Process practice to improve the quality of billet core of 70 steel continuous casting
In order to improve the core quality of 70 steel continuous casting billet,industrial experiments were car-ried out by adjusting the drawing speed,superheat,secondary cooling specific water quantity and pressing process.The results show that when the process is 2/2/4/7/7,the central carbon segregation can be improved by casting with low superheat,high drawing speed or lower secondary cooling specific water volume.However,when casting at 2.60 m/min high drawing speed or 0.46 L/kg low secondary cooling water ratio,the cooling speed of the casting billet is reduced,resulting in low solid phase ratio at the 1 # drawing leveler and insufficient thickness of the billet shell,resulting in intermediate cracks during pressing.When the process is 0/2/5/7/6,not only the middle crack is obviously improved,but also the center carbon segregation is effectively controlled,and the measured center carbon segregation is only 1.02,and the quality of the billet core is good.
万方数据
维普
