Function – 6 ( MEP)

 

                                                                 SECTION – 3 

 

1. A grease lubricated ball bearing or roller bearing will run cooler if the grease _____________.

(A)          fills only 10% of all void spaces within the bearing

(B)          has a high grease penetration number

(C)          is thinned with a suitable lubricating oil

(D)          is heated prior to packing the bearing

ANS.: B

4. Why are removable sleeves installed on centrifugal pump shafts?

(A)          They make it easier to replace the pump shaft packing.

(B)          They can be economically replaced as they wear out.

(C)          They can be removed when it is necessary to lighten the weight of the pump.

(D)          They increase the strength of the shaft.

ANS.: B

 

5. If a reciprocating air compressor has a knock occurring in frequency with its operating RPM, the cause is probably ____________.

(A)          misalignment or worn main bearings

(B)          insufficient cylinder lubrication

(C)          defective or poorly fitted valves

(D)          all of the above

ANS.: A

6. Piping is sized by its nominal _________________.

(A)          inside diameter regardless of other parameters

(B)          outside diameter regardless of other parameters

(C)          inside diameter from 3mm to 30cm, and over 30cm by its outside diameter

(D)          inside diameter from 3mm to 60cm, and over 60cm by its outside diameter

ANS.: C

7. Which of the following problems may be encountered by using an oil having a viscosity higher than that specified for an operating hydraulic system?

(A)          External seal leakage.

(B)          Hunting due to fast response.

(C)          Hydraulic oil film breakdown.

(D)          Increased power consumption

ANS.: D

8. Oil emulsification in engine lubricating oils will tend to ________________.
   1. decrease sludge formation in lubricating oil
   2. cause water to separate from the oil
   3. improve the lubricating oil viscosity
   4. displace lubricating oil required in areas of friction.          

ANS.: D

 

9. Lifeboat winches are required to be inspected and an entry made in the logbook. How often is this inspection required to be made?

(A)          Every three months

(B)          Every six months

(C)          Every year

(D)          Only after conducting a boat drill

ANS.: A

11. One cause of leaky valves in a low pressure air compressor may be attributed to _________________.

(A)          running with an air filter element different from that required by the original manufacturer’s specifications

(B)          excessive operating hours without carrying out preventive maintenance

(C)          the compressor running too fast

(D)          excessive discharge pressure

ANS.: B

12. A thermostatic expansion valve is designed to respond to _____________.

(A)          refrigerated space temperature

(B)          compressor suction pressure

(C)          vapor discharge pressure in the cooling coils

(D)          superheat at the outlet of the evaporator coil

ANS.: D

 

10. The color of the refrigeration oil can indicate various operating conditions of the compressor/ refrigeration system in which it is used. Black oil can be an indication of _____________________.

(A)          copper plating caused by moisture in the system

(B)          bearing wear or piston scoring

(C)          carbonization resulting from air in the syste

(d)          gasket breakdown

ANS.: C

 

SECTION – 4 

 

2. Which of the following types of tubes in air compressor coolers would be self-compensating for expansion?
   1. Straight plain tube
   2. U Tube
   3. Coil tube
   4. Floating tube

ANS.: B

3. Which of the following statements is true about compressor air coolers?
   1. Plain tube type coolers have no allowance for expansion
   2. Coil tube type coolers are most easy to clean.
   3. U-tube type coolers are more suitable for lower pressures
   4. Floating tube plate on one end allow for expansion in plain tube type coolers

ANS.: C,D

4. Cavitation erosion occurs due to
   1. Chemical action
   2. Physical action
   3. Chemical OR physical action
   4. Combination of chemical or physical action

ANS.: D

6. You have valves of same bore diameter but of different types. Which of the following is arranged in the decreasing order closing torque required for giving a perfect seal?

 

1. Globe valve, Ball valve, Butterfly valve(rubber seat)
2. Ball valve, Globe valve, Butterfly valve(rubber seat)
3. Butterfly valve(rubber seat), Globe valve, Ball valve
4. Globe valve, Butterfly valve(rubber seat), Ball Valve

ANS.: C

 

7. Metal cladding provides protection to the metal essentially for the life of ship because
   1. During cladding the protective coating reacts chemically with the base metal and inhibits corrosion
   2. This is the only method in which the completeness of the metal coating can assured, while other methods are liable to defects
   3. The thickness of protective coating is greater compared to any other metal coating method used
   4. The adherence of coating is best in case of metal cladding

ANS.: C

8. Many diesel engines have pistons with conceive heads to _______________.
   1. Increase air turbulence and improve fuel mixing
   2. Decrease air turbulence and improve fuel mixing
   3. Prevent fuel after burning when injections ends
   4. Prolong fuel after burning when injection

ANS.: A

‎9. The direction of centrifugal pump depends upon what

1. Vane curvature fromeye to impeller
2. Vane curvature from impeller to eye
3. Direction of volute casing

ANS.: A

9. The direction of centrifugal pump depends upon what
   1. Vane curvature from eye to impeller
   2. Vane curvature from impeller to eye
   3. Direction of volute casing

ANS.: A,C

11. Correct sequence of metals in increasing order of nobility in galvanic series:
    1. zinc,mg,al,steel,
    2. mg,zn,steel,al
    3. al, zn, mg, steel
    4. mg ,zn, al , steel.

ANS.: D

13. Three centrifugal pump are running in parallel and back pressure is increased, flow ratio will reduce
    1. increase in pump casing temperature,
    2. safety alarm,
    3. none,

ANS.: A

14. Cylinder head tightening of auxiliary engineshould always be done in single stage and as per start
    1. tighten sequence two stage and as per manual advised,
    2. tighten sequence single stage and as per manual advised,
    3. tighten sequence as per manual recommended sequence and stage,
    4. none

ANS.: C

15. It is said that strength of steel depends upon carbon percentage, which one of the following steel have max strength
    1. steel with carbon 2%,
    2. steel with carbon 0.8,
    3. steel with carbon 0.32,
    4. pure iron

ANS.: A

16. Which of the following can providegalvanic protection to stainless steel?
    1. copper,
    2. mild steel,
    3. Cupro nickel,
    4. Titanium

ANS.: B

17. Which series is used for determining the suitable electrode for cathodic protection of metal
    1. Fourier ,
    2. Newton,
    3. galvanic,
    4. none

ANS.: C

18. Moisture in a refrigeration system
    1. faulty in expansion valve,
    2. high suction temperature,
    3. high suction pressure,
    4. low discharge temp

ANS.: A

19. Which of the electrical instruments can be used without interrupting a live electrical circuit
    1. megger test,
    2. continuity tester,
    3. current clamp meter,
    4. none

ANS.: C

20. Aluminum bronze alloy
    1. copper, tin, aluminum
    2. copper, aluminum, iron
    3. copper, nickel, aluminum
    4. copper, zinc, aluminum

ANS.: A