Modified rotary tilt table for large production runs in Hyundai WIA machine tool from ARO-tec

Remscheid, December 2020 – Suppliers to the automotive industry work under enormous cost pressures and in a highly competitive market – something that contract manufacturing company AVCI in Solingen knows all too well. As a business that focuses primarily on the automotive sector, AVCI needs to produce in large volumes at the lowest possible cost. In its mechanical machining process for the special brackets used in the drives that power the hoods of convertible cars, the company has reduced hood weight by between 15 and 20 kilos by using die-cast aluminium components instead of thermoformed steel sheets. 

Until recently, AVCI used a five-axis machine to process these components, which involves adding holes at various angles, finishing contact surfaces and milling threads. "However, as this machine only had one machining station, it didn't allow simultaneous setup, so we decided to look at the alternative of a three-axis machine with a workpiece changing table so that we could also integrate additional two-axis rotary tilt tables", explains Lutz Wassem, Production Manager at AVCI. This approach would permit simultaneous setup and keep the machine in operation all the time, with virtually no interruptions. Non-productive time would be reduced to just two seconds during each workpiece change.

 Remscheid, December 2020 – Suppliers to the automotive industry work under enormous cost pressures and in a highly competitive market – something that contract manufacturing company AVCI in Solingen knows all too well. As a business that focuses primarily on the automotive sector, AVCI needs to produce in large volumes at the lowest possible cost. In its mechanical machining process for the special brackets used in the drives that power the hoods of convertible cars, the company has reduced hood weight by between 15 and 20 kilos by using die-cast aluminium components instead of thermoformed steel sheets. 

Until recently, AVCI used a five-axis machine to process these components, which involves adding holes at various angles, finishing contact surfaces and milling threads. "However, as this machine only had one machining station, it didn't allow simultaneous setup, so we decided to look at the alternative of a three-axis machine with a workpiece changing table so that we could also integrate additional two-axis rotary tilt tables", explains Lutz Wassem, Production Manager at AVCI. This approach would permit simultaneous setup and keep the machine in operation all the time, with virtually no interruptions. Non-productive time would be reduced to just two seconds during each workpiece change.

A major challenge during the realisation of this idea was the fact that AVCI needed to be able to mount a multiple-point clamping system – complete with appropriately sized interference areas – on the C axis of the machine, to enable the system to achieve high production volumes on each side. The asymmetrical design of the swivel bridges already on the market made them unsuitable for this application. The company embarked on a search for a provider that would position the face plate centrally rather than on the side, without compromising on stability. This design would provide a sufficiently large interference area.

AVCI contacted Bielefeld-based company ARO-tec, whose core business is the sale of machine tools from Hyundai WIA; the Solingen business was already an ARO-tec customer and had positive experience of the Hyundai WIA machines. Both Hyundai WIA and ARO-tec were very interested in the proposition and potential partnership. However, the partners faced another hurdle when they went on the hunt for a manufacturer of rotary tilt tables who was open to creating the custom solution they envisaged. "We made enquiries with multiple companies, but they all offered us their standardised modules, which were not what we needed", says Wassem. None of the companies that the partners approached were prepared to develop the solution they were looking for.

"Of course, there are providers who could sell us a complete processing centre with workpiece changing and a rotary tilt table, which would give us five-axis processing", adds Michael Kesterke, Sales Engineer at ARO-tec. "But none of these solutions were competitively priced". A more expensive solution would have significantly increased unit costs, which has a number of negative knock-on effects, particularly in the fiercely competitive automotive sector. But then ARO-tec and AVCI approached Remscheid-based company Peiseler, a leading manufacturer of trunnion tables, rotary tables, two-axis rotary tilt tables, swivel heads and workpiece changing tables known for its ability to develop sophisticated custom designs for its customers.

This turned out to be the breakthrough that the joint project needed. Peiseler was the only provider that was open to finding an appropriate solution. As an additional axis always takes up a lot of space, the aim was to design a compact and slimline component without compromising on stability. What's more, the solution needed to be plug-and-play, as the customer wanted to be able to quickly and easily remove the fourth and fifth axes, which rotate the workpieces, in order to use the machine tool as a standard three-axis machine in other applications. "Peiseler did an excellent job of implementing all of these requirements", emphasises Wassem.

To create the enlarged interference area, the designers in Remscheid extended the weighing housing with two modified cast caps on the right and left. The interference area can now have a diameter of up to 650 millimetres with one workpiece, compared to the previous maximum of 180 millimetres. Although the size of the workpiece is not relevant for AVCI, this design modification allows a hydraulic device with multiple clamps to be integrated into the machine, which enables multiple smaller workpieces to be machined adjacent to one another. This solution, combined with the use of a pallet changer, significantly increases number of units that can be produced while also reducing the manufacturing time.

"It is really wonderful that Peiseler worked with AVCI and us to develop such a great solution", emphasises Kesterke. The fact that the system in question is a workpiece changing table makes it all the more impressive. "Developing a rotary tilt table with an enlarged interference area, and using a new design based on modular elements from existing models, was completely new territory for us, too", says Markus Kocherscheid, the Sales Account Manager responsible for ARO-tec at Peiseler. Alongside the mechanical changes, seamlessly adapting the solution to the Hyundai WIA F 600 D control system was also something of a challenge. "Peiseler did an excellent job of establishing this connection to the machine tool and its electrical interfaces", Kesterke emphasises: "This step wasn't easy, but it was incredibly important".

Factoring in all of the testing stages, the Peiseler-equipped machine has now been running in three-shift operation for just over a year, producing an ever-changing range of components for automotive customers. "Thanks to this extraordinary technology, we benefit from the machine's high availability in continuous operation and from the higher production volumes we can achieve with it", says AVCI Production Manager Wassem. ARO-tec and Peiseler have met all of the customer's expectations, and the company was able to boost its output by 20 percent as a result of the investment. "We've also reduced costly downtime to virtually zero, which in turn makes us more competitive".

The partnership between the three companies was smooth, seamless and exceptionally productive. Peiseler made an important contribution throughout the project. "We had the ideas and Peiseler made them happen", says Wassem. Technological performance and high precision were also important factors; with rotary and swivel axes, every arc second counts. Alongside the company's openness to ideas and willingness to work on unusual custom solutions, its strong customer focus, technology, quality and performance were also key to the project's success. AVCI Production Manager Wassem and ARO-tec Sales Engineer Kesterke agree that Peiseler is an outstanding partner.