Quality Improvement on an Automobile Fender

One of the fenders made at a GM stamping plant had a long history of quality problems in the form of buckles in the corners of the eyebrow. As a result, the line had a high scrap rate, low uptime and poor stamping quality. The CGA analysis indicated that the prongs on the die prevented metal from being stretched properly. A redesigned die made in Kirksite achieved high panel quality and better material utilization. This paper explains the forming analysis leading to the die changes. The production line has experienced significant quality improvement and lower production costs since the changes were implemented.