latihan soal pasca prala att 3 Maintance and repair of shipboard machinery and equipment

Maintance and repair of shipboard machinery and equipment

1. A threaded hole is to be formed in a steel plate using a tap and wrench. When drilling the hole which of the options
   best describes the required drill size?

1. The drill should be the same size as the diameter of the tap

2. The drill should be a bigger size than the diameter of the tap

3. The drill should be the same size at the diameter of the bolt that is to be fitted into the hole

4. The drill should be a smaller size than the diameter of the tap

5. IDon't Know

2. While getting tools ready and preparing for overhaul work on the main engine the engine room rating notices that the
   electrical extension is damaged. A small section of the cables outer insulation is split although the inner insulation
   appears ok. What action should the rating take?

1. Carry on using the extension after wrapping insulation tape over the damaged section as it is only minor
   damage

2. Just use the extension as it is since the damage is only to the outer insulation and the inner insulation appears ok

3. Cut off the end of the cable including the damaged section and refit the plug to the end of the remaining cable before using the extension

4. Label the damaged extension as unfit for use and return it to the store for testing and get a replacement extension

5. I Don't Know

3. What is the correct method to use for fitting a rolling contact bearing, such as a ball bearing, onto a parallel shaft?

1. Use emery cloth on the inner ring (contact surface) of the bearing.

2. Gently heat the bearing in an oil bath and use a bearing puller to draw it onto the shaft.

3. Use a hammer and a pipe with the same diameter as the inner bearing ring and knock the bearing onto the
   shaft

4. Use emery cloth on the bearing surface on the shaft

5. I Don't Know.

4. What is the most suitable type of packing for a shaft gland of a pump used for seawater duties?

1. Mica impregnated cotton packing

2. Greasy cotton packing

3. Lead covered hemp packing

4. PTFE rope packing

5. IDon't Know.

5. If inspection or repair of the boiler is due, the plant has to be shut down, and the boiler emptied for water. If time is
   available, which of the following procedures is correct?

1. The boiler should be blown down to sea immediately after shut down.

2. The boiler should be allowed to cool down after shut down and then the water should be drained out.

3. The safety valve easing gear be operated and all the pressure released immediately after shut down and then
   the remaining water is drained.

4. The feed water regulator should be bypassed and the boiler topped up with cold feed water immediately after shut down to help cool it down before draining.

5. I Don't Know.

6. A seawater pipe is holed due to corrosion causing frequent bilge alarms. Which of the given temporary repair
   methods would be the preferred option to remedy the problem until the pipe can be replaced?

1. Cover all of the affected area with fibre glass tape and resin/fibre glass mixture

2. Drive a steel taper pin into the hole to seal it

3. Cover the hole with rubber insertion held in place with a jubilee clip

4. Drive a steel taper pin into the hole to seal it

5. I Don't Know.

7. During overhaul of some plate type compressor valves the engine room rating is asked to clean the valve plates and
   seat. Some of the valve plates are heavily marked. What action should be taken?

1. Dress the valve plates up using a portable grinder

2. Use coarse grinding paste to remove the marks from the valve plates as quickly as possible

3. Discard the defective valve plates and replace them with new spares

4. Skim the valve plates in the lathe to remove all of the marks

5. IDon't Know.

8. A spare cylinder head for the generator needs to be lifted from its storage cradle to the generator fiat. Because of its
   location the engine room crane cannot be positioned directly above it. What method should be used to bring the
   cylinder head into position?

1. Use crow bars to lever the cylinder cover across the deck until it is in position below the crane

2. Attach the crane hook to the lifting gear for the cylinder head and drag it across the deck until it is directly under the crane

3. Rig chain blocks to lift the cylinder head from its cradle and then transfer it gradually over to the crane hook by working the chain blocks

4. Use a block and tackle to drag the head across to a position beneath the crane

5. I Don't Know

9. During overhaul of a purifier the engine room rating is instructed to drain and clean the gearbox on the machine.
   Which of the materials given in the options is the best one for wiping up the remaining oil in the gearbox after
   draining the oil?

