Preparation process of steel for crown cap cold forming

The invention provides a preparation process of steel for crown cap cold forming. The preparation process includes the procedures of LF refining, specifically, high-aluminum refining slag is added after submerged arc operation, the amount of the slag added to molten steel per ton is 4-6 kg, the melting point is controlled to be 1500-1700 DEG C, and constituents of the high-aluminum refining slag are as follows: 49% or over of CaO,1.5% or less of MgO, 1.5% or less of SiO2, 40% or over of AL2O3 and 0.5% or less of moisture; heating, specifically, the heating temperature is 1145-1175 DEG C; rolling, the final rolling temperature is 880-900 DEG C; and laminar cooling, specifically, the coiling temperature is 605-635 DEG C, and the up-down specific water flow is 0.75:1. According to the preparation process of steel for crown cap cold forming, many process procedures are optimized, the value r and the value n are increased, the sum of grades of nonmetallic inclusions of molten steel is averagely decreased by about