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We all know henan refractory brick is a very good fireproof performance, manufacturing process and ordinary brick technology is a big difference, production process is complicated, so that we can in order to better use of refractory brick, we will be very detailed know his characteristics, so what's the detail about using refractory characteristics?

In the production of special refractory bricks, the raw materials, especially the oxide raw materials, are generally prefired (except electric melting raw materials). The purpose of preburning is:

(1) remove volatile impurities, combined water, adsorbed water, carbon dioxide and organic impurities, so as to improve the purity of raw materials.

(2) promote the densification of raw materials, crystallization growth, reduce the burning shrinkage of refractory bricks, or into another stable crystalline phase.

(3) properly control the pre-firing temperature of raw materials to make the particles get surface activation, so as to promote the sintering of the body at a lower temperature.

Pay attention to the temperature of raw material pre-burning. If the preburning temperature is too low, the preburning purpose will not be achieved; if the temperature is too high, the recrystallization will make the crystal grow up and bring difficulties to the sintering of refractory bricks. So the pre-firing temperature depends on the nature of the raw material and the process used. Raw materials can be powder or made into mass prefired.

In the industry, the main equipment commonly used for crushing raw materials are ball mill, vibration mill and airflow mill, etc. There are dry and wet methods for grinding with the first two. Wet method USES water or alcohol as a liquid medium. Wet grinding is suitable for the preparation of fine particles. The grinding efficiency will be higher if dry grinding is used first and then wet grinding. In wet grinding, the liquid medium plays the role of mechanical dispersion, wedge crack and grinding enhancement.