1. Used paper towels from the wash room

2. Used dish cloths from the galley

3. Clean, lint free cotton rags

4. Clean cotton waste

5. I Don't Know

10. On some large slow speed engines the crosshead guides are adjustable to allow the clearance between the
    crosshead shoes and the guides to be set equally. The normal arrangement is to have bolted on guide bars with
    shims fitted behind them. Which of the methods given in the options is the one normally used to ensure this is done
    correctly?

1. Turn the engine so that the piston skirt is at the bottom of the liner. Use wedges to centralise the piston. Measure the clearances along the length of each bar and shoe and fit shims to equalise the clearances

2. Turn the engine so that the piston for the cylinder concerned is at TDC and measure the clearance along the length of each bar and shoe and fit shims to equalise the clearances.

3. Fit an equal number of shims behind each guide bar which should result in equal clearances between the guide bars and shoes along the whole length.

4. Turn the engine so that the piston for the cylinder concerned is at BDC and measure the clearance along the length of each bar and shoe and fit shims to equalise the clearances.

5. IDon't Know

11. What would be considered to be the normal service life for rolling contact bearings fitted to a large turbocharger for a
    diesel engine?

1. 8000 12000 hours.

2. 1000 3000hours.

3. 20000.-25000 hours.

4. At least 30000 hours.

5. I Don't Know

12. When checking the closed butt gap clearance of new piston rings prior to fitting onto the piston it is normal to try the rings in the liner so that the gap can be measured. From the options given select the best part of the liner to use to
    carry out these checks.

1. Just above the scavenge ports.

2. Near the top of the liner.

3. Near the bottom of the liner.

4. Near mid-height of the liner.

5. IDon't Know

13. Which one of the statements given in the options is correct in relation to the maintenance and adjustment of 4-
    stroke, medium speed diesel engines?

1. Both the top and bottom shells of a bottom end bearing should be inspected as they can wear due to load reversal during the engine operating cycle

2. Liner wear of up to 3% of the bore size is generally acceptable for continued service.

3. The piston ring groove clearances for the oil control ring are unimportant as this ring does not form part of the gas seal.

4. Timing of inlet and exhaust valves can be correctly set by varying the tappet clearance.

5.  I Don't Know.

14. An electric motor is to be aligned to a pump by inserting shims under the motor feet. Which tool would be used to check that the alignment is correct by measurement of the gap between the coupling faces?

1. An inside micrometer

2. An inside vernier calliper

3. A go/no go gauge

4. A set of feeler gauges

5. I Don't Know

15. The holding down arrangement for a large 2-stroke diesel engine consists of steel chocks and hydraulically tightened holding down bolts. When carrying out routine maintenance of the arrangement which method, from those given in the options, should be adopted to check that it is in good order

1. Tap the holding down bolts with a hammer to see if they 'ring'

2. .Tap the steel chocks with a hammer to see if they move.

3. Check the hydraulic release pressure for the holding down bolts.

4. Measure the length of the holding down bolts to make sure they have the correct extension for the recommended tension

5. I Don't Know

16. Welding and burning are two operations which give the highest risk of a fire on board ship. Which of the following
    safety precautions may be regarded as the most important in order to minimise this particular risk?

1. Only use electrodes from a well known manufacturer

2. Only holders of a welding certificate should be allowed to carry out welding or burning on board ships

3. The area where the welding is to take place and adjacent spaces to be cleaned and all unnecessary materials and objects to be removed

4. Electric welding plants should be controlled by a responsible engineer before use

5. I Don't Know

17. When working at height onboard ships what is the most important safety precaution that should be taken?

1. Lash the bottom of the ladder to a fixed point

2. Wear a safety harness securely attached to ship's structure

3. Keep all the tools required for the work in a bucket

4. Wear a safety helmet and goggles

5. I Don't Know.

18. A small electric motor needs to be taken to the bottom plates for fitting to a domestic water pump. It is only just too heavy to be manually carried so is to be lowered using the engine room crane. Which of the options given would be
    a suitable strop to use for the operation?

