冷轧钢卷挫、划伤缺陷产生机理及其治理技术

Mechanism analysis and treatment techniques for contusion and scratch defects of cold rolled coil

针对冷轧钢卷卷取后带钢表面出现挫、划伤缺陷的问题,对缺陷宏观与微观形貌进行了分析,研究了冷轧钢卷卷取后带钢表面的挫、划伤缺陷的形成机理,即带钢在卷取过程中沿卷筒周向的静态卷取张力不能与动态的摩擦力相平衡而造成带钢层与层之间的打滑碰撞,导致带钢表面出现挫伤和划伤缺陷。为此,从卷取张力、速度波动的抑制,张力制度的优化,设备的维护,运输装备的改造等方面提出了相应措施,并将其应用到某2030mm五机架冷连轧机组,挫、划伤缺陷的发生率从1.2%下降到0.1%,保证了产品质量,取得了较大的经济效益。

Aiming at the problems of contusion and scratch defects on the surface of the cold rolled strip after coiling,the macromorphology and micro-morphology of the defects were analyzed,and the mechanisms of defects were studied,i.e.the static coiling tension along the circumference of the reel during the coiling process cannot be balanced with the dynamic friction force,resulting in the slipping and collision between the strip layers,which causes the surface of the strip to be bruised and formed the defects.Therefore,the corresponding measures were proposed from the aspects of suppressing coiling tension and speed fluctuation,optimizing tension system,maintaining equipment,and reforming transportation equipment,etc.,and apply them to a 2030mm fivestand tandem cold rolling mill.The incidence of contusion and scratch defects was reduced from 1.2%to 0.1%,the products quality was assured and the greater economic benefits was achieved.