变接触支持辊辊形及辊形配置技术在宽带钢热连轧粗轧机组的应用

Application of Variable Contact Backup Roll Contour and Configuration Technology on Roughing Mills of a Hot Wide Strip Mill

首钢迁钢2 250 mm热连轧生产线在2006年底投产后1年多的时间里,带钢的板形控制精度较低,需要进一步提高。粗轧后中间坯存在镰刀弯、负凸度和楔形大的板形问题,导致精轧控制稳定性差,造成板形控制精度较低。为了解决粗轧中间坯板形的问题,在粗轧R2机架上设计并应用了6次多项式变接触支持辊辊形和负凸度工作辊辊形,取代了原来采用的平辊形。此支持辊辊形可以使辊间接触长度随所轧制带钢宽度变化,消除了有害接触区,使得辊间接触应力均匀化,并提高了辊缝横向刚度,改善了轧辊的磨损辊形,并提高了板形调控能力。工作辊负辊形弥补了工作辊的热凸度,增强了板坯轧制过程的对中和稳定性。此支持辊辊形与工作辊辊形配置使用,大幅改善了中间坯的凸度、楔形和镰刀弯等板形质量,使得热轧产品的板形质量有10%左右的提高。

Within more than one year time after 2 250 mm Hot Strip Mill of Qian′an Iron and Steel Company of Shougang Steel Corporation was commissioned in the end of 2006,strip shape control precision was relatively lower.One of the factors resulting to that problem is that the transfer bar usually had bad profile and large camber after its rough rolling.And that kind of transfer bar will result strip shape defects of buckles,camber,wedge and tower coils after rolling work of finishing mill.For enhancing the control precision of strip shape,roll contour design and optimization works have been done.One kind of variable contact backup roll contour curve（VCR） with a six order of polynomials and negative crown contour were designed and applied respectively on back-up roll and work roll of roughing mill stand R1 and R2 instead of conventional flat backup roll.After the new backup roll contour technology and roll shape configuration mentioned above was applied on roughing mill,large improvement on crown,wedge and camber quality of transfer bar is obtained,and strip shape quality of hot rolled product is raised by 10 percent.