The performance and advantages of breathable brick

existbreathable brickIn terms of working performance, on the one hand, it needs to accept the contact of molten steel with a temperature of 1600-1700 degrees Celsius, on the other hand, there is a continuous flow of cold air blown into the bottom of the argon gas, which forms a high thermal stress, that is, the temperature is quenched and heated, which leads to cracks. Breathable bricks Due to the refractory materials used for many times, periodic rapid cooling and rapid heating are prone to cracks and shedding near the working surface. Oxygen burning and oxygen blowing cleaning. After pouring the molten steel into the ladle and turning the ladle and pouring the slag, the breathable bricks should be cleaned. Oxygen blowing cleaning, and cleaning the residue and residual steel on the working surface to ensure the cleanliness of the working surface and the clear gas passage. However, when the amount of oxygen blowing is slightly larger, the breathable brick will be burned, and the ultra-high temperature above 2000 degrees Celsius and strong oxidation will damage the breathable brick. It has great damage. Corrosion. It is mainly caused by the corrosion of molten steel and the infiltration of molten steel through the pores to the inside of the breathable brick, causing damage to the structure, and then causing structural cracking and falling off. opening rate and service life.

The measures to improve and ensure the blowing rate are as follows: carefully design the gas channel according to the application conditions, optimize the air channel structure, and improve the masonry method. For example, laying 2 pieces of breathable bricks. Careful operation and maintenance. Clean the slag and slag, and use oxygen or other gases (nitrogen, carbon dioxide gas, etc.) to clean the surface of the breathable brick to ensure the cleanliness of the airway. The entire operation process: tapping, refining, pouring, and ventilation cleaning should be carried out smoothly, as far as possible. Shorten the interval time. You can also use the gunning material. After the air-permeable brick is cleaned, the gunning material is sprayed on the surface of the air-permeable brick. The residual heat of the air-permeable brick is sintered by the gunning material to form a honeycomb mushroom-shaped sintering. layer, which can not only ensure the permeability of the breathable brick, but also avoid the penetration of the molten steel.

The damage of the breathable brick is related to the raw material, shape and structure design of the refractory material and the application environment. The research results show that the good quality particle gradation and the reasonable design of the breathable brick structure can improve the thermal shock stability and slag resistance of the breathable brick , and then improve its performance. There are many factors that affect the service life of the breathable brick, but thermal peeling and oxygen cleaning are the important reasons for the damage of the breathable brick. By adding silicon nitride, Sialon and other additives in the matrix, the breathable brick has the same The molten steel is not wet and other characteristics, which reduces the corrosion loss rate. Reasonable planning of the mixing time and mixing intensity of air blowing can reduce the damage of breathable bricks. To prepare breathable bricks for ladle with excellent performance, the research focus should be concentrated on the following aspects: Under the premise of satisfying the refined process, select excellent additives, additives and aggregates to form a high-temperature solid solution phase during the heat treatment process to improve the thermal shock resistance of the material. Develop a new sintering process to prepare breathable bricks with special functions.