The robot and the saw

Circular cuts on sectional rods belong in the repertoire of all metalworking companies. Here, a Kuka industrial robot guides a Meba band saw along the optimal curved cut through the most diverse cross sections.

Flexible solution for a complex operation

Innovation by Wieland for Wieland: This tailored solution from Wieland Anlagentechnik is revolutionising the pointing of sectional rods. Here, metals are cut to the optimal effect by a metal hand, for higher quality – and greater efficiency and productivity to boot.

For many years, metalworking companies have been faced with growing requirements affecting production flexibility, from the smallest piece numbers to major series runs, the processing of diverse materials and measurements, and quality. Global competition forces them to find flexible and powerful solutions that can manage a wide range of production tasks, yet still remain efficient. Against this backdrop, Wieland Anlagentechnik GmbH in its capacity as a special machine builder has specialised in designing and tailoring plant and machinery precisely to its customers’ needs. For the Wieland BU Extruded Products in Ulm, Wieland Anlagentechnik developed a concept that was unique at the time: an innovative combination of machine tool building and robot technology that optimised the then manual cutting processes on a complex component.

Robot and band saw: a dream team

To point profiled bars, employees had to guide long workpieces manually through a band saw. “This meant for the worker high physical strain, not to mention inconsistent qualities,” explained Harro Reiff, Head of the Production Department for the Wieland Business Unit Extruded Products. The challenge facing the system builders lay in the high complexity of this operation, which is to provide a parabolic edge to the workpiece ends that can then be processed further on a draw bench. For instance, not all metal bars can be aligned, but only secured in place with clamps. The obvious solution of cutting the point with straight edges, like a pencil, was ruled out in this case. “We then arrived quickly at the idea of combining a robot with the band saw. Its high flexibility makes it the ideal choice for making curved saw cuts in varying cross sections,” explained Tobias Ziesel, Marketing and Sales Manager at Wieland Anlagentechnik GmbH.

As the interface between production planning and actual production, the system builders analyse precisely each and every time what is of key importance to the customer. “If the highest precision is required in production, we develop the right solution. If, on the other hand, the customer’s machining task places precision in a subordinate role, focusing instead on other requirements, we develop a plant that provides just that. And the automation concept, too, is adapted accordingly,” explained Ziesel.

Sawing in the third dimension

The solution involves a Kuka industrial robot whose integrated camera detects the exact location of the workpieces fed into the machining chamber. By analysing these data, it determines the optimal cut. After two to four cuts at the specially optimised Meba band saw, a roller, adjusting likewise to the workpiece’s location, starts up, securing additionally the point in place. All of the system’s functions are programmed via a digitised twin, which also controls the feed and roller. “Together with Wieland, we have developed a postprocessor that is used to simulate all functions via the twin and so program the system offline,” explained Ziesel.

The pointing process therefore runs fully automatically. Over a hundred different kinds of profiled bar can be machined easily on the system. This operation then gained not only in ergonomics, but also in efficiency. “We achieved a considerable boost to reproducibility and better quality,” explained Reiff. “And not only that: we could increase greatly both product length and piece weight since this system was commissioned.” It therefore becomes clear: This innovative combination of highly dynamic band saw and flexible robot is a genuine benefit to the production of profiled copper bars at Wieland.

At a glance

• Wieland Anlagentechnik develops a fully automated system with a robot guiding a band saw
   
• More reliable, more ergonomic, and more efficient than the manual workstation
   
• Higher, unvarying quality and productivity