C 42 U MT - C 400 U - HS flex | Der Span | precision machining for food and medical technology
No corners or hidden edges – those are just two of many requirements for components that are used in food processing machines. Der Span is a company that manufactures these components using Hermle machining centres. Thanks to HS flex automation, some of these machines are in use around the clock, creating perfect surfaces even overnight.
Hipster glasses, cap and faded jeans – If you met Matthias Reh, you would not suspect at first you were sitting with the founder of a successful company. The 32-year-old began his career with a leading international technology company. He completed his apprenticeship to become an industrial mechanic there and worked in tool building. In 2013 Reh decided to take a step towards self-sufficiency. He bought a small machine park for metalworking and moved into an empty industrial building in Waltenhofen near Kempten. This was not a completely naive move on his part. "My father was involved in his own special machine building business for a long time and I got used to living independently from an early age," explains Reh. Along with his father, three employees support him today. When asked how he came upon the company name "Der Span" (German for "The Chip"), He points to a large photograph of a single metal chip. "While I was looking for a name, I remembered having seen this picture at a Hermle in-house exhibition, and I thought it was very fitting," grins the young entrepreneur.
Initially his contacts to his former employer were helpful. He manufactured simple workpieces like brackets for him. "08/15 parts" as Matthias Reh refers to them. "We had only older machines that left us far removed from high-precision machining." That changed in 2015 when Reh decided to replace his ageing C 1200 U with a C 42 U from Maschinenfabrik Berthold Hermle AG.
"Of course we looked around at various manufacturers in advance. But what pointed clearly in the direction of Hermle was my experience and the Service Department," says Reh. He had already worked on machining centres of the machine builder with headquarters in Gosheim, Germany during his apprenticeship, and he had to call the service technician more and more often for the C 1200 U he had acquired. "The dedication and availability for service calls were always top-rate, even though the machine was already almost 20 years old. It was an easy decision for us to make." The discussions with the bank were not so easy: "For us as a small business it was a very large investment. And the fact that we had only been on the market for two years was another cause for concern for the bank," adds Reh. It was a discussion he would not have to go through again in the future – not even the company founder had foreseen what a turnaround the new 5-axis machining centre would bring. The ability to mill different materials into elaborate shapes changed both our range of parts and our customer base. "The machine arrived in November 2015, and over Christmas we already manufactured the first complex tool carriers for the food industry," remembers Reh. "So I was in the high-end sector."
The requirements were fundamentally different from the simple beginning parts: To be able to use machines for food processing, they must meet the highest hygienic standards. Therefore the individual components must not have any grooves, sharp corners or hidden edges after machining. They are mostly made of austenitic stainless steel type 1.4301. This material, also called VA steel, is easy to clean but has high requirements for the milling process. "It is especially tough and warps very quickly due to stresses in the raw material," explains Matthias Reh. "If a lot of material has to be removed on one side, for example, the right expertise is needed to succeed in counteracting the warping that is caused by stresses to have an even part in the end."
In the two years that followed, Der Span increasingly established itself as a supplier of machine components for batch sizes 1 and up for the food industry, also quickly reaching the limits of its capacity.
Getting started with automation
Matthias Reh expanded his machine park in April 2017, adding a C 400 U with HS flex system. "We were looking specifically for a system with automation because the workpieces we had to manufacture had very long runtimes." The Hermle handling system was impressive with its intuitive usage and logic. Two storage modules with space for six large pallets 500 x 400 millimetres and nine pallets 400 x 400 millimetres ensure sufficient buffer and allow for set-up in parallel to machining time.
And what did the bank have to say about the new investment after just two years? "The C 42 U had boosted our sales so much that the bank had no more objections for the C 400 U," grins Reh. The machining centre purchased in 2017 is now working at 100% capacity: Rough machining is performed during the supervised shift, since it can only be carried out under supervision. Finishing is then carried out overnight or on the weekend. "This fine machining alone lasted ten to 14 hours for each workpiece. So we were searching specifically for a reliable automation solution," explains Matthias Reh. His expectations have been fully met, confirms Reh, who calls the 5-axis machine the workhorse of the company.
HIMS, the central monitoring tool, gives him the assurance that the process is running smoothly. In addition to the live status and a detailed evaluation of the status history, the software messages him by e-mail if an error or unexpected event occurs. Summing it all up, he adds, "The machine is productive and I have my weekend free."
Concept of rotational machining alone has had its day
Although the addition of an automation solution represented remarkable growth, there is still more to the story. When Matthias Reh wanted to replace an old turning machine that dated back to the company's founding, he contacted Hermle directly. "Often our turned parts still had to go on the milling machines because there was still a bore hole to drill or a groove missing. That made it clear to us that we needed a machine that could do both, he explains. So he focussed on the machining centres of the High Performance Line with Mill-Turn functionality (MT). There was very little time between the initial contact and the sales contract: At the beginning of 2019 he received an offer to purchase a demonstration machine type C 42 U MT after the in-house exhibition two weeks later. "We settled financing issues with the bank, had another up-close examination of the milling-turning centre at the in-house exhibition in Gosheim and signed the contract. It went so quickly that we had no time to think about possible alternatives," remembers Matthias Reh. He never regretted it.
With the new manufacturing capabilities came new customer in medical technology and the energy sector. The challenge this brings with it is the diversity of materials. For example, Reh and his team machine both cast steel and titanium on the C 42 U MT. The shapes of the valves and other features are often similar or even identical. Only the material is adapted for the intended purpose. The geometries are less problematic: "There is actually nothing complex on the Hermle machine if you have the right machining strategy in mind," notes the industrial mechanic.
But it is not quite as simple as that. "In the beginning I underestimated the technology. For example, it is very important how the component is clamped. Otherwise dangerous imbalances will develop during rotational machining." Reh cites this as the cause of an extra two or three weeks in the introduction phase compared to simple milling centres . "Now it runs just as reliably and stably as the other machines."
Although the milling/turning centre has only been in use at Der Span since September 2019, the investment has paid off for the young company. "The fact that we are manufacturing on Hermle machines often eliminates the question of whether we are up to accepting an order in terms of quality," reports Reh, who seems almost a little surprised that Hermle is a solid selling point.
The three machines from Gosheim are all working at full capacity. Of course productivity has risen, although this must be understood in a nuanced context: "We started with antique systems," says Reh, putting matters in perspective while drawing an overall positive conclusion: "I have never regretted buying Hermle machines. Along with the quality and precision, we were impressed from the very beginning by the Service Department, which had a solution on hand for every problem." It hasn't even been two years yet – who knows where this will lead in the future? "Of course we are aiming for further growth. When the next investment will come is not clear yet at the moment. But there is no question that it will come," promises Matthias Reh.