Author Archives: Mohammud Hanif Dewan

COC ORAL EXAM PREPARATION (PART- 5) – BOILER

Exhaust Gas Boilers:

  • About 30% – 34% of Fuel Energy input to engine are discharged to Exhaust Gas, as Thermal Energy.
  • This thermal energy is converted into useful work in Exhaust Gas Boiler.

Cochran Exhaust Gas Boiler:
1. A double-pass, vertical type, in which Exhaust gases from ME pass through 2 banks of tube.
2. Served as an efficient silencer, when the boiler is in use.
3. A separate Silencer, always fitted along with exhaust gas boiler, to be used when the boiler is generating more steam than required.
4. All or part of exhaust gases can be directed to the Silencer and atmosphere, without going through the boiler.
5. Working Pressure is around 7 bars.

Composite Boiler (Composite type Cochran boiler):

1. If Exhaust Gases and Oil fire can be used at the same time, it is termed Composite Boiler.
2. In double-pass, composite type Cochran Boiler, it provides a separate tube nest for exhaust gas passage, situated immediately above the return tube nest from Oil-fired Furnace.
3. Exhaust gases from Oil-fired Furnace and ME; pass through the tubes, which are surrounded by boiler water.
4. Separate Uptakes provided for Exhaust Gases and Oil-fired Smoke.
5. Heavy Changeover Valves are fitted, to divert the gases straight to the funnel, when desired.

Alternative Boiler: (Alternative type Cochran boiler)

1. If Exhaust Gases and Oil fire can be used only one at a time, it is termed Alternative Boiler.
2. Double-pass, Alternative Cochran Boiler, can be oil fired and heated by exhaust gases alternatively.
3. Since both systems use the same Combustion Chamber, one system required being blank, while the other is in operation.
4. Only one Uptake required.

Economiser as Exhaust Gas Boiler:

1. In this system, a separate Exhaust Gas Economiser EGE is connected to an Oil-fired Auxiliary Boiler (or an Accumulator) by means of piping and a set of Circulating Pumps.
2. Heat absorbed from exhaust gas in EGE is transmitted by working fluid, to Auxiliary Boiler or Accumulator, from which steam is drawn for use.
3. Economiser unit cannot deliver steam, directly to steam range.
4. Straight gas lead from ME Exhaust Manifold, pass through EGE under the Funnel, and this arrangement permits the Auxiliary Boiler or Accumulator, to be placed in any convenient position in ER.
5. Inlets and outlets of piping coils are connected to External Headers [Distributing and Collecting], that are simply inserted in Exhaust Trunk way.
6. Water from Auxiliary Boiler or Accumulator is fed by Circulating Pump through
a Non-Return Valve into Distributing Chest or header and from it, water passes into Coils.
7. Water and steam from outlets of these Coils pass into Collecting Header, and then to the steam space of Auxiliary Boiler or Accumulator.
8. EGE Safety Valve is adjusted at slightly higher pressure than Safety Valves of Auxiliary Boiler; in order to ensure that Economiser operates in flooded condition at all times.

EGE out of order:

1. Isolate the EGE.
2. Wash down the economiser tubes and completely dried.
3. Drain all water content.
4. Start the auxiliary boiler.
5. Maintain low steam consumption.
6. Proceed to next port with suitable speed.
7. Write down damage report.

Exhaust Gas Boiler Safety Valve setting:

1. EGE safety valves to be set under full load steaming condition, if Surveyor delegates the responsibility to CE.
2. Setting pressure ≯ 3% above max: working pressure.
3. In doing so, EGE steam pressure control is done as follows:

EGE steam pressure controls:

1) Steam control: By providing Dumping Valve in by-pass system, to Condenser.
Excess steam can be discharged into Condenser.
2) Water control: By shutting the inlet valve to boiler coils.
3) Exhaust gas control: By controlling the Exhaust Gas Damper.

Boiler Safety Devices as for UMS status:

1. Flame failure: (Photocell shut down combustion system and gives alarm.)
2. Low and high water level: (Level is maintained by feed pump, controlled by float
operated on/off switch.)
3. Low and high Steam pressure: (If steam demand drops, high steam pressure will
shut down burner and/or ME speed reduced. Low steam pressure
alarm, will be given if there is fault in combustion condition)
4. Fuel temperature: (Deviation from set temperature range, cause burner to be shut
off and alarms given for both low and high temperature.)
5. Fuel pressure: (Low fuel pressure cause automatic controller to shut down
burner and alarms given.)
6. Smoke density: (Emitted smoke through uptake, being monitored and if deviate
from normal limit, shut down the system and alarm given.)
7. Air / fuel ratio: (Air register damper controller keeps correct ratio, and shut down
the system and alarm given on deviation.)
8. Draught fan failure: (Air supply fan failure operate audible and visual alarms.)
9. Very low water level: (Burner stopped and alarms given.)
10. Very high water level: (Burner stopped or ME slow down and alarms given to
avoid foaming and carry over.)
11. High flue gas temperature: (Burner stopped and alarms given.)

Safety Devices on Boiler:

1. Flame failure alarm
2. Low water level alarm.
3. Very low water level alarm and cut-off.
4. High water level alarm
5. Low steam pressure alarm
6. Low oil temperature alarm and cut-off
7. High oil temperature alarm and cut-off
8. Low oil pressure alarm and cut-off.
9. Force Draught Fan failure alarm and cut-off.
10. Power failure alarm.
11. Safety Valves.
12. Gauge Glass.
13. Easing Gear.

Mountings on Boiler:
1. Safety Valves
2. Easing Gear.
3. Gauge Glass.
4. Pressure Gauge.
5. Feed Check Valve.
6. Flame Eye.

Open-up Procedure:

1. Stop firing and cool down.
2. All steam valves tight shut.
3. Blow down until empty. [ Ship-side Cock opened first, then gradually open Blow-down Valve. When loud noise dies down and blow-down pipe becomes cold, boiler is about empty. Blow-down Valve shut and then shut Ship-side Cock.]
4. Easing Gear lifted.
5. Open Air Vent Cock, Salinometer Cock and Drain Cock of water Gauge Glass, to let air enter. Ensure no vacuum and only atmospheric pressure inside, before knocking in the manholes.
6. Slacken dog-holding nut of Top Manhole door, break the joint, from the place safe from blast as a safeguard against scalding, and then nut removed and door taken out.
7. When knocking in the Bottom Manhole door, use crowbar and stand back when breaking the joint, as there may be hot water left.
8. Mud holes and all other doors open-up for cleaning, both smoke side and waterside.
9. Allow the boiler to be ventilated before entry.

Boiler Internal Inspection: [For Survey]
1. After normal open-up procedure, allow the boiler to ventilate.
2. Initial internal inspection is done before cleaning, for general condition and
any special deposited area.
3. Plugged Blow-down hole to prevent choking.
4. Cover Manhole door’s landing surface to prevent damage.
5. Final internal inspection done after thorough cleaning:
a) Check level gauge connections for blockage.
b) Check securing system of internal pipes and fitting.
c) Hammer-test furnace, fire and stay tubes.
d) Check firebrick, casing, baffles and welding seams.
e) Tubes checked for leak, crack, distortion and bulging
f) Check fireside is clean, without soot.
g) Cleaning and inspection of Manhole doors, joint landing surfaces.
h) Use new joints.

Refitting Procedure:
After Internal Survey:
1. Remove plug at blow-down pipe.
2. Box back all manholes and mud doors with new joints, and refit all mountings.
3. Open Air Vent Cock, and boiler filled-up with water up to ¼ of Gauge Glass level. ( If hydraulic test is required, fill-up completely.)
4. Normal flash-up procedure follows.
5. Pressure setting of Safety Valves, under steaming condition, with Surveyor’s presence.

Safety Valves:
Function:

1. Must open fully at definite pressure, without preliminary simmering.
2. Must be still opening until pressure in boiler has dropped to a certain definite value, not more than 4% under set value.
3. Must close tight without chattering.
4. Must close tightly without leaking.

Setting of Safety Valves:

1. Take Standard Pressure Gauge for accuracy.
2. Fill up water up to ¼ of Gauge Glass level, and shut Main Stop Valve, Feed Check Valve.
3. Without Compression Rings, Hoods and Easing Gears, reassembled the Safety Valves with spring compression less than previous setting.
4. Raise boiler pressure to desired blow-off pressure.
5. Screw-down Spring Compression Nuts of any lifting valves, until all are quiet.
6. Adjust each valve in turn:
a) Slacken Compression Nut until valve lifts.
b) Screw-down Compression Nut sufficiently enough, so that when valve spindle is lightly tapped, valve returns to its seat and remain seated.
c) Measure gap between Compression Nut and spring casing.
d) Make a Compression Ring equal to this gap, and insert under Compression Nut.
e) Gag the Spindle of this Safety Valve, to prevent opening, while remaining valve is being set.
7. Remaining valve is again set and insert Compression Ring.
8. Remove gag and retest both valves to lift and close together.
9. Caps and Cotter Pins padlocked.
10. When the Surveyor satisfied the setting pressure, Easing Gear should be tested.
11. All Safety Valves set to lift at ≯ 3% above approved working pressure (design pressure).

