| 摘要 |
PURPOSE: To obtain a mud material which is used for closing a tap hole after discharging the molten iron and molten slag in a blast furnace from the tap hole, deals with prolonging of tapping time and a trend toward a higher molten iron temp. and has the corrosion resistance higher than heretofore. CONSTITUTION: This mud material for closing the tap hole of the blast furnace is formed by adding a proper ratio of a binder to 100 parts main raw material consisting of one or >=2 kinds among silicon carbide, chamotte, carbon, agalmatotite, clay, silicon nitride, silicon nitride iron and metallic powder. Alumina and magnesia are added in addition to this binder to the main raw material at 15 to 400 parts in total in such a manner that the ratio of the magnesia/ alumina by weight attains 0.1 to 0.6. As a result, the corrosion resistance and wear resistance are improved as compared with the conventional mud materials and the dealing with a blast furnace operation of a high tapping ratio is possible. Since there is no increase in the bore even if a hole of a large bore is opened from the initial period, the long-term tapping is made possible. The excellent performance capable of tapping the tapping slag in the furnace up to the last with good balance is thus exhibited. |
