| 摘要 |
PURPOSE:To obtain tuyeres which are hard to deform by thermal deformation of bottom refractories and can maintain the opening area of flow passage for coiling gases uniformly in all parts despite deforming by burying plural pieces of small diameter pipes for blowing of cooling gases in the circumferential wall parts of a pipe for blowing of oxidative gases and forming both no one body. CONSTITUTION:The circumferential wall part 10a of a pipe 10 for blowing of oxidative gases is walled thickly to a certain extent, and plural pieces of recessing grooves 11 along the axial line direction of the pipe 10 are provided circumferentially on the outside surface thereof at constant intervals from the top end of the pipe 10 down to near the bottom end thereof. Small-diameter pipes 12 of the same inside diameter are fitted in the respective grooves 11, and are fixed by build-up welding 13, etc. in the void parts of the grooves 11. The outside shape of the pipe 10 is finished to a cylindrical shape. Such pipe is inserted through a shell 3 of the furnace bottom and refractories 4 and is stuck to the refractories 4. If cooling gases are blown through the annular grooves 14 communicating with the pipes 12 and the pipes 12, the tuyere is cooled, and since the pipes 12 are of the specified inside diameter and specified intervals between each other, no deviation is produced in the rate of ejection of the gases. Since the pipes 10, 12 are in one body, the tuyere pipe has high strength. |
