can be advisable for commercial reasons and reasons of energy policy. Some of the advantages of medium-frequency systems are listed below:
- starter blocks and laborious starting procedures are not required
- no laborious scrap drying or dry storage required
- increased electrical efficiency through charge operation
- melting with higher output and shorter melting times
- improvement of thermal efficiency due to the smaller furnace size
- lowest possible energy consumption with optimum flexibility
- saving of maintenance and repair cost
- increased operating safety
- reduction of the fireproofing costs for the same throughput
- increase in overall economy
- old energy consumption with 13-t furnace with mains frequency, 750 kWh/t (2,800 kW)
- new energy consumption with the same furnace, 640 kWh/t (4,800 kW – 250 Hz)