大口径白铜管偏心扩径的数值模拟

Numerical Simulation of Eccentric Expansion of Large-Diameter Cupronickel Pipe

基于Deform-3D有限元软件建立了Φ278mm×9.0 mm大口径白铜管的无外模扩径拉拔模型,研究了芯模偏转对扩径管材变形规律及管形和尺寸的影响。结果表明,偏心扩径过程中,应变在管材周向分布不均是由于管材各部分受力不均引起先变形区产生大变形和后变形区产生小变形导致的;随着芯模偏转角度从0°、2°、4°增大到6°,管材的圆度越来越差,壁厚偏心率也逐渐增大。

In this paper,a drawing model without external die ofΦ278mm×9.0mm large-diameter cupronickel pipe is established based on Deform-3D finite element software.The influence of the deflection of mandrel on the deformation rule and the shape and size of the expanded pipe is studied.The results show that the non-uniform distribution of strain in the circumferential direction of the pipe is caused by the non-uniform stress of each part of the pipe,which leads to the large deformation in the first deformation zone and the small deformation in the second deformation zone.As the core deflection angle increases from 0°、2°、4°to 6°,the roundness of the pipe becomes worse and worse,and the eccentricity rate of the wall thickness gradually increases.