Intermediate cladding castable

After the intermediate cladding castable is cast and molded, it should be baked to a temperature of about 1000 °C after a small fire, medium heat and high fire, and then suddenly extinguished. The magnesia carbon brick manufacturer is cooled to normal temperature or low temperature (≤200 °C) and used again (due to temperature drop) Rapidly, it is often easy to cause longitudinal cracks in the castable. When used, the alkaline coating is applied or sprayed onto the intermediate cladding castable. After drying naturally, it is baked on the line. Usually, it is baked to about 1000 °C in 1~2 h. When pouring molten steel, the temperature of the molten steel is usually 1500. —1550 oC, the surface temperature of the backing of the alkaline working lining can reach above 1300 °C in a short period of time, and the tundish needs to be cooled down quickly after use. Therefore, some manufacturers use forced air cooling for rapid turnover. Or watering method, after the bag is over, the paint is applied or sprayed onto the intermediate cladding castable. In this cycle, the tundish castable lining of the tundish is caused by thermal shock and longitudinal cracks and transverse cracks, which cause cracks, and sometimes cracks parallel to the hot surface, which tend to cause spalling during turn-over, resulting in lining castables. Damaged.

Adhesion of intermediate cladding castable to work lining

At present, the tundish work lining has many coatings, so the performance of the coating is closely related to the service life of the tundish. During the use of the tundish, the molten steel temperature is 1500-1550 °C. The working lining paint is sintered at high temperature and high pressure due to the inclusion of clay, inorganic salts (phosphate and silicate). If it is used for a long time, it may be The coating is sintered with the intermediate cladding castable. The alkaline coating has good corrosion resistance, but the permeability of the anti-slag is poor. The slag passes through the working lining to reach the intermediate cladding castable. It reacts with the intermediate cladding castable, and it is easy to sinter the working lining and the intermediate cladding castable. Together, the working lining cannot be freely dropped when the tundish is used for turning over the bag, and can only be peeled off by manual force, thereby causing peeling damage.