Main engine unit survey and documents

.me survey .me unit survey .main engine survey

1. Planning

• Check the survey list of machinery
• Get exact date of survey and get immobilization and inform office
• Check previous record of maintenance
• Check and prepare all necessary spares and tools
• Check all lifting gear
• Check hydraulic pump, jacks, high pressure hose condition
• Ensure enough manpower and time available in port
• Read manual for special instruction and data.
• Carry out briefing for everyone involve, precaution, work to be done, and time available
• Carry out risk assessment

2. Tools

Prepare tools.                        

1. Piston and cylinder head
   • Hydraulic pump, hoses and hydraulic jacks
   • Piston lifting tool and cylinder head lifting tool
   • Piston inserting tool
   • Stuffing box spacer
   • Piston and cylinder head stand
   • Piston ring expander
   • Piston crown wear measuring template

2. Liner

• Liner lifting tool and liner support beam.
• Liner jack and jack support
• Liner calibration gauge
• Liner inspection ladder
• Stuffing box area covering plate

        3. Chain blocks

• Check its safe load carrying capacity
  • Check chain link condition
  • Check free movement of chain in both direction
  • Check safety lock for proper condition on hanging hook.
  • Check condition of hook for sign of crack or damage

 4. Eye bolts, shackles, wire sling and safety belt

• Check for safe load carrying capacity
  • Check overall condition for any damage
  • Check thread condition of eye and shackles

3. Safety during crane operation

• Don’t operate when ship is incline
  • Don’t press button simultaneously
• • Do not bypass limit switch
• • Do not operate if someone under or on the way
  • When 2 person directing, do not operate

4. After arriving port

• Once finished with engine, get immobilization permission
• Propeller clearance to be obtain form bridge
• Shut starting air system and hang notice not to start main engine
• Drain the air line, keep open
• Open indicating Cock
• Engage turning gear and turn ME with manual cylinder lubrication
• After half an hour stop LO pump
• Give time to cool engine
• Open crankcase door, lock on open position and give ventilation !
•  Isolate jcw inlet and outlet valve for particular unit and drain.
• Isolate fuel inlet and return valve for particular unit.
• Exhaust valve spring air to isolate
• After ventilation of crankcase check, atmosphere check for oxygen content, explosive gas and toxic gas
• Enclose space entry permit to complete
• No naked light inside crankcase
• Proper lighting to be ensure inside crankcase

5. Removal of connection

• with removal of following
• Remove exhaust bellow
• JCW outlet pipe before the valve
• Exhaust valve spring air connection
• Hydraulic actuator high pressure pipe
• Fuel injector high pressure pipe and connection
• Starting air valve connections

6. Removal of cylinder head

• Fit hydraulic jack on all cylinder head nuts and connect high pressure hose.
• Open jack vent and start to pump slowly
• Once air bubbles are removed, shut vent and stop pumping
• Ensure all jack vents are shut then pump to recommended pressure and stop pump
• Use tommy bar to loose nut
• Ensure all nuts are loose
• Release pressure, remove jacks and remove nuts
• Fit cylinder head lifting tool
• Lift slowly the cylinder head using ER crane
• Care to be taken when lifting, to make sure it does not come in contact with other cylinder head.
• Place the cylinder head on cylinder head stand

7. Removal of piston

• After proper ventilation of crankcase, remove the lashing of all secure bolts and remove require pipe connection
• Turn the piston to BDC and remove piston nut and lock device
• Fit the stuffing box spacer on piston rod palm
• Remove stuffing box securing bolts and its locking device
• Remove cylinder head metal gasket
• Clean liner surface of deposits at combustion area so as piston does not get stuck during extraction.
• Turn the piston towards TDC, carefully keeping eye on turning gear ampere
• Clean the lifting holes on crown
• Fit piston lifting tool, ensure all bolt secured
• Ensure crane is in mid-position and ship is even keel
• Slowly lift up piston ensure stuffing box spacer does not get in contact with diaphragm.
• Continue to lift, ensure piston is not swinging causing piston palm get in contact with liner
• Once out, lower the piston on its stand and put cover on stuffing box housing. !
•  Remove the lifting tool

8. Inspect and cleaning

Cylinder head

• Before cleaning,
  • check for carbon deposit.
  • Any trace of water leakage.
• After cleaning,
  • crack test to be carried out at change of section (around injector bore, exh valve bore area, indicating cock, starting air valve, relief valve)
• • Pressure test cylinder head cooling space
  • Keep ready for survey

Piston crown

• Check for burning at the top
• Use template to check wear
• Check for crack on top

Piston and piston ring

• before cleaning check for carbon deposit amount and condition
• check ring condition for sticky, broken, cracks
• after taking out, carry out thorough cleaning
• check for free movement
• check ring clearance and groove clearance

Piston skirt and side wall

• Check for any rubbing mark

Cooling passage

• Scaling due to poor water treatment
• Cracking due to high temperature
• Pressure test as per manual
• Take photo for before after for future reference
• Keep ready

Piston rod and stuffing box

• Piston rod diameter to check at different point in manual
• Record and compare previous record
• Carry out crack test at change of section of piston rod
• Check for any scratch mark
• Overhaul stuffing box, clean all parts, and check clearance of rings.
• Take photograph

Cylinder liner

• Check for dryness and oiliness, clover leafing, hard particle mark, polishing
• Check if scavenge port is choke & inspect
• Check for carbon deposit at top of combustion area
• Calibration to be check and recorded and compare with previous record !
• Check the lubrication points for cylinder lub oil flow by pumping manually !
• After cleaning, crack test to carry out around port edge.

9. Inspection of surveyor

• After cleaning and decarbonizing, all parts to be kept ready for survey. !
• Overhaul stuffing box with rings renewal as required box back !
• All joints, gasket and seal rings renewed and kept ready.
• All calibration and measurement record are recorded and kept ready for surveyor
• Overhauled exhaust valve and fuel injector ready for box up after completion of survey
• After survey, all parts box up as per manual and system to be put in running order, take all precautions. Check for leakage and rectify accordingly.

Piston material

.piston material

• Crown is made up of heat resistant forged steel alloy including chromium, nickel and molybdenum for heat and corrosion resistance without compromising on strength
• Skirt is made up of nodular cast iron or forged silicon aluminium alloy which has the advantage of being light, with low inertia, reducing bearing loading.