Function – 6 ( MEP)

 

SECTION – 2

1. Which of the following V/V cannot be overhauled in place without removing piping?
   1. BallValve
   2. Diaphragm valve
   3. Globe valve
   4. Butterfly valve

ANS.: D

2. When pressure inside a system falls below that of the vapour pressure of the liquid

Cavities r formed, cavities travelling to high pressure region collapses releasing

Considerable energy damage the metal surface which is known as

1. Cavitation
2. Erosion
3. Impingement Corrosion
4. Capitation Erosion

ANS.: A

3. Why should only approved toilet cleaning chemicals be used in
   1. Unapproved chemicals can lead to corrosion in the system
   2. unapproved chemicals can lead to toxic conditions in the system leading
   3. To destruction of protective coatings
   4. Unapproved chemicals can kill aerobic bacteria making the plant ineffective Gases produced by use of unapproved chemicals can pose threat to the operators

ANS.: D

4. After over hauling reciprocal pump the motor connections were wrongly given.

Determine outcome when pump is started?

1. The direction of flow will remain unaffected
2. the direction of flow will b reversed
3. The pump will get damaged because the suction valve will block the reverse flow causing overpressure leading to pump breakdown.
4. The pump will lose suction N there will be no flow.

ANS.: A

 

 

7.Vacuum priming pumps which work on the principle of fixed vane pumps require _____________ for___________ clearance between vane tips and casing.

1. Lube oil, lubricating
2. Lube oil, sealing
3. Water, sealing
4. Gland packing, sealing

 

ANS.: C

 

8.Pump driven clutch type attached vacuum pumps are commonly used for priming ballast pumps and emergency fire pumps. What is the factor which clutches the vacuum pump clutch to the pump clutch during start of the pump?

1. Low suction pressure acting against the spring loaded clutching piston
2. High suction pressure acting against the spring loaded clutching piston
3. Low discharge pressure acting against the spring loaded clutching piston
4. High discharge pressure acting against the spring loaded clutching piston

ANS.: C

 

10.WHICH PROCESS IS NOT DONE ON MILD STEEL?

1. hot plating,
2. electrolysis,
3. explosion bonding,
4. metal spraying

ANS.: C

 

7. Which of the following can be done to reduce the cold corrosion of Main Engine cylinder liners using high sulphur fuel oil :-
   1. Increasing cylinder oil feed rate
   2. Using high TBN cylinder oil
   3. Increasing scavenge air temperature
   4. Decreasing cylinder oil feed rate

ANS.: B

19.It has been reported that Engine room bilge pump was unable to take suction from Fwd. (P) bilge well while it taking suction efficiently from Fwd.(S) & aft bilge wells. What could be the most probable cause?

1. There is leakage in the bilge suction pipeline somewhere between the bilge wells and bilge pump
2. The Fwd. (P) bilge well suction valve might be leaking
3. The Fwd. (P) bilge well suction filter cover gasket might be leaking
4. The pump needs to be overhauled

ANS.: C

 

21. The centrifugal pump normally

A) Positive displacement type

B) Rotodynamic

C) Screw type

D)Gear type

ANS.: B

 

23. The difference between the discharges of a centrifugal pump n reciprocating pump

Thedischarge of centrifugal pump is ———-while that if reciprocating is ———

 

1. Turbulent, Laminar
2.  Intermittent continuous
3. Continuous pulsating
4.  Pulsating continuous

ANS.: C

24. Which of the following is a true statement
    1.  Aluminium will be subject to preferential corrosion when in electrical continuity with stainless steel in presence of an electrolyte.
    2.  Stainless steel will be subject to preferential corrosion when in electrical continuity with mild steel in presence of an electrolyte.
    3.  Copper will be subject to preferential corrosion when in electrical continuity with stainless steel in presence of an electrolyte
    4.  Aluminum will be subject to preferential corrosion when in electrical continuity with zinc in presence of an electrolyte.

ANS.: A

26. The most imp. control measure to prevent boiler tube failure is
    1. Use of proper refractory material.
    2.  Proper maintenance of fuel burning equipment
    3.  Proper maintenance of boiler water condition
    4.  All of the above

ANS.: C

27. When one of the M/E.F.O. heater is not in use then
    1. The F.O. inlet n outlet valve should b kept shut, but steam heating valves should b kept crack open so as to keep the heater warm.
    2. F.O. inlet n outlet valve should be kept shut n heating valves also should be completely shut n should be drained of any remaining F.O.
    3.  F.O. inlet n outlet valve should be kept crack open so that the F.O. recirculation can take place.
    4.  F.O. inlet n outlet valve should be kept shut while outlet valve should be left open so that

ANS.: B

29. It is a known fact that centrifugal pumps require priming for pumping liquids , as they cannot handle air and will lose suction due to air entry . But on the other hand T/Cs use centrifugal compressors for supercharging . Which of the following do you think makes a centrifugal compressors to pump air and behave differently than the centrifugal pumps?
    1. Presence of air cooler
    2. Presence of Labyrinth seal
    3. High speed of rotation , very fine internal clearances and large impeller diameters
    4. Difference in principle of operation

ANS.: C

30. You have a two stage centrifugal pump, with both stages in parallel configuration. After dismantling the pump you realize that you forgot to the marking and both impellers are identical.Both the impellers are single entry type and the eye of both the impellers will come in opposite direction What are you going to do?
    1. Since marking was forgotten, so we need not worry, any impeller can come in any place as they are identical
    2. Any impeller can come in any place, but the phase sequence of the electrical motor driving the pump may have to be reversed, if impellers have exchanged places
    3. You have to find out the right placement of the right impeller with respect to the direction of rotation or by looking at the volute casing
    4. Hit an trial method will have to used to find out the correct placement method by assembling the pump and trying it out

ANS.: C