管材弯曲有限元仿真分析及试验研究

利用有限元仿真分析方法对管材弯曲成形过程进行数值模拟,指出了弯曲过程中开裂、起皱、截面畸变等缺陷,分析了弯曲区域内管材壁厚变化规律.在此基础上进行工艺试验,并对试验后管材壁厚进行分析.试验结果与仿真分析结果吻合良好,两者均表明,弯曲过程中,弯角外侧管壁肇厚减薄,弯角内侧管壁壁厚增加,最大减薄和最大增厚均处于弯角中间部位.管材弯曲过程中,弯角外侧平均壁厚应变ε_t随着相对弯曲半径R/to的增大而减小;当R/to过小时,管壁外侧会过渡减薄,甚至破裂.

Finite element simulation and experimental analysis of tube bending

FEA was used in the bending process. The zone was picked out where the crack and wrinkle happened, and at the same time, the thickness in bending area was analysed. On this basis, the technical experiments were carried out and the thickness distribution was made clearly. The experiment results coincide with the FEA greatly. Both of them show that the thickness of outer tube descends and the thickness of inner tube goes up. Furthermore, the greatest thinning and thicking both are in the middle of bends. During the bending process, the average ε_1, will decrease with the increasing of relative bending radii R/to. The extra thinning and even the cracking condition will occur if the value of R/to is too small.