CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER

Transcription

1 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF MARITIME AND COASTGUARD AGENCY SECOND ENGINEER (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 16 December hrs Examination paper inserts: Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate's examination workbook

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3 ENGINEERING KNOWLEDGE - MOTOR Attempt SIX questions only Marks for each part question are shown in brackets 1. (a) Sketch the lubrication systems for a crosshead engine, showing all essential valves and the fluid flow directions. (10) Describe how engine lubricating oil is maintained in a clean and effective condition. (6) 2. With reference to trunk piston, medium speed engines: (a) explain why multiple air inlet and exhaust valves are often fitted; (4) explain why exhaust valve rotation is employed; (4) explain how effective cylinder lubrication is obtained; (4) (d) describe how piston cooling is achieved. (4) 3. (a) Sketch a section through a main engine fuel injector, labelling the main parts. (6) State, with reasons, the factors which influence fuel atomisation. (5) State how atomisation of fuel deteriorates after prolonged injector operation. (5) 4. (a) Explain why high and low temperature cooling water systems are used for cooling main and generator diesel engines, stating which systems are cooled by the high and low temperature circuits. (6) Sketch the fresh water cooling systems for a main diesel engine, naming the main parts and describing how the temperature is controlled automatically. (10) 5. With reference to auxiliary boilers: (a) explain the process of scale formation; (6) list the different effects of using hard and soft water; (4) explain the danger of scale formation; (4) (d) explain the reason for taking two alkalinity tests. (2)

4 6. (a) State, with reasons, the safety procedures to be observed when overhauling a piston rod diaphragm gland. (6) Describe the procedure for overhauling a piston rod diaphragm gland, stating what checks must be made to ensure that the gland functions correctly when the engine is returned to service. (10) 7. With reference to charge air turbocharged systems: (a) state what instruments should be fitted in order to assess its performance; (4) explain how the information gathered from the instruments stated in part (a) is used to determine the performance in EACH of the following: (i) the turbocharger gas side; (4) (ii) the turbocharger air side; (4) (iii) the charge air cooling system. (4) 8. (a) Sketch a starting air system from the air compressors to engine starting devices labelling all main parts. (8) Explain how the compressed air system should be operated to ensure that there is sufficient pressure in the starting air receivers at all times to enable main and generator engines to be started. (4) List, with reasons, FOUR safety devices which are fitted in a compressed air system used for engine starting. (4) 9. With reference to main engine scavenge fires: (a) state, with reasons, the causes of a scavenge fire; (4) state the symptoms of a scavenge fire; (4) describe the actions taken to fight a scavenge fire, stating reasons for these actions. (8)

5 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF MARITIME AND COASTGUARD AGENCY SECOND ENGINEER (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 14 October hrs Examination paper inserts: Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate's examination workbook

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7 ENGINEERING KNOWLEDGE - MOTOR Attempt SIX questions only Marks for each part question are shown in brackets 1. With reference to engine charge air coolers: (a) state why charge air coolers are fitted to turbocharged diesel engines; (2) (d) describe how the performance of a charge air cooler may be assessed during engine operation; (4) explain how it may be determined that condensate from the charge air cooler is being effectively drained during engine operation; (4) describe the possible consequences of large amounts of water entering an engine charge air inlet system, explaining why there may be greater risk of water ingress on a 4-stroke engine than on a 2-stroke engine. (6) 2. (a) Describe, with the aid of a sketch, a diesel engine fuel injection system for which the start and end of fuel injection may be changed during engine operation, explaining how fuel injection pressure is achieved and how injection timing is controlled. (10) Explain why change in fuel injection timing may need to be varied during engine operation, stating the possible consequences of running an engine for prolonged periods either with early inection or with late injection. (6) 3. With reference to direct drive, reversible engines: (a) explain how the risk of fires and explosions may be minimised in the cylinder start air lines; (8) explain the procedure to be followed while manoeuvring: (i) if a hot start air pipe is discovered; (4) (ii) if a safety device has ruptured due to a start air line explosion. (4) 4. With reference to scavenge fires: (a) explain the causes of a scavenge fire, stating how such an outbreak is brought to the notice of the duty engineer; (4) describe the action which should be taken in order to extinguish a scavenge fire; (6) state, with reasons, the checks which must be made after a scavenge fire has been extinguished in order to assess possible engine damage and minimise the risk of future scavenge fires. (6)

