61. Hot metal runner in blast furnace are lined with __________ bricks.
silica
carborundum
fireclay
magnesite
✅ The correct answer is option C.
Refractory Technology MCQs
62. Magnesite bricks are used in those parts of furnaces, which are
subjected to temperature fluctuation.
required to resist corrosive basic slag.
subjected to high load.
none of these.
✅ The correct answer is option B.
63. Dolomite bricks have good resistance to attack by
molten steel
iron oxide
lime slag
none of these
✅ The correct answer is option A.
64. Silica bricks are attacked by basic slags at high temperature. Which of the following is not used solely as a binding material?
aluminium phosphate
water
lime
plaster of paris
✅ The correct answer is option B.
65. Thermal diffusivity of a refractory brick is high, when its __________ is high.
density
specific heat
thermal conductivity
none of these
✅ The correct answer is option C.
66. High alumina refractory compared to fireclay bricks have
less load bearing capacity.
less resistance to slag attack.
low refractoriness.
high resistance to thermal shock and creep.
✅ The correct answer is option D.
67. Cold crushing strength of a refractory does not depend upon its
shape
composition
firing temperature
texture
✅ The correct answer is option A.
68. Crushing strength of a refractory
increases with rise in service temperature.
decreases with rise in service temperature.
is unaffected with change in service temperature.
decreases with increase in porosity.
✅ The correct answer is option B.
69. Which is a basic refractory ?
Fireclay
Silica
Chrome magnesite
None of these
✅ The correct answer is option C.
70. Fireclay bricks is not used for lining the
cupola.
gas producer.
bottom of hot metal mixer.
roof of open hearth furnace.
✅ The correct answer is option C.