锥形方管无模拉伸断面形状变化的实验

Experiment Study on Section Shape Variations During Tapered Square Pipe Dieless Drawing

对锥形方管进行无模拉伸基础实验研究.探讨各种工艺参数对锥形方管外形、断面形状和锥度变化的影响,分析方管无模拉伸时断面圆化程度的影响因素及影响规律,并提出减轻断面圆化程度的具体方法.研究结果表明,采用无模拉伸的方法可以加工带有一定锥度的锥形方管,锥管角精度在1.0%以内,加工后锥形方管的轮廓与控制曲线的计算结果一致性很好;方管拉伸断面形状膨胀率随着拉伸变形区宽度增大而减小;壁厚较大,断面形状膨胀率较小,当壁厚和变形区宽度都比较大时,几乎不产生膨胀现象.

Dieless drawing of tapered square pipe was carried out.The influences of process parameters on the variation of pipe profile,section shape and conical degree were studied.The influence factors and lawon the section rounding of square pipe were analyzed and the methods of alleviating rounding factor were given out.In the experiments,square section steel pipes were mainly used,and tapered pipes with large angles were obtained.The drawing precise can be conducted within an error of 1.0%in taper angle.The tapered pipe profile drawn by dieless drawing is in good agrees with the calculated ones.The expansion rate of section shape decreases with the increase of deformation width.The thicker the wall,the larger the expansion rate.When the wall thickness and width are all relatively large,the expansion is relatively little.