1, clay brick (insulation brick): used in the area of preheating forging belt, refractoriness under SK35
2, high aluminum brick: its main component is Al203, the higher the content, the higher the refractories of refractory bricks, the resistance to peeling, thermal conductivity, mechanical strength, chemical erosion resistance are better. However, the high alumina brick has great reversible expansion, and the slag resistance is worse than the salt base fire brick. Generally used in the forged belt (transition belt). The commonly used fire resistance index is SK37. Use SK37 or 36 in the cooling zone.
3. Alkaline firebrick: alkaline firebrick has high chemical resistance to ash and dissolved slag at high temperature, has good performance of hanging kiln skin, and the adhesion ratio of kiln skin is firm. Because the brick and the kiln skin are dissolved as one, if the kiln skin falls off, some of the kiln bricks will also fall with the kiln skin, and the resistance to peeling is higher. It mainly has two kinds of bricks:
3.1, Dolomite brick (Dolomite), the main component of dolomite brick is magnesite (Mg0), its composition and raw material composition is relatively close, so this brick hanging kiln skin performance is better, will not react with the material. It has high fire resistance and volume stability, but when the kiln skin falls, a part of the kiln brick may also fall together with the kiln skin. Pay attention to the anti-ashing effect when using. Kiln bricks should pay special attention to waterproof when adjusting storage.
3.2, magnesia chrome brick: the main component of magnesia chrome brick is chromium ore. It has good spalling resistance and mechanical strength. It is generally used in the firing belt of rotary kilns. In the firing zone, it is damaged by three conditions: thermal stress, mechanical stress and chemical erosion. Therefore, the kiln brick requirements of this belt are relatively strict. In the past, chrome-magnesium bricks were generally used, which have the advantages of high refractoriness and good resistance to alkaline chemical erosion. However, the chromium content of magnesia-chromium brick components is relatively high, and when the fire brick is abandoned, the chromium metal will be lost together with water and enter the environment causing pollution. At present, the amount of chrome-magnesia brick is gradually reduced, and has been replaced by spinel brick.