Hertwich Engineering received an order from Exlabesa, an independent extruder based in Europe, for a multi-chamber melting furnace that will increase the capacity of its casthouse in Padrón (Spain) to 60,000 tons per year. The furnace, which has a capacity of 130 tons per day, will be designed to process a relatively wide range of scrap. To remelt the loose and moderately contaminated scrap, an Ecomelt-PR furnace with preheat ramp, melting chamber and main chamber will be installed. Commissioning of the furnace is scheduled for mid-2020.
The scrap to be melted is transferred onto a ramp in the preheat chamber by an automatic charging unit. The material is heated to approximately 932°F (500°C) in the preheat/melting chamber to remove adhering organic compounds. For a furnace with a daily melting capacity of 130 tons, Hertwich specifies two charging cycles per hour (each with 3 tons of scrap).
The preheated material is pushed from the ramp into the melt bath. An electromagnetic liquid metal pump ensures the melt transfer between both furnace chambers and the availability of the required energy for melting in the melting chamber. The melt level in the melting chamber and the melting rate can be adjusted by this liquid metal pump. During the melting process, the scrap remains submerged at all times in order to avoid oxidation losses.
The temperature level in the main chamber from which the melt is tapped for casting is approximately 1832°F (1000°C). The heating system uses the energy in the flue gases to heat the combustion air.
Exlabesa operates a total of 22 extrusion lines at seven production centers in U.S., U.K., Spain, Germany, Poland and Morocco.