Chemically, mullite refractories is____________________?

Related Mcqs:

1. Mullite is chemically represented by_________________?

   A. Al2O3. 2SiO2 B. 3Al2O3. 2SiO2 C. Al2O3. SiO2 D. 2Al2O3. 3SiO2...

2. Faster rate of drying of moulded refractories results in high _____________ of refractories?

   A. Green strength B. Voids C. Shrinkage D. Both B. and C....

3. Upper portion of hot metal mixer are lined with mullite bricks, which helps in resisting the_________________?

   A. Washing action of metal B. Corrosion by layer of slag C. Both A. & B. D. Neither A. nor B....

4. Hot face insulating linings of high purity alumina fused mullite are used, where_________________?

   A. Very high temperatures are involved B. Highly reducing conditions are involved C. Presence of iron or silica is harmful D. All A., B. and C....

5. ‘Spinel’, a refractory mineral is chemically represented as____________________?

   A. MgAl2O4 B. MgAl2O3 C. MgSO4 D. MgAl2O3.2H2O...

6. Si percentage in silica refractories used in the walls of coke oven is about______________________?

   A. 45 B. 60 C. 80 D. 95...

7. Magnesite refractories are generally not used in the___________________?

   A. Electric furnace walls B. Steel melting furnace C. Open hearth furnace D. Burning zone of cement kilns...

8. Cold crushing strength of refractories depends upon its_________________?

   A. Composition B. Texture C. Firing temperature D. All A., B. and C....

9. 10 to 30% magnesite is added to Chromite to produce chrome-magnesite refractories. Magnesite addition is mainly done to improve the _____________ of Chromite?

   A. Spalling resistance B. Refractoriness C. Crushing strength D. Resistance to slag...

10. PCE value (Segar cone) of Superduty refractories is more than 33, which is equivalent to a temperature of ____________ °C?

    A. 1520 B. 1630 C. 1670 D. 1730...