A. Porosity
B. Specific gravity
C. Thermal conductivity
D. Strength
Related Mcqs:
- Cold crushing strength of refractories depends upon its_________________?
A. Composition
B. Texture
C. Firing temperature
D. All A., B. and C. - To resist spalling tendency, a refractory should have________________?
A. Greater diffusivity
B. Low specific heat
C. Low thermal co-efficient of expansion
D. All A., B. and C. - Faster rate of drying of moulded refractories results in high _____________ of refractories?
A. Green strength
B. Voids
C. Shrinkage
D. Both B. and C. - Spalling of a refractory means its____________________?
A. Softening
B. Fracture due to uneven expansion at high temperature
C. Resistance to compressive loads
D. Resistance to chemical action of gases and molten fluxes - Thermal spalling mainly occurs during _____________ of furnaces?
A. Cooling down
B. Warming up
C. Both A. & B.
D. Neither A. nor B. - With increase in the porosity, thermal spalling resistance of fireclay brick___________________?
A. Increases
B. Decreases
C. Remain same
D. May increase or decrease - Spalling resistance of a refractory cannot be increased by ____________________?
A. Increasing its porosity
B. Using a coarser grog during its manufacture
C. Decreasing its thermal co-efficient of expansion
D. Making it denser - Silica bricks have low spalling resistance below 600°C, due to its________________?
A. Very high thermal conductivity
B. High co-efficient of expansion upto this temperature
C. High thermal diffusivity
D. Low refractoriness - In panel test for spalling resistance, the average face temperature of panel assembly is maintained at ______________ °C for 24 hours?
A. 700
B. 1000
C. 1600
D. 2000 - Pyrometric cone equivalent (PCE) of a refractory is the measure of its_________________?
A. Spalling resistance
B. Fusion point
C. Resistance to slag penetration
D. Resistance to carbon monoxide attack
