is essential for induction furnaces if the charge material is stored in the open instead of indoors. When operating induction furnaces, care must be taken to ensure that no fluids get into the melt. 1 cm3 of fluid getting into the bath will expand suddenly in volume to 500-600 cm3. This is referred to as a water vapour explosion. With medium-frequency furnaces, scrap drying can be dispensed with provided that the scrap is handled accordingly. The operator must at all times ensure that material is not charged into the sump, but that there is always enough solid material on top of the melt so that it will be dried before coming into contact with the melt.
The former practice of heating scrap up to temperatures of approx. 200 °C is no longer viable nowadays because of increased energy costs. The material made up 60% and the container the remaining 40%. The achievable melting performance increase is significantly lower than that indicated by the theoretical calculations.