crushing strength
resistance to slag attack
both (a) and (b)
neither (a) nor (b)
✅ The correct answer is option B.
Refractory Technology MCQs
With increase in the alumina content in firebricks, its fusion point (refractoriness)
decreases linearly
remains unchanged
increases
decreases
✅ The correct answer is option C.
Pure oxide refractories are generally monocrystaliine in nature and are self bonded __________ bricks are generally used as moderator in nuclear reactors.
Beryllia
Carborundum
Corundum
Thoria
✅ The correct answer is option A.
Except __________ , all other refractories are bad conductors of electricity (i.e, have low electrical conductivity).
fireclay
carborundum
graphite
chromite
✅ The correct answer is option C.
An ideal refractory should have high
spalling rate
fusion point
shrinkage ability
none of these
✅ The correct answer is option B.
Which of the following bricks has the most close values of RUL and PCE ?
Silica bricks
Fireclay bricks
High alumina bricks
Tar dolomite bricks
✅ The correct answer is option A.
Which is the stable form of silica upto 1470°C ?
Quartz
Cristobalite
Tridymite
None of these
✅ The correct answer is option C.
The highest melting pure oxide (m.p. > 3000°C)is
thoria
alumina
beryllia
zirconia
✅ The correct answer is option A.
Refractories are dried in the
rotary kilns
tunnel kilns
sun
none of these
✅ The correct answer is option B.
Carbon refractories
do not burn/oxidise, when exposed to air on heating.
are not attacked by slags, as they are not wetted by melts.
do not resist temperature fluctuations.
have extremely low thermal & electrical conductivities.
✅ The correct answer is option B.