8 5. With reference to the replacement of a main engine fuel injection pump whilst the vessel is at sea: (a) state, with reasons, THREE risks involved in the operation, explaining how they may be overcome; (6) describe, with the aid of a sketch or sketches, the procedure involved in the replacement of the fuel pump, explaining the checks which must be made to ensure that the pump operates correctly in service. (10) 6. (a) Describe the lubricating oil flow within a two-stroke crosshead engine. (8) Describe the difference in properties between the lubricating oils used in crosshead and trunk type engines. (8) 7. (a) Describe, with the aid of a sketch or sketches, the procedure for preparing a main bearing for inspection. (6) Describe THREE defects which may be found on the journal and bearing shell, stating their possible causes. (6) Describe a procedure for checking main bearing clearance. (4) 8. (a) Explain why boiler water treatment is necessary even though distilled water is used as feed water. (4) Describe the procedure for obtaining a representative boiler water sample. (6) List the tests normally carried out on boiler water, stating what information the results of the tests provide about the condition of the boiler water. (6) 9. (a) State what clearances are required between the piston rings and the piston and cylinder liner indicating why such clearances are required. (6) Describe how each of the piston ring clearances stated in part (a) are measured. (5) Explain why piston ring clearances must be kept within set limits. (5)

9 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF MARITIME AND COASTGUARD AGENCY SECOND ENGINEER (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 22 July hrs Examination paper inserts: Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate's examination workbook

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11 ENGINEERING KNOWLEDGE - MOTOR Attempt SIX questions only Marks for each part question are shown in brackets 1. (a) Describe the procedure to take main engine crankshaft deflections. (10) List the occasions when they should be taken. (2) List the occasions with reasons when they should NOT be taken. (4) 2. (a) Sketch, in section, an engine charge air system from the turbocharger to the engine scavenge ports, indicating all fluid flows, showing main instrumentation and naming the main parts. (10) Explain why it is necessary to cool the charge air after a turbocharger. (4) Explain why it is necessary to remove water from the charge air. (2) 3. (a) Sketch a starting air system which may be used for starting a generator engine, explaining how the system operates. (8) Explain how a generator engine is set up so that it may be started automatically by the Power Management System, stating the precautions which must be observed at an engine selected for automatic standby. (8) 4. With reference to cylinder liner calibration: (a) describe the method of calibrating a cylinder liner, stating the purpose of the procedure. (10) explain how the accuracy of the readings is ensured; (3) state the types of liner damage. (3) 5. (a) Determine the specific fuel consumption for a main engine with an output power of 10000kW and a daily fuel consumption of 36 tonnes. (4) Sketch in phase and out of phase indicator diagrams, explaining how these are used to help maintain correct specific fuel oil consumption. (8) State TWO engine faults which may cause an increase in the specific fuel oil consumption, explaining their effect on the draw card sketched in part. (4)

12 6. (a) State the advantages of using a common rail fuel injection system; (6) Describe, with the aid of a sketch, a common rail fuel injection system. (10) 7. (a) Describe, with the aid of a sketch, an engine fuel injection system which may be controlled electronically. (6) Explain how the fuel injection system described in part (a) operates. (5) Explain how the fuel injection timing of the system described in part (a) may be varied by the operator, stating why it might be necessary to change the fuel injection timing. (5) 8. (a) Explain what is meant by the term accumulation of pressure, stating its limit; (2) Sketch the lower end of a high-lift safety valve; (8) Describe the operation of the valve sketched in part b. (6) 9. With reference to crankcase explosions: (a) describe, with the aid of a sketch, the crankcase explosion relief door for a diesel engine; (9) explain how a crankcase explosion relief door functions in the event of an explosion; (4) state a reason for the crankcase explosion relief doors opening, other than because of an explosion. (3)

13 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF MARITIME AND COASTGUARD AGENCY SECOND ENGINEER (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 08 April hrs Examination paper inserts: Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate's examination workbook

