GENERAL ENGINEERING KNOWLEDGE – MEO CLASS 4 MMD PAPER

30. Personnel working with refrigeration systems and subject to the exposure of refrigerants should wear _______________.
    1. face shield
    2. a respirator
    3. rubber gloves
    4. an all purpose gas mask

ANS.: A

31. The ability of a metal to be hammered, or rolled out is called its ___________.
    1. ductibility
    2. elasticity
    3. malleability
    4. fusibility

ANS.: C

32. One characteristic of a lubricating oil adversely affecting the results of centrifuging is ____________.
    1. high TBN value
    2. low oil floc point
    3. low oil demulsibility
    4. low oil neutralization number

ANS.: C

33. Which of the devices listed prevents water from entering a ship’s hull via the propulsion shaft?
    1. Stern tube packing or mechanical shaft seal
    2. Deflector ring and drain
    3. Spring bearings
    4. Oiler rings

ANS.: A

34. With reference to a vessel’s structural integrity, the most significant characteristic of a cryogenic liquid is its ______________.
    1. capability of causing brittle fractures
    2. highly corrosive action on mild steel
    3. vapor cloud which reacts violently with saltwater
    4. toxicity at atmospheric pressure

ANS.: A

35. The heat required to change a substance from a solid to a liquid while at its freezing temperature, is known as the latent heat of _____________.
    1. fusion
    2. vaporization
    3. condensation
    4. sublimation

ANS.: A

36. Which of the following problems occurring in a hydraulic system can be caused by the use of an oil having a viscosity lower than specified?
    1. Seal deterioration
    2. Fast response and hunting
    3. Increase d power consumption
    4. Oil film breakdown

ANS.: C

37. The only means of removing the latent heat of condensation from a refrigerant in the normal refrigeration cycle is by ________.
    1. passing it through the expansion valve
    2. condensing refrigerant in the system condenser
    3. passing the gaseous refrigerant through the heat interchanger on the suction side of the compressor
    4. maintaining a high pressure on the system’s receiver

ANS.: B

38. Which of the following statements represents the main difference between a stuffing box gland and a mechanical seal for sealing the shaft of a centrifugal pump?
    1. Packed stuffing box glands are subject to wear, but mechanical seals are not.
    2. Packed stuffing box glands must be cooled by the liquid being pumped, but mechanical seals do not require cooling.
    3. If packing fails, the pump can be kept running temporarily by tightening the gland, but if a mechanical seal fails it must be totally renewed to stop the leakage.
    4. The sealing surface of a mechanical seal is parallel to the shaft, but the sealing surface of a packed gland is perpendicular to the shaft.

ANS.: C

39. In a shell-and-tube type hydraulic fluid cooler, the amount of heat transferred from the hydraulic fluid to the cooling water depends upon ________________.
    1. the temperature of the hydraulic fluid
    2. the flow rate of both the cooling water and the hydraulic fluid
    3. the temperature of the cooling water
    4. all of the above

ANS.: D

40. The presence of scale and dirt on the saltwater side of lube oil cooler is usually indicated by ___________.
    1. clogged lube oil strainers
    2. seawater leaking into the lube oil system
    3. decreasing lube oil pressure
    4. gradually increasing lube oil temperature

ANS.: D

41. The charging of a refrigerating system should be carried out by adding _____________.
    1. refrigerant vapor to the receiver only
    2. liquid refrigerant to the low side only
    3. liquid refrigerant to the high side only
    4. liquid refrigerant to the high or low side

ANS.: C

42. A leaking suction valve in the second stage of a two stage, high pressure, air compressor can cause excessively high ________________.
    1. second stage discharge pressure
    2. first stage discharge pressure
    3. pressure in the after cooler
    4. compressor final discharge temperature

ANS.: B

43. Fabric type packing, such as flax or hemp, is best suited for _____________.
    1. low temperature use
    2. high temperature use
    3. use where alignment is critical
    4. packing valves with badly grooved stems

ANS.: A

44. Which of the listed problems is occurring if a coil type high pressure evaporator constantly requires an increase in the coil steam pressure in order to maintain capacity?
    1. The brine density is improper.
    2. Heat transfer surfaces are being layered with scale.
    3. Impure distillate is being produced.
    4. Shell vapor pressure is constantly decreasing.

