The molten iron ladle is placed under the mouth of the electric furnace, and the molten iron smelted by the electric furnace flows into the ladle for transfer.
The temperature of the molten iron in the ladle is generally 1300~1450℃. The lining of the molten iron ladle will be eroded and worn by high-temperature molten iron, and the thermal stress caused by thermal shock will cause thermal expansion damage. During the period when the molten iron ladle is filled with molten iron, it will be subject to chemical erosion by molten iron and slag and oxidation by the air.
Material selection is very important. When the molten iron is contained in the molten iron, it will be damaged by erosion and high-temperature oxidation. After the molten iron is emptied, the temperature will drop sharply, causing the furnace lining to be quenched. The lining is repeatedly subjected to rapid cooling, rapid heat, and erosion by slag iron. The lining must be made of refractory bricks or refractory castables with good thermal shock resistance, erosion resistance and oxidation resistance.
According to the size of the lining, refractory bricks of different materials such as clay bricks, high alumina bricks, magnesia bricks and magnesia carbon bricks are selected for the furnace lining. The entire lining is also made of refractory castables. The lining is made of low cement castables and the working layer is aluminum carbonized. Silicon castable or spinel castable.
The service life of bag linings built with refractory bricks is related to the quality of the refractory fire bricks used. Small bags are generally made of clay bricks or high-aluminum bricks. Clay bricks have good thermal shock performance and low cost, but their corrosion resistance is not very strong and their service life is Not very long either. The service life of high alumina brick lining will be longer than that of clay brick. But if the package is large, aluminum silicon carbide bricks must be used, but the overall cost is higher. The use of bricks will not cause secondary shrinkage at high temperatures, and the strength and corrosiveness also have good results.
If refractory castables are used as a whole, the problem of mortar joints in refractory bricks can be solved. The overall pouring has strong air tightness. If the refractory castable material is selected, the service life is not less than that of high-grade refractory fire bricks. But we need to consider the issues of baking and judging the buns. If you use refractory castables from the northwest generation, you cannot use refractory castables for lining because the climate does not allow it.
Whether it is appropriate to use refractory castables or refractory bricks does not depend on the construction method. The key lies in the grade of refractory material castables or refractory fire bricks used. It is important to consider that good thermal shock resistance, strong resistance to slag erosion, and low resistance to thermal expansion are the key to material selection. Whether it is refractory castables or refractory bricks, each has its own characteristics, advantages and disadvantages, and the key is to choose the right material. , and at the same time, regional conditions are the most important thing to consider.
