Modification and Implementation of a Dual-Variant Compatible Sheet Metal Welding Fixture for Flexible Manufacturing in a Live Production Line

The shift towards multi-variant production in the automotive industry has created a strong need for flexible manufacturing systems. This paper presents the modification of a welding fixture system to enable dual-variant production in an automotive Body-in-White (BIW) assembly line without changeover time. The existing fixture was redesigned using the 3-2-1 locating principle, incorporating reconfigurable elements and pneumatic clamping to ensure accurate positioning, stability, and repeatability during welding. The implementation was carried out in a live production environment without interrupting operations. Performance was evaluated through cycle time analysis across nine stations. The results show a reduction in cycle time variation and elimination of bottlenecks, leading to an improvement in line efficiency from 96.9% to 98.15%. The modified system successfully supports two different component variants on a single production line while maintaining dimensional accuracy and consistent weld quality. This approach demonstrates a cost-effective method to enhance manufacturing flexibility, improve resource utilization, and achieve stable production in high-volume automotive manufacturing and production environments.