A. Exhibit wetting characteristics
B. Should be used in neutral or reducing atmosphere
C. Exhibit high shrinkage on thermal treatment
D. Are not resistant to corrosion by slag
Related Mcqs:
- Alumina-graphite bricks are used for lining the ____________________?
A. Slide gate in teeming laddies
B. Continuous casting systems
C. Both A. and B.
D. Neither A. nor B. - Carbon refractories are exclusively used in the_________________?
A. Hearth of blast furnace
B. Walls of coke oven
C. Regenerators of coke oven
D. Side wall of soaking pits - Carbon refractories have very high __________________?
A. Wetting characteristics
B. Refractoriness
C. Thermal conductivity
D. Both B. and C. - Carbon bricks are not used in the lining of the_________________?
A. Combustion chamber of blast furnace stoves
B. Electric furnaces
C. Highly chemical resistant equipments
D. Blast furnace hearth - ____________ of carbon blocks in the hearth of blast furnace helps in avoiding skull formation, when it becomes cold?
A. High thermal conductivity
B. Low porosity
C. Non-wetting characteristics
D. High density - Carbon refractory blocks ___________________?
A. Are wetted by molten iron
B. Are used in the hearth of blast furnace
C. Are acidic in nature
D. All A., B. and C. - Carbon refractories_____________________?
A. Do not burn/oxidise, when exposed to air on heating
B. Are not attacked by slags, as they are not wetted by melts
C. Do not resist temperature fluctuations
D. Have extremely low thermal & electrical conductivities - Skull is not formed on the carbon blocks in the hearth of a blast furnace, when it becomes cold, because of its_______________?
A. Non-wetting characteristic
B. High thermal conductivity
C. High crushing strength
D. None of these - Which is the most stable crystalline form of silica at room temperature ?
A. Quartz
B. Cristobalite
C. Tridymite
D. None of these - High alumina refractories are used in the ___________________?
A. Dome of blast furnace stoves
B. Electric arc furnace roof
C. Glass melting furnaces
D. All A., B. and C.
