| 摘要 |
PURPOSE:To improve durability by inserting porous cylindrical refractories for blowing gas having prescribed pores into an immersion nozzle bodies consisting of prescribed porous refractories. CONSTITUTION:Porous cylindrical refractories 4 for blowing gas having pores of 0.04-0.08mum average pore size d2 and 0.005-0.055mum average distance l between pores are inserted into an immersion nozzle body 2. The body 2 is formed of porous refractories having pores of 0.001-0.01mum average pore size and 0.1- 0.2mum average distance between pores. The immersion nozzle is improved in the tendency to clogging of the inside hole of the nozzle and cracking as well as in the durability. |
