PACKAGE QUESTION LIST

UPT PUKP 03 - AKMI, Cirebon

Periode Paska Ulang 0412 AKMI (15 Dec 2017 - 16 Dec 2017)
ATT III -
Exam Code T-01-02 (Pasca) Level Function
1
Package Code A

Competency Operate main and auxiliary machinery and associated control systems
Package Code T3.1.04-C

1. A piston ring set for a trunk piston engine often includes a slotted ring tensioned by an internal spring. What is the purpose of
this type of piston ring?

a. It is an oil control ring.

b. It is the lowest compression ring.
c. It is a ring to seal the crankcase from the combustion chamber.
d. It is the firing ring.

2. A slow speed diesel engine is fitted with a slow turning facility. How would the slow turning normally be set to operate?

a. It should automatically operate before the normal start sequence following an engine stopped
period of more than 20 to 30 minutes when manoeuvring.
b. It should automatically operate before every normal start sequence.
c. It should automatically operate every 20 minutes when the engine is stopped during
manoeuvring.
d. It should be manually operated before the normal start sequence following an engine stopped
period of more than 10 minutes.

3. During the cycle of a four stroke diesel engine there is a load reversal on the bottom end bearing when the load transfers
from the upper part of the bearing to the lower part. What is the main cause of this load reversal on a modern, turbocharged,
medium speed diesel engine?

a. The lack of gas load to oppose the inertial forces generated during the exhaust stroke.
b. The suction effect on the piston during the air intake (induction) stroke.
c. The inertial forces generated during the upward strokes of the piston (compression and exhaust
strokes).
d. The light alloy materials used for the piston skirt.

4. During the normal operating cycle of a diesel engine there are side thrusts generated by the piston as it moves up and down
the cylinder due to the changing angle of the connecting rod. How are these side thrusts accommodated in a trunk piston
engine?

a. The side thrust is transmitted to the cylinder liner and the engine frame by the piston skirt in
way of the gudgeon pin.
b. The side thrust is transmitted to the cylinder liner and the engine frame by the piston rings.
c. The side thrust is transmitted to the cylinder liner and the engine frame by the piston crown.
d. The side thrust is transmitted to the engine frame by the crosshead bearing.

5. In a circuit diagram of a simple hydraulic circuit, which of the alternatives does the following symbol indicate?
 a. Double check valve.
b. Throttle valve.
c. Pressure relief valve.
d. Directional control valve.

6. It should be manually operated before the normal start sequence following an engine stopped period of more than 10
minutes.

In the event of a severe scavenge fire, which of the following is most likely to be seriously damaged?

a. Piston rod and stuffing box.

b. Exhaust valve.
c. Piston crown.
d. Crosshead bearing.

7. Large slow speed diesel engines are usually of the crosshead type and have various arrangements to deliver lubricating oil
directly to the crosshead bearings and guides to ensure adequate lubrication. Why are the crosshead bearings considered
differently to the other bearing in this type of engine in respect of lubrication requirements?

a. The running surfaces oscillate relative to each other during operation rather than rotate and
therefore full film hydrodynamic lubrication is not possible.
b. The lubricating oil has further to travel to the crosshead bearing and so a separate
arrangement is necessary
c. The crosshead bearing is more heavily loaded than other bearings in the engine so requires
more oil to keep it cool.
d. The crosshead bearing is closer to the engine cylinder and therefore runs hotter.

8. Many modern medium and high speed diesel engines operate at very high power ratings resulting in relatively high bearing
loads. In order to accommodate these loads the bearings are required to have a high load carrying capacity. What kind of
bearings are normally used for main and bottom end purposes to achieve this?

a. Thin steel shells lined with aluminium tin alloys.

b. Thick white metal types with the white metal cast into the keeps to give extra fatigue strength.
c. Thin steel shells with a thin white metal lining.
d. Thin steel shells with a copper lead lining and a running in overlay.

9. Some main propulsion medium speed engine installations operate with a hydraulic oil type fluid coupling between the engine
and the reduction gearbox instead of a mechanical clutch. With this type of installation a separate flexible coupling is not
normally fitted. Why is a separate flexible coupling usually omitted from this type of installation?

a. The hydraulic fluid in the coupling isolates the gearbox from the engine vibrations.
b. There is insufficient room to fit a flexible coupling between the engine and gearbox when a fluid
coupling is fitted.
c. There is natural slippage between the drive and driven parts of the fluid coupling and a flexible
coupling would prevent this slippage.
d. There are no engine torque variations in the drive when a fluid coupling is used so a flexible
coupling is not required.

10. The majority of medium speed main propulsion installations incorporate a reduction gearbox between the engine and the
propeller shaft. Why is this arrangement usually required?

a. So that the propeller operates in a relatively efficient speed range.

b. So that the engine can be more easily reversed.
c. So that the engine can be coupled to a controllable pitch propeller.
d. So that the engine can also drive a shaft alternator.

11. The peak pressure (maximum cylinder pressure) is often taken as an indicator of medium speed engine performance along
 with other parameters. What would be a typical peak pressure for a modern, highly rated, medium speed diesel engine?

a. 140 to 180 bar

b. 80 to 100 bar
c. 14 to 18 bar
d. 10 to 12 bar

12. The Total Base Number (TBN) is important as a measure of neutralizing ability of a diesel engine lubricating oil against strong
acids formed during combustion. What action should be taken if the results from an oil analysis show that the TBN of the
lubricating oil has reduced slightly?

a. Freshen up the system by draining of some of the oil and adding a quantity of fresh oil.
b. Purify the system oil in a centrifuge.
c. Take another lub oil sample and send it for analysis.
d. Pump the oil to a renovating tank and allow any contaminants to settle out and refill the system
with new oil.

