It’s round, a little twisted in some places, looks like it grew organically instead of being planted and built – and it is still incomplete. Sagrada Família in Barcelona is one of the most significant examples of architecture of Antoní Gaudí – and a true nightmare for architects. But additive manufacturing has simplified realization significantly, making the production of complicated components easier, or even possible at all. To transform Gaudí’s visions into a reality, architects are examining and analyzing the drafted design using 3D models, encouraging the completion of the building.
Additive manufacturing technology has long established itself in industrial applications. Besides unique design freedom for complex components, more efficient use of materials also plays a crucial role. Despite all advantages, metal printing is also entails risks, as fine metal powders can be harmful and when stirred up, they can sometimes even form an explosive atmosphere. Following the construction process, often large amounts of powder remain in the support structures and interior contours in the component and are very difficult to remove. These residual powders especially can cause significant difficulties and waste time in follow-up processes.
As a German automobile manufacturer approached Augsburgbased machine manufacturer Solukon with the problem two years ago, a timely solution was imperative. “Until then, postprocessing of metal prints had been given little consideration,” explains Andreas Hartmann, CEO of Solukon Maschinenbau GmbH. “Our solution was to develop a reliable cleaning booth with an automatic cleaning process. One of the challenges was developing an efficient cleaning device free of ignition sources within a process chamber filled with inert gas. Mainly pneumatic components are used to manage this demanding task. While selecting components, we relied on the expert consultation of our reliable AVENTICS partner, Michael Lehner Fluidtechnik, right from the start,” Hartmann continues. “Quick availability of information and samples, combined with the comprehensive AVENTICS product range, really helped us in developing our system.”
Layered application of material in 3D printing enables the fluid production of components in a single piece. Even components with complex geometries that would be impossible to produce using conventional means can be manufactured relatively easily. Additive manufacturing also gives efficiency a significant boost in terms of material use, but the process is also accompanied by challenges.
Production laser melting technique leaves the completed workpiece coated in a thick powder cake. The excess fine powder makes unpacking it from the materials left from production quite difficult. Beside the health risks, stirring ultra-fine particle materials made of aluminum or titanium for example can form explosive atmospheres. To make postprocessing safe, two years ago machine manufacturer Solukon developed a cleaning booth that was then unique to the market. The process chamber with integrated three-dimensional swivel device automatically removes virtually all metal residues in a closed circuit.
The SFM02-AT800 cleaning booth makes it possible to safely and efficiently clean metal components with dimensions of up to 800 x 400 x 500 mm (X/Y/Z incl. build platform). Cleaning is performed within a sealed process chamber flooded with inert gas. In this chamber, the component is swiveled in three dimensions and stimulated with targeted vibrations so that the powder residues come free and gather at the bottom of the chamber. The powder residues are then removed via a funnel. A 3D swivel device continually moves the components including build platform around two axes. Even complex cavities, indentations, and supporting structures can be freed completely from the loose building material. The gentle cleaning process in an inert gas atmosphere prevents explosive atmospheres from forming, also protecting the construction material against oxidation. One clear advantage of these automated processes lies in the many hours of postprocessing saved. Customers in the aviation and aeronautics industries are especially pleased with this new reproducible possibility to clean complex internal structures.
To prevent any risk of explosion, the process chamber has to be securely flooded with inert gas and totally free of ignition sources. Pneumatic components play a major role in the fully automated cleaning booth. Actuators controlled by compressed air offer the only option to design an efficient and risk-free machine. AV series valve systems are used to control the pneumatic components, meaning the block can easily be split into compressed air and inert gas control. The CCL series pneumatic cylinder is ideal for the process chamber, as it is intended for use in explosive areas. The smooth surface of the CCL also makes cleaning the booth a breeze. “With the Solukon cleaning booth, the challenge was to develop a technology that could meet a wide range of requirements,” comments Michael Lehner, longstanding sales partner of AVENTICS. “This is why it was really important to be involved in the design process right from the beginning.” This case shows how areas of additive manufacturing are best advanced by observing processes across companies and incorporating experiences from different areas of automation. Andreas Hartmann confirms that innovations developed in this way offer added value to the entire industry, stating, “thanks to the excellent collaboration, we quickly and easily found a convincing system solution that also benefits our customers in additive manufacturing.”