早在七十年代初期,我们就在φ76试验机组上研究了张力、单架的减径量及其分配、孔型设计等对张减钢管内六方的影响。通过近十年的反复试验和实践,我们已基本上弄清了影响内六方的因素,也成功地找到了一些克服内六方的方法。现将我们在有关内六方问题上作试验所取得的初步成果总结如下: As far back as the early 1970s, we have studied the effects of tension, the reduction of single frame and its distribution, hole design on the hexagonal reduction of steel pipe in the φ76 test unit. After nearly a decade of trial and error, we have basically identified the factors that affect the inner six parties and successfully found some ways to overcome the inner six parties. We have summarized the following preliminary results of our experiments on the question of the six parties: