| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for preventing the sticking of oxide in molten steel to the inner surface of an immersion nozzle. SOLUTION: A casting of the molten steel is performed under condition of using the immersion nozzle 1 satisfying the formula (b) to the opening cross sectional area S (m2) at the outlet of a tundish 2 with the formula (a) and the cross sectional area A (m2) in the nozzle and satisfying the formula (d) to the molten steel head index H (m) in the inner part of the immersion nozzle with the formula (c) and satisfying the formula (e) to the inert gas amount W (m3(normal)/s) blown into the molten steel 10 passed through in the immersion nozzle. S=Q/ρ×(2gh)1/2}...(a), 2<A/S<5...(b), H=(2g)-1×(ρc)-2×(Q/ A)2...(C), 0.08<H<0.5...(d), 1×10-6<W/Q<5×10-6...(e). Wherein, Q: the flowing amount (kg/s) of the molten steel,ρ: the density (kg/m3) of the molten steel, g: the gravity acceleration (m/s2), h: the molten steel depth (m) in the tundish and c: flowing passage factor (-).
|
