The invention discloses a production method for hypoeutectic cast
pig iron. The production method is characterized in that the
pig iron comprises the following chemical elements by
mass fraction: 3.400-4.000% of C, less than or equal to 0.600% of Si, less than or equal to 0.100% of Mn, less than or equal to 0.040% of P, less than or equal to 0.030% of S and less than or equal to 0.040% of Ti. The production method comprises the following working procedures: (1),
blast furnace smelting: 65-70 wt% of a high basicity sinter and 30-35 wt% of
pellets are taken as raw materials, and the basicity of the high basicity sinter is 1.90-2.00; during
smelting, the content of Si is controlled to be less than or equal to 0.50 wt%, and the furnace
slag binary basicity R2 is controlled to be from 1.15 to 1.20; (2), electric furnace
smelting: an electric furnace is heated to smelt iron by utilizing a
blast furnace molten iron and waste steel method; a first
inoculation treatment is performed when the iron is discharged, and the addition amount of an inoculant is controlled in a range of 2-3 kg / t molten iron; (3),
casting moulding: the inoculant is added along an iron flow during
casting to perform second
inoculation treatment, and the addition amount of the inoculant is less than or equal to 2 kg / t molten iron. According to the production method for the hypoeutectic cast
pig iron, factors, such as utilization factors, yield and hot
air temperature, are improved; furthermore, the comprehensive
coke ratio is remarkably reduced; the problem of thick
graphite heredity in
casting industry is solved.