30CrMo circular tube billet steel casting blank internal quality control method

The invention relates to the field of ferrous metallurgy, particularly a 30CrMo circular tube billet steel casting blank internal quality control method. The invention aims to provide a 30CrMo circular tube billet steel casting blank internal quality control method for integrally enhancing the rolled material quality control and improving the circular tube billet steel casting blank internal quality in the 30CrMo circular tube billet steel casting blank production process. The method comprises the following steps: a. carrying out converter smelting; b. refining molten steel in an LF (ladle furnace); c. carrying out RH refining; and d. finally, continuously casting molten steel. The electromagnetic stirring parameters of the crystallizer are as follows: the stirring current is 350-400A, and the frequency is 2-4Hz; the solidifying tail end electromagnetic stirring parameters are as follows: the stirring current is 200-300A, and the frequency is 6.0-8.0Hz; the superheating temperature is controlled at 15-30 DEG C; and the specific water quantity for secondary cooling is controlled at 0.21-0.29/kg steel. The method is especially suitable for producing the 30CrMo circular tube blank and steel casting blank with the cross section of phi350mm.