22. After cleaning the sea chest filter you have placed the filter in the body and tightened the cover. Which one of the following is the best alternative?
- You can open the filter inlet and outlet valves & directly start using the filter
- If you do not want to use the sea chest in question, you need not worry and you can open the valves when required
- Sea Water inlet valve should be crack opened, the filter body should be purged, any leakages and thereafter filter can be kept isolated or used as required
- You will close the other side sea chest valves first and then open this side sea chest filter inlet and outlet valves
23. In which of the following types of refractory failure, softening of the refractory bricks takes place due to presence of sodium/vanadium in fuel?
C. Shrinkage cracking
24. centrifugal pump will typically give you a low flow rate at a lower pressure, where a piston pump will give you more pressure and higher flow rate. Is the statement correct?
- First Sentence is right. Second one is wrong
- I don’t know
- You are pumping out sludge to a shore facility using your sludge pump. You find that the discharge rate of pump is very slow and suction filter is getting clogged frequently. What is the best alternative to counteract the problem
- A. Remove the pump suction filter and pump out the tank
- B. Increase the tank temperature, keep an eye on the pump suction pressure and clean the filter as soon as it drops
- C. As soon as the as the shore facility tells you that they are not receiving any sludge, you stop the pump and clean the filter
- D. Fabricate a bigger mesh size suction filter and use in place of normal filter so that frequency of filter blockage is reduced and you can get a better discharge rate
26. Pump Start but Motor get overloaded or Trip on overload.
1. Alignment is wrong
2. Gland packing too tight
3. Worn out / Damaged ball bearing
4. Cavitations exists
5. All of the above
27. A ball valve is found leaking in service and needs to be overhauled. What type of repairs can be carried out?
a. The ball and seat can be lapped together
b. The ball can be machined while the seat can be replaced
c. Normally both the non-metallic seats get worn out and have to be replaced
d. Normally ball gets damaged and has to be replaced
28. The difference between the discharges of a centrifugal pump n reciprocating pump
the discharge of centrifugal pump is ———-while that if reciprocating is ———
A) Turbulent, Laminar
B) Intermittent, continuous
C) Continuous, pulsating
D) Pulsating, continuous
29. Purifier is not rotating with desired rpm, reason?
- Frequency low
- Bus bar voltage low
- Friction pads worn out
30. The function of an accumulator on the discharge side of a reciprocating bilge pump is to:
A. Supply liquid even when the pump is not running
B. Dampen out the pressure pulses and smoothen the flow
C. Increase the discharge pressure by storing liquid under pressure
D. No such device is required to be fitted to modern bilge pumps
31. The most important control measure to prevent boiler tube failure is:
A. Use of proper refractory material
B. Proper maintenance of fuel burning equipment
C. Proper maintenance of boiler water condition
D. All of the above
32. Refer cooling tubes act as self-cooling & expansion by
a) Straight tube
b) U tube
c) Spring tube
33. F.O. transfer pump was working efficiently, but it stopped taking suction suddenly. There is a sounding of 6.0 m in the F.O. deep tank. The suction pressure gauge was renewed recently and is showing a positive pressure when pump is running, but Pump is not transferring any F.O. What is the most probable cause?
- Pump is damaged and needs overhaul
- Suction filter cover gasket might leaking
- Pump relief valve might be leaking
- The pump suction pipeline is blocked
34. A ball valve was found leaking in service. Upon inspection it was found that the PTFE seat had worn out and was renewed. The valve stopped leaking in closed condition. How do think a ball valve provides perfect sealing?
A. The seat fitted is slightly smaller than the outer dimensions of the ball, thus providing interference fit when closed
B. Either a floating seat is pressed onto trunnion supported ball by liquid pressure or floating ball is pressed onto the seat
C. Ball is not exactly spherical and is shaped such that during closure the surface coming into contact with seat is of slightly bigger diameter providing sealing
D. Seat is not exactly spherical, but slightly tapered so that during closure the ball sits tightly on the seat
35. Copper tubing is used in refrigerant system because……..
A) It has less internal resistance
B) It is cheaper compared to other materials.
C) It is easier to check leaks in copper based system
D)None of the above
36. You are responsible for daily transfers of engine room bilges. You follow the sequences aft –fwd (P)-fwd(s) bilge well n u have never experienced a problem but 5/E started the transfer n first transferred forward (s) bilge well n without any problem n u join him later u find that bilge pump is not taking suction fr f(p) n aft bilge well n then u have checked everything is normal. What is the cause?
- 5th engineer made a mistake by 1st transferring the fwd (s) bilge well, normal sequence of operation for engine room machineries should not b disturbed.
- Fwd (s) Bilge well suction valve is leaking
- Bilge pump suction filter cover gasket is leaking.
- Fwd (s) Bilge well suction filter cover gasket is leaking.
37. The gland packing of centrifugal pump should ,……
A) Not allow any breakage under the suction pressure.
B) only allow drop by drop continuous leakage under positive suction pressure.
C) Should allow considerable leakage
38. Which of the following valve is liable to open or close under pressure of fluid, if not locked in position?
- Gate valve
- Globe valve
- Plug valve
- Butterfly valve
39. If dew point increases what happens to wet bulb temp and dry bulb temp? (Fill in the blanks)
ANS.: Will be same
40. The dew point is reached when the wet bulb temperature is _____________
ANS.: Equal to the dry bulb temperature
41. As the amount of moisture in the air increases, the difference between the dry bulb and wet bulb temperatures will…………..