Tier 1 auto suppliers navigate E-mobility landscape with automated welding

The manufacturing move from internal combustion engines (ICE) to battery electric vehicles (BEV) and e-mobility is here, but that transition means more than retooling for a different kind of drive unit. This is a sea change in automotive manufacturing that will have seismic top-to-bottom implications for the entire industry, especially for Tier 1 automotive suppliers and in particular the automated welding processes they use to join parts.

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Of the 20 largest automotive OEMs, 18 have committed to increased BEV sales, and some OEMs are retooling to make all or a significant number of their vehicles electric beginning in 2030.1 Despite that pledge, the reality is that there are currently few, if any, mainstream manufacturing processes established for a sizeable portion of the coming BEV market. The initial challenge is to devise new manufacturing solutions for what are still emerging technologies. Such a scenario offers huge opportunities for Tier 1 suppliers.

To make a cost-effective, profitable conversion from ICE to BEV, manufacturers must rethink design, fabrication, and assembly from the ground up. For example, the mass of a BEV’s high-performance, long-range batteries adds substantially to its overall weight. That additional load must be countered by incorporating lighter, stronger materials such as aluminum and plastics into the vehicle, which, in turn, directly affects manufacturing processes and applications, especially in the realm of material joining. New materials require new approaches.

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The role of Aluminum, for example, in Tier 1 manufacturing continues to increase, and, in many cases, it has become indispensable due to its strength to weight ratio. Aluminum is now used extensively to fabricate battery housings and liquid cooling plates, heat exchangers and chassis components. Welding aluminum, however, has its challenges. Aluminum has a very low melting point, four times the thermal conductivity and twice the thermal expansion of steel. Aluminum welding also tends to produce a surface-level oxide layer that requires secondary laser, mechanical or electrochemical cleaning processes for removal.

To provide new aluminum parts and products for the BEV sector, Tier 1 suppliers must devise and adapt part production methods and strategies for which there are currently no blueprints but must remain profitable, nonetheless. It will take more than merely adopting new technology and automation; it will take an experienced partner.

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KUKA is an original when it comes to robotic welding, and its advances in aluminum welding and joining processes are moving the future of Tier 1 manufacturing. Industry experience translates to reliability, and that paired with innovation, will be essential to meet the changes faced by Tier 1 auto suppliers.

KUKA has integrated seamlessly to establish long-standing partnerships with some of the world’s leading aluminum GMAW (MIG) welding power supply developers and provided sophisticated and proven robot technology such as KUKA.RoboSpin and KUKA.EqualizingTech software packages to make aluminum resistance welding more efficient and productive. KUKA.RoboSpin improves spot welding quality by rotating the robot around the tool center point during the weld. This rotation eliminates the typical tip adhesion effect when mechanical force is applied, improving weld quality, decreasing cycle times, minimizing tip wear, and reducing downtime.

KUKA.EqualizingTech compensation software supports the correct positioning of the weld gun relative to the component by means of robot motion. It also allows the weld gun to compensate for position deviations that occur due to flexing of the gun arm, electrode tip wear or deviations in component position. By compensating for these factors, residual forces acting on the workpiece are reduced, and complicated commissioning required for pneumatic compensation systems can be eliminated. The elimination of conventional compensation system components also saves Tier 1 suppliers investment costs and reduces maintenance requirements.

Along with new processes, BEV manufacturing will require Tier 1 suppliers to work with new material applications and explore alternative joining methods to maintain production levels and profit margins.

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Fabrication of aluminum battery trays, for example, is uniquely suited to Friction Stir Welding (FSW), and KUKA’s continuous path robotic-based FSW maintains a decisive advantage in joining non-ferrous metals with low melting points and mixed-material combinations. Sophisticated calibration algorithms ensure welds are executed exactly with high seam strength, comparatively low heat input and no welding defects. Matched with KUKA’s new Process Control and Documentation System (PCD), manufacturers are assured of 100% real-time quality monitoring, process reliability and reproducibility, essential factors for scalability and customization.

In addition to FSW, laser welding – focusing a high-energy laser beam on a small spot with the aid of optics – is suitable for high-speed welding of components that require a narrow weld seam and low thermal distortion. Compared to traditional arc welding, laser welding produces lower unit costs due to its speed, provides precise control and can be used on new material combinations such as copper-copper and copper-aluminum.

As important as innovative technology and reliable performance will be to Tier 1 suppliers, manufacturing support and collaboration will be essential. Providing a single-source end-to-end solution on a given process will be fundamental to success. KUKA is a proven end-to-end provider that provides start-up consultation and planning, process commissioning and ongoing testing and evaluation for continued optimization. Tier 1 suppliers that are nimble, able to get new and novel applications online faster than their competitors and hone their manufacturing for enhance production will be the first to capitalize on e-mobility manufacturing.

For maximum product development and production flexibility, Bavarian automation specialist SAR partnered with KUKA to develop a fully automated production line for the assembly and installation of a BEV electronics module – the vehicle’s central electrical control unit and heart.

SAR had to create an extremely agile system with a high flexibility due to the nature of the emerging BEV market. With a new concept, virtually all aspects of the vehicle, other than overall dimensions, stand to be changed and refined, creating the need for production processes with maximum resilience.

SAR incorporated 11 KUKA robots, including the KR AGILUS and KR CYBERTECH, into its 28-robot production line to automate all fabrication tasks from screw-fastening and bonding to module inspection and installation. The challenge was to find intelligent solutions where neither process blueprints nor best practices had been established. Ultimately, the company found the automated robotic system to be highly scalable and customizable.

The emergence of the BEV market alters virtually every sector of the automotive manufacturing landscape, especially that of Tier 1 suppliers, who will take on increasingly more pivotal roles in fabrication process design, development, and refinement for the components they supply. In many cases, this evolution will break new ground and require suppliers to adapt new technologies and partner with industry leaders who can join forces to meet the upcoming challenges.