lime
basic
acid
none of these
✅ The correct answer is option C.
Refractory Technology MCQs
Thermal conductivity of refractory bricks
increases with decrease in porosity.
decreases with decreases in porosity.
is independent of its porosity and is maximum for insulating bricks.
increases with the amount of air entrapped in pores.
✅ The correct answer is option A.
__________ nozzles are used in continuous casting of steel,
Zircon
Thoria
Carborundum
Beryllia
✅ The correct answer is option A.
Chrome magnesite bricks are used in the
side walls of soaking pits and arc furnaces.
copper melting furnaces & converters.
burner block of glass tanks.
all (a), (b) and (c)
✅ The correct answer is option D.
With increase in the porosity, thermal spalling resistance of fireclay brick
increases
decreases
remains same
may increase or decrease
✅ The correct answer is option A.
Zircon refractories have
low co-efficient of expansion.
high RUL (1600°C) and refractoriness (> 2000°C).
high spalling resistance.
all (a), (b) and (c).
✅ The correct answer is option D.
Which is an acidic refractory ?
Magnesite
Dolomite
Fireclay
Chrome magnesite
✅ The correct answer is option C.
Segar cones are used for the determination of __________ of refractories.
softening temperature
spalling resistance
electrical conductivity
resistance to slag attack
✅ The correct answer is option A.
Silliminite (Al2O3.SiO2) refractory, which is a neutral refractory, is not used in
pottery furnace
glass melting furnace
crucibles
gas retorts
✅ The correct answer is option D.
Which is not a high alumina refractory ?
Mullite
Corrundum
Bauxite
Dolomite
✅ The correct answer is option D.