A. Basic
B. Neutral
C. High alumina
D. Insulating
Related Mcqs:
- Sillimanite (Al2O3.SiO2) refractory, which is a neutral refractory, is not used in________________?
A. Pottery furnace
B. Glass melting furnace
C. Crucibles
D. Gas retorts - Maximum water percentage in refractory mix meant for hand moulding may be as high as _____________ percent?
A. 2-3
B. 5-7
C. 7-12
D. 14-20 - _____________ is not a single oxide-refractory?
A. Zirconia
B. Silicon carbide
C. Magnesia
D. None of these - Maximum alumina content in high alumina refractory can be as high as _____________ percent?
A. 30
B. 50
C. 70
D. 90 - High thermal conductivity of a refractory material is not important, when it is to be used in the______________________?
A. Coke oven regenerators
B. Muffle furnace
C. Blast furnace
D. Recuperators - Test piece for determination of RUL of a refractory is heated in a/an____________________?
A. Oxidising atmosphere
B. Reducing atmosphere
C. Electric furnace
D. Neutral atmosphere - 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. - 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 - Which is not a high alumina refractory ?
A. Mullite
B. Corundum
C. Bauxite
D. Dolomite - Refractory bricks with lower permeability is produced by using __________________?
A. Higher firing temperature
B. Higher moulding pressure
C. Finer grog size
D. All A., B. and C.
