热轧高强度薄规格酸洗板轧制稳定性研究

RESEARCH ON ROLLING STABILITY OF HOT ROLLED HIGH STRENGTH THIN PICKLED PLATE

因成分复杂、强度高、规格薄等特点,热轧高强度薄规格酸洗板在轧制过程中稳定性差,易发生头部轧破、带钢跑偏、尾部甩尾等现象,进而导致带钢表面出现明显的辊印降级,甚至发生堆钢事故,造成经济损失。为保证稳定性,通常会采取提高出钢温度的方法,但会导致表面氧化铁皮缺陷降级率升高。基于此,对头尾控制程序进行了优化,将精轧除鳞头部特殊控制,在双排模式下带钢头部采用单排除鳞,在F1咬钢后开启双排模式,提高头部穿带过程的稳定性;开发了F7机架尾部AGC二次大抬起功能,在F6抛钢后F7 AGC以4.6 mm/s速度抬起,降低尾部轧制力,且尾部厚超60μm的距离控制在8 m以内;研究了F1和F2机架间水除鳞时序,将F1-F2机架间水逐步投用,让出带头带尾部分,机架间水的使用将精轧轧制速度提高1~3 m/s,减少尾部温降,提高尾部的轧制稳定性;轧制油投用降低负荷5%;优化轧机负荷分配,F2压下率<50%,明显改善了轧辊剥落现象,辊系氧化铁皮的发生率由0.28%降至0.25%。通过优化生产过程各段参数,提升了热轧高强度薄规格酸洗板的轧制稳定性和表面质量。

Due to its complex composition,high strength,and thin specifications,hot-rolled high-strength thin pickled plates have poor stability during the rolling process,and are prone to phenomena such as head breakage,strip deviation,and tail shaking,which can lead to significant roll mark degradation on the surface of the strip and even steel stacking accidents,resulting in economic losses.To ensure stability,the method of increasing the tapping temperature is usually adopted,but it may lead to an increase in the degradation rate of surface oxide scale defects.Based on this,the head and tail control program was optimized,with special control of the precision rolling descaling head.In the double row mode,a single descaling was used for the strip head,and after F1 biting the steel,the double row mode was activated to improve the stability of the head threading process.It has developed the F7 rack tail AGC secondary lifting function,which lifts the F7 AGC at a speed of 4.6 mm/s after F6 steel throwing,reducing the tail rolling force,and controlling the distance of the tail thickness exceeding 60μm within 8 m.The timing sequence of water descaling between F1 and F2 stands was studied.The water between F1~F2 stands was gradually put into use,giving way to the leading and trailing parts.The use of water between stands increased the precision rolling speed by 1~3 m/s,reduced the temperature drop at the tail,and improved the rolling stability at the tail.Reduce the load by 5%when using rolling oil.Optimizing the load distribution of the rolling mill,the F2 reduction rate is less than 50%,significantly improving the phenomenon of roll peeling,and reducing the incidence of iron oxide scale in the roll system from 0.28%to 0.25%.By optimizing the parameters of each section of the production process,the rolling stability and surface quality of hot-rolled high-strength thin specification pickled plates have been improved.