Durr painting technology: Not just for car bodies

Dürr is the general contractor for a fully automatic paint shop for plastic parts for Volkswagen AG in Wolfsburg. Volkswagen uses mainly water-based paints and an environmentally friendly process in this facility. Bumpers, fuel tank covers and small parts for the new Golf are to be painted.
The production line is aligned to the requirements of small parts painting. It includes cleaning and applying primer, the technology for base and clear coat application, as well as the oven and the workspace equipment. From the primer to the base coat, water-based paints are used, while the clear coat area uses a 2-component solvent-based paint.

Paint application is carried out by 24 EcoRP L033 robots. Through the application of SnowClean and flame treatment, plastic parts can be optimally prepared for painting, this means cleaning and activating the surface for paint adhesion. SnowClean in this case replaces the previously common chemical pre-treatment plant. As a result the use of chemicals and water can be completely dispensed with. This procedure eliminates the risk of residual water on the part to be painted and therefore reduces the quality risk for subsequent painting.

The primer application of 2K water-based paint is carried out by EcoBell3 atomizers in high rotation mode and without high voltage. In conjunction with the EcoLCC2 linear color changer, minimal color loss per color change and optimum transfer efficiency can be achieved during painting.

The EcoDryScrubber, the dry separation of overspray, is also included in this line. This technology saves energy in the paint booth through air recirculation. The dehumidifying oven produces an additional energy savings effect through drying with cold, dry air. This better absorbs the moisture of the water-based paint. In this case the oven is heated up to only 40 to 50°C in contrast to the usual 80°C. This eliminates the cooling zone downstream of the oven which, in addition to energy, also saves space as the line is shortened by 30%. Through the combination of SnowClean, EcoDryScrubber and dehumidifying drying, the painting of plastics is virtually free of process water. This is new and trendsetting for the painting of plastic parts.

The plastic component paint shop in Wolfsburg, commissioned by VW in the first quarter of 2012, will come into operation in August 2013.

Dürr is a mechanical and plant engineering group that holds leading positions in the world market in its areas of operation. It generates a good 80% of its sales in business with the automotive industry. It also supplies the aircraft, machinery, chemical, and pharmaceutical industries with innovative production and environmental technology. The Dürr Group operates in the market with four divisions. Paint and Assembly Systems plans and builds paintshops and final assembly systems for the automobile and aircraft industry. Application Technology provides automated paint application, sealing, and glueing with its robot technologies. Machinery and systems from the Measuring and Process Systems division are used in balancing and cleaning processes, in engine and transmission manufacturing and in final vehicle assembly, among other areas. The fourth division, Clean Technology Systems, is focused on processes to improve energy efficiency and on exhaust air purification. Dürr has 50 business locations in 23 countries worldwide and approximately 7,300 employees. The Group achieved sales of € 1.9 billion in 2011.