Method for filling gap between bricks and lining of tapping hole of converter

Abstract

The invention discloses a method for filling a gap between bricks and a lining of a tapping hole of a converter, and belongs to the field of converter steelmaking. The method comprises the following steps of: (1) preparing slurry, wherein the slurry comprises more than or equal to 88 percent of MgO, more than or equal to 2 percent of CaO, and less than or equal to 4 percent of SiO2; (2) testing the performance of the slurry, wherein under the condition that the temperature is 110 DEG C and the time is 24h, the heating linear change of the slurry is -1.5 to 0 percent, the density is more than or equal to 2.45g / cm<3>, and the withstand voltage is more than or equal to 8MPa; (3) putting the slurry into a blowing tank in advance, controlling the pressure of an air source, mixing the slurry and water on line according to the proportion of (1:1)-(1:1.5), and directly filling the gap between the bricks and the lining of the tapping hole of the converter by spraying the slurry by a spraying pipe; (4) regulating the pressure, controlling the jet velocity of the spraying pipe, quickly filling the gap between the bricks and the lining of the tapping hole of the converter by utilizing the characteristic of high liquid fluidity of the slurry, and controlling an inner hole of the tapping hole to form a small and round inverted horn shape; and (5) sintering for 12 to 14 minutes after the gap between the bricks and the lining of the tapping hole of the converter is filled by using the slurry. The method can improve the service life of tapping holes and reduce labor intensity.

Description

technical field [0001] The invention relates to the field of converter steelmaking, in particular to a method for filling the gap between a converter taphole brick and an inner lining. Background technique [0002] The converter taphole is the only channel for molten steel to enter the ladle from the converter. When tapping, due to the high-temperature molten steel, slag friction erosion and oxidative chemical erosion, the life of the tapping hole is very low, and it needs to be repaired and replaced continuously, which will not only affect the production cycle, but also affect the quality of molten steel and production stability. , thus replacing the taphole brick is one of the essential processes in converter steelmaking. There is a gap of about 2.5cm between the newly replaced taphole brick and the lining of the converter. After the taphole is replaced, the gap between the two needs to be filled. Whether the gap between the taphole brick and the lining can be completely...

AI Technical Summary

Problems solved by technology

If the gap between the taphole brick and the lining cannot be effectively filled and filled, and the shape of the inner opening of the taphole is irregular, the accident of molten steel piercing the taphole may occur during the use of the converter, and the taphole will block the slag will also be very poor

At present, the gap between the converter taphole brick and the inner lining is generally filled by manual feeding of fine-grained magnesia, which mainly has the following problems: First, the accuracy of manual feeding is poor, it is not easy to fill, and it is easy to leave gaps to enter molten steel , resulting in the accident of molten steel piercing the tap hole and the difficulty of replacing the tap hole next time; secondly, the shape of the inner mouth of the tap hole is not easy to control, uneven, and the effect of slag blocking is poor, which may easily cause the accident of slag returning to phosphorus; finally, the sintering time It lasts about 22 minutes, it is not resistant to high temperature steel slag erosion, and the service life of the tap hole is low. The tap hole needs to be replaced once every 150 heats, which wastes materials and is labor-intensive. Fourth, there are certain safety hazards