The automation enables unmanned work around the clock, even at weekends. The Zeiss Vista measuring machine is positioned in the foreground at the front of the system. © Zimmer & Kreim

Customers are also increasingly pushing for shorter delivery times. "This can only be achieved if we have optimized process chains ourselves," emphasizes Weigert. "And that also means that we have to streamline our throughput times and make them more predictable. This includes making better use of the capacities of our machines."

Weigert's team looked at several different systems at the time and examined the advantages of each in detail. In the end, they opted for a system from Zimmer & Kreim. "A key point was that we wanted to integrate our machining center, which we had for electrode milling at the time, into the automation system," explains Weigert. "The special thing about Zimmer & Kreim was that the automation specialists there took responsibility for the entire system, including the integration of the milling machine." Another plus point was the modularity of the system, which promised advantages in the event of subsequent expansion.

System solution

The experts from Brensbach were responsible for optimally configuring the system as a whole, creating the necessary interfaces and getting the system up and running. However, automation did not start with Chameleon. "We took more than a year - not just to evaluate the individual systems and manufacturers. But also to prepare our processes," explains Weigert. "First of all, the processes have to fit. It makes no sense to automate until everything is optimal. Otherwise you inevitably automate all the weaknesses of the previous processes at the same time. And the machines implement all the errors in the processes exactly." All processes at SD Formentechnik were therefore put to the test and optimized from a holistic perspective, even before the first automation element arrived in the mould makers' hall. This also affected the electrode design: some electrodes, for example, are designed differently today - tailored to the strengths of automation.

Automation started at the old site with an existing Zimmer & Kreim genius 601 die-sinking EDM machine, the Chameleon handling system, the Röders RXP600DSH, the Zeiss measuring machine and a racking element. This configuration alone considerably extended the unmanned running times of the machines. The integration of the milling machine also ensured a significantly higher degree of autonomy in the system.

New location

After the move in 2014, the original milling machine made way for a more powerful Röders RXP 600 DSH HSC machining center. "A Zeiss Vista measuring machine was added for measuring electrodes and workpieces," explains Weigert. "This now handles 95 percent of the presetting and exact geometry measurement of the electrodes. This allows the system to work with the current actual data."

A genius 1000 is also integrated into the automation system. It can be loaded manually. The Chameleon is not affected by this - it uses a different access to the machine. © Zimmer & Kreim

With the increase in orders and the ever larger volumes of the individual projects, the plant has continued to grow. Today, a second, significantly larger Zimmer & Kreim genius 1000 die-sinking EDM machine expands the possibilities for eroding to far greater dimensions. And the rack spaces have also been considerably expanded - the racks currently hold 190 electrodes and 11 workpieces, which can weigh up to 80 kilograms and measure up to 350 by 350 millimetres.

Set-up is done centrally via the loading station. "It's no longer a problem for us to keep the machines busy around the clock - even at weekends," emphasizes Weigert. "We work exclusively with skilled workers. Two operators ensure that the system is working around the clock." They supervise all of their projects from the beginning right through to the finished part, design the process accordingly, also construct the electrodes and take care of the programs for milling and countersinking.

System control

"One major advantage is the Alphamoduli software that controls the system," emphasizes Weigert. "The great thing is that here, too, everything comes from a single source. What's more, the software is very user-friendly, easy to understand and intuitive to learn." A one-week technology training course on site was all that was needed for the operators to start working, initially with the help of support.

The work is different than before - the work processes on the machine are decoupled from the presence of the operator. In addition, they now follow a largely standardized pattern. Overall, the work has become much more pleasant. Whereas the operator previously had to change the blanks by hand when milling, the Chameleon now does this. "It's particularly the tedious routine tasks that have been eliminated," explains Weigert. Nobody misses lifting the workpieces either. Weigert explains: "Now everything runs in the system and the Chameleon takes care of the handling." The quality of the workpieces has not suffered during automation: The continuously planned processes are trimmed for high component quality. And this is achieved - virtually automatically.

Flexible working

Flexibility has not suffered in the process - in the case of "fire department orders", the operators can choose whether they want to feed in the new order via the system or intervene manually. In both cases, running orders can be interrupted and the urgent parts can be pushed in between before the interrupted workpieces are replaced and seamlessly processed further. Priorities for existing orders can be changed quickly, as can preset values.

The Chameleon automatically inserts an electrode into the genius 1000. The double gripper ensures efficiency - on the other side of the gripper is the old electrode, which is returned to the shelf once the eroding work is complete. © Zimmer & Kreim

"The layout of the automation also allows the machine to be conveniently loaded manually if required, without conflicting with the automation," explains Weigert. "This is necessary for workpieces that exceed the maximum weight or size for automatic handling, such as the large genius 1000 eroding machine. While the Chameleon generally uses side access for the machines, the operator can load the workpieces from the front as usual."

Throughput times have been significantly reduced. "And our adherence to deadlines has improved significantly with the system," explains Weigert. "What's more, the automated processes eliminate the human error source." The Alphamoduli software tracks electrodes and workpieces via its RFID chips. "We have attached them everywhere," adds the production manager. "This means that it is no longer possible for the system to place an electrode in the wrong magazine location, change it incorrectly and render the workpiece unusable. The standardized automatic processes also make the processes significantly safer and more stable."

The plant is well utilized - even now, in coronavirus times. "At the end of 2020, we even had something of a small boom," explains Weigert. "With automation, we are now much more flexible and we can better compensate for fluctuations in incoming orders. This has brought more calm to our business overall. Automation has made us faster and better for our customers. Even if the time and cost pressure will continue to increase in the coming years, we feel we are well positioned for the future with our partner Zimmer & Kreim." Michael Huth / ds