Patent ID: 11925979
Assignee: INDUCTOTHERM, CORP.
Field: Materials, metallurgy (Chemistry)
Classification: CPC B  Y | IPC B

Claim 10:
11. A method of producing a large steel ingot by solidifying a molten steel supplied to a casting mold, the molten steel forming a riser part of the molten steel over a main part of the molten steel, the method comprising:
positioning an electric induction heating coil within the casting mold over a top surface area of the molten steel;
supplying continuously a variable power magnitude and a variable frequency to the electric induction heating coil;
selecting a directional solidification process relative to each of a size of the large steel ingot, a shape of the large steel ingot, and a chemical composition of the molten steel, the directional solidification process comprising a range of solidification power magnitude and solidification frequency parameters over a process duration;
adjusting simultaneously the variable power magnitude and the variable frequency supplied to the electric induction heating coil coordinately over the process duration to match the solidification power magnitude and the solidification frequency parameters of the selected directional solidification process; and
wherein the solidification power magnitude and the solidification frequency parameters are configured to maintain an induced power from the electric induction heating coil at a nominal induced power level from when the molten steel in the main part is in a molten state until at least the main part has solidified and such that the molten steel in the riser part is maintained in the molten state until after a lower main body part has solidified.