Papers by Author: Wen Zhi Fu

Abstract: Springback is an inevitable phenomenon in multi-point forming, it affects the forming accuracy seriously. The precision of formed parts can be improved by modifying the die profile. The method of springback compensation for multi-point dies which formed cylindrical parts was studied utilizing theoretical analysis, numerical simulations and experiments. In order to accurately form cylindrical parts with specified parameters, the springback compensation formula of multi-point dies was studied. The upper and lower dies were adjusted according to the formula. Comparing the formed parts obtained from numerical simulation and experiment with the target part, the results show that this method can control the forming error within 1 mm guiding the forming process of cylindrical parts in practice, the problem of shape error caused by springback was solved effectively.

Abstract: Flexible-bending is an advanced bending method, especially suitable for small batch production of tubes. The shape of forming parts is mainly related to the offset of the bend die instead of the geometry of it. Based on flexible-bending technology, 3D bending of tubes was carried out by finite element method and the effects of primary parameters on the bending results were studied. The analysis results showed that3D continuous bending of tubes can be obtained by flexible-bending process; die offset, offset speed and feeding speed of tube have a great influence on the bending effect. Bending experiments of 3D tube were carried out by flexible-bending equipment and bending radii of the forming part were measured, the results were very close to that of simulations which proved the effectiveness of simulation.

Abstract: Although multi-point forming (MPF) is an advanced processing technique and has been investigated comprehensively as a metal working operation, there are few papers published to deal with MPF of polymers. The present paper reviews the features of MPF and evaluates the possibility of producing polymer components by means of MPF. The experimental research work makes use of PC sheets with a thickness of 3.82 mm. Numerical simulations were performed with the software ABAQUS, then spherical and saddle-shaped components were manufactured by MPF. The geometrical deviations between shaped components and their original CAD/CAM models were obtained to investigate the forming accuracy. The results confirm that MPF of PC sheet has potential for the manufacture of complex components.