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1. How is dissolved oxygen in boiler feed water minimized?

 
 
 
 

2. In a high pressure centrifugal pump the purpose of the diffusion ring is __________.

 
 
 
 

3. How do you make sure that a sample is the true representative of the boiler water to be tested?

 
 
 
 

4. A sample of boiler water can be chemically tested by initially adding a few drops of a specific color indicator, then slowly titrating a standard solution into the water sample until the _____________.

 
 
 
 

5. In what way the radial thrust developed in high pressure centrifugal pump eliminated?

 
 
 
 

6. Which of the following describes a characteristic of scale forming impurities in boiler water?

 
 
 
 

7. Which of the following below is correct about starting a centrifugal pump?

 
 
 
 

8. Which of the following will occur if scale coating effects an increase in tube temperature, causing the strength of the metal to decrease, because they prevent the usual circulation of feed water cooling the tubes and normally carry-off the heat resulting from combustion?

 
 
 
 

9. In what way can the discharge pressure of centrifugal pumps be attained?

 
 
 
 

10. Labyrinth seals used to reduce leakage around a turbine shaft are constructed of __________.

 
 
 
 

11. In main propulsion steam turbine moisture shields is located at the_____________.

 
 
 
 

12. Which type of corrosion is characterized by peeling/splintering of metal into thin, parallel layers?

 
 
 
 

13. Which of the following retard the transfer of heat that longer time will be required to raise steam on the boiler?

 
 
 
 

14. What is the purpose of maintaining an electrical lamp inside the boiler during a dry preservation method?

 
 
 
 

15. When a vessel is to be laid-up in warm climates, why is the boiler sealed-off after it has been generally filled with water, letting it come out from the air vent?

 
 
 
 

16. Which one listed below represent the function the nozzle assembly perform in an impulse turbine?

 
 
 
 

17. What is the function of nozzle diaphragms installed in pressure-compounded impulse turbines?

 
 
 
 

18. In a potable water system which conditions is most likely to cause water hammer?

 
 
 
 

19. Which of the following retard the transfer of heat that longer time will be required to raise steam on the boiler?

 
 
 
 

20. When a vessel is to be laid-up in warm climates, why is the boiler sealed-off after it has been generally filled with water, letting it come out from the air vent?

 
 
 
 

21. For a given size engine, the two-stroke/cycle diesel engine will deliver more power than a four-stroke/cycle diesel engine because__________.

 
 
 
 

22. The thermal energy produced by an internal combustion engine is transformed into __________.

 
 
 
 

23. In a centrifugal pump charging or glazing of the inner circumference of packing rings is caused by;

 
 
 
 

24. Which of the following is a function of lantern rings on the centrifugal pump?

 
 
 
 

25. Which of the following is the purpose of wear rings in a centrifugal pump?

 
 
 
 

26. When handling low viscosity liquids, operating a rotary gear pump far below its rated speed will cause its volumetric efficiency to __________.

 
 
 
 

27. What is the possible cause of a lube oil service pump to have abnormally low pressure?

 
 
 
 

28. Axial-flow and semi-Axial flow rotary pumps are frequently used for large volumes and low heads because they __________. l. Are simple cost; ll. Occupy little space; lll. Are low in capital

 
 
 
 

29. Persistent knocking of one cylinder of a diesel engine ceases when the fuel supply to that cylinder is secured. This problem may be a result of _____________.

 
 
 
 

30. In a proper pump and a centrifugal pump the main difference between them is the absence of a _________.

 
 
 
 

31. To control balance for wear resulting from impeller rotation and abrasions in the liquid handled, a centrifugal pump is usually fitted with:

 
 
 
 

32. A variable speed centrifugal pump will occur:

 
 
 
 

33. Poor combustion in a diesel engine can be caused by __________.

 
 
 
 

34. The purpose of air chamber in a discharge side of an emergency boiler feed steam reciprocating pump is ________.

 
 
 
 

35. If there is cracking noise coming from the centrifugal pump housing, it indicates a/an ________.

 
 
 
 

36. In the operation of gear pump, how does the viscosity of fluid affects?

 
 
 
 

37. Which of the following pumps converts energy (external driving source) into kinetic energy in the fluid by giving impulses to the fluid by impellers?

 
 
 
 

38. A diesel engine should not be operated at low loads for long periods of time because _________.

 
 
 
 

39. The highest pressure in a diesel engine cylinder normally occurs_________.

 
 
 
 

40. A diesel engine indicator diagram has an area of 22 cm2 and a length of 12.5 cm. If the scale of the indicator spring is 1 mm=1 kg/cm2, what is the cylinder mean effective pressure?

 
 
 
 

41. Using a diesel engine indicator P-V diagram, the cylinder mean effective pressure is calculated to be 21.3 kg/cm2. What is the scale of the spring used on the indicator if the diagram area is 18.46 cm2 with a length of 13 cm?

 
 
 
 

42. What is the reason if the pumps fails to deliver liquid?

 
 
 
 

43. The average pressure exerted on a piston during each power stroke is termed ________.

 
 
 
 

44. Which of the following notations does the “N” represent in the formula shown below? IHP=PLAN/(33000)

 
 
 
 

45. The pressure in an operating diesel engine cylinder continues to rise for a short period after the piston passes top dead center as a result of the ________.

 
 
 
 

46. What occurs in the combustion space of a diesel engine cylinder shortly after ignition and before the piston reaches TDC?

 
 
 
 

47. In a large, slow-speed, main propulsion diesel engine, whick of the parts listed is under tension when the engine is running?

 
 
 
 

48. Modern marine diesel engines equipped with mechanical fuel injection operate on a combustion phase within the cycle which is __________.

