Additive manufacturing with metal in particular involves risks, as the fine metal powders can be harmful to health and can form explosive atmospheres when whirled up. Due to the laser melting process, the workpiece is still in a dense powder cake after completion of the construction process, which leaves residues in the support structures and internal contours of the component. This residual powder in particular can lead to considerable difficulties and time losses in subsequent processes. Unpacking from the residual material is difficult due to the fine powder residues from production. "Until two years ago, little attention was paid to the post-processing of metal prints," explains Andreas Hartmann, Managing Director of Solukon Maschinenbau. In addition to the health risks, explosive atmospheres can also occur when the finest particle materials, such as aluminum or titanium, are whirled up. A German car manufacturer approached the machine manufacturer with this problem. "Our solution was a safe cleaning cabin with an automated cleaning process," explains Hartmann. "One of the challenges was to develop an efficient and ignition source-free cleaning device within a process chamber flooded with inert gas." The process chamber, which includes a spatial swivel device, removes metal residues automatically and almost completely in a closed circuit.

The relevance of the pneumatic valve

Images

Workpieces produced using the laser melting process still have powder residues adhering to them, which are removed in the process chamber of the cleaning cabin. This component was designed by Airbus Operations and manufactured by Robert Hofmann. (Image: Aventics)

To rule out any risk of explosion, the process chamber must be safely flooded with inert gas and constructed without ignition sources. An essential part of the fully automated cleaning booth is therefore the use of pneumatic components. Drives controlled by compressed air are the only way to design a machine that is both efficient and hazard-free. The AV series valve systems are used to control the pneumatic components. This also allows the division into compressed air and protective gas control to be easily implemented. The pneumatic cylinder from the CCL series is particularly suitable for use in the process chamber, as it is intended for use in potentially explosive atmospheres. The smooth surface of the CCL also facilitates the cleaning process of the cabin.

"The challenge with the Solukon cleaning cabin was to develop a technology that had to meet various requirements," comments Michael Lehner, long-standing sales partner of Aventics. "It was therefore particularly important that we were involved in the design right from the start."

This case shows that the areas of additive manufacturing also develop best when the processes are viewed from a cross-company perspective and the experience of various automation areas is incorporated. Hartmann also confirms that innovations developed in this way offer added value for the entire industry: "Thanks to the good cooperation, we were able to find a convincing system solution quickly and easily, which also benefits our customers in additive manufacturing." ee