Automotive suppliers are under particular cost pressure and face above-average competition. This also applies to the contract manufacturing company AVCI in Solingen, which specializes in metalworking and is primarily active in the automotive sector. This always involves series production with high quantities that need to be manufactured as cost-effectively as possible. This is also the case with the mechanical processing of special brackets for convertible top drives. Whereas these used to be made from deep-drawn steel sheets, the use of die-cast aluminum parts now enables considerable weight savings. Previously, AVCI used a 5-axis machine to machine them, for example to carry out the necessary drilling, re-milling work and thread milling. "However, as this only offered one machining station and therefore no set-up parallel to machining time, we considered upgrading a 3-axis machine with a workpiece changing table with additional two-axis swivel devices as an alternative," says Lutz Wassem, Production Manager at AVCI. This would allow the machine to be set up parallel to production and be in almost constant operation. The non-productive time during the workpiece change would be only seconds.

A major challenge in implementing this idea was AVCI's requirement to be able to mount a multiple clamping device with appropriately dimensioned interference circuits on the C-axis on each side for the production of large quantities. The swivel bridges available on the market were out of the question due to their asymmetrical design. It was therefore necessary to find a supplier that would not position the faceplate laterally, but centrally, while maintaining stability and thus offering a sufficiently large interference circle. With this in mind, AVCI turned to the Bielefeld-based company Aro-tec, which sells Hyundai WIA machine tools in its core business and with which the Solingen-based company has had good experience. Both Hyundai WIA and Aro-tec showed great interest and a willingness to cooperate. The joint search for a supplier of swivel devices that was open to the desired special solution proved to be more difficult. "There are suppliers who offer a complete machining center with workpiece change and swivel device and therefore five-axis machining," says Michael Kesterke, Sales Engineer at Aro-tec. "But they couldn't keep up in terms of price." Aro-tec and AVCI then approached the Remscheid-based company Peiseler, a manufacturer of turners, rotary tables, two-axis swivel devices, swivel heads and tool changing tables, which is also known for developing complex special designs.

Higher quantities in less time

Peiseler was open to finding a suitable solution. As an additional axis requires a lot of space, the premise was to build it as small and slim as possible without compromising stability - and as a plug-and-play solution. The fourth and fifth axes, which enable the workpiece to be turned, had to be easily removed in a short space of time so that the machine tool could also be used as a normal 3-axis machine. "Peiseler has implemented all of this brilliantly," says Wassem. The designers extended the cradle housing with two modified cast hoods on the right and left for the larger interference circle. Instead of the original maximum diameter of 180 mm, this can now be up to 650 mm for a workpiece. Although the size of the workpiece is not relevant for AVCI, this structural change allows the installation of a hydraulic device with several clamping nests. This makes it possible to process several smaller workpieces next to each other. This and the use of a pallet changer enable a higher number of pieces to be produced with a reduced production time.

"The fact that Peiseler has developed such a suitable solution in cooperation with AVCI and us is truly exceptional," emphasizes Kesterke. "The development of a swivel device with an enlarged interference circle and the first-time implementation of such a variant design from existing modular components was something new for us too," says Markus Kocherscheid, who looks after Aro-tec in the sales department at Peiseler. In addition to the mechanical changes, the seamless adaptation to the control system of the Hyundai WIA F 600 D was a certain challenge. "Peiseler managed this connection to the machine tool and its electrical interfaces excellently," says Kesterke. The machine with the Peiseler swivel unit has been running in three-shift operation with changing components for a good year. "Thanks to the exceptional technology, we benefit from the high availability in continuous operation and the significantly higher quantities that are possible as a result," says AVCI production manager Wassem. Overall, this has enabled the company to increase output by 20 percent. "And at the same time, we avoid the cost-intensive non-productive times almost completely."

Cooperation and commitment as success factors

The collaboration between all three companies ran absolutely smoothly and was very productive. Peiseler was heavily involved throughout the entire process. "We had our ideas and Peiseler realized them," says Wassem. The technological performance and precision were also important. Another decisive factor was the openness and pronounced willingness to provide unusual special solutions, as well as the customer focus, technology, quality and performance. AVCI production manager Wassem and Aro-tec salesman Kesterke agree that Peiseler is a very good partner.