Grog addition in fireclay during brick manufacture is done to_________________?

Related Mcqs:

1. Addition of grog in fireclay brick during its manufacture is advantageous, because it results in_____________________?

   A. Less shrinkage in heating, decreased apparent porosity & increased specific gravity
   B. High strength & thermal spalling resistance
   C. Less addition of water to get a workable plasticity & lesser time required for drying the raw
   refractories and hence increased rate of production
   D. All A., B. and C.

2. Cold crushing strength of ordinary fireclay brick is about 950 kg/cm2. On exposure to a temperature of about 1500°C, its crushing strength may come down to as low as ______________ kg/cm2?

   A. 450
   B. 250
   C. 150
   D. 65

3. Addition of zircon to silica refractory brick improves its_____________________?

   A. Crushing strength
   B. Resistance to slag attack
   C. Both A. and B.
   D. Neither A. nor B.

4. 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.

5. 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

6. Fireclay bricks are not used in the _________________?

   A. Beehive coke oven
   B. By-product coke oven walls
   C. Combustion chamber of B.F. stoves
   D. Coke oven regenerators

7. High alumina refractory compared to fireclay bricks have____________________?

   A. Less load bearing capacity
   B. Less resistance to slag attack
   C. Low refractoriness
   D. High resistance to thermal shock and creep

8. Porosity of fireclay refractories is _______________ percent?

   A. 5-10
   B. 10-25
   C. 25-35
   D. 35-50

9. Fireclay bricks is not used for lining the__________________?

   A. Cupola
   B. Gas producer
   C. Bottom of hot metal mixer
   D. Roof of open hearth furnace

10. Fireclay bricks are not used in the_____________________?

    A. Blast furnace
    B. Hot blast stove
    C. Cupola
    D. Wall of coke oven