1 Improve smelting conditions
1) By insulating the ladle, the heat loss of molten steel is reduced, thereby reducing the refining temperature and time, and prolonging the service life of refractory materials.
2) Reduce the amount of slag in the converter, thereby reducing the amount of magnesia-carbon bricks dissolved in the slag, thereby increasing the life of refractory materials.
3) Appropriately increase the amount of lime, increase the alkalinity and viscosity of the slag, and reduce the penetration and melting loss of the slag to the refractory, thereby increasing the life of the refractory.
2 Improve the baking quality of ladle
1) The baking time before the ladle goes online is increased from 36h to 48h, and the temperature is raised strictly according to the baking curve, and the holding time is guaranteed to meet the technological requirements, and the temperature when the ladle goes online reaches 900℃.
2) Reduce the turnover of ladle from 5 to 4, improve the efficiency of ladle turnover, reduce the processing time of the ladle, reduce the time interval for refilling the molten steel after the ladle is poured, and prevent stable fluctuations in the temperature of the ladle.
3 Strengthen the lining material
1) The characteristics of converter slag are strong oxygen origin, low alkalinity, and strong corrosive ability of permeability. It is necessary to increase the density of ladle bricks to strengthen its corrosion resistance.
2) Alternation of hot and cold is an important factor for the easy damage of the ladle lining. Improving the thermal shock resistance of the ladle magnesia carbon brick is beneficial to improve the service life of the ladle.
3) The magnesia-carbon brick is easy to be oxidized during the baking process of the ladle due to the higher carbon content, and the longer the baking time, the more serious the oxidation degree. Applying an anti-oxidation coating on the working surface of the magnesia carbon brick can greatly avoid the oxidation of the ladle during the baking process, thereby increasing the service life of the ladle.
4 Improve the masonry method of the ladle
1) The bottom of the ladle is changed to a pouring mode. On the one hand, the bottom of the ladle has good integrity and no brick cracks appear. On the other hand, the bottom of the ladle can be poured and maintained during the use of the ladle and when the ladle is off the assembly line, so as to avoid unpacking the bottom. Unlimited use of the bottom, reducing the consumption of refractory materials.
2) The area where the body position is susceptible to scouring by molten steel is a weak link and needs to be strengthened. It can be considered from two aspects: strengthening the material to improve the density and erosion resistance of the brick; increasing the thickness of the brick without changing the erosion rate Improve life. Or consider the above two points comprehensively to synchronize the life of the weakened area and the common location of the refractory material, thereby increasing the overall life of the ladle.
5 Maintenance method
1) Pouring and repairing the bottom of the package. Clean up the ladle slag at the bottom of the ladle, and then use corundum material for pouring and repairing. The thickness can be restored to the thickness of the original ladle bottom. Pay attention to not pouring too thick (not more than 50mm) to avoid separation of the pouring material and the bottom of the ladle during use. drum.
2) Digging and repairing the body. Excavating and repairing severely corroded areas can greatly increase the service life of the ladle lining.
3) Apply repair material to the wall of the package. Generally, one set of cladding wall should be used with multiple sets of slag line, which will easily cause the residual thickness of the cladding wall brick to be lower than that of the slag line brick, which will affect the service life. It is a kind of coating material used for the coating wall, which has micro-expansion at high temperature, is not easy to produce cracks, has good integrity, and can greatly improve the service life of the coating wall. The service life of the coating material is generally more than 20 furnaces. How to use it: Mix the spreading material with an appropriate amount of water in proportion, and stir evenly into a plastic state that is easy to spread. Clean up the slag pour surface of the ladle and other places where the slag is too thick, apply a small amount of paint several times, from bottom to top, on the wall of the package, and apply it to the thickness of the original package wall brick, generally about 50mm, and it will be immediately after solidification. can.