Smelting method of medium-high-carbon sulfur-lead complex system free-cutting structural steel

The invention discloses a smelting method of medium-high-carbon sulfur-lead complex system free-cutting structural steel. The smelting method comprises the processes of primary smelting, LF refining and vacuum degassing refining, wherein the process of primary smelting involves an electric furnace or a converter, and during tapping, sulphur or ferrous sulfide blocks are used according to the requirements for the original S content in steel and the components of steel balls and the desulfurization rate of an initial slag system during special steel tapping to achieve resulfurization; lime and high-purity quartz sand are adopted for preparing components of the main slag system, a deoxidizing agent and alloy containing C, Si, Al and Mn are taken as deoxidation alloying materials, and harmfuloccluded foreign substances are well controlled. By means of the smelting method, consideration to the good gas removal effect and good control over lead content can be guaranteed, and the situation that the gas content rises