Accumulation of Pressure:

1. Pressure is liable to rise after Safety Valves have lifted, caused by increased spring load due to increased compression.
2. This rise in pressure is known as “Accumulation of Pressure”. {OR}
3. Pressure rise in excess of Working Pressure is termed, “Accumulation of Pressure”.
4. Accumulation of pressure test is carried out to see whether this safety valve is suitable or not for this boiler. Pressure rise after safety valves have lifted, must not exceed 10% of working pressure.
5. Tested when safety valves are new or boiler is new or safety valves and boiler are new ones.

Safety Valve on EGE and Economiser:

1. Slightly higher set pressure than drum Safety Valves.
2. It is to ensure operation under flooded condition at all times.

Hydraulic Testing of Boiler:

Necessary condition:
1. Boiler internal inspection is not satisfactory.
2. Surveyor demanded.
3. After structural repairs of boiler.

Requirement:
1. Surveyor must be present.
2. Gag the Safety Valves.
3. Close all opening.
4. Blanks inserted at Main Steam Stop Valve and Gauge Glass.
5. Measuring tape placed around boiler to check bulging.
6. Deflection gauge placed in the furnace.
7. Remove lagging to check leak points.

Procedure:
1. Open vent cock, fill boiler with warm water completely, until water overflows from vent cock, and close the vent cock.
2. Attach force pump and test pressure gauge.
3. Apply water pressure, 1.25 times of approved working pressure, for not more than 10 minutes.
4. If satisfied, Surveyor will stamp on bottom front plate near the furnace.

Chemical Treatment:

Two ways of treating the water for boiler use:

1. External Feed Water treatments.
2. Internal Boiler Water treatment.

External Feed Water Treatment:
Purpose:
1. To reduce TDS in feed water.
2. To arrest Suspended Solid Particles.
3. To reduce Dissolved Gases.
4. To prevent feed water system corrosion, by maintaining correct pH value of feed water.

Treatments:
1. To reduce TDS, the best way is to use evaporated feed water.
2. To arrest Suspended Solids, use feed line filters.
3. To reduce Dissolved Gases, inject Hydrazine and maintain Hot Well temperature between 60~70°C to promote O₂ deaeration through hot well vent.
4. To prevent feed water system corrosion, use Salinometers on feed line or Evaporator outlet. Maintain pH value by dosing Hydrazine or Amine.

Internal Boiler Water Treatment:
Advantages:
1. Precipitate Calcium and Magnesium salts, into non-adherent, harmless sludge.
2. Prevent these salts, from baking on boiler heating surfaces.
3. Sludge is blown-down from boiler.
4. Treatments also remove Dissolved Oxygen, Dissolved Gases, and CO₂, to avoid their corrosive actions.

Treatments for Moderately Rated Auxiliary Boiler:
[Medium and Low Pressure Boilers]
(1) Phosphate Treatment:
1. AGK 100 or Adjunct B is used.
2. Combat scale-forming salts to form non-adherent sludge.
3. Give Alkalinity to reduce corrosion.
4. Form Iron Phosphate Film on internal surfaces, as protection against corrosion.

(2) Caustic Soda Treatment: [NaOH]
1. Maintain correct pH value and required Alkalinity.
2. Precipitate scale-forming Permanent Hardness Salts. [Chlorides and Sulphates of Calcium and Magnesium: They are in Acid nature. ]
3. Remove Temporary Hardness Salts. [Bicarbonates of Calcium and Magnesium: They are slightly in Alkaline nature.]
4. Excess concentration of NaOH may cause Caustic Cracking of metal.

(3) Soda Ash Treatment: [Na₂CO₃]
1. Precipitate scale-forming Permanent Hardness Salts, (Non-Alkaline Hardness Salts) as Calcium Carbonate, CaCO₃.
2. Produce NaOH, to give required Alkalinity.

(4) Dissolved Oxygen Treatment:
1. Two chemicals, Hydrazine N₂H₄, and Sodium Sulphite Na₂SO₃ are used to remove dissolve O₂.
(5) Liquid Coagulant Treatment:
1. High molecular weight, colourless solution, likes Sodium Aluminate or Starch is used.
2. Coagulate oil droplets and Suspended Solids, and settle them at low points.
3. They can be Blown-down.

(6) Blow-Down Treatment:
1. Integral part of water treatment program, as it removes solids, which are results of chemical conversion of salts and impurities in water.
2. Surface Blow-down or Scumming is quick removal of solids, without wasting feed water.
3. Bottom Blow-down is vital, when solids become dense, heavy and remain at boiler bottom, despite circulation.
4. Daily short blows of top and bottom are necessary.

Boiler Laying up Procedure:
(Boiler may be laid up wet or dry.)

Wet Method:
1. When laid up in warm climate, boiler is filled with water until it comes out from air vent.
2. Then the boiler is sealed off.

Dry Method:
1. Boiler is emptied and cleaned thoroughly on both fire and waterside.
2. Corroded parts, wire brushed and coated with anti-corrosive paint.
3. Shallow metal trays filled with quicklime should be placed in both water and fire space.
4. Then boiler is closed up airtight.

Proper Maintenance of Boiler:

Water Side:

  • Daily boiler water test.
  • Boiler water treatment.

Gas Side:

  • Regular cleaning.

Combustion System:

  • Fuel pressure, temperature and viscosity correct values maintained.
  • Burner maintenance.
  • Air register, Air damper and forced draught fan.

Caustic Cracking or Embrittlement of metal:

1. Caused by excess concentration of Sodium Hydroxide, NaOH [Caustic Soda] in boiler water, and the material under stresses.
2. Ratio of Na₂SO₄ to NaOH should be maintained 2 : 5.
3. Caustic Soda is used for boiler water treatment, to maintain correct pH value and required alkalinity, so excess concentration should be avoided.
4. Excess concentration of NaOH may be from Overdosed Chemical and Leakage.
5. Damage occurs to riveted seams, tube ends and bolted flanges.

To prevent Caustic Embrittlement:

1. Sodium Sulphate, Na₂SO₄ should be dosed, to give protective layer.
2. Ratio of Na₂SO₄ : NaOH should be maintained at 2 : 5

Turn Down Ratio of Burner:

1. The ratio of maximum to minimum oil throughput of the burner.
2. In case of pressure jet burner, this can be stated in terms of square root of the ratio of maximum to minimum oil supply pressure.
3. Large Turn Down Ratio of up to (20: 1) is available with blast jet burner, without having resort to unduly high pressure.

Foaming:

Formation of thick layer of steam bubbles, on top of water surface inside boiler.
Priming: Rapid carry-over of large amount of water, in steam as it leaves the boiler.
Carry-over: Carry-over of small amount of water, in steam as it leaves the boiler.

Causes:
1. Higher water level than normal
2. High amount of TDS, total dissolved solids
3. High amount of suspended solids
4. Contamination by oil and other organic substances
5. Forcing the boiler

Effects:
1. Water hammer
2. Contamination and scaling
3. Fluctuation of working water level

COC ORAL EXAM PREPARATION (PART- 4) – LUB OIL & FUEL OIL

Lubricating Oil

Viscosity:
1. A measure of internal resistance to flow.
2. Viscosity of an oil changes with temperature, falling when temperature rises and vice versa.
3. For crankcase oil, viscosity is between 130 – 240 Sec. Redwood No. 1 at 60°C.
4. For cylinder oil, viscosity is 12.5 – 22 Cst.

Viscosity Index, VI:
1. The rate of change of viscosity of an oil, in relation to change of temperature.
2. Oil of low VI has greater change of viscosity with change in temperature,
than the oil of high VI.
3. For crankcase oil, VI is between 75 – 85; For cylinder oil, VI is 85.
4. Highest VI of mineral oils is about 115 and with special additives, this may be raised to about 160.
5. Hydraulic oils, used in remote control hydraulic circuits must have very high VI; otherwise erratic response to the controls can be troublesome. (Telemotor hydraulic system oil has VI of 110.)

Pour Point:

  • Lowest temperature at which an oil will barely flow.
  • Pour point indicates that oil is suitable for cold weather or not.
  • or crankcase oil, Pour Point is, – 18°C.

TAN and TBN:
1. TAN is the ability of an oil, to react with basic reagent, which indicates the acidity
expressed as TAN.
2. TBN is the ability of an oil, to react with acidic reagent, which gives an Alkali figure, the TBN.
3. Expressed in milligrams of KOH required to neutralise one gram of sample oil, for both TAN and TBN.
4. For crosshead type engine crankcase oil: TBN is 8 mg KOH/gm of oil.
5. For Trunk type engine using HO, crankcase oil: TBN is 30 mg KOH/gm of oil.

Detergency/Dispersancy:
1. Deposits occur in engine crankcase or ring zone, due to semi-solid precipitation from LO.
2. High temperature effect accelerates the rate of such deposition.
3. To reduce formation of such deposits, oil is treated with Detergent/Dispersant Additives, for keeping the system clean and trouble-free.
4. When using conventional mineral oils, these deposits block exhaust passage and prevent free movement of piston rings.
5. Addition of Detergent Additive prevents deposition of such deposits and washes them away with LO.
6. By addition of Dispersant Additive, tiny particles are carried in colloidal suspension, and dispersed evenly throughout the bulk of oil.
7. Detergent/Dispersant Additives are complex chemical compounds, such as metallic based Sulphonates, Phosphonates, Phenates and Salicylates.