1. Any strop which looks big enough to carry the load

2. Any certified strop which has a safe working load greater than the weight of the motor

3. Any piece of rope will do as the motor is only just too heavy to carry

4. A wire strop which is rated for twice the required load but is out of certification

5. I Don't Know

19. Most maintenance and repair tasks carried out onboard ship require a permit to work which will include a full risk assessment. Where would an engine room rating fid out about the precautions that are required for a particular
    task?

1. Chief Engineer's standing orders

2. Engine room log book

3. Ships Safety Management Manual (ISM Code procedures)

4. Code of Safe Working Practices (COSWP)

5. I Don't KnoW.

20. How is damage to the piston rod stuffing box rings avoided when removing and replacing the piston during overhaul
    piston of a large two stroke diesel engine?

1. The piston rod gland should always be removed from the engine before the piston is lifted out to avoid damage
   to the rings.

2. The lower part of the piston rod is wrapped in rags.

3. The piston rod nut is put on during removal and refitting of the piston through the gland.

4. A tapered guide sleeve should be fitted over the threaded end of the piston rod.

5. I Don't Know.

21. Which tool would be used to produce accurately sized bolt holes in a steel flange?

1. A hole punch

2. A twist drill

3. A centre drill

4. A reamer

5. I Don't Know

22. Which type of pump is shown in the illustration?

1. A scroll pump

2. A reciprocating pump

3. A gear pump

4. I Don’t Know

23. A pump cover is sealed using a paper gasket which is damaged during overhaul. There are no spare gaskets
    available. How should the casing be sealed when reassembling the pump?

1. Make a new gasket from old chart paper or other similar material of the same thickness as the original gasket

2. Put a thick layer of jointing compound on the face of the cover and tighten the cover until the compound squeezes out

3. Re-use the old gasket

4. Run a bead of silicon around the outside of the joint after fitting the cover

5. I Don't Know.

24. What would be the likely cause if the shaft of a centrifugal pump shows excessive wear in way of the stuffing box?

1. Over tightening of the gland packing

2. Incorrect material used in construction of the shaft

3. The discharge pressure of the pump is too high

4. Wrong direction of rotation of the pump

5. I Don't Know

25. Many medium and high speed marine diesel engines have connecting rods with an obliquely (angled) split in way of the bottom end which may have serrated faces. What is the main reason that the connecting rods are manufactured with this oblique split?

1. It reduces the inertial loads generated during operation as the connecting rod can be made lighter.

2. It allows larger bottom end bolts to be used without risk of fouling the bottom of the oil pan.

3. It allows the bottom end bearing to be large but still allows the piston to be withdrawn from the top of the cylinder

4. It gives better access to the bottom end bolts.

5. I Don't Know

26. What is meant by the term 'lapping in' in relation to diesel engine cylinder cover valves?

1. Machining the valve and seat to achieve a differential seat angle

2. Grinding the valve against the valve seat, usually manually, to obtain a uniform sealing surface across the seat

3. Repair of the valve by welding stellite onto the seat

4. The period of overlap when the inlet and exhaust valves for a cylinder are open together

5. IDon't Know.

27. Modern medium speed diesel engines normally have relatively short crankshafts with large diameter pins. How do these design features affect the reliability of crankshaft deflection readings?

1. The design of the crankshaft has very little effect on the readings when compared to the inaccuracies that arise due to human error.

2. Very short, stiff crankshafts do not deflect even when the engine is running so the readings are unaffected.

3. They reduce the risk of inaccurate readings as the large diameter pins result in a relatively heavy shaft which will reduce the risk of floating journals

4. They increase the risk of inaccurate readings due to the 'stiff shaft having very small natural sag which may therefore result in floating journals' in the static condition.

