Carbon refractories_____________________?

Related Mcqs:

1. Chromite refractories_____________________?

   A. Are bonded with lime and clay
   B. (Free from silica) have better thermal fatigue resistance than silica and magnesite refractories.
   C. Are resistant to basic slag
   D. All A., B. and C.

2. Carbon refractories are exclusively used in the_________________?

   A. Hearth of blast furnace
   B. Walls of coke oven
   C. Regenerators of coke oven
   D. Side wall of soaking pits

3. Graphite or carbon refractories______________________?

   A. Exhibit wetting characteristics
   B. Should be used in neutral or reducing atmosphere
   C. Exhibit high shrinkage on thermal treatment
   D. Are not resistant to corrosion by slag

4. Carbon refractories have very high __________________?

   A. Wetting characteristics
   B. Refractoriness
   C. Thermal conductivity
   D. Both B. and C.

5. Carbon bricks are not used in the lining of the_________________?

   A. Combustion chamber of blast furnace stoves
   B. Electric furnaces
   C. Highly chemical resistant equipments
   D. Blast furnace hearth

6. ____________ of carbon blocks in the hearth of blast furnace helps in avoiding skull formation, when it becomes cold?

   A. High thermal conductivity
   B. Low porosity
   C. Non-wetting characteristics
   D. High density

7. Carbon refractory blocks ___________________?

   A. Are wetted by molten iron
   B. Are used in the hearth of blast furnace
   C. Are acidic in nature
   D. All A., B. and C.

8. Skull is not formed on the carbon blocks in the hearth of a blast furnace, when it becomes cold, because of its_______________?

   A. Non-wetting characteristic
   B. High thermal conductivity
   C. High crushing strength
   D. None of these

9. Chrome magnesite is not used in the ____________________?

   A. Inner lining of L.D. converter
   B. Aluminium melting furnaces
   C. Wear out lining of steel melting furnaces
   D. All A., and B. and C.

10. Firing of refractory brick is done to __________________?

    A. Dehydrate the dried refractory
    B. Develop stable mineral forms in them
    C. Form ceramic bonds necessary for development of high crushing strength in the finished
    product
    D. All A., B. and C.