Finite Element Analysis And Experimental Research On Deep Drawing Process For Cylindrical Cup And Conical Cup Based On Radial Segment Blank Holder

Using new process is an effective way to improve the formability of sheet. Studieshave shown that the radial segmental blank holding technology can effectively improvethe blank holding effect. The calculating work was heavy in previous research becausethe process parameters were selected by the brute-force method. And the study objectswere mainly cylindrical parts. When the block number is increased, utilizing the radialsegmental blank holding technology for the conical part and how to optimize the processparameters are of practical significance to the further research of the radial segmentalblank holding technology.In cylindrical parts, for example, the thickness gradient variation in the flange of thesheet metal is analyzed by finite element simulation. That is, the thickness gradientreduces from the inner edge of the flange to the outer edge of the flange along the radialdirection. It is shown that the larger thickness gradients is, the larger quantity ofsegments should be divided.The orthogonal experimental method combined with the finite element simulation isutilized to analyze the main effect of the process parameters of radial segmental blankholding technology (i.e. the block position of blank holder, the distribution of blankholding force (BHF) and BHF) and optimize the process parameter. The simulation resultshow that when the diameter of blank is220mm and the thickness is1mm, the subsectiondiameter of double blank holders is156mm, the ratio of the outer and inner BHF is1:3,the subsection diameter of three blank holders are148mm and172mm respectively andthe ratio of the BHF from the inner and outer is1:5:3, while other conditions being equal,the effect of blank holder is the best.The influence of the radial segmental blank holding technique used in the deepdrawing of the side-wall of conical part is analyzed by the finite element software ofDynaform. The results show that the forming effect of conical part is the best when theBHF is applied down to the side-wall and up and down at the same time to the side-wallfor the deep drawing of the blank which the diameter is85mm and the thickness is 0.2mm. And the deep drawing effect is significantly better than that by the conventionaldeep drawing process.The results of finite element simulation are verified by the deep drawing experimentof cylindrical cup by using the radial segmental blank holding technique. The resultshows that the effect of the double blank holders is better than that of the whole blankholder. When the ratio of the outer and inner BHF is1:3, the effect is the best. The resultsof simulation and experiment are in good agreement.