13. What is the main purpose of bottom-blowing a boiler?

a. To remove any accumulated sludge from the water drum.

b. To control the water level of the boiler during normal operation.
c. To check the operation of the water gauge glasses.
d. To allow boiler water samples to be collected for testing.

14. What is the main purpose of an observation tank in a boiler feed system?

a. To check condensate returns for oil.

b. To allow dosage of boiler water treatment chemicals.
c. To allow the boiler water level to be monitored.
d. To provide a convenient point for boiler water test samples.

15. What is the most likely cause of black smoke at the boiler exhaust during normal operation of a steam boiler?

a. Insufficient combustion air.

b. Too much combustion air.
c. Water in the fuel.
d. Fuel oil temperature too high.

16. What is the most likely cause of the boiler exhaust gas being white in colour leaving the funnel?

a. Too much combustion air.

b. Insufficient combustion air.
c. A faulty or dirty burner tip
d. Low water level in the boiler.

17. What is the reason for fitting 'Rotocaps' to the cylinder head valves of some 4-stroke diesel engines?

a. To extend the service life of the valves by giving even heat and wear distribution.
b. To rotate the inlet valves during operation to improve air turbulence in the cylinder.
c. To help clear the cylinder of exhaust gas by spinning the exhaust valves during opening.
d. To prevent seizure of the cylinder head valves by keeping the valve spindles clean.

18. What is the term used to refer to the valve that prevents backflow of water from the boiler to the feed water system?

a. Feed-check valve
b. Feed-stop valve
c. Bottom-blow valve
d. Safety valve
19. When cleaning boiler burner nozzles that have just been in service the watch rating notices that the nozzle holes are partially
blocked. Which one is the preferred method to use in order to avoid damaging the nozzle holes?

a. Use cleaning wires starting with a small gauge and gradually work up to the full size of the
nozzle hole.
b. Use a standard drill bit in a hand drill to clear the blockage.
c. Poke the holes clear with a welding rod which has been ground down to size.
d. Knock the nozzle repeatedly on the work bench to try and dislodge the blockage.

20. When operating a propulsion installation consisting of medium speed diesel engines driving a controllable pitch propeller it is
possible to operate the combination of engine speed and propeller pitch in a number of different ways. What would be the
main reason for operating with constant speed and variable pitch?

a. To allow constant speed operation of a shaft generator while the engine load changes with
pitch variation.
b. To obtain maximum propeller efficiency over the load range of the engine.
c. To allow the engine to be operated with a load sensing governor instead of a speed sensing
governor.
d. To allow rapid load change and thrust reversal when manoeuvring.

21. When the boiler safety valves operate due to the boiler pressure being too high the excess steam is discharged to _______

a. the atmosphere via the atmospheric line

b. the main condenser
c. the auxiliary condenser
d. the engineroom bilges

22. Where would you normally expect to find the air vent cock on a steam boiler?

a. At the highest point of the steam drum.

b. At the superheater outlet
c. At the feed water inlet pipe connection.
d. On the highest point of the steam range.

23. Which of the following could cause a blowback from a steam boiler oil fired furnace?

a. Trying to ignite burner from hot brickwork

b. Having the fuel oil pressure too high
c. Having the fuel oil temperature too high
d. Opening air registers too quickly

24. Which of the given options best completes the following statement? You should never attempt to light a boiler until ______

a. the furnace purge sequence is completed.

b. the air register is fully open.
c. the feed water pump is running.
d. the gauge glass shows the water at normal working level.

25. Which of the given statements is true in relation to the features and operation of a 4 stroke diesel engine ?

a. The camshaft rotates with half the RPM of the crankshaft in a 4 stroke engine.
b. A 4 stroke engine has an ignition towards the end of every upward stroke of the piston.
c. A 4 stroke engine always has scavenge ports near the bottom of the cylinder liner.
d. 4 stroke engines are not required to have crankcase relief valves fitted.

26. Which symptoms would indicate piston blow-by when operating a 4 stroke trunk piston type engine ?
 a. Increased pressure in the crankcase and smoke at the crankcase vent.
b. Increased pressure in the air inlet manifold.
c. Increased temperature in the inlet air manifold on the engine.
d. Smoke and sparks from the scavenge manifold drains..

27. While on boiler watch in the engine room a rating is requested to assist with taking on stores. The task will take about half an
hour. What should the rating do?

a. Contact the engine officer on watch for permission to assist and to arrange a relief for the
duration of the store taking.
b. Raise the boiler water level above normal to make sure there is sufficient water while he is busy
with the stores.
c. Go and help with the stores but go back and check the boiler every 10 minutes.
d. Just ignore the request to assist with the stores.

28. While on boiler watch on an automatically controlled steam boiler the rating notices that the burner has failed to light
following a drop in steam pressure. What action should be taken?

a. Call the duty engineer immediately using the engineers call alarm.
b. Try and light the boiler burner manually.
c. Shut the steam stop valve to stop the steam pressure falling further.
d. Stop the feed water pump immediately in case the boiler overfills.

29. Why is it important that the combustion chamber of a boiler is properly ventilated prior to ignition?

a. To avoid an explosion in case any oil vapours are present from oil leakage into the furnace.
b. To ensure that there is sufficient air for proper combustion.
c. To cool the surfaces of the boiler furnace in case they give premature ignition of the burner.
d. To remove any deposits from the furnace wall.

30. Why should boiler sootblowers normally only be operated in the correct sequence?

a. To ensure soot is cleared progressively from the bottom tubes to the top and toward the boiler
uptakes.
b. To minimise loss of steam pressure.
c. So that the operator does not forget which sootblowers have been used.
d. To avoid excess stress in the boiler.