The firing process is a very important process in the production of refractory bricks. During the firing process, it will not only determine its performance and quality, but also have a direct impact on the quality of the molding. Then which factors will affect, mainly refer to the following three aspect:
1. The deposition of gas phase
Many smelting furnaces and flame furnaces will produce CO decomposition and volatilization of lead, zinc and alkali metal oxides during the production process, and deposit in the pores and joints of refractory bricks, causing brickwork to crack, deform and chemically corrode. This phenomenon is more prominent in the upper part of blast furnace, blast furnace, shaft kiln and coke oven, and even becomes the main reason for the damage of these parts.
2. the effect of drastic changes in temperature
Many kilns, especially intermittent operation kilns, have large temperature fluctuations, and sudden changes in temperature will generate large internal stresses, which will cause the bricks to crack and peel, and deform or collapse in severe cases. Such as steel-making converters, electric arc furnaces and copper-tin smelting reverberatory furnaces, the furnace temperature during the smelting period can reach 1250～1650℃, but after slagging, steel tapping and copper tapping, the temperature in the furnace drops sharply to 600～800℃, and the temperature is within a short time. The fluctuation is too fast and too large, causing the brick body to have a large stress, causing cracks, peeling and damage.
3.slag corrosion
Corrosion caused by the physical and chemical effects of molten slag and molten metal or dust-containing corrosive gas.
Therefore, in the firing process of refractory bricks, we must pay attention to the influence of these factors to improve the production quality and use performance of the products, so as to better ensure the quality of the bricks and achieve the user's efficiency.