Function of Lubricant:

1. Reduce friction.
2. Remove heat.
3. Flush away contaminants.
4. Protect corrosion.
5. Dampen noise.
6. In some case, act as sealant.

Types of Lubrication:

1. Hydrodynamic lubrication.
2. Boundary lubrication.
3. Hydrostatic lubrication.
4. Elasto hydrodynamic lubrication.

Hydrodynamic lubrication: 
1. Moving surfaces are completely separated by continuous unbroken film.
2. Lubricant, because of its viscosity, is drawn between the surfaces and builds up a film, by the action of moving parts.
3. Thickness of film: 0.025 – 0.10 mm.
4. Essential requirement is formation of oil wedge between the surfaces.
5. Lubrication for Journal Bearing, Bottom End Bearing, Tilting Pad Thrust Bearing.

Boundary lubrication.
1. It exists when full fluid film lubrication is not possible.
2. High friction between surfaces, and a degree of metal to metal contact occurs.
3. Lubricant oil film decreases, until asperities of mating surfaces touch.

Hydrostatic lubrication:
1. A form of Hydrodynamic lubrication, but instead of being self-generated, it is supplied from external source of oil under pressure, from a pump.
2. Lubrication for Crosshead Bearings, with attached pump.

Elasto-hydrodynamic lubrication:
1. Applied to line contact or nominal point between rolling or sliding surfaces, as in ball bearings, roller bearings and gear trains.
2. Thin film lubrication limits metal to metal contact.
3. Elastic deformation of metals occurs, and there is high-pressure effect on the lubricant.

Contaminants in LO:

(1) Water:
1. Owing to condensation of water vapour in crankcase.
2. Leakage from cooling water system for cylinder or piston.
3. Combined with oil in the form of emulsion.
4. Combined with sulphurous products of combustion to form Sulphuric Acid, in trunk engine.

(2) Fuel Dilution:
1. Presence of fuel oil in crankcase oil is indicated by reduction in viscosity and flash point.
2. Result from poor atomisation of fuel injectors.

(3) Oxidation Products:
1. Mineral oils react with oxygen in air and form oil-soluble organic acid, lacquers, resin and sludge, depending upon temperature and degree of contact with air.
2. Accelerated by contact with copper and iron, which act as catalyst.

(4) Fuel Combustion Products:
1. Mainly acids and incompletely burnt fuel form sludge and deposits.
2. Inorganic acids from combustion of high-sulphur residual fuel.

(5) Foreign Mineral Matters:
1. Rust and scales from storage tanks and pipes, etc.
2. Dust from surrounding atmosphere.
3. Wear debris from lubricated surface [not entirely hydrodynamic], and from corrosion of cylinder liner.

(6) Biological contamination:
1. Associated with ‘wet oil’ caused by leakage from cooling system.
2. It causes formation of organic acids, sludge and additive depletion, corrosion of shaft and bearings.
3. If happened, complete oil change may be necessary, thorough sterilisation and cleaning out of cooling system, and leakage to be stopped.
4. Addition of biocides to both oil and water, helps.

Symptoms of LO Contamination:

1. Increased Sump sounding (severe SW contamination).
2. Change in pressure and colour (Emulsification of oil, with water and residues of treated cylinder oil from diaphragm or scrapper box leakage).
3. Change in pressure (Reduction in viscosity and flash point, due to fuel oils.)
4. Frequent choking of filters due to sludge formation and Additive depletion, due to biological contamination.
5. Darkened oil colour and yellowish colour film on surface, pungent smell & sludge formation, due to microbial degradation.
6. Particles of rust and scales, mostly ferrous, trapped in magnetic filter (Corrosion of shaft and bearings, due to water, fuel combustion products.)
7. Wear debris, and welding spatter trapped at magnetic filter (Contamination of foreign mineral matters.

How to remove contaminants:
1. Filtering – removed large oil insoluble matter.
2. Gravity separation – heavy matters, sludge and water.
3. Adding special additives – reduce acids, sludge, finer oil insoluble matter.
4. Centrifuging – Sludge, foreign matter and water.
5. Water washing – only for straight mineral oil or oil without additives, can remove acids.

Water washing:
1. It can be carried out on straight mineral oil but not for detergent / dispersant type oil
2. The purpose is to remove acids, salts and other impurities from the oil.
3. Water should be injected before purification at a rate of 3% to 5% of oil flow.
4. Oil temperature should be around 75˙C and water temperature about 5˙C higher than oil temperature.

Batch purification:
1. If oil is contaminated with strong acids, high insoluble contents or water, batch purification of the entire charge oil should be done.
2. In port, the entire charge oil is pumped by purifier or circulating pump into Renovating Tank, fitted with steam heating coils.
3. Allowed to settle for at least 24 hours at about 60˙C.
4. Water and sludge must be periodically drained out.
5. Then oil is passed through the purifier at its optimum throughput and pumped back to Sump Tank.
6. During the time when the sump tank is empty, its interior should be cleaned and examined.
7. This should be done at least once a year.

Throughput of a purifier: The best purification result is obtained if oil is kept inside the bowl as long as possible, i.e. throughput should be as low as possible and also more frequent desludging once every hour.

If LO is contaminated with SW:

1. When sump oil is contaminated with SW, find sources of leakage [may be from LO cooler during ME stoppage] and rectified.
2. In port or while ME is stopped, transfer contaminated oil through purifier or transfer pump into Renovating Tank, settled for at least 24 hours at about 60°C, and water and sludge drained out periodically.
3. Oil passed through purifier at 78°C with optimum efficiency, and pump back to Renovating Tank.
4. When Sump Tank is empty, interior cleaned and examined.
5. Purified oil sent to Laboratory and tested.
6. During this time, new oil should be used.
7. Oil should be reused, if Lab results recommended that it is fit for further use.
[Straight mineral oil: 3% water washed. Additive oil: 1% water washed.]

L.O. for Crankcase Viscosity 130 – 240 Sec. Redwood No. 1 at 60’C.
VI 75 – 85 Pour pt. – 18’C Closed flash pt.220’C
TBN (trunk type) 30 mgKOH/gm of oil
TBN ( X-Head Type ) 8 mgKOH/gm of oil.

Water in LO
Effects:
1. Can form Acids.
2. Can cause corrosion on m/c parts.
3. Microbial degradation. [Reduce centrifuging efficiency; promote local pitting and corrosion].
4. Reduce load carrying capacity.
5. Reduce L.O. properties, and TBN of oil.
6. Form sludge due to emulsification.
Remedies:
1. Proper purification with minimum throughput.
2. Batch purification if heavy contamination.

Maximum Allowable % of water in LO
1. For crosshead engine, < 0.2% is satisfactory. 2. If water content exceed 0.5 ~ 1.0%, immediate action should be taken. If > 1%, engine can be damaged.
3. For trunk type engine, < 0.1% is satisfactory. If > 0.5%, immediate action should be taken and
it is maximum permissible content.

LO tests onboard:

Tests carried out on used diesel crankcase oil:
1. Viscosity {changes caused by dilution with fuel oil}.
2. Closed flash point {changes caused by dilution with fuel oil}.
3. Insoluble
4. Water content
5. Acidity.

(1) Viscosity determination:
–  Viscosity and closed flash point will fall by fuel oil contamination.
–  Changes in these values are a measure of dilution, and up to 8% contamination can be tolerated.
Three Tubes Rolling Ball Viscometer:
1. Assume that system oil is SAE 30.
2. One tube filled with minimum safe viscosity, SAE 20.
3. One tube filled with maximum safe viscosity, SAE 40.
4. Last tube filled with test sample.
5. All tubes placed in warm water, until at same temperature.
6. All tubes placed on tilted board and inverted, so that internal hollow balls rise to surface, with different time taken.
7. If time taken for test sample is between upper and lower limit oils, this sample oil is fit for further use.

(2) Insoluble Content:
» Insoluble are soot, dust, metallic particles, asphaltene, oxidation products, and products of deterioration.
Blotter Test:
1. Single drop of sample oil is released from a given height onto a sheet of Special Filter Paper.
2. The result is compared with Standard Test Paper, of similar oil with known varying insoluble content.
3. Test oil should be below the upper limit:
Upper limits of insoluble are: 1.00% to 1.5% for Straight Mineral Oil,
5% for Detergent/Dispersant type Oil.
(3) Water and other contaminants by:

Crackle Test:
1. Pour a known amount of sample oil into a test tube.
2. Hold the test tube over small spirit lamp, shaking it while doing so.
3. If there is no crackling, the oil is dry.
A slight crackle indicates a trace of water.

(4) Acidity Determination:

1. Tested by extracting the acids from sample oil, by means of shaking with known amount of distilled water, in a test tube.
2. Acidic extract is placed on a watch glass, with Indicator Solution of known strength.
3. The mixture is drawn into a glass tube, and compared with Colour Standards, each representing a known pH value. Sample can be determined quite accurately.

Microbial Degradation:

  • If free water is present in crankcase, micro-organisms may grow, at oil water interface, by consuming hydrocarbons in oil.
  • Infestation at early stage may not be harmful but in case of severe infestation, corrosion within machinery parts may arise.
  • Complete oil change is necessary.

Indication:

1) Darkened oil colour and yellowish colour film on surface.
2) Pungent smell
3) Sludge formation.

