Study On Drawing Process Of Front Wheel Cowling Of The Automobile

The wheel cowling is a typical outer automobile panel, the requirement of forming accuracy, surrounding dimension and finish are much higher. The wrinkles, cracks and other defects are easy to occur in the foming process for the workpiece's complex structure, smaller local fillet, larger forming arc and drawing depth. Therefore, the wheel cowling panel requirs high quality, it is difficult to control the forming process and hard to form the part.The value and loading mode of the blank holder force have a significant impact on the forming quality. Controlling the blank holder force effectively has become an important technique. By dint of the finite element software, this article focuses on the influence of the variable blank holder force(VBHF) loading mode on the forming quality. Firstly, deep drawing numerical model is designed according to the part's the structure and performance requirement. To avoid the large side force for one-piece forming and ensure the quality and dimensional accuracy, left and right parts are arranged symmetrically and formed in one die. On this basis, the stamping direction, the shape and structure of the binder face and the distribution of the drawbead are designed reasonally. Secondly, under the constant blank holder force condition, the wheel cowling panel's drawing process is simulated, optimal process parameters are obtained by using the orthogonal test. Thirdly, synthesizing the research results of the VBHF loading modes at home and abroad, eight typical loading modes are chosen and simulated respectively. By comparing the simulation results, U loading mode is regarded as the best option for the wheel cowling. Finally, the artificial neural network and genetic aigorithm are used to optimize the U load curve, and the optimal VBHF control curve is obtained. In this mode, there is no wrinkle and crack on drawing parts, the thickness distribution are evenly, the overall forming quality is better, which meets the design and use requirements.In this paper the VBHF control technology, the finite element simulation and the modern optimized technology are combined to solve the promblem that the wheel cowlings's low formability and forming quality, which offers a certain reference value for the die design and technical preparation of the similar automobile panels.