This year, Heraeus Noblelight was asked by the House of Technology (Haus der Technik e. V.), for the seventh time, to organise the seminar on infrared heating, with a similar seminar to take place next year. The seminar is directed at system planners, technicians, engineers and users from all sectors that use heating processes in their industrial manufacturing processes. Based on examples of processes from plastics processing to drying lacquers, different presenters allowed seminar participants to share this practical experience.
Infrared heating technology has long had a role in industrial processing – there are hardly any products now that are not exposed to infrared heat during the production process. Infrared heaters can be adapted to products and processes, in terms of performance, form and spectrum. It is therefore worth getting to know the basics, opportunities and risks, to be able to choose the right infrared heater for your purposes. The seminar at the House of Technology in Essen, as well as presenting the basics of infrared heating technology, also offered a close look at application examples.
Dr. Rainer Sälker of Brillux GmbH presented an installation that coats polypropylene panels using flaming and spray painting, resulting in a natural stone or clinker appearance. A Russian manufacturer of plastic facade components produces PP-Panels with an injection-moulding process and coats them with an eco-friendly 2K water-based lacquer. These panels are used in Russia to clad public buildings and private houses, and need to be weatherproof. A particular challenge was a shortage of space on the production floor at the site where the coating installation needed to be integrated. The speedy transmission of large amounts of energy through infrared rays made it possible to create enough space. For drying, carbon infrared radiators were chosen, as this water-based system can dry extremely efficiently. Carbon infrared radiators can be controlled in seconds, and through a targeted management of temperature the quality of the facade coating can be improved.
As an example of how an installation can be optimised with the help of infrared radiators, Heinz Justen of Deutsche Mechatronics pointed to drying glue. Trials had shown that the machine environment can become undesirably warm through the use of hot air drying. On the other hand, with infrared drying, absorption is impaired by the ensuing dampness. The optimum solution for drying glue with a water component of between 30-50 % was air drying combined with infrared radiation. By means of a modular construction of the installation, the ratio of air to infrared can be adjusted as required. Because of this variability, the speed of the installation was increased, the desired air flow results in a much more efficient use of energy, the installation stays cooler while the product warms up faster.
Dr. Joachim Natrop of Bielomatik Leuze started by giving the participants an outline of the different processes which are used for welding plastic. After an explanation of the advantages and disadvantages of vibration welding, laser welding and welding with infrared heat, he then went on to some interesting new test results. Steering oil tanks are bonded from two separately manufactured halves. Since the tank consists of polyamide with 30% fibreglass, with the attrition caused by vibration during welding it develops lint, which adversely affects the welding results and especially the appearance of the finished product. The lint can later become loose and is such a problem in the tank that a large expenditure on cleaning is necessary in order to remove it. Because of the low viscosity and the high melting point of polyamide (6.6), welding is unsuitable with direct-contact heating elements. The process can be considerably improved with infrared and vibration welding. The surface of the plastic components are first melted without direct heat using infrared rays, and then welded through vibration. Hardly any attrition develops in the initial melting phase of welding. As the structure of the steering oil tanks is complex, the infrared heaters adapt to their contours during welding. A gold reflector in combination with a metal focusing mask directs the ray onto the welded joint.
Amongst the seminar participants, a large proportion of whom were from the auto industry, there was intense discussion about, for example, the right wavelength for certain materials, colours and penetration depth, and about the working life of infrared radiators under different environmental conditions.
Heraeus Noblelight GmbH
Reinhard-Heraeus-Ring 7 63801 Kleinostheim
Press contact: Dr. Marie-Luise Bopp,
Tel. 06181 35 8547
Heraeus Noblelight GmbH, based in Hanau, with subsidiaries in the USA, United Kingdom, France and China, have an international position amongst the market and technology leaders in the manufacture of special light sources. In 2006, Heraeus Noblelight posted annual sales of 88 million euros and employed a staff of 650 worldwide.
The company develops, manufactures and markets infrared radiators and ultraviolet lamps for applications in industrial manufacturing, environmental protection, medicine and cosmetics, research and analytical measurement processes.
The precious metals and technology company, based in Hanau, is a family concern, active worldwide, whose business interests include the fields of precious metals, sensors, dental and medical products, quartz and special light sources. With sales of over 10 billion euros and more than 11,000 employees worldwide in over 100 companies, Heraeus has for 155 years been an internationally recognised precious metals and plastics specialist.
Contact partner:
Herr Dipl.-Ing. ,Dipl.-Wirtsch.-Ing. Heinz Justen
Dipl.-Ing.
Dipl.-Wirtsch.-Ing.
Heinz Justen
+49 (0)2443 807-0