊轴向横移,乳化液,中间辊、工作辊弯辊力等参数对极薄规格带钢板形的影响。结果表明:通过板形目标曲线优化设计,合理配置中间辊轴向横移量、工作辊弯辊、中间辊弯辊3种板形调节手段,增加中间辊轴向横移量,增加工作辊弯辊、中间辊弯辊负弯的调节余量,可在消除中浪的同时避免边浪的产生。同时,通过优化工艺润滑制度,降低乳化液温度到合理范围,可有效提高分段冷却的板形控制能力,使带钢平坦度回归到板形目标曲线设计范围,释放弯辊调控量。再有,通过支撑辊边部辊型优化设计,可提高辊型对边浪的抑制能力,在减少中浪的同时不产生边浪。采用上述措施,将中浪缺陷减小到5 IU以内,极薄规格带钢中浪板形缺陷问题得到了有效解决。