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15 ENGINEERING KNOWLEDGE - MOTOR Attempt SIX questions only Marks for each part question are shown in brackets 1. (a) Describe, with the aid of a sketch, a fuel booster module which can supply HFO and MGO to the ship's main and auxiliary diesel engines. (8) Explain how the fuel booster module described in part (a) operates to change the entire engine installation fuel supply from HFO to MGO. (4) Explain how one auxiliary engine supplied by the booster module described in part (a) may be flushed through with MGO whilst other engines remain operating on HFO. (4) 2. (a) State, with reasons, the items which must be considered when undertaking a risk assessment prior to replacing a crosshead engine hydraulically actuated exhaust valve. (6) Describe the procedure for replacing a crosshead engine hydraulically activated exhaust valve, explaining what checks must be made before the engine is restarted. (10) 3. (a) Describe how a watchkeeper may become aware of poor combustion in one or more, but not all, main engine cylinders. (4) Describe the checks which should be made in order that the cause of poor combustion in one or more, but not all, main engine cylinders may be determined. (6) Describe how the cause of poor cylinder combustion, identified in part may be corrected. (6) 4. (a) Describe a procedure for checking the clearance of a diesel engine bottom end bearing. (6) Explain the possible consequences of operating an engine with excessive bottom end bearing clearances. (4) Describe a procedure for restoring an excessive bottom end clearance to its correct value. (6) 5. (a) Describe, with the aid of a sketch, a complete trunk piston diesel engine lubricating oil system indicating the flow of oil to all parts of the engine. (8) State, with reasons, FOUR properties required of a trunk piston engine crankcase oil. (4) Explain how trunk piston engine crankcase oil is maintained in a suitable condition for prolonged use in the engine. (4)

16 6. (a) Write instructions for operating the main propulsion and electrical generating machinery in the event of failure of the Integrated Alarm, Monitoring and Control System. (10) Explain how engine performance and cylinder power balance may be determined if the Integrated Alarm, Monitoring and Control System has failed. (6) 7. (a) Explain why a crankcase explosion occurs. (4) Explain the possible consequences of a crankcase explosion. (4) Explain why a scavenge fire occurs. (4) (d) Explain the possible consequences of a scavenge fire. (4) 8. (a) Describe the actions to be taken to enable a main engine to be operated in the event of one of two constant pressure turbochargers suffering complete bearing failure and damage to the journals which cannot be rectified. (8) Describe the actions to be taken to enable a main engine to be operated in the event of damage to a charge air cooler preventing the circulation of water through the cooler. (8) 9. (a) Sketch a starting air system from the air compressors to engine starting devices labelling all main parts. (8) Explain how the compressed air system should be operated to ensure that there is sufficient pressure in the starting air receivers at all times to enable main and generator engines to be started. (4) List, with reasons, FOUR safety devices which are fitted in a compressed air system used for engine starting. (4)

17 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF MARITIME AND COASTGUARD AGENCY SECOND ENGINEER (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 10 December hrs Examination paper inserts: Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate's examination workbook

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19 ENGINEERING KNOWLEDGE - MOTOR Attempt SIX questions only Marks for each part question are shown in brackets 1. With reference to main engine scavenge fires: (a) state, with reasons, the causes of a scavenge fire; (4) state the symptoms of a scavenge fire; (4) describe the actions taken to fight a scavenge fire, stating reasons for the actions. (8) 2. (a) Describe, with the aid of a sketch, an engine fuel injection system which may be controlled electronically. (6) Explain how the fuel injection system described in part (a) operates. (5) Explain how the fuel injection timing of the system described in part (a) may be varied by the operator, stating why it might be necessary to change the fuel injection timing. (5) 3. (a) State what clearances are required between the piston rings and the piston and cylinder liner indicating why such clearances are required. (6) Describe how each of the piston ring clearances stated in part (a) are measured. (5) Explain why piston ring clearances must be kept within set limits. (5) 4. With reference to direct drive, reversible engines: (a) explain how the risk of fires and explosions may be minimised in the cylinder start air lines; (8) explain the procedure to be followed while manoeuvring: (i) if a hot start air pipe is discovered; (4) (ii) if a safety device has ruptured due to a start air line explosion. (4) 5. With reference to auxiliary boilers: (a) explain the process of scale formation; (6) list the different effects of using hard and soft water; (4) explain the danger of scale formation; (4) (d) explain the reason for taking two alkalinity tests. (2)

