131. Which is required in an insulating refractory ?
High thermal conductivity
Low porosity
Both (a) and (b)
Neither (a) nor (b)
✅ The correct answer is option D.
Refractory Technology MCQs
132. Fireclay bricks are used in the
furnaces allowed to cool frequently
flues
chimney linings
all (a), (b) and (c)
✅ The correct answer is option D.
133. Fireclay refractories
are not resistant to the action of basic slags.
combine with salts (e.g. chlorides sulphates etc.) & bases (e.g. lime, magnesia etc.) forming fusible aluminates silicates etc.
shrink during firing
all (a), (b) and (c)
✅ The correct answer is option D.
134. Hot blast main (carrying air at 1000°C) in blast furnace are lined with __________ bricks.
silica
fireclay
magnesite
zirconia
✅ The correct answer is option B.
135. Tar dolomite bricks are used in the
basic Bessemer converter
basic open hearth furnace
electric furnaces
all (a), (b) and (c)
✅ The correct answer is option D.
136. Periclase is
crystalline form of MgO.
MgCO3.
ZrSO4.
amorphous magnesite.
✅ The correct answer is option A.
137. Which furnace consumes maximum refractory annually in an integrated steel plant ?
Soaking pit
Blastfurnace
L.D. converter
Coke ovens
✅ The correct answer is option C.
138. Which one contains maximum percentage of Al2O3 ?
Firebrick
Sillimanite
Magnesite
Aluminous firebrick
✅ The correct answer is option B.
139. Fireclay bricks are never used in the
beehive oven
coke oven walls
zinc roaster
lead blast furnace
✅ The correct answer is option B.
140. High porosity refractory bricks have
poor resistance to the peneration of molten slag, metal & flue gases.
poor heat conductivity & low strength.
better thermal spalling resistance.
all (a), (b) and (c).
✅ The correct answer is option D.