Q.1
Resistance to slag attack of a refractory
Q.2
Zircon refractories have
Q.3
Which form of silica has the highest specific gravity?
Q.4
What is Thoria?
Q.5
Zirconia refractory
Q.6
Porosity is induced in insulating refractories by adding
Q.7
A steel member used in the furnace construction to take the thrust of the brickwork is called
Q.8
Pick out the wrong statement.
Q.9
10 to 30% magnesite is added to chromite to produce chrome-magnesite refractories. Magnesite addition is mainly done to improve the __________ of chromite.
Q.10
Which is a basic refractory?
Q.11
Which one expands on heating?
Q.12
Fireclay bricks are never used in the
Q.13
High density refractory bricks have lower
Q.14
Which of the following impurities reduces the refractoriness of magnesite bricks?
Q.15
Silica bricks have low spalling resistance below 600°C, due to its
Q.16
With increase in the density of silica refractories, its
Q.17
Spalling tendency of refractories is reduced by increasing its
Q.18
With increasing alumina content, the fusion point of high alumina refractories
Q.19
Addition of grog in fireclay brick during its manufacture is advantageous, because it results in
Q.20
Tar bonded dolomite bricks
Q.21
With increase in the alumina content, the refractoriness of high alumina refractories
Q.22
Which of the following bricks should not be used, if the furnace is to be used intermit-tantly?
Q.23
Crushing strength of a refractory
Q.24
Sillimanite is a __________ refractory.
Q.25
Silica refractories
Q.26
silicon carbide refractories have very low
Q.27
Fusion temperature of pure silica (SiO₂) is __________ °C.
Q.28
Spray test determines the __________ of refractories.
Q.29
The main raw material for manufacture of silicon carbide refractories is
Q.30
Which is a neutral refractory?
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