A. Increases
B. Lowers
C. Does not affect
D. Either A. or B.; depends on its quantity
Related Mcqs:
- Refractoriness/fusion points of ‘Superduty’ refractories is _____________ °C?
A. 1520-1630
B. 1630-1670
C. > 1730
D. > 2000 - Faster rate of drying of moulded refractories results in high ______________ of refractories?
A. Green strength
B. Voids
C. Shrinkage
D. Both B. and C. - With increase in the alumina content, the refractoriness of high alumina refractories_________________?
A. Increases
B. Decreases
C. Remain same
D. May increase or decrease - Pure oxide refractories are generally monocrystalline in nature and are self bonded ______________ bricks are generally used as moderator in nuclear reactors?
A. Beryllia
B. Carborundum
C. Corundum
D. Thoria - Refractories used in/for ______________ should have low thermal conductivity?
A. Coke ovens
B. Insulation
C. Regenerators
D. Muffle furnaces - Panel test determines the ______________ of refractories?
A. Fusion point
B. Spalling resistance
C. Slag penetration resistance
D. Refractoriness under load (RUL) - Magnesite refractories are generally not used in the__________________?
A. Electric furnace walls
B. Steel melting furnace
C. Open hearth furnace
D. Burning zone of cement kilns - Refractories subjected to alternate cycles of heating & cooling are liable to loose their resistance to__________________?
A. Thermal spalling
B. Slag attack
C. Fusion under load
D. CO attack - Chemically, mullite refractories is________________?
A. 3Al2O3.2SiO2
B. Al2O3
C. ZrSO4
D. ThO2 - Magnesite refractories are used for the construction of those furnaces, which are_______________?
A. Not required to resist the corrosive action of basic slag
B. Not subjected to fluctuation in temperature
C. Used for raising & maintaining high temperature
D. Both B. and C.
