All changes in processes can lead to further adaptations. When modern painting processes came onto the market in the early 1990s, BPW Bergische Achsen was one of the first axle manufacturers to use cathodic dip painting (KTL) – because it allowed for even better quality and higher corrosion resistance. Thanks to the KTL coating, for the first time it was no longer necessary to give the axle unit a top coat, which meant significant savings potential for trailer manufacturers. In parallel, KTL processes were also used for the first time in trailer production. The resultant process changes also posed a challenge for the BPW engineers: they had to find new solutions for tracking adjustment. “With dip-painting processes, it was no longer practical to weld the fully assembled axle unit onto the vehicle frame and then paint it together with the vehicle frame in a single operation,” explains Hans Werner Kopplow, at the time a development engineer and now head of the Electromobility Business Unit at BPW. “Previously, completely assembled air suspension axles were placed on the frame upside down and then welded on. Since the switch to dip-painting processes, supports are first welded to the vehicle frame and then the suspension is mounted after separate painting processes”.