Simulation of Hemming Process

Hemming is a well-known technology used by the automotive industry to join inner and outer door panels. The accuracy of the operation affects significantly the appearance of the car’s outer surfaces. Any defects such as surface deflection or twist may result in costly decisions; for example, the product may be rejected during the final stage of production.
 
There are severe difficulties in the simulation of such problems - in addition to the large deformations, there are difficult contact conditions. In our simulation, ninety 9-node u/p elements are used for the outer panel and 43 elements for the inner panel. Despite the complexity of the process, a stable convergence in the incremental solution was achieved.