The tube expanding process is simplified as the deforming process.of a ring under internal pressure.Aspecific finite element analysis procedure is programmed to simulate the deforming process.

• 将焊管胀径过程简化为承受内压的圆环的弹塑性变形过程，编制了专用有限元程序对其进行了分析，计算出了胀径力；