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New Painting Technology: Not Just for Car Bodies Anymore Coating equipment saves energy and space, thanks to air recirculation. A t Volkswagen AG���s assembly plant in Wolfsburg, Germany, it isn���t just the car bodies that the auto manufacturer is paying special attention to when it comes to paint coatings. The fully automatic paint shop for plastic parts uses mainly water-based paints and an environmentally friendly process to coat bumpers, fuel tank covers and small parts for the new Golf. And Volkswagen���s production line is aligned to the requirements of small-parts painting in terms of 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 basecoat, water-based paints are used, while the clearcoat area uses a two-component solvent-based paint. Paint application is carried out by 24 EcoRP L033 robots from D��rr. Through the application of flame treatment and a new treatment plant that replaced a common chemical system, plastic parts can be optimally prepared for painting by cleaning and activating the surface for paint adhesion. As a result, the use of chemicals and water can be completely dispensed with, eliminating the risk of residual water on the part to be painted and reducing 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. The EcoLCC2 linear color changer helps minimize color loss per color change and optimize transfer efficiency during painting. The line also includes an EcoDryScrubber for dry separation of overspray. This technology saves energy in the paint booth by recirculating air, and the dehumidifying oven adds to the energy savings by drying with cold, dry air that better absorbs the moisture of the water-based paint. In this case, the oven is heated to only 40 to 50��C in contrast to the usual 80��C, eliminating the cooling zone downstream of the oven. In addition to saving energy, this saves space, shortening the line by 30 percent. n pretreatment and electrocoat is followed by a primer layer. After the primer layer is cured, a topcoat layer of basecoat and clearcoat is applied and cured. Because this process is both costly and timeconsuming, it has become a focus for streamlining. White says the next-generation B1:B2 technology works within BMW���s integrated paint process and enables the car manufacturer to reduce the number of steps nec- essary to paint a vehicle by moving the traditional primer application into the topcoat booth. ���This movement eliminates the dedicated primer booth and all related processing,��� he says. The B1 layer provides primer, filling, chip and durability benefits, while the B2 layer provides color and additional durability. Both layers are applied wet-on-wet and do not require baking or a heated dehydration process in between. A two-component, solvent-based paint system is used to paint bumpers. FAster PAinting Process Since implementing the coating process, BMW has reported energy savings of as much as 30 percent, a 43-percent drop in carbon-dioxide emissions, and a 7-percent decline in volatile organic compounds. The company also says the new process reduces the time it takes to paint a single car by about 15 minutes, which is substantial since the Spartanburg plant builds close to 1,000 cars a day. The plant, which opened pfonline.com 19