Automotive suppliers worldwide rely on the leading melting furnace technology from StrikoWestofen (Gummersbach, Germany) for the production of their cast parts. Now the owner-managed Polish foundry Lenaal (Radom) is operating a tilting aluminium melting and holding furnace of StrikoMelter MH II type. The technology was developed in Gummersbach, whereas production and delivery went via the StrikoWestofen factory in Strzelce Opolskie (Poland). In daily operation, the system does not only produce melt of excellent quality – it is also extremely economical: the furnace replaces a total of two crucible melting furnaces which, at 120 m3 of gas per tonne of molten aluminium, consume almost twice the amount of the StrikoMelter. Thanks to its low gas consumption, Lenaal’s investment will pay for itself completely after only about two years of operation. Further savings result from the considerably improved material efficiency of up to 99.7 percent and considerably extended maintenance intervals with short down times.
Maximum casting quality is one of the most important production criteria for the owner-managed Polish foundry company Lenaal located in Radom. The well-known supplier of the German automotive industry manufactures die-cast aluminium components which are often safety-relevant. A homogenous melt free of oxides and with a low density index is therefore vital in the truest sense of the word. To continue to stand up to international competition, however, the company management decided in 2012 to purchase a StrikoMelter aluminium melting and holding furnace from StrikoWestofen. “We have had more than 20 years of experience in die-casting, and we supply customers in Europe and the United States,” explains Lukas Pokusa, junior head and production manager of Lenaal. “Economy is a vital factor in international competition besides high casting quality. Thanks to the market-leading StrikoMelter technology from Gummersbach, we now have a decisive competitive advantage.” In comparison with the crucible melting furnaces used up to now, the special efficiency of StrikoMelter melting furnaces almost halves the energy consumption per tonne of molten aluminium.
This is made possible by the targeted recovery of the exhaust heat from the melting process in order to preheat the material to be melted. For this purpose, StrikoMelter melting furnaces have a special shaft geometry which combines the melting phases of preheating, heating and melting in one single shaft. This effective principle of integrated heat recovery reduces the energy requirements of the actual melting process, thus achieving considerable savings with regard to fuel consumption. In addition, the rapid melting process in the melting zone reduces metal loss due to oxidization. StrikoMelter melting furnaces thus achieve a material yield of up to 99.7 percent.
Computer-assisted development tools make a good thing even better
“Our StrikoMelter furnaces are based on knowledge of decades of experience, but it was possible to improve those even more using modern development tools such as computational fluid dynamics and the finite element method,” explains Rudolf Riedel, CEO and development manager of the StrikoWestofen Group. “Our excellent results can only be achieved thanks to process-optimized design and the exact realization of refractory lining and furnace chamber geometry. It is therefore not rare for our furnaces to have service lives of over twenty years.” StrikoMelter melting and holding furnaces thus offer decisive indirect benefits too: the shortened down times increase the productivity of the entire system and make a substantial contribution to economical operation. If it should be necessary to replace components, however, trained service personnel and original spare parts guarantee rapid and durable maintenance. “Our production facility in Poland allows us to provide service close to the customer,” Riedel explains.