| 摘要 |
PURPOSE:To prevent the erosion of a tuyere and to extend the life of the tuyere by setting the bore and space of a gas blowing nozzle constituting the tuyere according to the flow rate of the gas to be used at such a value at which the temp. of the refractories around the tuyere does not exceed the erosion transition temp. CONSTITUTION:The temp. distribution of the tuyere refractories 4 of the gas blowing nozzle 3 is determined by executing the computer simulation based on a finite-element method. The fine hole diameter (dmm) of the gas blowing nozzle 3 and the space between the fine holes of the nozzle 3 (Dmm) are thereby so set with respect to the required flow rate of the gas for the fine holes of the nozzle (QNm<3>/mm) that the working surface temp. of the refractories at the point A does not exceed the erosion transition temp. of the refractories 4 used, for example, about 1,000 deg.C in the case of an MgO-C brick and not exceed 1,000 deg.C in the case of an MgO brick. The nozzle is thus designed to obtain the cooling effect. Then the blowing gas for bubbling acts as a cooling gas in the designed tuyere for steel making. The temp. increase of the peripheral refractories 4 is thus suppressed and the eroding rate is considerably decreased. |
