连续薄带钢热浸镀锌线冷却塔区段带钢抖动原因分析

Cause Analysis of Strip Steel Jitter in Cooling Tower Section of Thin Strip Steel Continuous Galvanizing Line

某镀锌线的冷却塔上行段的带钢运行时存在大幅抖动和扭动问题,不仅影响连续热镀锌线镀层控制精度,而且对锌锭消耗成本有较大的负贡献。通过对锌锅区的沉没辊设备、带钢在停机和运行状态下进行了多项振动测试。并且利用轴向运动薄板的横向振动理论,分析了冷却塔上行段带钢大幅抖动的主要机理是:(1)锌锅内辊的晃动引起的带钢支承运动强迫振动共振;(2)冷却塔局部结构共振放大了张力波动,进而引发带钢参数激励共振。在了解机组动态特性和运行、操作规律的基础上,尝试建立了抑制带钢抖动的工艺参数调节理论。

A galvanizing line has a significant shaking and twisting problem during strip operation in the upstream section of the cooling tower,which not only affects the plat⁃ing control accuracy of the continuous hot-dip galvanizing line,but also contributes negative⁃ly to the cost of zinc ingot consumption.A number of vibration tests were conducted on the sinking roller equipment and strip steel in the zinc pot area under shutdown and operating conditions,and the theory of transverse vibration of axially-moving thin plates was used as well to analyze the main mechanism of the large shaking of the strip steel in the upstream section of the cooling tower,which were:(1)the vibration resonance was forced by the strip support movement caused by the shaking of the rollers inside the zinc pot;(2)the local structural resonance of the cooling tower amplifies the tension fluctuation,which triggers the excitation resonance of the strip parameters.On the basis of understanding the dynamic char⁃acteristics of the unit and the operation rules,an attempt was made to establish the theory of process parameter regulation to suppress strip jitter.