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  • Question
  • Silica bricks have low spalling resistance below 600°C, due to its


  • Options
  • A. very high thermal conductivity.
  • B. high co-efficient of expansion upto this temperature.
  • C. high thermal diffusivity.
  • D. low refractoriness.

  • Correct Answer
  • high co-efficient of expansion upto this temperature. 


  • Refractory Technology problems


    Search Results


    • 1. Which of the following bricks has the most close values of RUL and PCE?

    • Options
    • A. Silica bricks
    • B. Fireclay bricks
    • C. High alumina bricks
    • D. Tar dolomite bricks
    • Discuss
    • 2. Chrome magnesite bricks are

    • Options
    • A. acidic in nature.
    • B. neutral in nature.
    • C. having higher RUL than silica bricks.
    • D. made by mixing 30% chromite and 70% periclase.
    • Discuss
    • 3. Because of its very high refractoriness of the order of __________ °C, silicon carbide refractories are used in zinc smelting furnace, muffle furnace and for supporting the wares in tunnel kilns.

    • Options
    • A. 1800
    • B. 2200
    • C. 2400
    • D. 2700
    • Discuss
    • 4. Carbon refractories have very high

    • Options
    • A. wetting characteristics
    • B. refractoriness
    • C. thermal conductivity
    • D. both (b) and (c)
    • Discuss
    • 5. Which furnace consumes maximum refractory annually in an integrated steel plant?

    • Options
    • A. Soaking pit
    • B. Blastfurnace
    • C. L.D. converter
    • D. Coke ovens
    • Discuss
    • 6. Pick out the wrong statement.

    • Options
    • A. Sand & coke is the main raw material for the manufacture of silicon carbide.
    • B. Carbon refractories can not be used in the furnaces operating under reducing conditions.
    • C. Mullite can be obtained by the heating of alusite, kyanite or silimanite.
    • D. Silica occurs in nature in all cellular, amorphous or crystalline form.
    • Discuss
    • 7. Carbon bricks are not used in the lining of the

    • Options
    • A. combustion chamber of blast furnace stoves.
    • B. electric furnaces.
    • C. highly chemical resistant equipments.
    • D. blast furnace hearth.
    • Discuss
    • 8. Silica refractories are not used in

    • Options
    • A. coke oven walls.
    • B. beehive coke ovens.
    • C. dome and upper portion of B.F. stoves.
    • D. open hearth furnace roof.
    • Discuss
    • 9. Which of the following has the lowest electrical resistivity?

    • Options
    • A. Graphite
    • B. Fireclay
    • C. Alumina
    • D. Zircon
    • Discuss
    • 10. Segar cones are used for the determination of __________ of refractories.

    • Options
    • A. softening temperature
    • B. spalling resistance
    • C. electrical conductivity
    • D. resistance to slag attack
    • Discuss


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