Parameters Controlling Of Sheet Metal Flexible Forming Using Plasma Arc

Flexible forming of sheet metal is a technique applied widely in manufacturing fields, such as aerospace, automobile, shipbuilding, and chemical container industries. Traditionally, in sheet metal forming, a lot of time, money and human resource are usually cost to produce the mould and die according to the desired shape of the product. Especially, the cost for larger sheet metal would be higher. With the development of economy globalization and market diversification, industrial products are renewed more and more frequently, to develop which shorter period and fewer funds are needed. Investigating theory and technology of flexible forming without the need for mould and die contributes to significantly decreasing the high cost and long lead-time. In the versatile varieties and small-batch production, this technique has greatly potential advantages. Especially, in automobile industry, this technique can be used in flexible repair and modification for sheet metal of automotive or shaped objects. It can play important role in trial-manufacture of new sample automotive.Plasma arc serves as the heating source for its features of more economical, safe, agile and practical. Recently more and more investigators throughout the world focus on this newly developed forming method. However, the mechanism of the forming has not been investigated deeply. Thereby the forming results could not be accurately achieved by adjusting the processing parameters. On the other hand, the difficulty of predicting the forming results and choosing the processing parameters embarrass the practicality of Flexible forming using plasma arc. Therefore, in this paper to resolve the problems mentioned above the following items have been investigated:1. Metallurgical analysis of the formed sheet metal is executed on base of mass of experimental data. According to different bending condition the forming mechanism is explored. The decision criteria of positive bending and negative bending is summarized, which perfects the flexible forming using plasma arc mechanism;2. The on-line detection equipment of plasma arc flexible forming is set up to scale the bending angle accurately;3. According to sheet metals with different thicknesses, bending trend is investigated during the process;4. BP neural network is applied to flexible forming using plasma arc, inputs and outputs to the neural network are properly chosen. Multivariate function fitting of sheet metal bending is conducted using the trained BP neural network. On base of the work above, forming results predicting and processing parameters choosing are accomplished.In this paper, some key problems in flexible forming using plasma arc are discussed and solved. This will help generalizing the technology of FFUPA.