| 摘要 |
PURPOSE:To make it possible to alter a gas flow amount within a wide range and to refine a steel from a high carbon steel to a low carbon steel by the same converter by a method wherein an assembled pipe body comprising plural pipes with a small diameter is provided in an inner pipe of a tuyere of a bottom blown rotary converter in such a manner that said pipes are spirally turned at an appropriate angle against a pipe axis and said inner pipe is inserted into an outer pipe. CONSTITUTION:Oxygen gas for refining is injected into molten steel from a double pip tuyere 2a for blow refining of a bottom blowing converter and a hydrocarbon gas for cooling and protecting the tuyere from an outer pipe 2b to refine said steel. In this case, an assembled pipe body 6 comprising pipes 7 with a small diameter with an appropriate angle against a tuyere central axis is provided within an inner pipe 2a. This inner pipe 2a is divided into plural jet cores by said assembled pipe body 6 to disperse the energy of the gas jet and an oxygen sending amount can be increased or decreased to a large extent without forming problems such as spitting or slopping. Therefore, in case of refining a high carbon steel, P can be removed by oxidation while decarburization due to FeO is controlled and a steel ranging from a low carbon steel to a high carbon steel can be refined by the same converter. |
