现代化挤压设备都采用型材牵引装置,使制品保持平直不扭曲,而且使以后的工序,如拉伸和中断锯切等也能实现自动化.最近几年,多孔模的挤压已实现了用一个联合动作的夹钳抓住所有制品,并用相同的速度牵引出相同的长度.根据这种作用原理,牵引装置已不再仅是一种输送装置;它实际上起到了变形设备的作用,它使流动较慢的制品强制性地在同一时间内达到流动最快制品相同的长度. Modern extrusion equipment uses profiled hitch devices to keep the product straight and untroubled and also to automate subsequent processes such as stretching and interruption of sawing etc. In recent years the extrusion of porous molds has been achieved with A co-operating grip grips all the product and draws the same length with the same speed. According to this principle of action the pulling device is no longer just a delivery device; it actually acts as a deforming device which Slowly moving products forcedly reach the same length as the fastest moving product at the same time.