National Apprentice & Industrial
Training Authority
Report on Industrial Training
At
Colombo dockyard PLC
Colombo 13
Institute of Technology University of Moratuwa
Name
: G V Dilshan
Student Number
: 18/IT/MR/653
Course
: National Diploma in Technology
Field
: Marine Engineering Technology
Training Period
: 24th June 2022-23rd December 2022
Contents
Engine fitting shop ................................................................................................................................................... 1
Introduction ......................................................................................................................................................... 1
Four Stroke engine fuel pump was assembled. .................................................................................................. 1
Four Stroke engine cylinder cover was assembled. ............................................................................................ 2
Four stroke cylinder cover was pressure tested ................................................................................................. 3
Hull construction ..................................................................................................................................................... 4
Introduction ......................................................................................................................................................... 4
PAG Machine (Portable Automatic Gas cutting) ................................................................................................. 4
Line heating procedure ....................................................................................................................................... 5
Ship repair division .................................................................................................................................................. 6
Introduction ......................................................................................................................................................... 6
Propeller blades were removed. ......................................................................................................................... 6
Cross head engine main bearing was overhauled ............................................................................................... 7
Cross head engine big end bearing was removed. .............................................................................................. 8
Cross head engine Crosshead bearing was removed .......................................................................................... 9
Hull treatment ....................................................................................................................................................... 10
Introduction ....................................................................................................................................................... 10
Blasting and painting of ship repair activity ...................................................................................................... 10
Blasting and painting procedure for new construction..................................................................................... 12
Engine fitting shop
Introduction
Engine fitting shop done maintenance and overhauling of marine engines, auxiliary engine and
their sub components some of them are propellers, propeller shaft, valves, heat exchanger,
turbocharger and pump after that overhauling the components of ship. Therefore, this is a main depart
section of the Colombo Dock yard.
Engine fitting shop has been divided to several divisions.
1.
2.
3.
4.
5.
6.
7.
8.
Valves
Turbo chargers
Pumps
Engines
Heat exchanges
Propellers
Propeller shaft seals
Washing and cleaning area
Four Stroke engine fuel pump was assembled.
1) Fuel pump was mounted on bench wise.
2) 3-O-ring were inserted from top of the pump housing
3) Barrel was inserted to the pump & tightened by four Alan screws.
4) Delivery valve and spring was inserted to the barrel.
5) Fuel delivery block and spacer ring was assembled using four Alan screws.
6) Insert two spill port nuts to the housing
7) Fuel pump was mounted to bench wise upside down.
8) Fuel rack and pinion was inserted to the housing.
9) Fuel rack guide nut and the cir clip was inserted.
10) Top spring cover, spring with plunger, bottom spring cap, bottom spring cover was respectively
inserted to the barrel.
11) Push the spring using drill machine and insert cir clip.
12) Inspect if there any unusual play by moving fuel rack.
13) Fuel delivery line connecting block was assembled using two Alan bolts with gasket and Orings.
Four Stroke engine cylinder cover was assembled.
1)
2)
3)
4)
5)
6)
7)
Cylinder cover was cleaned using kerosene oil & power brush.
Valve seat surface were inspected for wear, debris and shroud marks.
If there any damage valve seat removes them.
New valve seats were installed using liquid nitrogen.
When removing the valve seat always be careful not to damage valve guides.
If any valve guide damage new valve guides were installed.
After installing new valve seats and guides insert valve to the cylinder cover and check if there
any abnormal play in exhaust valve.
8) If there was any play inspect the valve guide.
9) Valve seats and valves were blue tested.
10) Two o- rings were inserted to the cylinder cover and coated with grease.
11) Cooling water jacket was assembled to the cover.
12) If there any valve seat does not fulfill blue test lap them.
13) Cylinder cover seating surface was lapped.
14) Valve springs and rotor caps were installed.
15) Valve quarters were installed using special fools.
16) Indicator cock and starting air valve assembled to the cylinder cover.
Four stroke cylinder cover was pressure tested
1)
2)
3)
4)
5)
6)
Insert the o- rings and grease them
Cooling jacket was assembled to the cylinder cover using alan bolts.
Jacket water outlet holes on the cooling jacket was covered using copper brush.
Connect the manual water pressure pump to the jacket water inlet of the cylinder cover.
Increase pressure up to 0.5Mpa.
Check if there any leakages specially through valve seats.
Hull construction
Introduction
Mainly doing in the shop is hull construction. Hull means all the surfaces without deck and
bottom at the ship. Normally ship bottom has two plate system.
These are some process done by hull construction work shop.
1.)
2.)
3.)
4.)
Metal marking
Plate cutting
Lofting
Plate rolling
5.) Plate bending
6.) Line heating
7.) Welding
8.) New construction
These shops use bellow machineries.
1)
2)
3)
4)
5)
Pressed machines
Plasma cutting (CNC)
Flame cutting (CNC)
Rolling machines
Gas cutting (Heating bed)
PAG Machine (Portable Automatic Gas cutting)
1)
2)
3)
4)
5)
6)
7)
Ensure all the related safety precautions are taken.
Place the work piece on the heating bed and clean it.
Place the metal track some constant distance from the cutting line.
Place the cutting nozzle relevant to the plate thickness adjust the nozzle angle.
Then put it on the iron trail and adjust the height between the plate and nozzle.
Ensure it moves constant speed on paths.
Connect the PAG cutting machine with correct gas line
Red-acetylene
Blue-oxygen
8) Carefully turn on the flame by using lighter.
9) Run pug machine through the cutting line while examine the cutting.
Line heating procedure
1.)Bring the plate on to the heating bed.
