热连轧机组轧辊温度场及热辊型

Research on roll temperature field and hot roll crown of hot continuous rolling mills

针对热连轧机组轧辊温度场无法精准预测引起的辊耗及板形问题。为了实现轧辊温度场与热辊型的精确预报来减少异常辊耗和避免重大生产事故的发生,运用数值解析的有限差分法和轧辊热传导方程建立了适合于热轧轧辊温度场与热辊型模型,在此模型基础上引入热轧机组的轧辊冷却水智能分段冷却控制系统,充分考虑复杂状态下冷却水的存在和冷却水流速对轧辊温度场与热辊型的直接影响。结合热连轧轧制过程中的设备参数及其工艺特点,同时考虑轧制钢卷数量递增对轧辊温度场和热辊型的循环叠加作用,编写程序将理论计算公式、模拟调控模型与现场实际工艺设备参数相结合作为分析的研究对象。首先通过现场轧辊测温设备对工作辊和支撑辊进行温度测量,并将测得的实际温度分布值与模型计算值进行对比分析,得到相近的轧辊温度和轧辊凸度变化趋势以及一致的温度和凸度数值,验证了模型计算的准确性和有效性。随后根据结果进行研究分析,得到了钢卷数量变化对轧辊温度和辊凸度的影响,发现了钢卷数增加对温升的叠加影响,同时发现10卷左右将会完成轧辊温度场的温升稳定,同时分析得出冷却水流速在3种不同速度下的轧辊温度沿辊身方向分布情况。最终实现了对工作辊和支撑辊温度场与热辊型的精确预报,并且为后续利用轧辊温度场与热辊型模型进一步调控轧辊辊温分布奠定模型基础。

Aiming at the problems of roll consumption and shape caused by the inability to accurately predict the roll temperature field of a hot continuous mill.In order to realize the accurate measurement of the temperature field of the roll and the shape of the hot roll,reduce the abnormal consumption of the roll and avoid the occurrence of major production accidents,a numerical finite difference method and roll heat conduction equation were used to establish a model suitable for the roll temperature field and hot roll profile of a hot rolling mill.Based on this model,the roll cooling water intelligent segmental cooling control system of the hot rolling mill is introduced above,fully considering the existence of the specific parameters of the cooling water in the complex state of the cooling water and the direct influence of the cooling water flow rate on the roll temperature field and the hot roll crown.Considering the equipment parameters and process characteristics in the rolling process of hot tandem rolling,and considering the cyclic superposition effect of the increasing number of rolled steel coils on the roll temperature field and hot roll profile,the program is written to combine the theoretical calculation formula,simulation control model and field practice.The combination of process equipment parameters is the research object of analysis.Firstly,the on-site roll temperature measurement equipment is used to measure the temperature of the work roll and the backup roll,and the measured actual temperature distribution value is compared with the calculated value of the model,and the similar roll temperature and roll crown change trend as well as the consistent temperature and crown are obtained.The degree value verifies the accuracy and validity of the model calculation.Subsequently,the influence of changes in the number of steel coils on the roll temperature and roll crown was obtained by means of research and analysis based on the results,found the superimposed effect of the increase in the number of steel coils on the temperature rise,and found that about 10 coils will complete the temperature rise of the roll temperature field,and at the same time analyzed the cooling water roll temperature distribution along the roll body direction at three different flow rates.Finally,the accurate prediction of the temperature field of the work roll and the backup roll and the shape of the hot roll is obtained,and it lays a model foundation for further regulating roll temperature distribution by using roll temperature field and hot roll model.