Poor quality fuel:

High pour point.: Needs extra heating for storage tank.
High density: Causes purification difficulties.
High viscosity: Pumping difficulties and more heat required getting suitable injection
viscosity at injector.
Low cetane number. Late injection and after burning. It is considered as poor fuel, if C  37 .
Abrasive group: (ash, silica, nickel, catfines): Cause wear on cylinder liner, piston rings, ring
grooves and fuel injection equipment.
Corrosion group: (Sulphur, Vanadium, Sodium): Low temperature corrosion due to sulphur.
Acid dew point is 120 – 160°C
High temperature corrosion due to Vanadium, Sodium and Sulphur
at 460 – 570°C
Corrosion or vapour locking at fuel injection equipment, due to water.
Fouling group: (catfines, CCR): Slow burning due to Asphaltine, combustion space fouling
and T/C fouling due to CCR.

Flash Point:
1. Lowest temperature at which an oil will give off sufficient flammable vapour, to produce a flash when a small flame is brought to the surface of the oil.
2. Minimum flash point for on-board use is 60°C.
3. Fuel storage temperature must be kept at least 14°C lower than its flash point.
4. Average closed flash points: Petrol – 20°C: Paraffin 40°C: Diesel Oil 65°C:
LO 220°C: 70 cst Fuel Oil 71°C: Heavy Oil 100°C:

Pour Point:
1. Lowest temperature at which the oil barely flow.
2. It is just above the lowest temperature at which liquid flows under its own weight.
3. It must be low, otherwise fuel tends to solidify and due to poor heat transfer property, fuel cannot be returned to its original state by heating.
4. Fuel storage temperature must be kept at least 10°C higher than its pour point.
5. At least 40 – 50°C higher than its pour point, for cold weather condition.

Homogenizer:
1. It is a device to create stable oil and water emulsion, which can be bunt in boilers and diesel engines.
2. This emulsion can burn more efficiently and reduce solid emission in exhaust gas.
3. It can reduce catfines into finely ground particles, which do not harm.

Bunkering Operation

How to order bunker:

1. Take essential data from master, such as distance to go with average speed, river passage, pilotage, port stay, etc. To check ROB.
2. Estimate HO and DO consumption based on weather, wind and current condition, running hours of AEs auxiliary boiler and ME.
3. Estimate the 3 days reserve, considering unpumpable quantity, bunker allowance or bunker margin.
4. Calculate the capacity to receive, bunker amount, type of bunker, HO, DO or LO.
5. Bunker should be allowed 85% of tank capacity.
6. Arrange not to mix with remaining onboard fuel.

Total required bunker from port to port = {Distance to go with average speed + River
Passage + Pilotage + Port Stay + 3 Days Reserve }

Bunker to be ordered: = { Total required – ROB }

CE’s Responsibility during Bunkering:
CE is overall in charge of bunkering.

Responsibilities are:

1. Fire prevention
2. Oil pollution prevention
3. Calculation
4. Recording and informing.

Discuss at Bunkering Meeting about: Quantity / Bunkering Sequence / Distribution Plan.
Make preparations for both Deck and Engine Department, in accordance with pre-bunkering checklist.
Prepare all necessary papers as per local regulations.

Fire Prevention:

1. Prohibit naked light and smoking around bunker area.
2. Place portable fire extinguisher at bunker point.
3. Bunker oil flash point ≮ 65°C, as a rule.
4. Ensure no oil leakage.

Pollution Prevention:

1. Clear overflow tank and top up settling and service tank.
2. Clean System filters, sight glass, and pressure gauge in good order.
3. Ensure bunker system valves in good order, and the correct valves have been opened.
4. Take all soundings of fuel tanks, and calculate the amount to be put into each tank.
( 85% of tank capacity is maximum. )
5. Explain bunkering sequence to all engineers.
6. Check security of hose coupling, and one responsible engineer to be stand-by at bunker station to watch break or spill at hose connection.
7. Agree the pumping rate or pressure with pump man or barge master, remembering that a burst hose can cause pollution. Discuss slow down operation and emergency stop procedure.
8. Make good communication between bunker point, barge or shore supply, and tank control station.
9. Leakage or overflow of oil to deck strictly prevented. Saw dust, OSD, and rags, ready at bunker point.
10. Duty officer to be informed, the amount to be bunkered and expected time of the work.
11. Plugged all deck scuppers.
12. Maintain the upright position as possible as.

 

For Calculations:

1. Take all soundings of fuel tanks, before and after bunkering.
2. Take fore and aft draughts, before and after bunkering.
3. Take soundings of barge or to check flow meter reading, before and after bunkering.
4. Record the oil temperature.
5. Calculate corrected sp.gr. at measuring point temperature, SGc.
6. By multiplying SGc with total volume, obtained from sounding table, total amount of bunker in tons will be obtained.

Bunker Barge Arrival:

1. Record exact time of barge arrival and departure.
2. Check local supplier’s paperwork, to ensure that specification and quantity ordered is correct.
3. Check for correct specification, and compatibility tested, by using a test kit.
4. Check water content of bunker is at acceptable level.
5. Ensure that onboard fuel handling equipment is adequate and serviceable at all times.

Bunkering:

1. Start bunkering at slow rate, and then raise the pumping rate.
2. Always check and witness the flow meters, tank gauges and tank dips, before and after delivery, to ensure that the right quantity has in fact been supplied.
3. Random checks to ensure correct specification of oil being supplied during bunkering.
4. Take a continuous drip sample. Compatibility test of bunker carried out.
5. Always insist on being given a sealed sample of bunkers delivered, which should be witnessed and signed by both parties.
6. When 80% of total capacity reaches, pumping rate slow down and final topping up done.

After Bunkering:

1. Record the time and read flow meter on bunker boat or on shore.
2. All filling valves kept open, until final air blowing is completed.
3. Remain hose connections until correct quantity of oil has been received after calculation.
4. Then close bunker main valve, system valves and individual tank valves.
5. Take final soundings and bunker temperature from both ship and barge to calculate actual amount.
6. When calculating the bunker received, the ship’s trim and temperature of the oil must be taken into account.
7. Both party signed on sample bottles and sent to laboratory. The statutory sample to be kept in sample store and retain it for 12month.
8. Inform duty officer, starting and stopping time, amount of bunker received and tank soundings, for stability calculation and custom claiming purposes.
9. Make entries into ORB, Sulphur record book and Logbook.
10. BDN to be collected from supplier and file it properly to retain it for 3 years.
10. Prepare Bunker Report and sent to HO.

FO Overflow while Bunkering: [Action taken by CE.]

1. Stop pumping of fuel immediately.
2. Report to Master and contact Port Authority or persons concerned, about oil pollution incident.
3. Detail description of actions taken immediately by crew, using equipment from Oil Spill Locker to reduce and control the oil flow.
4. Arrange point of contact onboard, for co-ordinating shipboard action with local authorities, in combating pollution.
5. Make entry into ORB, date, time, place and amount of overflow.

Bad fuel:

1. Bunker should be received in empty tank and made segregated.
2. During bunkering, compatibility test should be done.
3. Sealed sample sent to laboratory for analysis.
4. Maintain storage temperature well above pour point. (About 40’/50’C under coldest climate condition.)
5. Settling tank temperature maintained about 14’C below flash point to improve gravitational separation. Regular drain out of water and impurities.
6. Fuel transfer lines steam traced, and transfer pump suction filter cleaned.
7. If necessary, dose chemicals, e.g. Gamma Break- Unitor, into storage tanks ( DB tanks) by using dosage pump for chemical.
8. Regular cleaning of coarse filters.
9. Two purifiers run in parallel, to get enough fuel for engine, with optimum throughput and correct heating temperature (98’C). Gravity disc, carefully chosen. If necessary, double stage centrifuging will be done with purification and clarification in series.
10. Maintain correct service tank temperature. Dose some chemicals, to improve combustion efficiency. (Duel Purpose Plus, Unitor)
11. Maintain correct oil temperature, to get suitable viscosity at injectors,
( 10 ~ 18 Cst.). Fuel outlet from heater, controlled by Viscotherm Unit.
12. Steam tracer lines correctly heated, up to injector.
13. Maintain correct working temperature of engine, to prevent hot and cold corrosion due to Vanadium and Sulphur attacks.
14. Check engine performance by taking indicator diagram.
15. If damage occurred due to bad fuel, prepare for insurance claim.

Compatibility:
1. Ability of two fuel to be blended together without precipitation of sediments, such as asphaltine and sludge, etc.
2. Due to asphaltine and sludge, it can cause choking of filters, overloading of purifier and immobilisation of vessel in severe case.

Remedies: For Incompatibility:
1. Keep fuels in empty tank and segregated.
2. Always carry out compatibility test when bunkering.
3. Incorporate homogenisation system to completely mix incompatible fuel components prior to injectors.

Compatibility Test:
1. Pour 40 ml of sample into test tube. (20 ml for each fuel)
2. Add reagent of white spirit up to 80 ml. (ē 40 ml white sprit)
3. Then the mixture is mixed well.
4. One drop of mixture is deposited on chromatographic paper and allowed to dry at room temperature.
5. Then test drop is compared with five standard spots.
Spot 1 ~ 2 indicate compatible fuel.
Spot 3 ~ 5 indicate incompatible fuel.

