... /heating furnace Main function : Smelting Steel scrap ,iron scrap, sponge iron / DIR ,copper scrap , aluminum alloy, heat treating ,through ... scrap or 50% to 80% iron scrap with 50% to 20% Sponge iron / DIR or bar, billets ,spare parts . Working relation: induction melting ... features: Aluminum alloy frame furnace ,cheaper ,life middle , melting rate middle . Steel frame furnace : expensive , life long ...