20 6. (a) Sketch a power card stating why it is taken. (4) Explain how power balancing across all cylinders of an engine is achieved. (8) Explain what is meant by the term draw card, stating what information can be taken from it. (4) 7. With reference to main engine crankshaft deflection: (a) describe the procedure to measure deflections; (10) list the occasions when should they be measured; (4) list the occasions when they should not be measured. (2) 8. (a) Sketch the lubricating system for a main diesel engine, labelling the MAIN components. The sketch should indicate the direction of oil flow in the pipes. (8) State the purpose of the components sketched in part (a). (4) State, with reasons, the properties of the lubricant required for lubrication of the main engine components served by the system sketched in part (a). (4) 9. (a) Explain what is meant by supercharging. (2) Explain the differences between the two basic types of turbocharging. (6) Explain, with the aid of a sketch, the operation of sequential turbocharging. (8)

21 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF MARITIME AND COASTGUARD AGENCY SECOND ENGINEER (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 15 October hrs Examination paper inserts: Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate's examination workbook

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23 ENGINEERING KNOWLEDGE - MOTOR Attempt SIX questions only Marks for each part question are shown in brackets 1. With reference to charge air turbocharged systems: (a) state what instruments should be fitted in order to assess its performance; (4) explain how the information gathered from the instruments stated in part (a) is used to determine the performance in EACH of the following: (i) the turbocharger gas side; (4) (ii) the turbocharger air side; (4) (iii) the charge air cooling system. (4) 2. (a) State the effect on the cylinder combustion and describe the possible consequences for engine components in EACH of the following conditions: (i) early fuel injection; (5) (ii) late fuel injection. (5) State ONE means of changing fuel injection timing during engine operation, describing how the change in timing is brought about. (6) 3. (a) Explain why tie rods are fitted to crosshead engines. (6) Describe a procedure for checking tie rod tension, indicating when the checking of tie rod tension should be carried out other than at routine times. (6) Explain the possible consequences of uneven tie rod stresses. (4) 4. With reference to diesel engine driven emergency generators: (a) describe the requirements for EACH of the following: (i) starting systems; (3) (ii) cooling systems; (3) (iii) fuel systems. (3) Describe the procedure for manual test running of an emergency generator off load. (7)

24 5. (a) State which instruments are fitted at a local engine side control stand, in EACH case explaining why the device is required at that location. (4) (d) Describe how a main engine is changed over from remote control to local engine side control which allows manual operation of the fuel linkage. (4) Describe the procedure for manoeuvring a main engine from the local engine side position when the governor is inoperative. (4) Describe the precautions which must be observed when manoeuvring the main engine from the local engine side position. (4) 6. (a) Explain why high and low temperature cooling water systems are used for cooling main and generator diesel engines, stating which systems are cooled by the high and low temperature circuits. (6) Sketch the fresh water cooling systems for a main diesel engine, naming the main parts and describing how the temperature is controlled automatically. (10) 7. (a) State, with reasons, the safety procedures to be observed when overhauling a piston rod diaphragm gland. (6) Describe the procedure for overhauling a piston rod diaphragm gland, stating what checks must be made to ensure that the gland functions correctly when the engine is returned to service. (10) 8. (a) Explain why four-stroke engine exhaust valves generally require more frequent attention than air inlet valves. (4) Explain exhaust valve design features which assist in prolonging the period between valve overhauls. (6) Explain how the use of multiple air inlet and exhaust valves improves cylinder performance. (6) 9. With reference to exhaust gas economisers/waste heat boilers: (a) explain the possible consequences of not maintaining the gas side heat transfer surfaces in a clean condition; (5) describe how the gas side heat transfer surfaces are maintained in a clean condition during operation of the unit; (6) describe a gas side out-of-service cleaning method, explaining why out-of-service cleaning is necessary even though in-service cleaning is carried out. (5)

25 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF MARITIME AND COASTGUARD AGENCY SECOND ENGINEER (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 16 July hrs Examination paper inserts: Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate's examination workbook

