What is fused refractory (refractory bricks)

What is fused refractory? Materials are melted and cast into products. Electrolytic fritters are usually made with a three-citon electric arc furnace with a voltage regulator. The brick is melted in an electric arc furnace and then the melt is poured into a high temperature resistant mold. After cooling and annealing, it is cut into the desired shape Of the products that are known as fused refractories.

Fused refractory material with a large grain, compact structure, high mechanical strength, corrosion resistance and a series of excellent performance. Can manufacture large-scale products, mainly used for glass melting furnace. Glass industry rejection fused refractory materials are fused zirconia corundum brick and white corundum brick.

The fabric of the fusible brick is made of powder or granular. One of the granular material does not produce dust flying, can be used for large capacity furnace production, material composition is accurate, feeding can be mechanized. The melting of the batch material is carried out in an electric solitary furnace, and the energy of 3000 ° C or higher is obtained by concentrating the energy in the small space by the electric soldering, and the material is melted quickly. Pouring the furnace when pouring, so that the melt from the discharge port out of the flow through the trough into the prefabricated and assembled refractory model. The model can be made of quartz sand, corundum sand or graphite plate, requiring the model to have a fire resistance of not less than 1700 ℃, good air permeability and impact resistance, and does not react with the body and good thermal shock resistance.

In the process of electrothermal melting, the composition of the material will change, such as SiO2 will evaporate at high temperatures, and the reduction of Fe2O3 by carbon electrode formation of gold and so on.

Tao pieces in the cooling process, due to the sharp decline in the temperature of the epidermis part, and the central part of the hardening speed is slower, the formation of thermal stress inside the casting cracks. In order to eliminate this stress, the casting should be annealed to ensure the quality of the fuse.

Annealing is actually to control the hardening and cooling of the casting, there are two ways of annealing, one is the natural annealing - the casting together with the mold into the incubator, so that the natural slow cooling; one is controlled annealing - the epidermis The hardened castings are stripped and placed in a small tunnel kiln and cooled in accordance with the specified annealing curve. The quality of the controllable annealed fuse is superior to that of natural annealing.