Le 25 mars 2016, 09:27 dans Humeurs • 0
The checker work of glass furnaces is subjected to more serious corrosion than the crown and sidewall since all checker bricks are subjected to high temperature, duct and alkali vapor. The plugging and collapsing are the main reasons for the shutdown and cold repair of glass furnaces. Therefore, the refractory materials of the checker work should have high mechanical strength, low creep and good resistance to the changes in temperature and atmosphere and alkali corrosion and does not adsorb dust.
In the top part of the checker work, the temperature is high, which can reach up to 1400-1500℃. It is subjected to the most severe erosion by alkali vapor and dust. Rebonded fused magnesia brick is used here. Since rebonded fused magnesia brick contains less silicate phase, periclase crystals are fully developed and are directly bonded, which delays and deters the growing speed of the periclase crystals under the effect of alkali vapor and cracking and pulverizing of bricks.
In the upper part of the checker work, the temperature is 1100-1400℃. Rebonded magnesia brick 95 is used.
In the middle part of the checker work, the temperature is 800-1100℃, within which alkali metal sulfate is condensed and magnesium and calcium checker work severely eroded by Na2O and SO3. It is accompanied with large expansion of bricks and badly damaged. Therefore, the site should not use magnesia brick but direct bonded magnesia chrome brick, magnesia zirconia brick, synthetic magnesia olivine brick and magnesia alumina spinel brick.
In the lower part of the checker work, the temperature is low here and the corrosion is not quite severe. However, it is close to the flue and directly affected by cold air, so it should have good thermal shock resistance and low prices. low porosity fire clay brick is used here.