In the classification of magnesia bricks, what are breathable magnesia bricks?

For magnesia bricks, some conditions of use are to use the high porosity and high air permeability of the product. At present, the argon gas permeable corundum bricks widely used in steel mills are blown at the bottom of the ladle, and the metal is smelted with gas, that is, corundum bricks for liquid are smelted with gas. The particles of the same size are used, and the particles are tightly bonded by fillers and binders during the sintering process, so that the product becomes a solid block, and the particles of the same size determine the shape and size of the pores. If it is necessary to increase the air permeability of the product, it is also necessary to add ember additives. The particle size should be the same as that of the filler, and the shape should be the same as that of the filler. Magnesia brick manufacturers

Porous and breathable magnesia bricks used for blowing metal, using corundum magnesia has certain advantages. For industrial application of breathable corundum bricks, 80% of No. 63 fused corundum can be used as granular material, and the mixture of industrial alumina (65%) and refractory clay (35%) can be used as binder, which is 20%. The binder should be used in a barrel mill. It is finely ground together, and the content larger than 60 μm cannot exceed 1% to 1.5%. The mud is kneaded on a wet mill for 10 minutes, and the mud moisture is 4.3% to 5%, and then sieved on a sieve with a mesh size of 5mm. The bricks are formed on a hydraulic press with a pressure of 35MPa, and the bricks have a density of 2.60g/cm3. The products are fired in tunnel kiln or inverted flame kiln, the firing temperature is 1570℃, the heat preservation is 22±2h, and the total firing time shall not be less than 150h.

There are many ways to make air-permeable corundum bricks. 20% of the binder is made from corundum waste (60%) and clay (40%), and the moisture of the mud is 4%~5%. It is 2.60 g/cm3:, fired in a tunnel kiln for 86h, the firing temperature is 1560℃, and the temperature is kept for (5±1)h.

Others use magnesia brick as aggregate, pure calcium aluminate cement and SiO2 ultrafine powder as binder, phosphate as dispersant, and use ultra-low cement castable technology.