Practice Test: Question Set - 25
1. Which of the following boiler is best suited to meet the fluctuating demand of steam?
- (A) Locomotive boiler
- (B) Lancashire boiler
- (C) Cornish boiler
- (D) Babcock and Wilcox boiler
2. In locomotive boiler, maximum steam pressure is limited to
- (A) 1 kg/cm²
- (B) 5 kg/cm²
- (C) 10 kg/cm²
- (D) 18 kg/cm²
3. The fire tubes in a Cochran boiler usually have _________ diameter.
- (A) 6.25 mm
- (B) 62.5 mm
- (C) 72.5 mm
- (D) 92.5 mm
4. Boiler stays are used to
- (A) Prevent flat surfaces under pressure from tearing apart
- (B) Take care of failure in shear
- (C) Take care of failure in compression
- (D) Provide support for boiler
5. Which of the following is required for a steam condensing plant?
- (A) Condenser
- (B) Condensate pump
- (C) Air extraction pump
- (D) All of these
6. Spontaneous combustion is a phenomenon in which
- (A) All the fuel burns instantaneously producing high energy release
- (B) Fuel burns with less air
- (C) Coal bursts into flame without any external ignition source but by itself due to gradual increase in temperature as a result of heat released by combination of oxygen with coal
- (D) Explosion in furnace
7. Fire tube boilers are limited to a maximum working pressure of
- (A) 0.17 MN/m²
- (B) 1.7 MN/m²
- (C) 17 MN/m²
- (D) 170 MN/m²
8. Tertiary air is the air used to
- (A) Provide air around burners for obtaining optimum combustion
- (B) Transport and dry the coal
- (C) Cool the scanners
- (D) Convert CO (formed in lower zone of furnace) into CO₂ at higher zone
9. Desecration of feed water is carried out because it reduces
- (A) Cavitation of boiler feed pumps
- (B) Corrosion caused by oxygen
- (C) Heat transfer coefficient
- (D) pH value of water
10. The function of a safety valve is
- (A) To blow off steam when the pressure of steam inside the boiler exceeds the working pressure
- (B) To indicate the water level inside the boiler to an observer
- (C) To measure pressure of steam inside the steam boiler
- (D) None of the above
11. In a Woolf type compound engine, the high pressure and low pressure cylinders
- (A) Have common piston rod
- (B) Are set at 90°
- (C) Have separate piston rod
- (D) Are set in V arrangement
12. Carbonization of coal is the process of
- (A) Pulverizing coal in inert atmosphere
- (B) Heating wood in a limited supply of air at temperatures below 300°C
- (C) Strongly heating coal continuously for about 48 hours in the absence of air in a closed vessel
- (D) Binding the pulverized coal into briquettes
13. Cut-off ratio is the ratio of
- (A) Swept volume to the volume at cut-off
- (B) Volume at cut-off to the clearance volume
- (C) Volume at cut-off to the swept volume
- (D) Clearance volume to the volume at cut-off
14. The pressure at which latent heat of vaporisation of water is zero, is
- (A) Below atmospheric pressure
- (B) 1 kg/cm²
- (C) 100 kg/cm²
- (D) 225.6 kg/cm²
15. A compound steam engine in which piston rods of high pressure and low pressure cylinders ' are attached to two different cranks set at 180° to each other, is called
- (A) Receiver type compound engine
- (B) Tandem type compound engine
- (C) Woolf type compound engine
- (D) Both (A) and (B)