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27 ENGINEERING KNOWLEDGE - MOTOR Attempt SIX questions only Marks for each part question are shown in brackets 1. (a) Describe, with the aid of a sketch, the procedure for checking the guide clearances on a crosshead main engine. (10) Explain how the guide clearances are adjusted. (6) 2. With reference to Vee-type medium speed engines: (a) sketch an arrangement for attaching two connecting rods to the same crank pin; (5) describe, with the aid of a sketch, how a cylinder cover is removed from the engine; (6) describe how a piston is removed from the engine. (5) 3. (a) Sketch a section through a main engine fuel injector, labelling the main parts. (6) State, with reasons, the factors which influence fuel atomisation in a fuel injector. (5) State how atomisation of fuel deteriorates after prolonged injector operation. (5) 4. (a) Explain the possible consequences of running an engine with cylinder powers excessively out-of-balance. (4) Explain why perfect power balance between cylinders is not possible. (4) (d) Describe how cylinder power and performance can be assessed for a medium speed engine. (4) Describe the adjustments which must be made to restore reasonable cylinder power balance to a medium speed engine. (4) 5. (a) State the possible causes of turbocharger bearing failure and how this may be minimised. (8) Describe, with the aid of a sketch, the procedure for removing turbocharger bearings for inspection. (6) State the clearances to be checked when overhauling a turbocharger bearing system, explaining why these clearances are required. (2)

28 6. (a) Explain why main engine starting air compressors are of the multi-stage type. (4) Explain why intercooling of air is employed between compressor stages. (4) Explain why automatic drain traps are fitted to air compressor coolers. (4) (d) Explain why it is necessary to remove oil and water from the air leaving the starting air compressor. (4) 7. (a) Describe, with the aid of a sketch, a boiler burner fuel system, explaining how the main flame is ignited. (8) Explain how the air and fuel supply to the burner are regulated together in the system described in part (a). (4) Explain how the boiler burner system described in part (a) may be regulated manually, in the event of the remote control system failing. (4) 8. (a) Describe, with the aid of a sketch, the procedure for changing a crosshead main engine exhaust valve. (8) Describe the connections and checks which must be made after a crosshead main engine exhaust valve has been changed in order to ensure that it will operate correctly. (8) 9. With reference to main engine starting air systems: (a) state the regulatory requirements for air receivers; (2) describe TWO possible causes of an air start line explosion; (6) describe safety devices fitted to reduce an explosion occuring; (6) (d) describe watchkeeping procedures to minimise the risk of an explosion. (2)

29 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY - MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF MARITIME AND COASTGUARD AGENCY SECOND ENGINEER (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 26 March hrs Examination paper inserts: Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate's examination workbook

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31 ENGINEERING KNOWLEDGE - MOTOR Attempt SIX questions only Marks for each part question are shown in brackets Section A 1. (a) State, with reasons, risks which may be encountered during the replacement of a main fuel pump. (6) Describe, with the aid of a sketch, the replacment of a main engine fuel pump. (10) 2. (a) Describe, with the aid of a sketch, the lubricating oil systems for a crosshead main engine, stating the purpose of the main components. The sketch must indicate the direction of oil flow in the pipes and main items must be labelled. (10) State, with reasons, THREE properties of ONE of the lubricants required for the systems described in part (a). (6) 3. (a) Explain the steps to be taken to ensure that a vessel, which normally operates on HFO, is operating completely on low sulphur fuel prior to entering an environmentally sensitive area where sulphur emission controls apply. (10) Explain the possible consequences of operating an engine on fuel with a very low sulphur content (below 1% sulphur) after running on normal HFO. (6) 4. (a) State the problems associated with four-stroke engine exhaust valves which are not associated with the air inlet valves. (2) Describe the features of exhaust valve system design which are intended to overcome the problems stated in part (a). (6) Explain how the use of multiple cylinder head valves improves engine operating efficiency. (8) 5. (a) Describe, with the aid of a sketch, the procedure for removing a piston from a cylinder of a medium speed, Vee-type engine; it may be assumed that the cylinder cover has already been removed. (8) Describe how the piston rings are removed from a medium speed engine piston, stating how the piston ring grooves are checked and new piston rings are fitted. (8)