ANS.: B

45. The terms rough, coarse, bastard, second cut, smooth, and dead smooth refer to the ________.
    1. shape of the file
    2. coarseness of the file teeth
    3. size of the file
    4. cuts of the file

ANS.: B

46. A pump is defined as “a device that _____________.”
    1. produces pressure
    2. imparts energy to a fluid to move it from level “A” to level “B”
    3. creates a vacuum to move a liquid in all installations
    4. is to develop a pressure differential

ANS.: B

47. Restrictions occurring in the small orifices of pneumatic control system components can be caused by…………
    1. moisture in the compressed air supply
    2. excessive dryness in the compressed air supply
    3. pressure surging in the compressed air receiver
    4. insufficient lubrication of the system components

ANS.: A

48. The principal purpose of sub cooling liquid refrigerant prior to its entering the expansion valve is to _
    1. increase the refrigerating effect by decreasing the amount of flash gas
    2. allow the refrigerant to enter the throttling device in a saturated condition
    3. increase the refrigerating effect by increasing the amount of flash gas
    4. minimize the temperature drop of the liquid as it passes through the solenoid valve to the outlet side

ANS.: A

49. If a bilge pump is able to develop vacuum, but is unable to sufficiently pump out the bilges, you would check for ________.
    1. the circuit breaker
    2. for leaks in the suction piping
    3. relief valve is not properly seated
    4. the suction strainer

ANS.: D

50. A first stage unloader installed in a low pressure air compressor is unable to completely retract. This will result in ____
    1. overheating of the discharge valve
    2. loss of moisture in the air charge in the receiver
    3. frequent lifting of the intercooler relief valve
    4. an abnormally low intercooler pressure

ANS.: D

51. The heat removed from the refrigerant in the condenser of a refrigeration plant is the
    1. latent heat of expansion
    2. sensible heat of condensation
    3. heat of compression
    4. all of the above

ANS.: C

52. Excessive leakage and premature failure of valve packing is a result of ____________.
    1. opening a valve too quickly
    2. jamming a valve in the closed position
    3. low pressure fluid flow through the pipeline
    4. a scored valve stem

ANS.:D

53. The amount of fuel oil atomized by a return flow oil burner is directly controlled by the
    1. header supply valve
    2. burner root valve
    3. oil micrometer valve
    4. fuel oil back pressure

ANS.: D

54. Fuses are rated in _
    1. voltage
    2. amperage
    3. interrupting capacity
    4. all the above

ANS.: D

55. When there is excessive ingress of water in the engine room onboard causing dangerous levels of bilge water,
    1. Start oily water separator and pump overboard
    2. Start General service pumps and pump bilges overboard
    3. Use bilge injection valve and pump bilges overboard
    4. None of the above

ANS.: 2,3

56. If a radial piston hydraulic pump fails to deliver rated fluid volume, the cause can be _______________.
    1. contaminated fluid
    2. pitted thrust rings
    3. worn pintle bearings
    4. obstructed suctions passage

ANS.: D

57. A fluctuating and unsteady vacuum in an evaporator may be caused by _____________.
    1. wet steam entering the air ejector nozzle
    2. pinhole leaks in the evaporator tube nests
    3. rapid scaling on the evaporator tube nests
    4. high water levels in the last effect

ANS.: A

58. A generator has been exposed to water and is being checked for its safe operation. Therefore, it is necessary to _______________.
    1. check for shorted coils with a explosimeter.
    2. take moisture readings with a hydrometer
    3. test insulation values with a megger
    4. ground the commutator, or slip rings and run it at half load

ANS.: C

59. If the pointer fails to return to zero when a megger is disconnected, the_____________.
    1. pointer is stuck
    2. hair springs are burned out
    3. megger is out of calibration
    4. megger is operating normally

ANS.: D

60. When replacing ball bearings on an electric motor shaft, you should _____________.
    1. tap the outer race with a mallet
    2. apply even pressure to the outer race
    3. apply even force to the inner race
    4. apply pressure evenly to both the inner and outer races

ANS.: C