Magnetic billet heating rivals conventional furnaces

A new process for non ferrous metal billet heating seems to be on the verge of making its way in the industry. The first magnetic billet heater was put into commercial operation at the German aluminium extrusion works Weseralu GmbH & Co. KG in July 2008 (Fig. 1). A further system has just been ordered by Sapa, the world's largest manufacturer of aluminium profiles, for installation at its Italian subsidiary in Bolzano. What is behind the new technology that seems to be quick in gaining acceptance? In 2004, Zenergy Power and Bültmann received funding from Deutsche Bundesstiftung Umwelt (DBU) (www.dbu.de), Germany's environmental funding agency, to develop an energy-efficient, highly homogeneous billet heater. The first proof-of-principle subscale device was developed and demonstrated to the public at the Hannover Fair in April 2005. With additional support from the DBU, a full scale device was designed, manufactured, and ultimately put into service at Weseralu in 2008. By being the early adopter of this technology, Weseralu receives significant advantages of low energy costs and billet temperature homogeneity compared to its competitors. In what follows, the performance characteristics and benefits of the first magnetic billet heater are described in detail.