Wandel, which is based in the German town of Rottenburg am Neckar, began specializing in electrostatic powder coating around 40 years ago. In its 5000 square meter factory, it now employs 60 people who work in two shifts. The company also provides services such as the chemical pre-treatment of the components in preparation for power coating and the complex masking of parts. Its customers include international companies from the mechanical engineering, electrical appliance and automotive industries. The items that it coats range from flat metal parts to a variety of tubular and wire components. Initially Wandel used only manual powder coating systems, but its customers’ growing demands for improvements in the quality of the surfaces and the increasingly complexity of the parts led to the need for reliable coating machines that would allow the company to react flexibly to different types of customer orders. As a result, Wandel began investing in automated systems. Because of its positive experiences with Wagner spray guns and control units, Wandel chose Wagner to supply its automated powder coating systems. Wagner’s plastic Prima Cube and Super Cube spray booths have a PVC sandwich structure that keeps the build-up of powder to a minimum. In addition, a blow-off device integrated in the floor returns any overspray to the powder circuit and, together with the automated fresh powder supply system, ensures that the quality of the powder remains consistent.
Automatic gap, height and depth control
As in all of Wagner’s automatic booths, the extraction pipes fitted on both sides of the booth ensure that no disruptive airflows form in the coating zone. This stops the powder cloud from being sucked out from under the workpieces and prevents a reduction in the amount of powder being applied to the underside. Less manual reworking, more consistent coatings and a more efficient use of powder also help to increase productivity. The automatic system for controlling the gap, height and depth records the contours of the workpieces and adjusts the gun distances to the ideal settings. The automated guns produce a homogeneous powder cloud and charge the powder electrostatically to achieve a high level of application efficiency. At the same time, the extraction of the overspray on both sides of the booth keeps material consumption to a minimum.
The complete article was published in IST 02/2021.
Author(s): Michael Topp (J. Wagner GmbH) and Heiko Wandel (Wandel GmbH – Powder coatings)