Additive Manufacturing Start to think additively!
With the initiative ‘think additively’, Bühler located in Uzwil wants to ensure a rapid utilization of additive manufacturing. The specialists provide counsel, manufacture machines and cover the entire process chain from material procurement to ready-to-install components.
Bühler from Uzwil, Germany, a global specialist in process engineering and automation, develops processes and technologies for the production of flour and animal feed, pasta and chocolate. The core technologies used in the processing of the raw materials are mechanical and thermal technologies, including conveying, cleaning, sorting, grinding, mixing and forming of cereals and other raw materials in order to produce high-quality foodstuffs and luxury food. Bühler also manufactures complex plants for the chemical and automotive industries. These plants are used for the die casting of metallic components, for the coating of surfaces and for the automation of complex manufacturing processes, such as for the die casting machines manufactured in Uzwil.
In-house Production Creates Added Value
The company has a high vertical manufacturing depth and therefore a broad base of added value. The specialists produce most of the machines and systems they use for their in-house developed manufacturing processes themselves. To this end, they have fully equipped workshops with all the tried and tested production processes and facilities. In order to remain competitive internationally, the designers and production engineers are constantly working on innovative processes and use the latest technologies. This applies, on the one hand, to the process engineering plants designed in-house and, on the other hand, to the processes used to manufacture the components. For the latter, the experts are increasingly focusing on additive manufacturing, often referred to as 3D printing.
Staying Innovative with 3D Printing
Andreas Schachtner, Head of Business Development & Services in the ML Division in Uzwil, explains: "3D printing has been used for many years, especially for the production of plastic parts. Currently, engineers are increasingly using this process for the production of metallic components.” The reason for this is the large number of recently introduced, innovative machines and processes, which allow for components to be made of different metals such as titanium, stainless steel and aluminium by means of 3D CAD data. For this purpose, the metals are applied as a thin layer of powder. This takes place in a process chamber on an adjustable worktop. A CNC-controlled laser beam then sinters some areas of the powder in each individual layer to generate the walls of the workpieces.
As Andreas Schachtner reports, numerous manufacturers already offer a wide range of different processes and systems which are now proving to be worthwhile and profitable not only for single pieces, but also for the production of medium and large series.
"The large variety of additive processes available today, makes it possible to design and manufacture parts that cannot be produced with conventional production methods or can only be manufactured at great expense," says Andreas Schachtner, mentioning nozzles and mold elements that have to be cooled or heated close to the edges as examples. In the case of such components, near-edge manufacturing usually significantly improves their efficiency and usability. The same applies to complex components that consist of a large number of individual parts. An integral design, such as the one made possible by 3D printing, accelerates and simplifies production considerably. In addition, it usually ensures a more reliable function, e. g. absolute tightness, as there are no assembly separation points. “Additive manufacturing is particularly useful when innovative 3D printing significantly improves the technical and economic benefits of a workpiece," emphasizes Andreas Schachtner.
He is convinced that Bühler's designers and developers must first of all really understand the characteristics and opportunities of additive manufacturing in order to use them effectively. This is why, he and Patrik Högger, Head of Development and Service, organized three in-house information events in conjunction with the ‘think additively’ initiative.
Specialist Trade as a Competent Partner
The implementation of this project was also supported by Wenk AG, Biel. Founded in 1963, the company trades in high-quality machine tools and is the sole representative of some machine tool manufacturers in Switzerland, for instance Mazak. Traditionally, the company’s main focus is on turning and milling machines, vertical and horizontal machining centers as well as on multi-functional and grinding machines. The trading company offers a highly qualified service, ranging from consulting to commissioning and after-sales services. The company has positioned itself as a trustworthy partner for Swiss industrial companies.
Together with other manufacturers, Wenk supported the event with the presentation of innovative machines. Trumpf, presented its 3D printing machine Truprint 1000, which uses a laser beam to sinter metal powder. The optimized handling of the fine dusty powder in a closed-circuit system is a specialty of this solution.
Application of Materials and Milling on One Machine
Mazak, the exclusive distributor of Wenk, introduced the Variaxis j-600 AM wire-arc coater, which is used to apply basic geometries with special component details. These include worn turbine and helical gears. In a rapid sequence, the machine welds the programmed geometries using a wire welding process and then processes them with the milling spindle (12,000, optionally 18,000 rpm speed) in five axes without the need for reclamping. As both build-up welding and 5-axis milling use the same 3D CAD data as a basis, the components are machined with high precision and are ready for installation. Another advantage is that by using a wire, high-quality, particularly wear-resistant or hard materials can be applied to base bodies made of lower-cost metals.
Matsuura showed a hybrid machine for laser application and immediate subsequent HSC processing of the applied and sintered layers. The advantage of this solution is that there is no need for time-consuming reworking to obtain high-quality, smooth surfaces of laser sintered components. This also applies to the interior of components that cannot be machined after completion. Therefore, this process is particularly suitable for nozzles and similar components that require smooth inner surfaces with good flow characteristics.
Alphacam Swiss presented its special software for 3D printing applications together with Stratasys 3D printers for the production of components using the FDM process. These systems can use thermoplastics to produce a wide range of workpieces.
The respective details, the special features and advantages of their processes and machines were explained by the manufacturers in brief presentations. More than 200 participants, mainly designers, production planners and employees from Bühler, followed these speeches closely. As Andreas Schachtner says, this contributes significantly to achieving a high level of acceptance of additive manufacturing in daily design and production practice. “Additive manufacturing has clear advantages if you know the process and its parameters. With our in-house exhibition and information event, we have taught our employees a wide variety of methods and applications in a very compact way. In order to take advantage of this in the future, especially with regard to innovative customer benefits and our own competitiveness, we have to learn to think in a much more ‘additive’ way. With our initiative, we have given a strong impetus to this," he concludes.
This article was first published by Schweizer Maschinenmarkt.