(Translation of press article by journalist Nikolaus Fecht issued in bbr)

Pre-punching and Forming System from ebu Umformtechnik

LONG-TERM CUSTOMERS often place high demands on their equipment suppliers. After many years of doing business together, they know the supplier's performance and innovative potential. In this way, sophisticated systems technology is almost always a collaborative effort. One example of this is the highly dynamic system for pre-punching and forming sheet metal blanks up to 1,100 millimetres wide, jointly developed by the OBO Bettermann Group and ebu Umformtechnik.

One look up in the OBO Bettermann production facility in Menden is all it takes: you see the rows of cable ducts and other products with which the Sauerlanders earn their money. Recently, OBO Bettermann has been producing ducts on the new pre-punching and forming system from ebu Umformtechnik GmbH, a company located in Bayreuth. The Bayreuthers have been producing systems for the Sauerland-based family business for nearly two decades. These include punching presses with ebu strip feeding lines, as well as ebu C-frame presses with manual feeding for the Menden site and the factory in Hungary.

The new, complete system is designed for punching and cutting coil materials with strip widths of 60 to 1,100 millimetres and strip thicknesses of 0.5 to 3.0 millimetres (maximum cross-section: 2,500 square millimetres). The coils weigh a maximum of 10 tons and have outside diameters up to 2,000 millimetres. The system functions with a maximum strip speed of 40 metres per minute. The new equipment is replacing an older system, which will move to the OBO plant in India. “The new system is not only taking over the punching tasks of the old one, it's getting new components that we've previously manufactured on a punch-nibbler system – but our volume of orders has increased so much that we need the new one to keep up,” says Philip Hünting, Industrial Engineering at OBO Bettermann. The performance is obvious: each and every day, staff in Menden process 40 to 50 tons of steel on the new machine over three shifts. Increased efficiency was not the only reason for the investment in a complete system, however. “It's easier for us to get all the technology from a single source,” says Christoph-Richard Gogolok, Deputy Production Manager for Profile and Punching Technology at OBO Bettermann.

One-stop solution trend

The demand for complete solutions like this is increasing – that is the impression you get when talking to Harry Wölfel, Sales Manager at ebu Umformtechnik. “We are increasingly being asked if we can supply the strip feeding line and automation,” he notes. “This is good news for us. We can also take it a step further, however, and integrate strip feeding lines from other manufacturers into a single solution.” The company's regular customer in Menden wants the “single source” solution, however, since, in Hünting's words, “we are reluctant to experiment with critical machinery.” The company plans investments critical to their profitability well in advance. After a round of tenders, ebu Umformtechnik was once again chosen as supplier. Initial planning discussions began.

Joint approach to optimal parameters

It is a conventionally driven flywheel machine whose stroke rates the team adapts to the components to be manufactured on the system. However, the final pre-setting of the parameters (e.g. strip speed and roller pressure) for the different materials and components took place on-site. “The initial set-up worked like a charm,” remembers Hünting. “We determined the speed together.”

One big challenge: space was at a premium, so the press had to be adapted to the existing foundation of the previous system. “The cramped conditions meant that we had to shorten the strip feeding line,” says Harry Wölfel, ebu Sales Manager. “This forced us to reduce the strip speeds and adapt the software to the strip loop.” Rapid and precise strip feeding is critical to OBO Bettermann.

Another ebu Umformtechnik specialty: assembling large systems like this not in the factory, but on-site, at the customer's location. “We build our systems as highly vibration-damping cast structures, which are assembled at the customer's site,” explains Harry Wölfel. “This also pays off when it comes to delivery, because the truck can run other time-saving and cost-saving routes than a heavy goods vehicle.”

Simplified coil device

One thing that definitely helps is the hydraulically operated loop bridge, which lifts to form a roller band between the straightening machine and the strip feed. It allows the fitter to safely advance the start of the strip over the loop pit. When the feed rollers have gripped the beginning of the strip, the loop bridge lowers into the loop pit, and the straightening machine conveys the material into the loop, from where it is fed to the press in continuous operation.

Future conversions already planned

In addition to high system availability and reliable operability, OBO Bettermann also values quick tool changes. This is possible thanks to a special tool change concept with a PLC-programmed sequence for setting the installation height. Specially developed tool-change consoles for the relatively narrow tool inserts from OBO Bettermann also reduce set-up times.