in Vol. 19 - January Issue - Year 2018
Successful Implementation Of Aluminum Wheel Painting Lines For Swiss Ronal Group
High-speed rotating atomizers ensure reduced overspray during final clear coating
Specially designed self-adjustable spindles adapt automatically to different rim types and bolt circles
Ronal also produces rims in sophisticated design, as shown here in black and red
The Dürr Group has had a direct representation in Italy for many decades and currently employs around 260 staff there. The national companies in Italy offer the Group's entire portfolio: Olpidürr S.p.A. (Novegro di Segrate) operates in the fields of paint shops, exhaust-air purification systems and energy efficiency technology, while Verind S.p.A. (Rodano) specializes in paint application technology. The final assembly and conveyor systems business falls within the remit of CPM S.p.A. (Beinasco). Schenck Italia s.r.l. (Paderno Dugnano) is responsible for balancing technology. The HOMAG Group is represented in Italy through Giussano-based sales and service company HOMAG Italia. The Dürr Group is one of the world's leading mechanical and plant engineering firms with extensive automation expertise. Products, systems and services offered by the Group enable highly efficient manufacturing processes in different industries. Dürr supplies sectors like the automotive industry, the mechanical engineering, chemical and pharmaceutical industries, and the woodworking industry. The company has 86 business locations in 28 countries. The Group generated sales of € 3.57 billion in 2016. Dürr has around 14,500 employees and operates in the market with five divisions: Paint and Final Assembly Systems: paint shops and final assembly systems for the automotive industry; Application Technology: robot technologies for the automated application of paint, sealants and adhesives; Clean Technology Systems: exhaust-air purification systems and energy efficiency technology; Measuring and Process Systems: balancing equipment as well as assembly, testing and filling technology; Woodworking Machinery and Systems: machinery and equipment for the woodworking industry
Aluminum wheel painting. As one of the world’s leading paint shop suppliers, many think that Dürr is focused only on painting vehicle bodies, such as passenger cars, vans, truck cabs or buses. However, Dürr offers a wide range of painting applications for non-automotive-goods, trains and also for plastic and wheel paint shops. For the Swiss multinational Ronal Group, one of the leading players in aluminum wheel production, Dürr has recently implemented modern wheel painting lines in Mexico and the Czech Republic.
Within the Dürr Group the Italian subsidiaries Olpidürr and Verind act as a center of excellence for aluminum wheel paint shops providing systems integration and high-end application equipment. Recently, they executed two projects for the wheel manufacturer Ronal’s production of diamond-cut wheels. High-sheen and front-polished, diamond-cut finished alloy wheels are very popular and demand a special process: First the alloy is varnished, and then they undergo the diamond-cut process where a diamond blade creates exceptional visual effects. Finally the wheel is treated a second time and clear coat is added to cover the cut surface. The conventional process is to send the wheel through the same line twice, which blocks capacity in the production process. So it is much more efficient to add a second line.
Dürr supplied such a paint line for the finishing of diamond-cut wheels in Ronal’s Querétaro Mexico facility. Dürr Mexico, also based in Querétaro, played an important role in the project, especially in terms of local supply and installation, and will be on site for future service assistance. Supported by the worldwide network of the Dürr Group – whose expertise includes dedicated and customized planning of all crafts and process interfaces as well as efficient project management – the Italian subsidiary Olpidürr oversaw the successful implementation: The paint line in Mexico was commissioned in 2016 with a capacity of 250 alloy rims per hour and led to another important job in Europe.
Along with this project Ronal partnered with Dürr for a new paint shop at their site in Jičín, Czech Republic. Here, Dürr was commissioned to implement two painting lines with a capacity of 500 and 300 wheels per hour. Dürr again employed the split-line design, as this configuration optimizes the production process by avoiding second runs on the same line. Both painting lines are completely housed, to avoid indoor pollution of the production process. This design was also used in the Mexico project. Olpidürr was acting as a systems integrator. Verind, was the paint application equipment specialist, contributing automatic wet paint application systems including the paint mix room as well as circulating and spray equipment. The range of supply included the EcoBell 2 SL Direct Charge atomizer, the automatic color changer EcoMCC3, gear dosing and supply pumps, and paint flow and backpressure regulators. The painting lines are capable of processing both solvent-borne and waterborne paints”, thus meeting state-of-the-art requirements requested by the customer.
In addition to leading edge technologies and devices for wheel painting lines the Dürr concept for the Ronal paint shops in Querétaro and Jičín contain a variety of unique solutions focusing on energy savings throughout the plant. One of them is a CO2 heat pump that reduces the consumption of both thermal and electrical power during operation. Furthermore, the wheel transfer between synchronized conveyors and the process downstream is performed by manipulators: robots or cranes fitted with superlight grippers were specially designed for the wheel transfer between synchronized conveyors. Other developments included self-adjustable spindles and self-aligning jigs as well as a brushless powder removal system for the wheel hub and mounting face.
Emissions of volatile organic compounds (VOC) were minimized by a regenerative thermal oxidizer (Dürr RTO 3035). With Dürr RTO 3035 customized for wheel-painting related exhaust air, the condensation of high boiling solvents in the oven’s exhaust air (which are typical for aluminum wheel wet paints) is avoided.
To keep the production process running smoothly, in-house team of Dürr IT specialists developed supervision software for Ronal. Its use makes the production process extremely safe, manageable and allows for remote troubleshooting and modifications during the entire life-cycle of the paint line.
The start of installation in Jičín was in January 2017 and SOP has taken place in October 2017.