Complex tools efficiently produced

Complex tools efficiently produced

With its direct drives, the NA1200 Essence achieves maximum precision. WÖLLNER + FRANZ has been successfully using this technology since 2010.

The history of WÖLLNER + FRANZ GmbH started in 1994 with the hiving-off of a larger company’s toolmaking activities. The move to premises newly built in 2004 and a workforce that has swollen to a good 50 employees are the outcome of continuous growth. In Halsbrücke in Saxony, Germany, WÖLLNER + FRANZ has made a name for itself as a supplier of punching, bending and follow-on composite tools. Distinguished by its high manufacturing depth and years of accumulated expertise, the company is a supplier to be relied on.

“New technologies soon become stan­dard in production.” Michael Wöllner, owner and managing director of WÖLLNER + FRANZ GmbH, knows what he’s talking about, quoting wire EDM as an example: “Such innovations open up totally new possibilities for design engineers and they relish ex­ploit­ing them.” As a specialist in punching, bending and follow-on composite tools, WÖLLNER + FRANZ encounters these trends at first hand. The increas­ing­ly complex follow-on composite tools are very much in demand because they help to reduce production costs considerably. For Michael Wöllner it is simply “part and parcel of the company’s customer-oriented outlook” to adjust in good time to changing requirements.

Commitment to comprehensive service

Service enjoys top priority at WÖLLNER + FRANZ and is something to which the company is wholeheartedly committed. Most affected by this are planning, design and production, where a balance is skilfully achieved between punctuality and the pressure of costs. This can be extremely challenging and calls for a good deal of flexibility, as Michael Wöllner notes: “We’ve had jobs where the design of an almost finished tool has been changed. In such cases, it’s often back to the drawing-board.” WÖLLNER + FRANZ is well equipped for such eventualities, which the managing director attributes to the company’s high manufacturing depth. “We handle everything internally – from design and programming in CAD/CAM, CNC-controlled turning, milling and grinding through to die-sinking and wire EDM. ”The only process entrusted to external service providers is hardening.

From the situations like the one just described, it’s obvious to the graduate engineer that his customers must also be under enormous deadline pressure. “We’re service providers to component suppliers in all branches of industry. At the moment, of course, they’re glad of any work they can get and are quick to respond.” However fast moving business is, WÖLLNER + FRANZ stays true to its customer orientation and provides its comprehensive service not only up to product delivery, but also beyond. “We don’t immediately write an invoice whenever we have to send out a fitter to the customer,” Michael Wöllner stresses. He considers this approach necessary if he wants to keep his customers and stay competitive.

Although WÖLLNER + FRANZ wasn’t left unscathed by the events of the past year, current trends are a source of optimism for Michael Wöllner. “The level of orders is such that we are now operating with two shifts and a third unmanned shift.” The managing director stresses that they still have unused capacity and looks ahead: “When the order situation becomes stable, production will soon be back to the old level.”

Wire-eroded components are indispensable for punching, bending and follow-on composite tools.

Superior quality and extended capacity with advanced wire erosion

Nevertheless, the level of orders is not entirely responsible for the vacant ca­pac­i­ty. In fact, WÖLLNER + FRANZ has invested in wire erosion over the last few months, and the toolmaker has thus taken a huge technological leap forward. The FA10-S Advance installed in 2009 was followed by an NA1200 Essence from Mitsubishi Electric at the beginning of 2010. “The original plan was to give back the FA10 in return for the NA1200,” says Michael Wöllner in retrospect. However, in the end he was swayed by the extra capacity of the two machines.

FA10-S Advance and NA1200 Essence are WÖLLNER + FRANZ’s first wire-cut EDM machines from Mitsubishi Electric. His staff didn’t experience the changeover to a new manufacturer as an obstacle, he claims. “The differences from the ten-year-old predecessors would have been major, whatever the make,” Michael Wöllner confesses. The example of Mitsubishi Electric shows in addition that new doesn’t necessarily mean more complicated, he adds. On the contrary: “The machine controls make use of the Windows interface. Anyone familiar with computers will therefore quickly learn how to use the software.”

The machines from Mitsubishi Electric are not only easy to operate, but they also support the toolmaker with a whole range of preset parameters. “We machine a huge range of metals and would normally have to define numerous values for the respective program each time in order to achieve the desired results,” Michael Wöllner explains. “Mitsubishi Electric has programmed so many parameters that we’re either relieved of this task entirely or, in the case of very exotic materials, only have to make at most slight modifications.”

Exact positioning of the wire by remote control.

„The original plan was to give back the FA10 in return for the NA1200 …“

Innovation for the future: Wire erosion with direct drive

The technological step forward that WÖLLNER + FRANZ has taken with the two new wire-cut EDM machines is huge. Their higher cutting rate accelerates the process and boosts productivity. The improved surface precision reduces the number of necessary downstream cuts, which is also a boon to productivity. The machining of hard metal and the use of thinner wires with diameters of 0.1 mm are further factors from which WÖLLNER + FRANZ have profited. “What really impressed us, though, is the new machine strategy of the NA1200 Essence,” Michael Wöllner adds.

There’s a trend towards follow-on composite tools because they boost productivity and cut production costs.

With its tubular direct drives, the NA1200 Essence is extremely precise with its positioning

The NA series from Mitsubishi Electric represents a further evolutionary step in wire erosion. The basis of this innova­tive system is the load-free tubular direct drive with ultra-fast communication by fibre optic cable between the control, axis amplifiers and drives – a technology known as Swift Optic Communication. Michael Wöllner sees clear advantages here over other machines: “Response behaviour is more dynamic, faster reacting and more precise.” Furthermore, direct drives are non-wearing and hence much more dependable, he adds.

Powerful selling points: Advice, price-performance and after-sales service

Mitsubishi Electric’s after-sales service has proven to be extremely reliable, Michael Wöllner finds. “Our contacts are very forthcoming, both technically and commercially,” he says in praise of the manufacturer. It was not least the expert advice and good price-perfor­mance ratio that contributed to the purchasing decision. The managing director hasn’t regretted the investment, because with the new generation of machines Michael Wöllner sees his company ideally equipped for future orders. “Wire EDM is existentially important for us for the production of active parts in the tool. There’s no more efficient and at the same time more precise production method.”

3D-design of the tool components accompanies each job.

Interview