Panel test determines the ______________ of refractories?

Related Mcqs:

1. In panel test for spalling resistance, the average face temperature of panel assembly is maintained at _____________ °C for 24 hours?

   A. 700
   B. 1000
   C. 1600
   D. 2000

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. Pure oxide refractories are generally monocrystalline in nature and are self bonded ______________ bricks are generally used as moderator in nuclear reactors?

   A. Beryllia
   B. Carborundum
   C. Corundum
   D. Thoria

4. Refractories used in/for ______________ should have low thermal conductivity?

   A. Coke ovens
   B. Insulation
   C. Regenerators
   D. Muffle furnaces

5. Presence of MgO in alumino-silicate refractories ______________ its refractoriness ?

   A. Increases
   B. Lowers
   C. Does not affect
   D. Either A. or B.; depends on its quantity

6. Refractoriness/fusion points of ‘Superduty’ refractories is _____________ °C?

   A. 1520-1630
   B. 1630-1670
   C. > 1730
   D. > 2000

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. Chemically, mullite refractories is________________?

   A. 3Al2O3.2SiO2
   B. Al2O3
   C. ZrSO4
   D. ThO2

9. Magnesite refractories are used for the construction of those furnaces, which are_______________?

   A. Not required to resist the corrosive action of basic slag
   B. Not subjected to fluctuation in temperature
   C. Used for raising & maintaining high temperature
   D. Both B. and C.

10. Which property of refractories is the most important for top section of the blast furnace ?

    A. Resistance to abrasion
    B. Resistance to slag penetration
    C. Stability of volume at high temperature

    D. Resistance to corrosion by slag