A method for improving the mechanical dephosphorization of iron scale of a low-carbon cold heading steel
wire rod belongs to the technical field of steel rolling.
Processing steps and control technical parameters are as follows: finish rolling
inlet temperature is controlled to be 920 DEG C-950 DEG C, and the finish rolling temperature rising range is controlled to be 80 DEG C-100 DEG C; the
spinning temperature is controlled to be 880 DEG C-920 DEG C; the opening times and a heat holding cover of an
air cooling line and the opening degree of a fan are regulated, the
cooling rate of the
phase front section of a spun steel
wire rod is controlled to be 2-3 DEG C / s; the temperature of the spun steel
wire rod is controlled to be 760 DEG C-740 DEG C when the spun steel wire rod enters the heat holding cover, and the heat holding cover is uncovered at the temperature being 620 DEG C-600 DEG C; and the temperature of the spun steel wire rod is controlled to be 580 DEG C-600 DEG C when the spun steel wire rod is discharged from the heat holding cover, the fan is additionally arranged when the spun steel wire rod is discharged from the heat holding cover, the
cooling rate of the spun steel wire rod passing through a temperature zone being 5000 DEG C-400 DEG C rapidly is controlled to be 3-5 DEG C / s, and the passing time is controlled to be 15-25s. The method has the advantages that the phase structure conversion phenomenon in an FeO layer in the iron scale on surface of a hot rolling steel wire rod is reduced obviously, the mechanical dephosphorization is improved obviously, and the wire breaking rate and the loss of a die in the user pulling process are reduced.