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  • Question
  • Semi-silica bricks compared to silica bricks have


  • Options
  • A. less fusion point.
  • B. better spalling resistance.
  • C. both (a) and (b).
  • D. neither (a) not (b).

  • Correct Answer
  • both (a) and (b). 


  • Refractory Technology problems


    Search Results


    • 1. Use of higher percentage of lime for bonding silica bricks, reduces their

    • Options
    • A. strength
    • B. abrasion resistance
    • C. both (a) & (b)
    • D. neither (a) nor (b)
    • Discuss
    • 2. Upper portion of hot metal mixer are lined with mullite bricks, which helps in resisting the

    • Options
    • A. washing action of metal.
    • B. corrosion by layer of slag.
    • C. both (a) & (b).
    • D. neither (a) nor (b).
    • Discuss
    • 3. The maximum linear expansion of silica bricks during firing is about __________ percent.

    • Options
    • A. 0.5
    • B. 1
    • C. 2
    • D. 3.5
    • Discuss
    • 4. Dilatometer is used for the determination of __________ of refractories.

    • Options
    • A. modulus of rupture
    • B. permanent linear change
    • C. resistance to CO attack
    • D. RUL
    • Discuss
    • 5. Graphite or carbon refractories

    • Options
    • A. exihibit 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.
    • Discuss
    • 6. Rate of slag attack on refractories increases with rise in temperature due to the

    • Options
    • A. decreased viscosity of slag.
    • B. increased thermal conductivity of brick.
    • C. oxidising condition in the furnace.
    • D. none of these.
    • Discuss
    • 7. Chrome magnesite brick is not used for lining the

    • Options
    • A. hearth of soaking pits.
    • B. bottom hearth of reheating furnace.
    • C. coke oven regenerator.
    • D. burning zone of limestone rotary kilns.
    • Discuss
    • 8. To resist spalling tendency, a refractory should have

    • Options
    • A. greater diffusivity.
    • B. low specific heat.
    • C. low thermal co-efficient of expansion.
    • D. all (a), (b) and (c).
    • Discuss
    • 9. Grog addition in fireclay during brick manufacture is done to

    • Options
    • A. reduce its shrinkage on heating.
    • B. impart greater spalling resistance.
    • C. enhance the strength of fired refractories.
    • D. all (a), (b) and (c).
    • Discuss
    • 10. Roof of a basic open hearth furnace is lined with __________ bricks.

    • Options
    • A. silica
    • B. fireclay
    • C. dolomite
    • D. magnesite
    • Discuss


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