A. Silicon carbide
B. Magnesite
C. Chromite
D. Graphite
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 - Which of the following is not an acidic refractory?
A. Silica bricks
B. Fireclay bricks
C. Bauxite bricks
D. Magnesia bricks - Which of the following is not a high alumina refractory material ?
A. Kyanite
B. Sillimanite
C. Diaspore
D. Periclase - 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 - 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 - Highest melting (m.p = 3070°C) oxide refractory is__________________?
A. Alumina
B. Thoria
C. Zirconia
D. Magnesia - Thermal conductivity of refractory bricks_________________?
A. Increases with decrease in porosity
B. Decreases with decreases in porosity
C. Is independent of its porosity and is maximum for insulating bricks
D. Increases with the amount of air entrapped in pores
