Compact painting robot for industry

(April 2020/OM) - When it came to developing new specialty coatings, WB Coatings had reached its limits with the hand application method it had used until now. That's why the globally active paint and coatings manufacturer came up with an idea that is unusual in its industry: it is equipping its research laboratory with a compact painting robot from Dürr.

The use of the painting robot enables absolutely reproducible coating thicknesses in the µ range, which are absolutely necessary, for example, to develop chrome imitating paint systems. The pre-installed, ready-to-paint robot from Dürr is a professional solution for automated paint application. With coordinated and proven components, it is fully tailored to the requirements of the general industry and in this combination is unique on the market. WB Coatings is the first paint manufacturer to now develop its new products with the "ready2spray" robot.

For more than 135 years, WB Coatings has been known for its innovations, not only as the inventor of the hammer finish, but also of many other specialty coatings. Research and development are still intensively pursued today. In the company's own laboratory, formulations for the classic industrial coatings sector are continuously optimized, while the Innovation Center focuses on new developments for diverse industries.

One product innovation, for example, is a chrome-effect paint that is used for vehicle interiors, among other things. This gives plastic components, such as window regulators or decorative clips in the steering wheel, a deceptively genuine chrome look. WB Coatings achieves this effect with paint systems consisting of one, two or three paint layers. "Without the use of a robot, it would not have been possible for us to develop these novel paint systems as a chrome-free alternative for silvery surfaces at all. The challenge was to apply the paint layers of the chrome-effect paint very evenly. And especially with the three-coat paint system, particularly thin, reproducible layers of 2 to 3 µm are to be painted. Even very experienced hand painters can't manage that," explains Andreas Ohletz, Sales Manager Innovation at WB Coatings.

To meet this requirement, WB Coatings opted for an automated painting solution from Dürr. This consists of the six-axis EcoRP 10 R1100 small robot with state-of-the-art application technology including mixing and metering technology for two-component paints (2K), paint supplies and control.

The automated spraying program of the robot system does not allow any deviation and thus achieves maximum repeatability. This starts with dosing the components in exactly the same ratio every time. If, on the other hand, the smallest quantities of just a few milligrams are mixed by hand, the risk of inaccuracies is great. The coating result is also influenced by the application speed and the distance to the object to be coated. These factors naturally fluctuate during manual application, whereas the robot works completely uniformly and thus always produces identical coating thicknesses. "A major advantage for us is the in-house trials we can now run in our pilot plant with different basecoats to test formulations. Thanks to the robot, we are able to replicate automated production in industry and develop new coating systems with which our customers can produce economically in series production," says Sebastian Grahammer, head of development at WB Coatings' Innovation Center.

Normally, only sample sheets and paint frogs are coated in the paint manufacturers' laboratories. The surface spraying system originally envisaged by WB Coatings would have sufficed for this. But by opting for the six-axis robot, the coatings manufacturer remains flexible for customer requirements in the future, Sebastian Grahammer is convinced: "The robot enables us to coat three-dimensional objects with complex geometries. With a two-dimensional spraying system, we would have limited ourselves in our own development possibilities."

As the application technology is already pre-installed, the Dürr robot system was set up, installed and ready for painting at WB Coatings in just one and a half days. Thanks to its compact dimensions, it could be integrated into the existing paint booth despite limited space. When the robot is in the parking position, painting can continue to be done by hand in front of the same suction wall.

"The painting robot is part of our ready2integrate concept. At the core of this concept are technologically mature and proven application solutions that can be easily integrated into individually designed systems. Here, Dürr works with selected system partners because they are very close to their customers, know their requirements and can act extremely flexibly," explains Holger Beiersdorfer, Vice President Industrial Products at Dürr.

Dürr Systems AG
www.durr.com