1. Spheroidization
Select the spheroidizing method of the dam type spheroidizing ladle rushing method, select the mixed rare earth spheroidizing agent with a mass fraction of 5% ~ 6% magnesium and 0.4% ~ 0.6% rare earth, and add 1.20% ~ 1.30% of the spheroidizing agent. Use the carbon and silicon analyzer in front of the furnace to detect the carbon and silicon components of molten iron, and adjust them according to the results measured by the analyzer ω (C) 3.65% ~ 3.80%, ω (SI) is 1.40% ~ 1.60%, and when the temperature of molten iron is raised to about 1440 ℃ ~ 1460 ℃, the outlet water is spheroidized to control the outlet water. The pouring temperature shall be controlled between 1370 ℃ and 1390 ℃
2. Inoculation treatment
The subcooling degree of molten iron after spheroidizing treatment is large, and high-quality scrap steel + carburizing agent is used（ ω （C）≥98.5%， ω （S）≤0.030%， ω (N) ≤ 0.025%). In addition, wear-resistant pump body castings need to obtain strength, hardness and other properties, so proper inoculation is required to prevent the formation of carbides on the one hand, and on the other hand, to prevent the emergence of a large number of ferrite due to intensive inoculation. Therefore, the following inoculation treatment process is determined: inoculant with a mass fraction of 0.40% ~ 0.50% is added at the bottom of the ladle, A special funnel is used in the pouring process to add 0.10% ~ 0.15% mass fraction, 0.2 mm ~ 0.7 mm particle size long-acting inoculant.