Requirements for the use of high viscosity fuel:

1. Bunker tank-heating systems capable of maintaining fuel temperature about
40-50’C higher than Pour Point under the coldest climate condition.
2. Exposed bunker transfer pipes insulated and trace heated.
3. Treatment plant capable of purifying/clarifying high density fuels.
4. Engine preheaters designed to achieve recommended injection viscosity.
5. Trace heated and pressurised engine fuel system, allowing manoeuvring on residual fuel.
6. Main and auxiliary engine designed to burn high viscosity fuel oil.

Effects of Bad Fuel Oil:

1. Too much sludge formation in DB tank.
2. Frequent fuel line filter blockage.
3. Upsetting purifier.
4. Premature wears of fuel pump.
5. Carbon trumpet formation and leaky FV.
6. Excessive wears and cold corrosion of cylinder liner.
7. Excessive carbon deposits in piston rings.
8. Hot corrosion attack on Exhaust valve.
9. Choked turbine nozzle rings and broken blades.
10. Excessive carbon deposits on EGE.

Bunker Specifications:
Includes: Name of vessel, Port of bunker, Date of delivery, Product name, Temperature of product, Sulphur Content,
Quality:
1. SG at 15°C
2. Viscosity at 50°C
3. Sulphur content % by weight
4. CCR % by weight
5. Flash Point [closed] °C
6. Pour Point °C
7. Water content % by volume
8. Sludge / Sediment % by weight
9. Cetane No.
10. Vanadium in ppm.

Bunkering:
1. Slow rate and record.
2. Take soundings.
3. Random check
4. Continuous drip sample.
5. Compatibility test
6. Slow down when 80% is reached.
7. Remain v/vs opened until after air blow.
8. Remain hose connection until after calculation.
9. Take sealed sample
10. Close all valves.

Viscotherm Unit:
A device to adjust the viscosity of oil to get desired value, which is essential for correct atomisation and combustion of engine.

Operation:
1. Constant quantity of oil is taken from the flow and fed into capillary tube by means of motor operated gear pump through reduction gear.
2. Oil flows through capillary tube under laminar condition and pressure drop across the tube is measured by DP cell and its signal is directly proportional to oil viscosity. A transducer is incorporated with DP cell.
3. Signal given by DP cell is compared with a set value and any deviation can cause
drive signal to adjust pneumatic control steam inlet valve to oil heater.
4. Normally the required injection viscosity is 10 ~ 18 Centistrokes and required value is set at transducer.

VIT:

1. Load-dependent start of fuel injection control system.
2. VIT mechanism automatically change the fuel injection timing, according to load,
to get maximum combustion pressure (Pmax) at engine load between 85% ~ 100%.
3. Reduction in SFOC is about 2.0 gm / bhp / hr at 85% engine load.
4. VIT fuel pump incorporates variable injection timing with optimised fuel economy,
at part load.
5. Expansion Ratio is increased.
Maximum Pressure
Expansion Ratio =
Pressure at the start of Exhaust Blow-down

6. Required fuel viscosity at engine inlet is 10 ~ 20 Cst.

In other words:
1. If an engine running at prolong period at reduced load, lower air temperature after compression, will cause increase in ignition delay of injected fuel, subsequently causing knocks and poor combustion.
2. This problem can be reduced by adoption of VIT system, to advance the start of injection, then allowing the same Pmax, at part load.

Operation of VIT: [ Valve control type: Sulzer RTA ]

1. Fuel Quality Setting [FQS] lever is used for manual adjustment of VIT mechanism to alter valves timing, according to ignition quality of fuel used. [If poorer quality fuel is used at same valve timing, Pmax will drop, and with better ignition quality fuel, Pmax will rise.]
2. VIT mechanism is linked to Governor Load Setting Shaft and built-in cam system, which is positioned by FQS lever.
3. This mechanism controls the timings of Suction Valve closure (beginning of delivery) and Spill Valve opening (end of delivery) through linkages simultaneously.
4. Hence, fuel injection timing, Pmax, and fuel delivery to injectors, are controlled load-dependently.

Thermal Cracking:

1. Atoms within hydrocarbon molecule are excited by heating, thus lighter fraction of molecule breaks-off and condensed.
2. Remaining portions of original molecule then unite to form more heavier molecule.
3. Thermal cracking produces Asphaltene, which has heavy hydrocarbon molecules,
causing slow burning in fuel combustion.

COC ORAL EXAM PREPARATION (PART- 2) – SURVEY & CERTIFICATION

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Image Credit: Marinelink

Survey:

Authorised independent examination, investigation, and inspection, measuring or testing of ship structure, machinery and equipment, done and supervised by Surveyors appointed by regulatory or commercial organisations.

Classification Societies:
They are third party independent bodies e.g. ABS (American Bureau of Shipping), BV (Bureau Veritas), LR (Lloyd’s Register), ClassNK (Nippon Kaiji Kyokai), DNV (Det Norske Veritas), GL (Germanischer Lloyd).

Their functions:
1. To ensure that ship is soundly constructed and the standard of construction is maintained.
2. Carried out Statutory Survey on behalf of the Administration regarding the ship safety and prevention of pollution of marine environment.

Classed ship:

  •  A ship, which is built in standard and maintained under rules and regulations of Classification
  • For a ship to be entitled to a class, Classification Society issues a Classification Certificate after carrying out Classification Surveys.
  • Classification Certificate confirms that the ship has both structural and mechanical fitness for their intended services.

Maintaining the class:
To maintain a ship in the class:
–  The owner must carry out regular surveys of hull, machinery and equipment.
–  Carry out repairs necessary from time to time, under the supervision of Class Surveyors.

Statutory Survey:
–  Carried out by Administration regarding the safety of the ship, sea worthiness and pollution, in accordance with national and international rules.
–  Issued a certificate, this is essential to the ship’s ability to trade.
–  If Statutory Survey is not certified, the ship can be detained.

Statutory Surveys are:

  • International tonnage survey
  • International load line survey 5 years interval
  • Cargo ship safety construction survey 5 years –
  • Cargo ship safety equipment survey 2 years –
  • Cargo ship safety radio survey 1 year –
  • Marpol IOPP & IAPP survey 5 years –

Classification Survey:

  • Carried out by Classification Surveyor, to ensure that the ship has both structural and mechanical fitness, for intended voyage, in accordance with the class requirements.
  • A classification survey is a visual examination that normally consists of:
    –  an overall examination of the items identified in the Rules for survey;
    –  detailed checks of selected parts, on a sampling basis;
    –  witnessing tests, measurements and trials where applicable.

Difference bet: Statutory Survey and Classification Survey:

  •  Statutory surveys are not assessing or measuring something for a client.
  • Statutory survey will inspect something against a set standard or law.
  • On completion of this survey, the ship is issued with a certificate, which is essential to the ship’s ability to trade.
  • Class cannot go to the ship unless requested by the owner, or unless the ship is detained by the Port State Control.

Why Classification Societies sometimes issue the Statutory Certificate?

  • Sometimes Administration delegates the authority, to the Classification Society to inspect and issue Certificates, on their behalf, regarding statutory requirements.

Port State Control:

1. Port State Inspection is a particular form of Statutory Survey.
2. Intention of Survey is to check that, ships flying the Flags of States comply with the Requirements of the Conventions.
3. When these ships are in Ports of States, Port State Authority has control over the ships in port, and has rights to inspect the followings, in order to avoid Substandard Ships:
– Safety Equipment.
– IOPP & IAPP Certificate.
– Oil Record Book.
– Sewage Treatment Plant.
– MARPOL Equipment.

For PSC purposes, Port Authorities will apply in general, the following Instruments.
ILL 66, SOLAS 74, MARPOL 73/78, STCW 78, COLARG 72 and ILO 76.

4. A Surveyor representing the Authority of the Government carries out the Port State Inspection.

Preparation for Port State Control Inspection: [As a CE]

  •  IOPP, IAPP, IEE Certificates for MARPOL
  • Load Line Certificate
  • SOLAS Certificates
  • STCW Certificates, kept ready.
  • Safety Equipment prepared for testing and inspection.
  • MARPOL Equipment prepared for testing and inspection, such as:
    – OWS operation and alarm test.
    – Incinerator tested and kept ready for demonstration, and alarm test.
    – Sewage Treatment Plant, in good order, and dose chemicals.
    – Tank top near OWS and Bilge Pumping Station kept clean.
    – Bilge overboard discharge valve, tightly closed and kept under lock and key.
    – Update and attach ORB, with photocopies of MARPOL Certificates, original Oil Disposal Receipts, and Dirty Oil and Sludge Piping Diagram.

Flag State control:

1. Flag State or Administration has responsibilities that the ships built to their flag, comply with the Requirements of the Conventions, in construction and upkeep afterwards.
2. Government body carried out Surveys and issued Certificates relating to safety of the ship, sea worthiness and pollution.
3. Flag State Control is limited to ensure that valid Certificates are onboard:

  1. Passenger ship safety certificate Validity 1 year.
  2. Cargo ship safety construction certificate 5 years
  3. Cargo ship safety equipment certificate 2 years
  4. Cargo ship safety radio certificate 1 year
  5. International load line certificate 5 years
  6. MARPOL IOPP & IAPP certificate 5 years
  7. International sewage pollution prevention certificate (ISPP)  5 year.

Preparation for Entering a Stringent Port:

  • In Port State Control system, inspections are done at the port, in order to avoid Substandard Ships.
  • For PSC purposes, Port Authorities will apply in general the following Instruments.

