PSA PEUGEOT CITROËN use PAM-STAMP for Successful Roll Hemming Simulation on Vehicle Assembly Lines
We are now able to test several product/process configurations with PAM-STAMP and provide very early orientation to our technical choices. Previously, we would have had to wait to perform tests with physical tools, which would sometimes come a bit late for in-depth changes. The benefit is clearly a decision aid to define more robust processes early in the design process.Joëlle GarabedTechnical Leader of the Digital and Simulation Stamping Department / PSA Peugeot Citroën
A need born of process transition
When it became clear that roll hemming would soon replace the traditional table-top process for the assembly of vehicle opening panels, PSA Peugeot Citroën immediately saw the need for an appropriate simulation tool. And since such a tool was not readily available on the market, it found in ESI the perfect partner to join in the challenge of developing one based on its proven PAM-STAMP solution.
As the technology was recent, PSA Peugeot Citroën did not have significant experience to build on. The expected output of this 1.5 year-long collaboration was to anticipate major sheet metal behavior defects including unwanted deformations and folds.
The simulation tool had to be able to perform complex trajectories and accommodate various roll profiles in order to render accurate material shaping. This would ultimately allow the precise design of doors, hoods, back-lids, trunks, and other components early in the development phase of future vehicles.
A collaboration to build a customized process-oriented simulation tool
To achieve this goal, PSA Peugeot Citroën shared with ESI its real industrial data and its actual industrial needs. Technical engineers at PSA also carried-out the necessary physical prototype testing to establish and fine-tune the correlation between workshop reality and digital simulation.
This collaboration based on mutual exchange and understanding led to a clearly process-oriented software solution with input parameters such as roll profile, roller angle, and trajectory, providing answers to real problems and not just numerical cases. The product effectively addresses the needs of experienced hemming professional seeking ways to improve his process. It is truly a product tailored for an engineer designing or fine-tuning a hemming station.
First, roll hemming simulations were performed on the wing of a vehicle currently under development, on which the borders were closed too tightly according to product design. After reviewing the trajectory through simulation, it was decided to reshape the stamped sides and to readapt the roll hemming trajectory, which resulted in a side closing compliant to the target.
A more delicate challenge was then addressed: on the tip of the wing, a very tight radius was generating unwanted burrs and folds. With the help of PAM-STAMP , several iterations were carried out working on side height and roller trajectory to end up with an assembly closer to the target and without folds or burrs. This simulation served as basic input to set up the process, without ever requiring a physical tool.
The partnership continues
As Phase 1 – the collaborative project described above –comes to an end, PSA Peugeot Citroën has trained its assembly personnel as well as upstream designers to take advantage of this new tool earlier in future vehicle developments. Other teams are also at work to integrate this simulation in the standard industrialization process. The software development achieved is available in PAM-STAMP Version 2009. This leads naturally to Phase 2 of further collaborative development with ESI to increase the solution’s possibilities and reinforce post-treatment.