A. Speed of the fan
B. Damper
C. Variation in the pitch of fan blades
D. All A., B. and C.
Related Mcqs:
- Power required in case of forced draught as compared to induced draught (for the same draught produced) is___________________?
A. Same
B. Less
C. More
D. Either more or less; depends on the flue gas density - Which furnace employs an I.D. fan for the removal of flue gases from the furnace ?
A. Coke oven
B. Blast furnace stoves
C. Beehive coke oven
D. High pressure boiler - Combustion of furnace oil in a furnace (soaking pit) with preheated combustion air at 400°C results in saving of about __________ percent furnace oil as compared to its combustion with atmospheric air, if the flue gas outlet temperature from the soaking pit is 1200°C ?
A. 5
B. 60
C. 20
D. 40 - The electric furnace in which heat is produced by a combination of induced current and skin effect is called _____________ furnace?
A. Arc
B. Resistance
C. Low frequency induction
D. High frequency induction - In a furnace employing forced draught as compared to induced draught______________________?
A. Air is sucked in, so air leaks are more and hence the furnace efficiency is reduced
B. The fan operates hot and hence blades are liable to corrosion and erosion
C. Positive pressure exists in the furnace
D. None of these - Which one is not an induced draught furnace ?
A. Blast furnace stove
B. Sintering furnace
C. High pressure boiler
D. None of these - Furnace pressure is normally controlled by regulating the__________________?
A. Air pressure
B. Fuel gas pressure
C. Speed of I.D. fan
D. Damper - In a furnace, the heat taken by the charge/stock and the heat lost to the furnace structure & flue gases depends on the__________________?
A. Rate of firing and emissivity of flame
B. Thermal conductivity of the charge & structural materials of furnace
C. Nature of process; whether batch, continuous or intermittent
D. All A., B. and C. - Ceramic coating material for furnace refractory, which increases its emissivity and thus the radiation heat transfer rate in the furnace, comprises of_________________?
A. Graphite powder
B. Thoria
C. Zircon powder
D. Beryllium - _____________ furnace is not an electric furnace?
A. Arc
B. Induction
C. Pot
D. Resistance
