CONVERTER STEEL MAKING METHOD

A converter steelmaking method is proposed that allows a larger amount of cold iron source to be used in a refining process of a cold iron source and molten pig iron contained in a converter-type vessel, while preventing the cold iron source from remaining unmelted, without compromising the productivity. In the converter steelmaking method, molten pig iron is subjected to a dephosphorization process to obtain dephosphorized molten iron, and the obtained dephosphorized molten iron is subjected to a decarburization process to obtain molten steel. For the dephosphorization process, before the undephosphorized molten pig iron is charged into a first converter-type vessel, a first cold iron source in an amount meeting Formula (1) below is charged all at once into the first converter-type vessel, and then the undephosphorized molten pig iron is charged and subjected to the dephosphorization process. The obtained dephosphorized molten iron is discharged into a molten metal receiving vessel and held in the molten metal receiving vessel. After a second cold iron source is charged all at once into the first converter-type vessel in which the dephosphorization process has been performed or a second converter-type vessel different from the first converter-type vessel, the dephosphorized molten iron held in the molten metal receiving vessel is charged and subjected to the decarburization process. %Ws0 ≤ 0.1186T - 134 (%Ws0 ≥ 0) ··· (1), where %Ws0: a ratio (%) of the first cold iron source to a sum of the first cold iron source and the charge amount of the undephosphorized molten pig iron, and T: a temperature (°C) of the undephosphorized molten pig iron.