Chrome magnesite brick is not used for lining the September 7, 2025 by Admin hearth of soaking pits. bottom hearth of reheating furnace. coke oven regenerator. burning zone of limestone rotary kilns. ✅ The correct answer is option C.
Zircon refractories have September 7, 2025 by Admin low co-efficient of expansion. high RUL (1600°C) and refractoriness (> 2000°C). high spalling resistance. all (a), (b) and (c). ✅ The correct answer is option D.
Which of the following does not occur during firing/burning of refractories ? September 7, 2025 by Admin Removal of water of hydration. Vitrification. Decrease in crushing strength. Development of stable mineral form. ✅ The correct answer is option C.
Periclase refractory contains mainly September 7, 2025 by Admin CaO MgO Al2O3 SiO2 ✅ The correct answer is option B.
Refractory bricks having lower porosity have September 7, 2025 by Admin high insulating properties low heat capacity low thermal conductivity greater strength ✅ The correct answer is option D.
Thoria September 7, 2025 by Admin has high fusion temperature (> 3000°C) but poor resistance to thermal shock. has high resistance to basic slags. which is expensive & radioactive, is used in crucibles for melting high purity metals. all (a), (b) and (c). ✅ The correct answer is option D.
Which is not a natural insulating material? September 7, 2025 by Admin Diatomaceous earth/kieselgur Asbestos Vermiculite None of these ✅ The correct answer is option D.
Segar cones are used for the determination of __________ of refractories. September 7, 2025 by Admin softening temperature spalling resistance electrical conductivity resistance to slag attack ✅ The correct answer is option A.
Magnesite refractories are generally not used in the September 7, 2025 by Admin electric furnace walls. steel melting furnace. open hearth furnace. burning zone of cement kilns. ✅ The correct answer is option B.
Spray test determines the __________ of refractories. September 7, 2025 by Admin resistance to slag penetration resistance to CO attack RUL permanent linear change ✅ The correct answer is option A.