Effect of clearance on wrinkling of thin-walled rectangular tube in rotary draw bending process

Abstract

The clearances between tube and various dies have a significant and complicated influence on the onset of wrinkling during the rotary draw bending process. To study the effect of clearance on wrinkling, a 3D finite element (FE) model of the process for thin-walled rectangular aluminum alloy tube has been built using the explicit code ABAQUS/Explicit and validated by comparing the experiment. Then, simulation and analysis of the process have been carried out based on the model. The influence laws of clearances between tube and various dies on wrinkling have been studied and the reasonable combination of clearances obtained using the combination method of 3D FE simulation and orthogonal experimental design. The results show that with the increase of tube mandrel clearance, Δcm, and tube bending die clearance, Δcb, the wrinkling wave number decreases rapidly, whereas the wrinkling wave height increases sharply. The effects of tube wiper die clearance, Δcw, and tube pressure die clearance, Δcp, on wrinkling are not significant. The reasonable combination of clearances is Δcm = 0.15 mm, Δcb = 0 mm, Δcw = 0 mm, and Δcp = 0 mm. These achievements are helpful to the design and optimization of the process.