Masking-free painting of refrigeration unit glass surfaces without overspray

Glass surfaces of refrigeration units are painted with Dürr's EcoPaintJet paint applicator without masking or overspray. This is the first time that overspray-free paint application has been used in other branches of industry.

With the EcoPaintJet, overspray-free paint application has found its way into industrial vehicle painting. Now other branches of industry are also benefiting from this solution. In the Refrigeration division, PAN-DUR manufactures insulating glazing for commercial refrigeration units. For some months now, the glass surfaces have been processed with Dürr's innovative applicator. This saves time and material, as individual screens no longer have to be produced for the screen printing process.

Everyone knows them from the supermarkets: The large-volume refrigeration units, be they wall shelves, cabinets or counters, behind whose glass or plastic panes a wide variety of foods are stored. PAN-DUR manufactures its glass elements from safety glass (ESG). Opaque decorative strips are applied to conceal the unsightly adhesive and sealing seams on the edges of the glass and the refrigeration technology behind it. Previously, PAN-DUR used the screen printing process for this. The disadvantage: a new screen or stencil is required each time the color, size or design varies.

With the EcoPaintJet, PAN-DUR saves itself this time-consuming process, gains flexibility and speed in production and reduces paint costs. This is because the EcoPaintJet paints with sharp edges and without any overspray. Each contour is simply programmed and applied in the desired color to the corresponding predefined surface - without masking the glass surfaces beforehand. This also eliminates the time-consuming and costly production of individual stencils and their space-intensive storage.

Dürr not only supplied the applicator for the paint application, but also provided PAN-DUR with the entire process technology, from paint removal to paint supply. The components installed include the Fluid Board paint metering and color change system, the cleaner unit for the applicator and the EcoAUC control unit. For the seamless integration of the process technology, PAN-DUR developed a multi-axis gantry on which the EcoPaintJet's rotatable and height-adjustable application head was mounted. "We linked the Dürr process technology with the interfaces of our system. The implementation went completely smoothly," explains Jens Verhoef, Development Manager for Electrical and Automation Technology at PAN-DUR.

The biggest challenge proved to be finding the right paint for use on glass surfaces. A long-standing partner of PAN-DUR, the paint specialist Votteler, was also involved in the development. Project manager Uwe Schmidt explains: "Painting glass surfaces is very demanding. This requires specially developed paints that are perfectly matched to the system in terms of their rheology, opacity and particle distribution. This coating system can also be used on other substrates. That's why it took a few test rounds before we found the right coating."

Other industrial applications are also conceivable for the EcoPaintJet, for example in the wood industry, in window or kitchen construction, but also in the field of painting rail vehicles. "There is potential wherever straight stripes need to be applied to a flat surface and where masking is still used during painting. There are a number of inquiries from different industries," says Fabian Schilt, head of the European industrial sales team at Dürr. An additional advantage that makes the overall system attractive for other applications is that all components are "ready-to-integrate", i.e. easy to integrate into existing production systems. (OM-7/24)