线材厂精轧机前活套是保证线材头尾公差质量的重要工艺措施。为此，介绍一种在线材精轧机前中轧机出口设置活套装置的方法；详述了活套装置的结构、动作原理以及活套闭环控制原理；给出了现场运行效果。 Wire mill finishing mill before the looper is to ensure that the quality of wire head and tail of the important process measures. To this end, a method of setting a looper device at the exit of a front mill of a wire rod finishing mill is introduced. The structure of the looper device, the principle of operation and the control principle of the looper loop are described in detail. The effect of on-site operation is also given.