The article studied the geometrical dimensions and surface quality of the shells in the deformation zone of piercing. 研究了穿孔变形区中毛管的几何尺寸和表面质量。
Based on the assumption, the computer was used to calculate the minimum deformation energy, and the speed distribution in the deformed area and the drawing force were gotten. 在此基础上利用流函数建立了变形区速度场，并利用计算机对变形能进行求极小值，得到了变形区的速度分布及拉拔力。