 
 
 
 

49. The main function of tie rods in the construction of large, low speed diesel engines is to _________.

 
 
 
 

50. What function is provide by the crankcase ventilation system on some diesel engines?

 
 
 
 

51. In a modern internal combustion diesel engine, the load carrying part of the engine is referred to as the _________.

 
 
 
 

52. A safety cover differs from other access doors in that it is fitted with a _________.

 
 
 
 

53. An increase in diesel engine crankcase pressure generally indicates excessive __________.

 
 
 
 

54. In a diesel engine, blow-by ________.

 
 
 
 

55. The purpose of an oil mist detector in a main propulsion diesel engine is to warn of __________.

 
 
 
 

56. In a tank vessel, how often should cargo oil pump relief valve be tested?

 
 
 
 

57. The direct cause of a crankcase explosion can be attributed to ________.

 
 
 
 

58. What is the purpose of removable sleeves on shaft of centrifugal pump?

 
 
 
 

59. Which of the following problems could develop due to the accumulation of oil vapors in the crankcase of a diesel engine?

 
 
 
 

60. The reason for maintaining a minimum flow of liquid to a centrifugal pump use to pump hot liquids under all operating conditions?

 
 
 
 

61. Which of the listed conditions is most likely to cause a crankcase explosion?

 
 
 
 

62. A centrifugal pump is _________.

 
 
 
 

63. Crankcase explosions in propulsion diesel engines result from _______.

 
 
 
 

64. Which of the following bellow affect the discharge rate or capacity of a centrifugal pump?

 
 
 
 

65. Which of the following will increase the capacity of centrifugal pumps? I - Increase the speed; II - Increase the impeller diameter; III - Increase the diameter size of suction pipe

 
 
 
 

66. Which one is considered the basic function of the centrifugal pump impeller?

 
 
 
 

67. If a crankcase explosion occurs in a diesel engine, which of the listed actions should be taken?

 
 
 
 

68. If a diesel engine has been stopped because of piston seizure due to sever overheating, the crankcase _________.

 
 
 
 

69. If water is found in the crankcase of a diesel engine, the cause may be due to _______.

 
 
 
 

70. Main propulsion diesel engines having a bore exceeding 300 mm are to have at least __________.

 
 
 
 

71. Crankcase explosion relief valves should be of the _________.

 
 
 
 

72. Explosion relief valves on diesel engine crankcases should relieve the pressure at not more than _________.

 
 
 
 

73. An important design characteristic of an explosion relief valve for a diesel engine is the ability to ________.

 
 
 
 

74. Cylinder linings constructed as an integral part of the block, are characterized by which of the following disadvantages?

 
 
 
 

75. When inspecting pistons, liners, and rings of a large two-stroke/cycle diesel engine through the cylinder ports, a wet piston crown would indicate a ________.

 
 
 
 

76. The cylinder liner forming the cylinder wall and the insid6e of the water jacket is called a __________.

 
 
 
 

77. The bore of a diesel engine cylinder describes the _________.

 
 
 
 

78. Why are some diesel engine cylinder liners plated on the wearing surface with porous chromium?

 
 
 
 

79. A properly honed diesel engine cylinder liner will _________.

 
 
 
 

80. The lower water seal on a diesel engine wet cylinder liner must allow for liner axial movement. This seal is most commonly a _________.

 
 
 
 

81. Failure to remove the carbon ridge from the top of the cylinder when replacing the piston rings, will result in _________.

 
 
 
 

82. The most severe cavitation erosion occurring on the waterside of diesel engine wet cylinder liners normally occurs __________.

 
 
 
 

83. A crack in a cylinder liner can be caused by _________.

 
 
 
 

84. “Loop,” “uniflow,” “crossflow,” and”return-flow” are terms used to describe various types of _________.

 
 
 
 

85. The difference in the design of closed impeller and open impeller in a centrifugal pump design is _________.

 
 
 
 

86. In what way the closed impellers and open impeller in a centrifugal pump design is __________.

 
 
 
 

87. A centrifugal pump responsible for converting the mechanical energy of the liquid being pumped to kinetic energy is ________.

 
 
 
 

88. The function of wear rings used in centrifugal pump is ___________.

 
 
 

89. Which one of the following components of a centrifugal pump can absorb the wear resulting from impeller rotation and abrasiveness of liquid being pumped?

 
 
 
 

90. The correct explanation on the purpose of wearing ring used for centrifugal pumps is __________.

 
 

91. The main difference between a mechanical seal and a stuffing box gland used in centrifugal pump is __________.

 
 

92. The purpose of lantern ring in centrifugal pumps is ________.

 
 
 
 

93. How do lubricating oil and grease gets into the boiler water system?

 
 
 
 

94. In a centrifugal pump air leakage between the shaft and the stuffing box can be prevented by means of _____________.

 
 
 
 

95. Why is the existence of even a minutely thin film of oil produces exactly the same bad effects as boiler scale?

 
 
 
 

96. Which one are the factors determine the service life of packings on pumps? I - Type of pump; II - The condition of the shaft; III - Length of time in used

 
 
 
 

97. In a centrifugal pump shaft the reason for installing removable sleeve is _____________.

 
 
 
 

98. Which of the following will occur if scale coating effects an increase in tube temperature, causing the strength of the metal to decrease, because they prevent the usual circulation of feed water cooling the tubes and normally carry-off the heat resulting from combustion?

 
 
 
 

99. A component of the centrifugal pump converts the liquid kinetic energy of velocity to potential energy of pressure is___________.

 
 
 
 

100. The primary function of a centrifugal pump volute is __________.

 
 
 
 

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