生产薄的镀锌板规格时如何防止冷折皱？

天物彩板专注彩板行业16年——生产薄的镀锌板厂家规格_天津薄彩钢板冷褶皱请拨打网站上方电话咨询

    带钢出炉后，温度下降，屈服强度提高。但退火后，带材的屈服强度远低于热轧态。此外，出口段的连续停启导致张力波动较大，因此在生产板出口段存在较多的冷皱。

      冷皱一般发生在以下三种情况：一是活套内速度提高时；二是矫直辊工作时带钢发生扭曲时；三是卷取机张力相对较高的区域。活套提速最容易产生冷折痕。很多人不知道的一件事是，在滚筒从低速到高速运行的过程中，虽然滚筒是旋转的，但存在着一个类似直线运动的加速度过程，包括轴加速度和加速度转矩。对于主动辊，扭矩来自电机，而被动辊的加速扭矩来自辊上带钢的张力或张力。也就是说，当出口停止后速度增加时，出口活套中的辊由静态或低速运行状态变为高速运行状态，由出口张力辊通过带钢驱动。

        活套中许多辊的扭矩来自出口张力辊和活套之间的张力。可见，数量多，容易造成高张力带钢的冷皱。为了防止单辊纠偏导致带钢镀后单侧张力产生滑移线现象，在出口处采用双辊纠偏，但会造成带钢不在同一平面上产生变形，也会使张力在带钢中流动扰乱，导致冷折痕的发生。为了防止镀锌板的塌陷，使用了大量的张力，但其效果是带材可能会起皱，这很容易理解。为了防止冷皱，首先要减缓出口卷取的提升速度。生产中存在一些矛盾，因为生产薄板时生产线速度很快，允许停、切、卸、收的时间比较短，所以操作人员急于提速。

         为防止产生废品，工艺段的主要作业必须适当降低生产线速度，配合作业。此外，如果卷取已经开始，快速和慢速加速节省的时间不会太多。其次，要注意矫正辊，防止带钢严重变形和起皱。可缩小纠偏辊的纠偏范围，甚至可根据板形将纠偏辊对中或固定在适当位置，稳定后恢复自动运行。薄板一般都是窄板，稍偏滚压冲击不太大。此外，只要卷取张力降低，就可以少涂机油或使用钢套和纸套来防止卷取机起皱。

After the strip is out of the furnace, the temperature drops and the yield strength increases. But after annealing, the yield strength of the strip is much lower than that of the hard rolling state. In addition, the continuous stop and start-up in the exit section lead to great tension fluctuation, so there are many cold wrinkles in the exit section of the production sheet. Cold wrinkling generally occurs in the following three situations: first, when the speed is increased in the looper; second, when the strip steel is twisted when the straightening roller is working; third, in the area where the tension is relatively high on the coiler. Looper raising speed is the most prone to cold crease. One thing that many people don't know is that in the process of roller running from low speed to high speed, although it is rotating, there is an acceleration process like linear motion, including shaft acceleration and acceleration torque. For the active roller, the torque comes from the motor, while the acceleration torque of the passive roller comes from the tension or tension of the strip steel on the roller. That is to say, when the speed is increased after the exit stops, the roller in the exit looper has a process from static or low-speed running state to high-speed running state, which is driven by the exit tension roller through the strip steel. The torque of many rollers in the looper comes from the tension between the exit tension roller and the looper. It can be seen that the number is large, so It is easy to make the cold wrinkling of the strip steel with high tension. In order to prevent the slip line phenomenon caused by the single side tension of the strip steel after plating due to the single roll deviation correction, the double roll deviation correction is used at the exit, but it will cause the strip steel not in the same plane and produce the distortion, and also make the tension flow in the strip steel disturbed, resulting in the occurrence of cold crease. In order to prevent the collapse of the galvanized sheet, a lot of tension is used, but the effect is that the strip may wrinkle, which is easy to understand. In order to prevent cold wrinkling, the first thing is to slow the lifting speed of the exit coiling. There are some contradictions with production, because the production line speed is very fast when producing thin plates, and the time allowed to stop, cut, unload and take up is relatively short, so the operators are eager to speed up. In order to prevent waste products, it is necessary for the main operation of the process section to properly reduce the speed of the production line and cooperate with the operation. Moreover, if the coiling has started, the time saved by fast and slow speed up will not be too much. Secondly, it is necessary to take care of the rectifying roll to prevent the serious distortion of strip steel and wrinkle. The rectifying range of the rectifying roll can be reduced, and even the rectifying roll can be aligned or fixed at a proper position according to the shape of the plate, and the automatic operation can be resumed after it is stable. Thin plates are generally narrow plates, slightly off the roll impact is not too big. In addition, as long as the take-up tension is reduced, the wrinkle of the coiler can be prevented by applying less oil or using steel sleeve and paper sleeve.