5. I Don't Know

28. When refitting the bolts into a flange on a steam line how should the bolts be prepared so that they can be easily removed next time maintenance is required?

1. Coat the threads in graphite based grease

2. Apply thread tape to the bolt threads

3. Coat the threads in graphite based grease

4. Fit the bolts dry with a spring washer

5. I Don't Know.

29. During maintenance work on a fuel tank the engine room ratings are removing scale in preparation for re-coating One of the ratings suddenly notices the smell of fumes even though the atmosphere had been satisfactorily tested
    before the work started. What action should the ratings take?

1. Ask for another fan to be switched on to increase the ventilation in the tank

2. Leave the tank immediately and have the atmosphere retested

3. Stop work until the smell disappears and then carry on removing the scale
   Put on breathing apparatus and carry on with the task

4. I Don't Know.

30. Which tool would be best suited for cutting a piece of angle iron?

1. Tenon saw

2. Rip saw

3. Crosscut saw

4. Hacksaw

5. IDon't Know.

31. During maintenance of a piston rod stuffing box on a large, slow speed diesel engine it is usual to measure the butt gaps between the sealing ring and scraper ring segments. What would be the effect of these gaps being too small?

1. If the gaps are too small the rings could score the piston rod

2. If the gaps were too small then no oil could pass up the piston rod to lubricate the sealing rings,

3.  If the gaps are too small then the flow of scavenge air through the gland would be reduced and the gland would overheat.

4.  If the gaps are too small they could close due to the radial wear of the rings before the next scheduled overhaul preventing the rings from contacting the piston rod and sealing it

5.  I Don't Know

32. Which part of the crankshaft of a modern large two stroke diesel engine is most likely to be the origin point for crack initiation during service and therefore needs the greatest attention during maintenance inspection?

1. The oil holes.

2. The keyways.

3. The fillet radi.

4. The dowel pins and dowel holes

5. IDon't Know

33. HP pressure fuel pumps for medium speed engines are often provided with visible witness marks on the pump casing and the pump tappet. These along with flywheel position can be used to check the fuel timing for the individual pump. Wfrom the options given select what is actually indicated when the witness marks are aligned?

1. That the pump plunger has reached the end of its stroke.

2. That the pump plunger has just covered the spill port.

3. That the main piston for that particular cylinder is at top dead centre position.

4. That the pump plunger has just uncovered the spill port

5. I Don't Know

34. During inspection of the cylinder bore of a high speed diesel engine it is found that the surface of the liner has an extremely smooth and glassy appearance. From the options given select the best action, if any, that should be
    taken?

1. Use a flexible honing brush to deglaze the liner to a cross hatched plateau finish to improve both oil retention and running conditions

2. Clean the liner by rubbing with emery cloth using a circular motion to deglaze the liner to improve both oil retention and running conditions

3. With a steel brush, using a vertical motion, deglaze the liner to improve both oil retention and running conditions

4. No action is necessary as a smooth surface helps the piston rings achieve a good gas seal

5. IDon't Know

35. Some large slow speed diesel engines have jack bolt arrangements for retaining the main bearing top keep in place rather than the more conventional stud bolts. How does this arrangement affect the maintenance and checking
    procedures for the tie rods on the engine?

1. It has no effect since the tie rods and jacking bolts have completely separate functions.

2. The jacking bolts should be fully loaded before the tie rods are tensioned to avoid excess loads on the tie rods.

3. The tie rods and jacking bolts must be tightened simultaneously to avoid excess load on either component.

4. The tie rods should be fully tensioned before the jacking bolts are loaded to avoid overload of the bearing caps and frame structure

5. I Don't Know.

36. An accumulation test may be necessary for a steam boiler following repairs or modifications. Which of the given options does the accumulation test check?

