IBPS Clerk - Steam Boilers, Engines, Nozzles & Turbines 1000+ MCQ [Solved] PDF Download

1. When the speed of the engine is controlled by means of a valve in a steam pipe, which regulates the pressure of steam entering the engine, then the governing is known as
A. Throttle governing
B. Cut-off governing
C. By-pass governing
D. None of these
Answer : A

2. The ratio of heat utilised to produce steam and the heat liberated in furnace is known as
A. Boiler effectiveness
B. Boiler evaporative capacity
C. Factor of evaporation
D. Boiler efficiency
Answer : D

3. The amount of water evaporated from feed water at _________ into dry and saturated steam at 100° C at normal atmospheric pressure is called equivalent evaporation from and at 100° C.
A. 0°C
B. 40°C
C. 60°C
D. 100°C
Answer : D

4. The heat balance sheet for the boiler shows the
A. Complete account of heat supplied by 1 kg of dry fuel and the heat consumed
B. Moisture present in the fuel
C. Steam formed by combustion of hydrogen per kg of fuel
D. All of the above
Answer : A

5. The working pressure range for a LaMont boiler is
A. 0.5 to 10 MN/m²
B. 1 to 15 MN/m²
C. 2.5 to 15 MN/m²
D. 3.5 to 20 MN/m²
Answer : D

6. Which of the following is a water tube boiler?
A. Locomotive boiler
B. Cochran boiler
C. Cornish boiler
D. Babcock and Wilcox boiler
Answer : D

7. Multi-stage steam turbines are of the
A. Velocity compounded type
B. Reaction type
C. Pressure compounded type
D. All of these
Answer : D

8. The critical pressure ratio for gases is
A. 0.528
B. 0.546
C. 0.577
D. 0.582
Answer : A

9. Which of the following is required for a steam condensing plant?
A. Condenser
B. Condensate pump
C. Air extraction pump
D. All of these
Answer : D

10. Which of the following is correct? (Where p_a = Actual mean effective pressure, p_m = Theoretical mean effective pressure, and K = Diagram factor)
A. p_a = p_m/K
B. p_a = p_m × K
C. p_a = K/p_m
D. p_a = p_m + K
Answer : B

11. The ratio of heat equivalent to brake power to the energy supplied in steam is known as
A. Mechanical efficiency
B. Overall efficiency
C. Indicated thermal efficiency
D. Brake thermal efficiency
Answer : D

12. In a boiler, feed water supplied per hour is 205 kg while coal fired per hour is 23 kg. The net enthalpy rise per kg of water is 145 kJ. If the calorific valve of the coal is 2050 kJ/kg, then the boiler efficiency will be
A. 56 %
B. 63 %
C. 74 %
D. 78 %
Answer : B

13. The safety valve on boiler drum compared to safety valve on superheater is set at
A. Same value
B. Higher value
C. Lower value
D. Lower/higher depending on steam flow
Answer : B

14. All steam engines work on
A. Zeroth law of thermodynamics
B. First law of thermodynamics
C. Second law of thermodynamics
D. None of these
Answer : C

15. Cut-off governing of steam engines is a method of controlling the engine output by varying
A. Volume of intake steam
B. Pressure of intake steam
C. Temperature of intake steam
D. All of these
Answer : A

16. When the cross-section of a nozzle increases continuously from entrance to exit, it is called a
A. Divergent nozzle
B. Convergent nozzle
C. Convergent-divergent nozzle
D. None of these
Answer : A

17. The diameter of fire tube of Cornish boiler compared to its shell is
A. One half
B. One third
C. One fourth
D. One fifth
Answer : A

18. The function of a flywheel is
A. To convert reciprocating motion of the piston into rotary motion
B. To convert rotary motion of the crankshaft into to and fro motion of the valve rod
C. To prevent fluctuation of speed
D. To keep the engine speed uniform at all load conditions
Answer : C

19. The clearance in the engine cylinder
A. Increases the mean effective pressure
B. Increases the workdone
C. Decreases the efficiency of the engine
D. All of these
Answer : D

20. The diagram factor is the ratio of the
A. Area of the actual indicator diagram to the area of theoretical indicator diagram
B. Actual workdone per stroke to the theoretical workdone per stroke
C. Actual mean effective pressure to the theoretical mean effective pressure
D. Any one of the above
Answer : D

21. Which of the following boilers is best suited to meet fluctuating demands?
A. Babcock and Wilcox
B. Locomotive
C. Lancashire
D. Cochran
Answer : B

22. A binary vapour plant consists of
A. Steam turbine
B. Steam condenser
C. Mercury boiler
D. All of these
Answer : D

23. The velocity of whirl at outlet for an axial discharge turbine is
A. Minimum
B. Maximum
C. Zero
D. None of these
Answer : C

24. The steam leaves the nozzle at a
A. High pressure and a low velocity
B. High pressure and a high velocity
C. Low pressure and a low velocity
D. Low pressure and a high velocity
Answer : D

