HIGH OUTPUT IN A COMPACT SPACE.

Gemü Gebr. Müller Apparatebau GmbH & Co. KG | ACURA 65
Field of application: Tool and mould making | Company headquarters: Ingelfingen-Criesbach, Germany | Employees: 21

Source: www.werkzeug-formenbau.de

The family-owned company was founded in 1964 and is a leading manufacturer of valves, measuring and control systems for liquids, vapours and gases. Gemü is the world market leader in solutions for sterile processes. The group currently employs more than 1900 people worldwide, including around 1100 in Germany. At the toolmaking site in Ingelfingen-Criesbach, 21 employees manufacture tools for technical plastic parts, especially for floor and high-temperature plastics, on a production area of 750 m² for plant engineering. However, the production of injection moulding tools with interchangeable inserts of up to 28 variants is also a speciality. The toolmakers in Ingelfingen have their own technical centre with 14 injection moulding machines with clamping forces of up to 400 tonnes.

The toolmakers at Gemü rely on the ACURA 65 EL from HEDELIUS for the pre-milling of their tool components. The universal milling machine performs with a robust travelling column construction on a very small footprint. Thanks to the large tool store, automated production also brings great advantages.

The toolmakers at Gemü in Ingelfingen did not make it easy for themselves when it came to purchasing a replacement for their ageing 5-axis milling machine. The new machining centre had to be well equipped, automated and optimally accessible, but at the same time space-saving, not exceed a certain ceiling height and also have a high level of stability and precision. Doesn't sound particularly demanding in theory. However, as it turned out in practice, not many machine manufacturers were able to cover this performance spectrum.

Ralf Herrmann, Head of Tool Technology at Gemü, explains: "Our tool shop is located on the first floor. Our ceiling height there is limited to three metres, which is why we always have to consider the weight and height of the machine when purchasing a new one. The previous model was technically completely outdated. The accuracy was also no longer sufficient. We wanted to invest in a new machine that would offer us greater travel paths and more cutting capacity on the same footprint."

The toolmakers at Gemü specialise in moulds for technical plastic parts for plant engineering, especially for fluoroplastics and high-temperature plastics.

The experts primarily develop and manufacture tools for the Gemü Group's own production facilities. However, if capacity utilisation allows, they also produce tools for external customers. Typically, these are injection moulding tools measuring up to 696 x 696 mm and weighing up to 1.5 tonnes. However, 2K injection moulding tools with rotary plates or transfer technology, tools with interchangeable inserts of up to 28 variants or vulcanisation tools are also part of the core business.

Uninterrupted cut.

Thread demoulding is an everyday task for the plastics specialists, as is the interrupted cut process. "This process is very demanding and stressful for the milling centre. Drilling into a stainless steel body with an interrupted cut is a recurring application for us. The larger the drill bit, the more cutting forces and vibrations are generated. We need an extremely stable machine design here," explains Herrmann. "We designed our acceptance part according to these criteria and wanted to test the durability and precision of the machine. In doing so, we realised that many manufacturers have reached their limits."

The ACURA 65 EL universal machining centre (machining centre for short) from HEDELIUS ultimately came out on top in the benchmark test conducted by the plastics experts from Ingelfingen. Much to the surprise of the toolmaking team, who had no previous experience with the machine manufacturer from Lower Saxony. One of the machine operators became aware of the ACURA 65 EL at the EMO in Hanover in 2017 and brought it into play at the benchmark. "It's always important to me to involve the employees when making decisions," emphasises Herrmann.

Thanks to the travelling column construction, the 5-axis machining centre guarantees the required stability, for example for drilling in interrupted cuts, and offers travel paths of 700 x 650 x 600 mm (X, Y, Z). Herrmann: "This is unbeatable on the required footprint of 3900 x 3700 mm and with the machine's low overall height of 2500 mm and, for me, an absolutely unique selling point."

The toolmakers are equally enthusiastic about the standby magazine, which provides additional space for 180 milling tools and is directly adjacent to the rear of the machine. In addition to the 65 tools from the main magazine of the machine, the experts now have a total of 245 tool spaces available for production.

Herrmann: "Since we decided in favour of the ACURA automation package (EL), such an additional magazine is simply a must for us. HEDELIUS has released this ingeniously with its in-house development. We haven't found anything this compact from any other supplier."

Gemü's standby tool storage also includes a cone cleaning station for the HSK-A63 tool fittings. Depending on requirements, the machine operator can initiate the cleaning process for a specific milling tool or all tools.

In the cleaning station, the milling tools are automatically cleaned with a rotating brush before corrosion protection is applied. Herrmann: "Especially in the unmanned milling process, it is important that the short taper holder is clean and free of chips so that concentricity and positioning accuracy can be ensured later in the machining process."

The ACURA 65 EL can be automated from the left-hand side of the machine using a pallet handling system or a robot, regardless of the manufacturer. This means that the door of the 5-axis machining centre remains fully accessible for the manual production of single parts, which was also a decision criterion for Gemü, as Herrmann reports: "In day-to-day operations, we have programs that only run for a few minutes. For this, the machine must be optimally accessible despite the automation."

HEDELIUS leaves the choice of automation partner up to the user, but is unable to offer a turnkey solution due to the large number of suppliers. The specialists at Gemü opted for a 6-fold Erowa Robot Easy pallet changer, with which they can lift pallet weights of up to 250 kg.

"We wanted to get the most out of the automation. Erowa is a good partner for us, and the output of the Robot Easy with the high payload and the larger MTS-400 pallet system was convincing," explains Herrmann.

Logistical masterpiece.

The workpiece loader from Erowa was delivered at the same time as the machining centre. "This is always spectacular for us, as we have to use a 120-tonne crane to transport all the parts to the first floor and remove them. However, this went smoothly and commissioning took no longer than three weeks."

At Gemü, the ACURA 65 EL is used for pre-milling mould plates, inserts, slides or cores, among other things, but also for finished mould plates. The experts very often rely on stainless steels for the production of their parts, which weigh a maximum of 90 kg.

In Ingelfingen, mould making is not just mould making, but also an extended workbench for the Gemü Group. Herrmann: "As a service provider for the group of companies, we are always commissioned when something is very complex or needs to be done quickly and with particular precision." For the production of a valve body made of Teflon, for example, the toolmakers designed and completed a flow-optimised mould made of chromium-nickel steel with two variants.

Working with PFA high-performance plastics requires a high level of expertise from mould makers. Thanks to the new machining centre, however, some production steps have become easier.

Herrmann: "We only had 30 milling tool positions available on our old 5-axis milling machine. In the past, we couldn't even run long-linked programs because there weren't enough magazine slots. In addition, the system often came to a standstill during set-up. Thanks to HEDELIUS, we are now able to save up to 50 per cent of tooling times, depending on the application. We have become significantly more efficient."

The toolmakers have been using the machining centre since January 2019. Herrmann: "When we need the service, we get support and are not just a number. We are well looked after here, and we have already used the HEDELIUS service app twice." With this app, users can make service, inspection or spare parts requests quickly and easily directly at the machine.

Convincing overall package.

"HEDELIUS was an unknown supplier for us, so we were very sceptical at first. Even though the facts and figures spoke for themselves, it was ultimately the visit to the demonstration centre in Meppen, 550 km away, that won us over," says Herrmann. "The ACURA 65 EL was originally above our budget. However, the seal of quality 'made in Germany', the key figures and the great benefits compared to competitor machines justified the investment for us."

SOURCE: www.werkzeug-formenbau.de