111. Maximum shrinkage in volume occurring during burning/firing of dried refractories may be as high as __________ percent.
10
15
20
30
✅ The correct answer is option D.
Refractory Technology MCQs
112. Mixing of ground refractory material and water is done in a __________ mill.
pug
ball
tube
rod
✅ The correct answer is option A.
113. __________ bricks should not be used in oxidising atmosphere.
Tar dolomite
Carbon
Silica
Fireclay
✅ The correct answer is option B.
114. Maximum water percentage in refractory mix meant for hand moulding may be as high as __________ percent.
2-Mar
5-Jul
7-Dec
14-20
✅ The correct answer is option D.
115. Bottom of basic open hearth furnace are constructed of
dead burnt magnesite ramming mass.
porous fireclay bricks.
semi-silica bricks.
silicon carbide bricks.
✅ The correct answer is option A.
116. Grog
contains both alumina and silica.
iscrushed firebrick.
is a non-plastic material.
all (a), (b) and (c).
✅ The correct answer is option D.
117. Which one expands on heating ?
Silica bricks
Fireclay bricks
Both (a) & (b)
Neither (a) nor (b)
✅ The correct answer is option A.
118. __________ of carbon blocks in the hearth of blast furnace helps in avoiding skull formation, when it becomes cold.
High thermal conductivity
Low porosity
Non-wetting characteristics
High density
✅ The correct answer is option C.
119. Silicon carbide refractories are used in the
muffle furnace
zinc smelting furnace
ceramic recuperators
all (a), (b) and (c)
✅ The correct answer is option D.
120. RUL of refractories depends on the
chemical composition.
physical structure.
presence of impurities like iron & alkali.
all (a), (b) and (c).
✅ The correct answer is option D.