| 摘要 |
PURPOSE:To provide a bottom blowing gas changer which can prevent generation of a tuyere trouble and change in the quality of a steel by constituting said changer in which the bottom blowing gas of a bottom blown converter is changed to the required gas without increasing the pressure in a piping prior to exposure of the tuyere in the stage of tilting the converter when changing said gas. CONSTITUTION:The time (t) required until a tuyere 3 is completely exposed above a molten steel 2 according to tilting of a converter 1 is preliminarily determined. The magnitude of the capacity V of the piping from a shut-off valve 10 in the position near the tuyere provided to a piping 13 up to the tuyere 3 is limited in order to complete the blowing of the preceding gas G1 remaining in the piping 13 into the converter within the above-mentioned time (t) in the stage of changing the gas to be blown to the converter 1 (for example, in the stage of changing O2 to N2). More specifically the piping capacity V from the valve 10 to the tuyere 3 is made substantially small to shut off the piping with the valve 10 and to decrease the amt. of the gas G1 remaining in the piping part so that the complete releasing of the gas G1 into the converter 1 is finished within the time (t). As a result, the failure, cracking, etc. of the tuyere mushroom, brick, etc. are prevented and the life of the tuyere is extended. |
