Design for Intelligent Variable Blank Holder Force Hydraulic Control System of the Frame CNC Hydraulic Press

In the deep-drawing process of sheet metal, accuracy, consistency and formability of products always determined by the variable blank holder force (VBHF). So, the accuracy of predicted reference input VBHF curves, the response performance of hydraulic actuators, and the tracing performance of machine controller are key technologies which determine the control performance of VBHF. Firstly, outline of an intelligent multi-cylinder VBHF hydraulic control system is proposed for a frame CNC hydraulic press. Then, detail designs on each module are given, such as the intelligent VBHF prediction module based on artificial neural network (ANN) and finite element method (FEM), the optimized hydraulic control module based on simulation and complex method, PLC control module based on PID and man-machine interface module based on MCGS. Finally, the availability of design and the improvement on performance of this system are confirmed by tests on the physical prototype of 12500KN frame CNC hydraulic press in Jinan Casting and Forging Cooperation.