2.)Mark the lines on template on the metal sheet.
3.)Mark the rolling lines both ends of the plate from template .
4.)Mark the heating lines as necessary to the parallel to the rolling lines.(flame lines)
5.)Put the plate on wooden wedges to observe the rolling.
6.)Start the heating through frame lines.(650°c) while cooling by water jet as necessary .
7.)Check the formed shape using templates time to time.
8.)Then put the templates on the frame lines perpendicular to the plate using and check the sight line
marks are linear.
Ship repair division
Introduction
Ship repair division is the most vital workshop in the Colom k dockyard plc. Most of the ships have
two Stoke slow speed engines. These engines require proper maintenance for efficiency operation.
That task completed by ship repair division.
Following task are mainly carried out by the ship repair division.
1)main and auxiliary engine overhauling
2)Crosshead bearing main bearing repair
3)rudder and propeller repair and mounting
4)turbocharger overhauling
Propeller blades were removed.
1.) propeller blades were secured using chain blocks and belts which is mounted on ship Hull.
2.) The blade which was going to remove was taken to the top position of the propeller by using
chain block.
3.) Six nuts removed from propeller head using special wrench and hammer.
4.) propeller blades were carefully lowered and placed on wooden blocks.
5.) circular hole on the propeller hub was covered using polythene.
Cross head engine main bearing was overhauled
1.) crank case doors were opened and cleaned inside the crankcase.
2.) main bearing lubricating pipe was dismantled
3.) oil release nut on the jack bolt was released.
4.) hydraulic oil pressure was added to the jack using hydraulic pump until oil drain from the oil
release nut hole.
5.) oil release nut was replaced.
6.) 620bar hydraulic oil. Pressure was added to the jack and using hydraulic jacking pump and
nut was loosened.
7.) jacking nut was removed.
8.) Main bearing cap was taken out using chain blocks.
9.) metal beam was inserted to the crankcase.
10.)
Two hydraulic Jacks were placed on metal beam.
11.)
crankshaft was lifted using hydraulic Jacks until clearance make up between lower
bearing shell and crank shaft.
12.)
steel cable was passed around the lower bearing shell.
13.)
lower bearing shell was pulled out using chain blocks.
Cross head engine big end bearing was removed.
1.) crankcase doors were opened and cleaned inside.
2.) Engine was turned to TDC.
3.) Bottom half of the big end was supported using eye bolts shackles and chain blocks.
4.) Bottom half holding nuts were loosened using hydraulic jack.
5.) nuts were removed.
6.) Bottom half of the bearing was lowered in crankcase using chain blocks.
7.) Crosshead was locked at TDC using tools mounted on guide shoose.
8.) connecting rod and crankshaft was turned respectively using chain blocks and turning gear at
the same time until top half of the big end bearing is separated from the crank pin.
9.) crank pin and big end bearing top half was cleaned.
10)
Big end bearing top shell was taken out.
Cross head engine Crosshead bearing was removed
1) crankcase doors were opened and inside was cleaned.
2) crank was turned to BDC.
3) Hydraulic jack locking nuts were loosened.
4) hydraulic jack nuts were loosened using hydraulic jacking pump by adding 600bar pressure.
5) lift the cross head bearing uper shell using chain blocks.
6) inspect the upper shell.
7) crank was turned to TDC.
8) cross head was locked on guide shoes using retaining pins.
9) connecting rod was secured using holding ropes and chain blocks.
10) crank was turned down carefully while guiding the connecting rod with holding ropes, until
Crosshead bearing bottom shell accessible.
11)bearing shell was dismantled by using Alan screws.
Hull treatment
Introduction
Hull treatment shop is carried out the jobs of blasting and painting in dockyard. This work shop carried
out new construction old ship paintings process with the help of foreign paint companies.
This shop decided when the time to coating process according to the environment condition and thus
shop has fully whether controlled blasting chamber.
These are some processes done by Hull treatment shop
1)high pressure water jetting
2)grit blasting
3)surfaces preparation inspection tests
4)coating inspection tests
5)painting
Blasting and painting of ship repair activity
1)barnacles were removed by scrapers
2)ship Hull was washed using high pressure water until all the muds alga matrons salt and other
contaminations removed.
3)After pressure washing if there were any oil or grease on ship hull cleaned them by applying
detergent(ONGR) and pressure water(250bars)
4)then Hull was inspected by coating advisor, ship surveyor and dockyard from top side, vertical
bottom and flat bottom.
5)Blasting agreement was prepared y them according to the surface condition (paint peel off, putting
corrosion, previous corrosion)
6)Blasting process was carry out according to the blasting agreement using corresponding blasting
standards.
7)After the blasting process completed surface preparation test was carried out according to the
owner’s requirements.
8)if test results OK coating process stats according to the paint specifications sheet.
Important consideration on coating process
•
•
Surface condition
o Salt test
o Dust test
o Profile test
Micro climate conditions
o Air temperature
o Relative humidity
o Dew point
o Surface temperature
•
•
Applications method
Operator skill
Blasting and painting procedure for new construction
1.
2.
3.
4.
5.
6.
Unit was washed by compressed water.
Unit was inserted to the blasting chamber.
Welding seems and edges were grit blasted.
The unit surface was grit blasted to SA 2.5
Unit surface was cleaned by air vacuumed.
Surface preparation inspection test welding splatters pin holes blow holes tests were carried out
in unit
7. If test results ok coating process starts according to the paint specification sheet.
8. After 1st coat fist S/C coat applied.
9. Then 1st application inspection test carried out.
10. The next coat applied.(inspection tests carried out applying after each coat)