1. International Convention of Load Line. ILL 66
2. International Convention for Safety of Life at Sea. SOLAS 1974.
3. International Convention for the Prevention of Pollution from Ships.
MARPOL 1973/78
4. International Convention on Standard of Training,
Certification and Watch Keeping for Seafarers. STCW 1978.
5. Convention or the International Regulation for Prevention of Collision at Sea.
COLARG 72
6. Merchant Shipping (minimum standard) Convention. ILO 1976

Before entering the port, prepare the following in general:

1. Certificates and Documents prepared.
2. ORB properly entered and updated.
3. Sludge formation should be compared with 1% of voyage fuel consumption.
4. Receipt for sludge and waste oil disposal to shore facility, attached to ORB.
5. ORBs retained for 3 years after date of last entry should be onboard.
6. IOPP Certificate has validity.
7. OWS alarm tested, discharge valve closed, spare filter onboard, tank top near OWS cleaned.
8. ODM tested for 15ppm alarm, and automatic stopping device.
9. USCG Notice posted especially near OWS and bilge pumping station.
10. Boiler not to emit black smoke.
11. Incinerator prepared for demonstration:

  • Waste oil tank, drained-off water and heated up to 80 – 90˙C.
  • Photocell, pilot burner and waste oil burner of incinerator removed and cleaned.
  • Flame failure, high flue gases temperature, and force draught fan failure alarms tested.
  • Line filter for waste oil line, cleaned.
  • Incinerated ash collected to show to Surveyor, or if disposed to shore facility, receipt attached to ORB.

12. Fire extinguishers and fire detection system, CO₂ alarms system, tested.
13. Check Sewage plant.

Periodical Survey: Mainly consists of Annual Survey and Special Survey.

Annual Survey (machinery):

  • General Inspection of conditions of the whole machinery and equipment.
  • At each Annual Survey between Special Surveys, main and auxiliary machinery are generally examined, and placed in satisfactory running condition.
  • If necessary, some of the machinery or parts are to be opened-up for the surveyor to examine.
  • Survey items include steering arrangement, windlass, weather decks, watertight bulkheads, doors, fire equipment, hatch ways, etc: (hull survey items).

Special Surveys (machinery):

  • Thorough Inspection of the whole machinery and equipment
  • Including open-up inspection of machinery and equipment, their performance tests and inspection of electrical installation.
  • Main and auxiliary machinery are subjected to Special Survey, at intervals similar to those for special surveys of the hull, i.e. every 4 years, in order that both may be recorded approximately at the same time at each Special Survey.

1. All openings to sea, including sanitary and all overboard discharges together with cocks and valves to be examined internally and externally.
2. Fastenings to the shell plating are to be renewed, if surveyor recommends.
3. Pumps and pumping systems including valves, cocks, pipes and strainers are to be examined.
4. Shafts, except propeller shaft, bearings and line shafts to be examined.
5. Foundations of main and auxiliary machinery to be examined.
6. Cylinders, cylinder heads, valves and gears, fuel pumps, scavenging pumps, superchargers, pistons, crossheads, connecting rods, crankshaft, clutch, reversing gears, air compressors, intercoolers, and such other items covered by CMS system.

CMS/ CSM:

  • A Special Survey carried out on a planned schedule, within a circle of 5 years, at the request of the owner, and upon approval of the proposed arrangement
  • Approximately 20% of the surveyable machinery items shall be examined each year.
  • Completion of circle implies that all essential machinery parts have been examined within a previous 5 years.

Items covered by CMS:

1. Main propulsion machinery, steam turbine.
2. Power transmission and main shafting.
3. Auxiliary engine.
4. Air compressors, air receiver and blowers.
5. CW, FO, LO, feed water, condensate, bilge, ballast and fire pumps, etc:
6. Condenser and feed water heaters, coolers, oil heaters, and evaporators.
7. Fuel tanks (more than 1 m³), cargo oil pumping installation.
8. Deck machinery.
9. Steering gear including operational test and checking of relief valve setting.
10. Reduction gears; to check the gear teeth, pinions, etc.
11. Other items of machinery and equipment, which the Society considers to be covered by CMS.

Items not covered by CSM:

1. Propeller and shaft.
2. Sea valves below load water line.
3. Boiler, EGE.
4. Cargo handling gears
5. Measurement of crank shaft deflections for ME.
6. Measurement of clearance at the aft end of stern tube.
7. Items of machinery and equipment which are not required open-up inspection at Periodical Surveys, e.g. foundation bolts, refer installation, electrical installation, incinerators, etc.
8. Performance tests, pressure tests required at Periodical Surveys.
9. Machinery and equipment of small capacity or low frequency operation, e.g. emergency air compressor, hand pump for bilge, FO tanks less than 1 m3
10. Machinery and equipment of special type or newly developed type.
11. Other items which the society considers not to be included in CMS system.

Planned Maintenance:

Planned maintenance should be flexible, and following items should be considered.
1. Weather Condition.
2. Length of voyage, trade.
3. Maintenance of Safety Equipment, and Emergency Team Training.
4. Optimum conditions for Statutory and Classification Surveys.
5. Dry Docking.
6. Manufacturer’s advises.
7. Breakdown maintenance.
8. Replacing of spares.
9. Controlling and recording of maintenance up-to-date.

Planned Maintenance should include:

1. Short term maintenance, weekly, fortnightly, and monthly.
2. Long term maintenance, 3 monthly, 6 monthly, yearly.
3. Operational maintenance, to be carried out if necessary.

Construction of a Planed Maintenance Schedule:

1. Plan must be flexible, so that changes, orders, or cargoes do not upset it unduly.
2. Adaptable to various weather conditions.
3. Length of voyage, routes and trades, that vessel is involved must be considered.
4. Maintenance of Safety Equipment and Emergency Team Training should be integrated with overall maintenance plan.
5. Appropriate equipment is brought-up to optimum condition for Statutory and Class Surveys, such as ‘Safety Equipment’, ‘Load Line’, and ‘Lifting Apparatus’.
6. Dry-docking and repair period should be integrated with the plan.
7. Manufacturer’s advises, to be complied with, and all Manufacturer’s Maintenance Logs to be completed.
8. Plan should include availability of appropriate equipment, for breakdown maintenance, due to unforeseen circumstances.
9. Provisions made for spare part replacements for wear and tear maintenance.
10. Plan must be carefully thought-out, well controlled, and efficient recording system must be kept up-to-date.

Classification Surveys:

– Annual Survey of hull and machinery.
– Special Survey of hull and machinery: the first special survey becomes due 4 years after the date of built. Special Survey can be extended up to 5 years if not completed at one time. [S/S 4+1 year.]
– Continuous Survey or running survey of hull and machinery.

Automation Survey :

Carried-out at 1 year from the date of installations and periodical Special Surveys are to be carried out at 4 years intervals. ( 1 + 4 )

At 1 year from the date of installation, during this Survey:
1. General examination of automatic and control system.
2. Examination of ship service generator in operation and control system.
3. Random checking of function indicators, alarms and control actuators.
4. Examination of machinery records to ensure that the performance of the control system are in good order through the period since last survey.
5. Machinery space fire detection and bilge alarms.

At interval of 4 years, during this Special Survey:
1. All requirements of Annual Survey are done.
2. Examination of control actuator,
3. Insulation resistance of all electrical equipment and circuits.
4. Control system of UMS for proper operation.
5. Automatic alarms and safety systems.

Tail shaft Survey:

  • Tail shaft with water lubricated bearing, to be drawn and surveyed, every 3 years for single screw, and every 4 years for twin screw.
  • Tail shaft with oil lubricated bearings, to be drawn and surveyed once every 4 years.
  • It is a survey done by Surveyor at the request of owner or his agent, due to damage of hull, machinery or equipment, which can effect the seaworthiness, or class of ship.
  • All necessary repairs to be carried out to Surveyor’s satisfaction.

Tail shaft Survey includes:

1. Complete withdrawal of tail shaft.
2. Propeller nut and tail shaft threaded end to be checked.
3. Cone, key and keyway to be checked, and forward part of the taper to be checked for crack with approved crack detecting method.
4. Tail shaft bearing wear, to be checked.
5. Stern bush and bearings, to be checked.
6. Shaft sealing arrangement, including oil system, to be checked.

Boiler Survey:

The Class Surveyor shall survey every boiler of working pressure 3.5 bar and heating surface area 4.65 m² and above.

Survey interval:
DNV & LLOYDS: Every 2-years interval until 8 years old, and every 1-year interval after 8 years old.
GL: Every 2½ years interval until 10 years old and every 1-year interval after 10 years old.

Annual Boiler Survey includes:

1. Hydraulic testing ( 1.25 x approved working pressure for not more than 10 minutes ).
2. Pressure testing of main steam piping at 15% in excess of approved working pressure for not more than 10 minutes.
3. Internal inspection, hammer test to furnace, stays bolts, fire and stay tubes, brickwork, baffles and casing.
4. Inspection of alarm and control system, fuel system, feed system, all steam piping and lagging arrangement, foundation and chocking system.
5. Checking of pressure gauge and water level gauges.
6. Testing of safety valves to blow off at the pressure not greater than 3% above w.p.
7. After 10 years old or at any time, if surveyor demands, drill test near the water line should be done to determine actual thickness of boiler shell. If found necessary, lower working pressure may be reassigned

At 4 years interval :
In addition to above Annual inspection procedure, all valves on boiler required to open-up and inspected, every 4 years at the time of Annual Survey, or at the next regular dry docking period thereafter.

