Application of the preprocessing system of stretch forming over multi-point tooling in real factory environment

A preprocessing system of stretch forming over multi-point tooling is introduced and its application method is described in detail. The system includes the functions of original die surface generation, pin height calculation, blank generation and load path generation. According to the digital model of the part, the original die surface, blank and load path can be calculated and then be integrated into available finite element system to optimize the die surface. Furthermore, the pins height data of the optimal die surface are calculated by the preprocessing system, with which the optimal tooling configuration can also be gained by adjusting the pins of multi-point tooling. Then, parts can be stretch formed over multi-point tooling. With the above basic application principle, two aircraft skin parts are produced by stretch forming process over multi-point tooling. The measured results show that the precision of the two productions can both meet the requirements of the parts. The preprocessing system is available in the factory environment and constitutes an important module of the factory system for stretch forming over multi-point tooling.