MCQ on Boiler

31-Fusible plug for boilers is made of fusible metal containing tin, lead and
(A) Bismuth
(B) Copper
(C) Nickel
(D) Iron
32-Which of the following is not boiler mountings?
(A) Pressure gauge
(B) Feed water check valve (NRV)
(C) Soot blower
(D) Main steam stop valve
33-Primary air is the air used to
(A) Provide air around burners for obtaining optimum combustion
(B) Transport and dry the coal
(C) Convert CO (formed in lower zone of furnace) into CO2 at higher zone
(D) Air-delivered by forced draft fan
34-Hydrogen Sulphide from boiler feed water can be reduced by which of the following process
(A) Deaeration
(B) Coagulation
(C) Aeration
(D) None of the mentioned
35-Tertiary air is the air used to
(A) Provide air around burners for obtaining optimum combustion
(B) Cool the scanners
(C) Supply air for ignitors
(D) Convert CO (formed in lower zone of furnace) into CO₂ at higher zone
36-In pulverized fuel fired large power boiler, the heat transfer from the burning fuel to the walls of furnace is
(A) By conduction only
(B) By convection only
(C) By conduction & convection
(D) Predominantly by radiation
37-The blow down cock in boiler is used for
(A) Regulating drum level by blowing unwanted water
(B) Emptying the boiler in case of shut down
(C) Maintaining constant pressure in drum by blowing unwanted steam
(D) To remove sludge or sediments from drum
38-Ash handling system is not required in
(A) Pulverized coal-fired boiler
(B) Coal gas-fired boiler
(C) Traveling grate-fired boiler
(D) None of the mentioned
39-Which one of the following safety devices is used to protect the boiler when the water level fails below a minimum level?
(A) Water level indicator
(B) Fusible plug
(C) Blow off cock
(D) Safety valve
40-In steam generators, a stokers acts as one of the following devices, what is this device?
(A) Air preheating device
(B) Steam superheating
(C) Air superheating device
(D) Fuel feeding device
41-Re-heaters are used for
(A) Improving efficiency of boiler.
(B) Improving efficiency of turbine.
(C) Improving overall efficiency of the plant.
(D) For supplying dry steam to the turbine
ANSWERS:
31-(A), 32-(C), 33-(B), 34-(C), 35-(D), 36-(C), 37-(D), 38-(B), 39-(B), 40-(D), 41-(C)