32 6. (a) Sketch a section through a turbocharger showing the bearings in place and indicating how bearing lubrication is achieved. (8) Describe a procedure for the replacement of bearings for the turbocharger sketched in part (a), stating the checks which must be carried out before the turbocharger is returned to service. (8) 7. (a) Sketch a main engine cooling water system, showing the coolant flow in all parts of the system. (8) Explain how the correct temperature is maintained in all parts of the system, for the main engine cooling system sketched in part (a). (4) Explain how the correct cooling temperatures may be maintained in the system sketched in part (a), in the event of the remote monitoring and control system failing. (4) 8. With reference to a main engine starting air system, explain EACH of the following: (a) why automatic drain traps are fitted at air compressor coolers; (4) (d) why it is necessary to remove oil and water from the air leaving the starting air compressor; (4) what facilities are required to enable starting air compressors to be started and stopped automatically; (4) why drains are required on starting air receivers and in other parts of the starting air system even though drains are fitted at starting air compressors. (4) 9. With reference to waste heat recovery systems: (a) explain why a steam dump facility may be required; (4) describe how a steam dump operates during running of the main engine system; (4) write instructions for in-service cleaning of the gas side of a waste heat steam generation system. (8)

33 CERTIFICATES OF COMPETENCY IN THE MERCHANT NAVY MARINE ENGINEER OFFICER EXAMINATIONS ADMINISTERED BY THE SCOTTISH QUALIFICATIONS AUTHORITY ON BEHALF OF THE MARITIME AND COASTGUARD AGENCY STCW 95 SECOND ENGINEER REG. III/2 (UNLIMITED) ENGINEERING KNOWLEDGE - MOTOR TUESDAY, 29 MARCH hrs Examination paper inserts: Worksheet Q4 Notes for the guidance of candidates: Materials to be supplied by examination centres: Candidate s examination workbook

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35 ENGINEERING KNOWLEDGE MOTOR Attempt SIX questions only All questions carry equal marks Marks for each part question are shown in brackets 1. (a) Describe, with the aid of sketches, the procedure for checking the guide clearances on a crosshead main engine. Explain how the guide clearances are adjusted. (10) (6) 2. With reference to V-type medium speed engines: (a) sketch an arrangement for attaching two connecting rods to the same crank pin; describe, with the aid of sketches, how a cylinder cover is removed from the engine; describe how a piston is removed from the engine. (5) (6) (5) 3. (a) Sketch a section through a main engine fuel injector, labelling the main parts. State, with reasons, the factors which influence fuel atomisation in a fuel injector. State how atomisation of fuel deteriorates after prolonged injector operation. (6) (5) (5) 4. (a) On Worksheet Q4 complete a risk assessment for removing a crosshead diesel engine cylinder cover. Describe, with the aid of sketches, the procedure for removing a crosshead engine cylinder cover and landing it on the engine room plates. (8) (8) [OVER

36 5. (a) Explain why approximate power balance between cylinders is necessary. State why exact power balance between cylinders is not possible with an operating engine. Describe how cylinder power and performance can be assessed for a medium speed engine. (d) Describe how individual cylinder power can be adjusted. (4) (4) (4) (4) 6. (a) State what clearances are required between the piston rings and the piston and cylinder liner indicating why such clearances are required. Describe how each of the piston ring clearances stated in Q6(a) are measured. Explain why the values of piston ring clearances are limited. (6) (5) (5) 7. (a) Describe, with the aid of sketches, the procedure for removing turbocharger bearings for inspection. State the clearances to be checked when overhauling a turbocharger bearing system, explaining why these clearances are required. (10) (6) 8. (a) Explain why main engine starting air compressors are of the multi-stage type. Explain why intercooling of air is employed between stages. Explain why automatic drain traps are fitted at air compressor coolers. (d) Explain why it is necessary to remove oil and water from the air leaving the starting air compressor. (4) (4) (4) (4) 9. (a) Describe, with the aid of a sketch, a boiler burner fuel system, explaining how the main flame is ignited. Explain how the combination air and fuel supply to the burner are regulated together in the system described in Q9(a). Explain how the boiler burner system described in Q9(a) may be regulated manually, in the event of the remote control system failing. (8) (4) (4)