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.

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