Abstract: In view of automobile panel parts with complex surface, a new convex surface drawing method is put forth based on the traditional whole-surface drawing process. Considering that only the convex parts of punch and die working surface contact with blank during drawing, forming limit diagram(FLD) and the contact area distribution diagram between punch or die and blank are acquired through stamping simulation. The corresponding elements of wrinkle area and double-sided contact area are removed from the grid model, and the single-sided contact regions with small and lathy area are merged and convert into double-sided contact regions. The curves, each is fitted through the outermost nodes of the rest single-sided contact regions that aren’t merged, are imported into CAD to trim working surface of punch and die to obtain the convex surface, the example shows that the convex surface drawing process put forth can decrease the punch and die working surface area and it can reduce the production cost of the drawing die, while maintaining drawing quality.

Key words: automobile panel, convex surface drawing, stamping