Maximum corrosion protection plays a central role in the longevity of truck trailers and semi-trailers. In order to be able to produce them economically despite high requirements, the Lower Saxony company System Trailers relies on a high degree of automation and optimised manufacturing processes. After powder coating by an external job coater had become a bottleneck in production, managing director Ralf Saatkamp solved the situation consistently and founded Giga Coating in autumn 2015 as his own coating company for large-format components in automotive quality. A hall of approximately 8600 m2 was built on the company's premises, in which very large and very heavy workpieces are made corrosion-resistant by means of cathodic dip painting and powder coating. Since the opening of the new plant in 2018, a sophisticated conveyor system has been moving the workpieces, which can be up to 16 metres long and weigh up to 9 tonnes, through the 11-stage pre-treatment of blasting, degreasing, zinc phosphatisation and cathodic dip painting before they reach one of the two custom-built quick colour change booths (ColorMaxE) from Nordson. This was followed in 2020 by the installation of the second powder coating system. Due to their compact design, the booths are developed for particularly fast, largely automated cleaning processes to minimise lengthy production interruptions during the multiple colour changes per shift.
In the booths, a total of 22 automatic powder guns (Encore HD) each efficiently ensure very uniform powder application with maximum process control over a long period of time. In the spray system with HDLV pumps, more powder is pumped to the powder gun at low speed and using less air. The resulting "soft cloud" produces excellent first coat efficiency and allows maximum process control. For coating very special moulds, two additional manual coating guns each are available. The manual coating stations are equipped with lifting platforms for better accessibility of the component, which can be up to 2.7 metres high.
95 percent degree of automation
The first booth without Dynamic Contouring requires a little more recoating than the latest booth with Dynamic Contouring System. This results in even more precise control of the powder guns - without programming. Scanners in the entry area of the booth recognise the geometry of the incoming workpiece. These pass the data on to the DCM system via the control system in order to bring the powder guns to the optimum distance from the workpiece. The result is an even more uniform coating of the complex geometries, even lower powder consumption, fewer re-coatings and higher productivity. The system thus operates up to 95 % automatically.
The complete article was published in IST 04/2020.
Author(s): Nordson Deutschland GmbH, Giga Coating GmbH