Preparation for survey:

1. Clean water and fire sides.
2. Gags or clamps must be prepared for safety valves.
3. Boiler must be filled with water at a temperature not more than 38˙C for fire tube boiler and not more than 82˙C for water tube boiler.
4. Drip pan placed under all burners.
5. Tank top and bilges cleaned.
6. Pump for pressure test to be kept ready.
7. Blanks must be installed at steam valves and water level gauge.

Damage Survey:

1. It has to do with causalities and accidents, repairs, causes and remedies.
2. Damage to hull, machinery and equipment, which effects seaworthiness or classification, is to be submitted by owner and representative, for examination by Surveyor.
3. All repairs to be carried out to surveyor’s satisfaction.

When damage occurs:

If the vessel is classed, and the port has facilities of Classification Society, and Underwriter Surveyors and repairs firm:
1. Invite Classification Surveyor
2. Invite Underwriter Surveyor (appointed by Insurers)
3. Both Surveyors to survey the damage
4. Repairs to be carried out as per Class Requirements.
5. Quotation of repairer and repair cost to be submitted to Underwriter Surveyor to negotiate any reduction that may appears necessary.
6. Both Surveyors to survey the repairs when completed.
7. Repair bills must be endorsed by the Underwriter Surveyor so as to claim insurance.
8. Underwriter Surveyor does not accept bills for transportation.
9. Class Surveyor must confirm class of machinery (Interim Certificate of Class)
10. Log Abstracts and damage reports must be submitted to the Class Surveyor and owner.

If the vessel is classed, but the port is very small, and duly appointed Surveyor may not be available:
1. Call the next best surveyor.
2. If no surveyor is available, Damage Survey may be carried out by two Chief Engineers of same Flag (Port of Registry), but should not be from same company, to avoid biased report.

Actions taken by C/E when ME breakdown, fire / explosion occurred:

1. Find out extent of damage or breakdown.
2. Find out whether the damage can be repaired or not by ship crew.
3. Consider that vessel can resume the voyage or not.
4. Inform present situation to HO and take instruction.
5. Record exact times and position of ship.
6. Take pictures of damage for evidence.
7. After temporary or proper repair, resume voyage under suitable speed.
8. Prepare detail damage report and submit to head office.

CE damage report form:

1. Date, time, approximate ship position, voyage no.
2. Where damage occurs.
3. Causes and extent of damage.
4. HO confirmation and approval for major repair.
5. Actions taken.
6. Repaired condition, detail statement of clearances, measurements, etc.
7. Used and required spares to be ordered.
8. Training and instructions to prevent reoccurrence.
9. Take photos before and after repairs.

Insurance:

Ship owners insured their ships against unforeseen damage or loss such as:

  • Actual Total Loss.
  • Constructive Total Loss (the cost of repair being greater than the value).
  • Presumed Total Loss.
  • Partial Loss.
  • Third party Liabilities (collision, injury to crew)

The rate of Insurance:
It depends on size, age and engine, and a vessel with valid Certificates of Classification is likely to attract more favourable rate than a vessel without.

Insurance claim purpose:
Following items are necessary:

1. C/E damage report
2. Log abstracts.
3. Damage report form for insurance claim.
4. Class Surveyor recommendation.
5. Repair bills endorsed by Underwriter Surveyor.

Protecting and Indemnity Association:

  • This is a P&I Club or Mutual Insurance Club or Small Damage Club.
  • An association formed by Ship Owners, having certain risks to insure.
  • That certain risks are not covered by the Insurance Policy.
  • A Mutual Insurance Company, belonging to ship owners, which insures the damages relative to the ship, which are not covered by Insurance Policy.

Protecting:

1. Loss of life and personal injury.
2. Hospital, medical and funeral expanses arising from injury claim.
3. Sickness and repatriation.
4. Cargo damage due to improper navigation.
5. Oil pollution.
6. Collision damage, etc.

Indemnity:
1. Claim in respect of wrong delivery of cargo.
2. Ship’s liability to cargo, after collision, not covered by policy.
3. Fine or penalty imposed as a result of custom law, health regulations, and immigration law including smuggling.

Interim Certificate of Class:

  • Class Surveyor will issue the Certificate, when repairs have been completed to the Surveyor’s satisfaction.
  • This Certificate enables the vessel to remain in class, until the next full survey due.
  • Validity is until next survey due.

Certificate of Seaworthiness:

  • To enable to proceed to the next port, the Surveyor other than Class Surveyor issues it.
  • If the Classification Surveyor does not carry out the survey, the requisite certificate that is issued will be one of seaworthiness.
  • This Certificate enables the vessel to proceed to her next port, where a further survey by the Classification Surveyor will be conducted, so that Interim Certificate of Class can be issued.

Seaworthiness:
1. The fitness of the vessel in all respects for carrying cargo and crew in safe condition.
2. Important items concerned are stability, strength, freeboard, machinery and design, and they must be entirely satisfactory.

Franchise Clauses:

  • These state certain portion of insured value, for which Insurers are not liable to pay.
  • There are two kinds of franchises:
    [These state the percentage of the claim, which the Assured must bear.]

Deductible:

1. If amount of loss does not exceed the franchise amount the Insurers (Underwriters) are not liable to pay at all.
2. But if the amount of loss exceeds the franchise amount Insurers are liable to pay that portion which exceeds the franchise amount.
[Only claims in excess of certain percentages are paid, i.e. the Assured pays the first so much
percentage of any claim.]

Non-Deductible:

1. If amount of loss does not exceed the franchise amount the Insurers (Underwriters) are not liable to pay at all.
2. But if the amount of loss exceeds the franchise amount Insurers are liable to pay the whole amount.
[The Underwriter pays the whole claim if it exceeds the stipulated percentage.]

 

Load Line Survey:
1. Carried out as first Survey when a new ship is completed.
2. During this survey freeboard arrangement and conditions of assignment, are made in accordance with International Regulations and Documentation.
3. After thorough inspection, Load Line Certificate is issued, and its validity is 5 years, subjected to Annual Survey.
4. Load Line Renewal Survey held at 5 years interval from the date of build, and whenever a periodical Special Survey is made.
5. Validity of Load Line Certificate extends to the end of next Special Survey.
6. During this survey, all freeboard items to be examined, and load line markings to be verified. [With trammel gauge]
7. On satisfactory completion of the Survey, an International Load Line Certificate, valid for 5 years is issued.
8. Load Line Annual Inspection carried out within 3 months ± anniversary date of the Certificate.
9. Main purpose of Load Line Survey is, to examine that the ship construction complies with Requirements of Convention.
Requirements can be grouped into 4 categories:
1. Structural Strength.
2. Watertight Integrity.
3. Stability.
4. Crew Quarter Protection.

Conditions of Freeboard Assignment: Why it is important?

1. Efficient means of protection must be provided for all openings to hull and superstructure, for protection of crew in heavy weather, and for rapid freeing of water from weather deck.
2. Condition of Assignment must be maintained, at all times in satisfactory condition.
3. Annual Inspection to be made by assigning authorities, to ensure that they have been maintained in satisfactory condition for continued validity of Load Line Certificate.

Preparation for Load Line / Annual Survey:

Ship Officers/Engineers should ensure, the following items are in efficient condition, prior to the Classification Society Surveyor’s arrival on board.

1. Load line marks, verified with existing Load line Certificate.
2. Coamings and closing appliances of exposed hatchways, hatchways within superstructures, to be examined.
3. Holding-down clips/bolts are in good order; packing and seats are watertight.
4. Watertight steel hatch covers are to be hose-tested (pressure not less than 2 kg/cm² from a distance of 1.5m with ½ ” bore jet) for water-tightness.
5. Spring-loaded battening-down wedges between covers, and holding down cleats, to be in good working condition.
6. Exposed engine casing and their openings, fiddley openings, ER skylights and their closing appliances, to be checked and tested. ER skylight to be able to close from remote position.
7. Test Ventilators, check all flap levers are free, and locking pins are in place and secured by chain to ventilation casing.
8. Check air pipes and their closing means, flame traps for fuel oil tank’s air pipes, are in order.
9. Watertight doors and closing arrangements to be checked.
10. Scuppers and their discharge pipe and valves below the freeboard deck, checked for corrosion/wastage.
11. Gangways and cargo ports below freeboard or superstructure deck, to be checked.
12. General condition of hull, as far as could be seen.

Load Line Certificate:

  • A Certificate issued to a ship, if she is built and maintained thereafter, according to the requirements of International Convention on Load Line (1966)
  • Issued by the Administration or Classification Society.
  • Validity is 5-years and subjected to Annual Survey.

FO DB Tank Survey:

Transferring, cleaning and gas freeing must be done.

Testing of atmosphere:

˗ Toxicity
˗ O₂ content with Oxygen Analyser
˗ Explosive Gases with Explosimeter
˗ Gas free certificate from Chemist.

Survey:

1. Heating coil leak test: [1.5 times working pressure.]
2. Condition and testing of level alarm
3. Condition of sounding pipe, striker plate and flame trap
4. High temp. alarm sensor
5. Internal inspection by surveyor.