1. The capacity of the safety valve to relieve pressure

2. The time taken for the boiler to reach operating pressure

3. The rate at which the boiler can generate steam.

4. The time taken to fill the boiler with water under steaming conditions.

5. I Don’t Know

37. A new gasket has been fitted to the manhole cover of a ballast tank. Which of the options given would be suitable to test that the new gasket is correctly fitted?

1. Fill the tank with water up to capacity

2. Fill the tank with water until it overflows through the air vent

3. Carry out a hose test on the manhole cover

4. Carry out an air pressure test on the ballast tank

5. I Don't Know

38. What action should be taken, in addition to isolating the leak, if the boiler water has become contaminated with a small amount of fuel oil due to a leaking heating coil?

1. Dose with coagulant and give the boiler a bottom blowdown.

2. Dose with coagulant and surface blow the boiler.

3. Dose with coagulant and continue to operate the boiler as normal.

4. Do nothing: a small amount of oil in the boiler is harmless.

5. IDon't Know

39. As part of a survey of a main steam boiler it is necessary to check the condition of the steam drum. What would be the preferred method for checking drum shell thickness in such a situation?

1. Use dye penetrant tester.

2. Use ultrasound equipment.

3. Use magnetic particle inspection equipment.

4. Drill a test hole in the shell to accurately measure the thickness.

5. I Don't Know.

40. A bilge strainer is blocking up during bilge pumping operations which is causing delays as the pump frequently loses suction and has to be primed. What action should be taken to remedy the situation?

1. Remove the strainer plate and drill larger holes in it and replace it in the housing to avoid blockages

2. Clean the strainer more frequently and clean out the bilge well at the first opportunity

3. Use a portable pump to avoid blockage of the strainer

4. Remove the strainer plate from the housing to avoid blockage and loss of suction

5. I Don't Know

41. A centrifugal pump gland has been repacked following overhaul of the pump. What is the correct method to ensure the pump shaft does not overheat when the pump is operating?

1. Tighten the gland to half way travel of the gland follower

2. Gradually tighten the gland follower with the pump running until the leakage is just a small steady flow

3. Tighten the gland follower as much as possible and then slacken it back again by one turn of the gland nuts

4. Gradually tighten the gland follower with the pump running until leakage at the gland stops

5. I Don't Know

42. A section of seawater pipe has been removed for maintenance. When refittingthe pipe after completing the work the bolt holes in the flanges are found to be misaligned. What procedure should be followed to finish the work?

1. Adjacent pipework should be slackened off to allow the pipe to be aligned. Any incorrectly positioned brackets should be adjusted after the pipe is refitted

2.  Use a chain block to pull the pipe flanges into alignment and leave it in place after the bolts are fitted to avoid overstressing the bolts.

3. Force the pipe into position and then hammer the bolts into the holes to hold the pipe flanges into alignment.

4. Use wooden wedges to force and hold the pipe into the correct position and then fit the bolts.

5. IDon't Know.

43. Which of the following tools can be safely sharpened using a pedestal grinder?

1. Hacksaw blade

2. Steel drill bit

3. Brass chisel

4.  Wooden wedge

5. I Don't Know

44. Chemical boiling out is one method that is used for cleaning the waterside of a steam boiler. Select from the givenoptions the likely circumstances under which this procedure would be considered necessary?

1. Excessive sludge build up in the water drum

2. .Oxygen pitting in the steam drum.

3. Contamination of the boiler water by oil

4. Excess chloride levels in the boiler water.

5. I Don't Know.

45. What is the main reason for using a ring spanner to tighten the brass nuts on the cover studs of a pump casing?

1. It will allow the nuts to be tightened correctly

2. it will minimise the risk of slipping off the nut or damaging the nuts

3. It can be adjusted to the exact size of the nut

4. The nuts can be tightened more with this type of spanner

5. I Dont Know.