Machining Equipment Mold making: Complete machining in one set-up
Formenbau Niemann in Gemünden am Main, Germany chose DMG Mori’s DMU 75 monoblock with a PH 150 pallet changer to machine aluminium 4-cavity molds for the creation of a unique, soft, skin-friendly and reusable mouth-nose mask called ‘Covi-Mask’ in the background of the Covid-19 pandemic.
One of the measures to combat the Covid-19 virus is wearing mouth-nose masks. Even though experts had strongly debated their effectiveness at the beginning, it was foreseeable that they would soon become part of everyday life. Looking at the range of masks, Thomas Niemann, the owner and managing director of Formenbau Niemann, noticed that many models only provide protection for a very limited period of time: “After that, they end up in the trash as disposable items.” So, at the end of March 2020, he says, the idea was born to develop a reusable mask made of plastic.
4-5 weeks of tinkering with different prototypes
The company focuses on casting molds made of aluminium for prototypes, molds for small to medium production runs, all the way to fully automated molds made of steel for large-scale production. It caters to customers from the medical technology, automotive and aerospace industries for the design and manufacture of complex components.
This experience and, above all, the know-how in design helped Thomas Niemann to develop a mouth-nose mask that met his expectations within a few weeks. “With each new prototype, we were able to further optimise the mask,” he recalls. “After four or five weeks of work, we had the desired result: a comfortable-fitting mask made of soft plastic with a replaceable filter element.” The filter currently in use is a FFP3 fleece made in Germany.
Optimising manufacturing processes
For Formenbau Niemann, manufacturing the tools for the various prototypes is both daily business and core competence. This also explains the use of state-of-the-art manufacturing technology. For 21 years, the company has been working with machining centers from DMG Mori. In 2013, a DMU 85 monoblock was installed, which can accommodate molds up to 935 x 850 x 650 mm. This was followed in 2019 by the DMU 75 monoblock with PH 150 pallet changer. “On this machine, we machined the molds for the masks.” This also includes the 4-cavity tool for the mouth-nose mask that is now available, he said.
In order to cope with rising quality demands and increasing competitive pressure, the firm began very early on to optimise manufacturing processes in the long term – initially with 5-axis simultaneous machining. “Complete machining in one set-up enabled us to maintain our productivity and serve increasing accuracy requirements,” says Thomas Niemann, looking back on the development.
Complete machining in one set-up enabled us to maintain our productivity and serve increasing accuracy requirements.
Potential crashes can be prevented in advance
Complete machining and the recently installed PH 150 pallet handling system have changed the processes at the company significantly. Whereas two employees used to spend a week working on a complete mold, today one employee can do it in two days. “The second employee now ensures that the ten pallets are prepared at an additional programming station,” explains Thomas Niemann. In this way, the team can utilise the DMU 75 monoblock in two additional unmanned shifts.
With such long unmanned times, it is all the more important that the machine runs reliably. “We ensure this internally with program simulations in an exact 3D model of the workspace,” says Tim Niemann, son of the managing director. In this way, he says, potential crashes can be prevented in advance. In addition, DMG Mori's service plays a major role, because unscheduled machine downtime has a serious impact on productivity in automated production.
Mouth-to-nose masks post Covid-19
Thomas Niemann is glad that his company has weathered the Corona crisis well so far. Orders have not disappeared. But he would also like to push the mouth-nose mask as another mainstay. “We are still convinced of the quality and see it as a good alternative in many occupational groups that work with protective masks, even after Corona." Feedback from previous users, including a pulmonologist and a dental laboratory, has been consistently positive, he says: “The main arguments for our customers are the comfortable fit and the possibility of cleaning and disinfection.” Another advantage: no fogging of lenses, as is known from surgical or fabric masks. The production capacities are large enough: “We can produce up to 10,000 pieces a day.”