25. Calorific value of coal is of the order of
A. 200-400 kcal/ kg
B. 800-1200 kcal/ kg
C. 2000-4000 kcal/ kg
D. 5000-8000 kcal/ kg
Answer : C

26. The maximum efficiency of a De-Laval turbine is (where ? = Nozzle angle)
A. sin²?
B. cos²?
C. tan²?
D. cot²?
Answer : B

27. The critical pressure at which latent heat of vaporisation is zero is
A. 225.65 kgf/ cm²
B. 273 kgf/ cm²
C. 100 kgf/ cm²
D. 1 kgf/ cm²
Answer : A

28. The effect of super-saturation is that the
A. Mass of the steam discharged increases
B. Entropy and specific volume of the steam increases
C. Exit velocity of steam reduces
D. All of these
Answer : D

29. A stage, in reaction turbine, is represented by
A. Number of casing
B. Number of entries of steam
C. Number of exits of steam
D. Each row of blades
Answer : D

30. The height of chimney in a power plant is governed by
A. The draft to be created
B. Limitation of construction facilities
C. Control of pollution
D. Quantity of flue gases to be handled
Answer : C

31. Feed water conditioning in thermal power plants in done to
A. Reduce hardness and for removal of solids
B. Increase efficiency of thermal power plant
C. Increase heat transfer rate
D. Increase steam parameters
Answer : A

32. The critical pressure gives the velocity of steam at the throat
A. Equal to the velocity of sound
B. Less than the velocity of sound
C. More than the velocity of sound
D. None of these
Answer : A

33. The ratio of the workdone on the blades per kg of steam to the total energy supplied per stage per kg of steam is called
A. Blading efficiency
B. Nozzle efficiency
C. Stage efficiency
D. Mechanical efficiency
Answer : C

34. In a boiler, the heat is lost
A. To dry flue gases
B. In moisture present in the fuel
C. To steam formed by combustion of hydrogen per kg of fuel
D. All of the above
Answer : D

35. Thermal efficiency of well maintained boiler will be of the order
A. 40 %
B. 50 %
C. 75 %
D. 90 %
Answer : D

36. In a Parson's turbine stage, blade velocity is 320 m/s at the mean radius and rotor blade exit angle is 30°. For minimum kinetic energy of the steam leaving the stage, the steam velocity at the exit of the rotor will be
A. 160/3 m/s
B. 320/3 m/s
C. 640/3 m/s
D. 640 m/s
Answer : C

37. In a throttling process
A. Heat transfer takes place
B. Work is done by the expanding steam
C. Internal energy of steam changes
D. None of the above
Answer : D

38. Sulphur in coal results in
A. Corroding air heaters
B. Spontaneous combustion during coal storage
C. Facilitating ash precipitation
D. All of the above
Answer : D

39. The process of maintaining the speed of the turbine constant for various load conditions, is known as
A. Bleeding
B. Reheating
C. Governing
D. None of these
Answer : C

40. 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
Answer : D

41. Which of the following is a fire tube boiler?
A. Lancashire boiler
B. Babcock and Wilcox boiler
C. Yarrow boiler
D. None of these
Answer : A

42. In a reaction turbine when the degree of reaction is zero, then there is
A. No heat drop in moving blades
B. No heat drop in fixed blades
C. Maximum heat drop in moving blades
D. Maximum heat drop in fixed blades
Answer : A

43. In water tube boilers
A. Water passes through the tubes which are surrounded by flames and hot gases
B. The flames and hot gases pass through the tubes which are surrounded by water
C. Forced circulation takes place
D. None of these
Answer : A

44. In case of non-condensing steam engines, the pressure of steam in the cylinder during exhaust stroke is _________ the condenser pressure.
A. Equal to
B. Lower than
C. Higher than
D. None of these
Answer : C

45. In cross compounding, the cylinders are arranged
A. Side by side and each cylinder has common piston, connecting rod and crank
B. Side by side and each cylinder has separate piston, connecting rod and crank
C. At 90° and each cylinder has common piston, connecting rod and crank
D. At 90° and each cylinder has separate piston, connecting rod and crank
Answer : B

46. The water tubes in a simple vertical boiler are
A. Horizontal
B. Vertical
C. Inclined
D. None of these
Answer : C

47. Ultimate analysis of fuel is determination of percentage of
A. Carbon, hydrogen, nitrogen, sulphur, moisture
B. Fixed carbon, ash, volatile matter, moisture
C. Higher calorific value
D. Lower calorific value
Answer : A

48. With increase in load, radiant superheater has
A. Drooping characteristic
B. Linear characteristic
C. Rising characteristic
D. Flat characteristic
Answer : A

49. Which of the following is a fire tube boiler?
A. Locomotive boiler
B. Babcock and Wilcox boiler
C. Stirling boiler
D. All of the above
Answer : A

50. The pressure compounded impulse turbine as compared to velocity compounded turbine require __________ number of stages.
A. Same
B. Less
C. More
D. None of these
Answer : C