Research On The Accurate Surface Construction Of Automobile Panel Drawing Die

Spot rate of the die is an important index in the process of die debugging. Mostdeep drawn products are parts of the automobile panel, such as engine hoods, doorpanels and fender panels. For these products, the geometrical tolerances are tight, andthe spot rate is generally required to achieve more than90%. However, the diedebugging is carried out by bench worker manually, and almost relies on engineeringexperience. The application of simulation can detect problems as early as possible toimprove the die design, thus it greatly shorten the debugging time and reduce costs.Based on stamping simulation, the reconstruction method of accurate die surfaceis put forth to improve spot rate in the drawing process of automobile panel. Accordingto the thickness values of nodes, which is from thickness distribution of the part afterstamping simulation, and applying the method of gird mapping, shape functioninterpolation calculation, node translation, the gap between punch and die grids isadjusted to be consistent with the thickness distribution of the part and accurate diegrids constructed through the method can be fit the thickness distribution of the part.Based on adjusted punch and die grids, the control points of the die surface and thecorresponding trimming curves are moved according to the translation values of thenodes and auto deformation of the surfaces with the change of the girds are carried out,the accurate surface of die through the method can fit the thickness change of the partafter drawing, consequently, spot rate of the die can be improved in the die design stage.This paper puts forward a method of the accurate surface construction ofautomobile panel drawing die, and the main work is as follows：1. According to the relationship between the thickness distribution of the partafter stamping simulation and the gap between punch and die, a method of the accuratesurface construction of automobile panel drawing die is put forth to improve the spotrate of the die in the die design stage.2. Based on stamping simulation, programs are written to realize the algorithmsof grid mapping and a method of the accurate surface construction of automobile paneldrawing die grids is raised.3. Based on adjusted punch and die grids and the control points of the die surfaceand the corresponding trimming curves, the accurate surface of die has been constructedto fit the thickness change of the part after drawing.4. Taking the drawing die of a car`s front cabin beam for example, the accurate die grids are built and then the accurate die surface is reconstructed.By the deviation analysis between the accurate surface and the primitive surfaceof the die, we can conclude that the method of this paper can improve the spot rate ofdrawing die in the die design stage, which has a certain significance for engineeringapplications.