Sounding pipe requirements:

1. Used to determine the dept of liquid in a tank.
2. Should be as straight as possible.
3. If it is not possible, pipe curvature should allow easy passage of sounding rod or chain.
4. Normally, bore of pipe must be not less than 32mm.
5. Striking pad of adequate size and thickness placed under the pipe.

IOPP Certificate:

Issued after Survey is carried out by Administration, in accordance with International Convention for Oil Pollution Prevention. Validity is 5 years.

Checking procedure for IOPP Certificate, When CE sign-on:

1. Check the validity of certificate.
2. Check the ORB up to date recording.
3. Visual inspection of plants in good order.
4. Check 15-ppm alarm and automatic stopping device.
5. Check spare filter element, at least one no.
6. Waste oil tank and capacity.
7. Compare fuel consumption and sludge formation.
8. Incinerator capacity and workability.

IOPP Survey preparations:

1. Validity of the IOPP Certificate checked.
2. Proper entry of ORB and, sludge disposal receipts to shore facilities attached to ORB.
3. Calculate the sludge formation, and compared with 1% of voyage fuel consumption.
4. Incinerating time, incinerated waste oil amount, remainder of waste oil in waste oil tank should be reasonable.
5. Incinerator kept ready for demonstration, such as heating of waste oil tank, alarms, control and functional test, done prior to survey.
6. OWS in good order, its piping free from oil leaks, overboard valve from OWS locked in closed position. If possible, one section of discharge pipe removed and free from oil residues.
7. ODM checked for 15-ppm alarm and automatic stopping.
8. High level alarms of sludge tank, waste oil tank and bilge holding tank checked.
9. Spare filter for OWS must be onboard.
10. USCG Notice posted near OWS and bilge pumping out station

Survey by CE:

Requirements:

  • CE must have first class competency certificate or equivalent.
  • At least 3 years service as CE on owner’s vessels.
  • Should be at sea or in port with no Class Surveyor.
  • Generally cannot survey on Safety Equipment, pressure vessels, and main engine except in unit overhaul.
  • Can survey auxiliary machinery such as, AE, pumps, and Air Compressors.
  • DNV allows half of all items covered by CMS, of which there are more than one, may be surveyed by CE.

Confirmatory Survey:

1. When any machinery and equipment, allowed to be surveyed by CE, were opened-up and examined by CE at sea, Confirmatory Survey of these items must be done by the Class Surveyor at next port of call, or the first port of opportunity.
2. During this survey, show the followings to Class Surveyor:
a) Relevant entries in log book.
b) Two copies of statement, signed by CE.
c) Description of items surveyed by CE.
d) Spare parts replaced.
e) All photos for evidence.
3. If the surveyor does not satisfied, he has right to open up the item for inspection. If he satisfy, he will issue Interim Certificate of Class.

AE survey by CE:

Safe operation of propulsion must not be effected, when CE surveys AE.
1. All cylinder covers, valve gears, pistons, piston rings, liners, top and bottom end bearings, all upper half of main bearings, gudgeon pins are to be opened up.
2. To withdraw at least two bottom half bearings for inspection.
3. Checking of all crank pin bearings, journals and gudgeon pins.
4. Cylinder liner gauging and recording.
5. L.O. cooler to be opened up for inspection.
6. Defective attached pumps such as LO pump, FW pump, etc. to be opened up.
7. Testing of all safety devices, alarm and trip.
8. Crankshaft deflection taken and recorded after reassembled.

Confirmatory survey by Class Surveyor:
» He has rights to open up at least two main bearings and two bottom end bearings, and crankshaft deflections to be taken and checked with CE records.
» Run the engine and load-tested. All safety devices tested for alarms and trip for generator and switchboard, and are to be witnessed by the surveyor. (DNV).

Generator load test:

1. After priming the AE, start and run under no load, low speed condition for about 3 to 5 min.
2. Then stop and checked externally for overheating. If no overheating, crankcase doors to be opened and checked temperature of bearings and running gears.
3. If satisfactory, restart the engine at full speed, no load condition for about 30 min., then stopped and recheck again.
4. If satisfactory, restart and load-shared with running generator engine. Load sharing should be gradually increased in small steps, taking about 6 to 10 hours to reach at full load condition. While running in full load, another generator to be run in stand-by for possible emergency use. Synchronising or load sharing steps: 25%, 50%, 75%, and 100% within 6 to 10 hrs.
5. All necessary items checked, during load increasing steps.
6. Then peak pressure indicator and other performance data, taken for each cylinder and compare with test results.
7. Load test should be done, until preferential trip initiates.

A/E Damage Insurance Claim:

Items necessary to submit to Superintendent Engineer are:
» CE damage report.
» Log abstracts.
» Damage report form for insurance claim.
» Class surveyor recommendation.
» Repair bills endorsed by Underwriter Surveyor.

If A/E damage occurred at sea:

1. Date, time, position, voyage no., where the damage occurred, extent of damage, causes of damage, are reported to Head Office in detail.
2. Take HO confirmation and approval for major repair.
3. Take required damage photos.
4. When at nearest port, repair condition, photos before and after repair are submitted to Surveyor for Confirmatory Survey.
5. If Surveyor does not satisfy, he has right to open-up for inspection.
6. If Surveyor is satisfied, he will issue Interim Certificate of Class, and give recommendation.

If A/E damage occurred in Port:

1. Invite Class and Underwriter Surveyors through Master or Agent to make surveys.
2. Negotiate with shipyard repair firm, about cost and prices.
3. After completion of shipyard repair firm’s work, Surveyor will inspect the AE, and issue Interim Certificate of Class, and Underwriter Surveyor will inspect and give repair cost and certified endorsement.
4. Repaired condition with photos, and used spares, reported to HO and required spares ordered.

Surveys, requested by owners, charterers, underwriters and authorities:
1. Damage Survey
2. On and Off Hire Survey
3. Lay-up Survey
4. IMCO Survey (Inter-governmental Maritime Consultative Organisation.)
5. Pre-loading Survey
6. Draught Survey
7. Ullage Survey
8. Conditional Survey: [the ships over 15 years of age may be subjected to survey, annually, so as to ensure their seaworthiness, only upon request by owners and underwriters.]

On and Off Hire Survey:
1. The most time-consuming survey and must be done in daylight, with the hatches fully open, empty and clean.
2. Two Surveyors will have to carry out this Survey.
3. One representing the owner, may be the Master, and the other representing the Charterers.

The areas of Survey include:
1. Portside Bulwark/rails and Deck. [Bulwark is the part of ship’s side, above Upper Deck.]
2. Starboard side Bulwark/rails and Deck.
3. Deck houses and cargo gears.
4. Hatch coamings and hatches.
5. Shipsides, Tank tops, Bulkheads fore and aft.
6. Bunker Survey.

In Water Survey:

1. Due to increasing in size of oil tankers and bulk carriers and consequently, small numbers and size of docks incapable of docking these vessels, In Water Survey is permitted by Class.
2. This survey includes visual examination of hull, rudder, propeller, sea inlets and measuring the wearing of rudder bearings and cleaning of hull by suitable methods.

Limitation:
1. Not periodical special survey.
2. For less than 10 years old of vessels.
3. Must have Class notation to suit for in water survey.
4. Hull painted with high resistance paint and fitted with impressed current system for hull protection.
5. Class must approve Diver Firms.
6. Ship draught not more than 10 meters.

Requirements:
1. Hand held closed circuit TV camera that can be controlled remotely from surface monitoring system.
2. Communication between Diver Party and Surveyor.
3. Water is clean and clear.
4. Carried out in daylight.

Docking Survey:

1. The ship must be examined in dry dock preferably at 1-year intervals, but new Class Regulations allowed intervals of up to 2 years.
2. The vessel is to be placed in dry dock or upon a slip way and the keel, stern frame post, rudder and outside plating, propeller, exposed part of stern bearing assembly, rudder pintle and gudgeon securing arrangements, sea chest, strainers and other fastenings are to be cleaned and examined.
3. The stern bearing clearance and rudder bearing clearance are to be ascertained.

Underwater [Bottom] Survey on Dry Dock:

1. Shell plating washed and brushed down, checked for distortion, bulging, roughness and corrosion.
2. Welding seams inspected for cracks.
3. Zinc anodes checked for replacement.
4. Shipside valves and cocks removed, overhauled and refitted.
5. Shell box or Sea Chest wire brushed and applied anti-fouling paint.
6. Remove drain plug of rudder to determine the present of water.
7. Measure wear down of rudder and jumping clearance.
8. Bearing metal of gudgeon pin of rudder checked and clearance
must not exceed 6 mm.
9. Pintle nuts with locking device checked.
10. Propeller carefully examined especially near the tip on the driving face and fore side for cavitation. Damaged propeller blades repaired.
11. Wear down of tail shaft measured. For oil lubricated: 2 x original clearance.
For water lubricated: maximum 10 mm.
12. Stern tube checked for tightness.
13. For CPP, checked for good working order.
14. Anchor and chain cable, lay up and measured.

Dry Docking:

Required Plans and Arrangements for Docking:
1. Docking plan.
2. General arrangement plan.
3. Capacity plan.
4. Shell expansion plan.
5. Shell painting area plan.
6. Mid ship section plan.
7. Longitudinal section plan.
8. Anode plan.
9. Shafting and propeller arrangement.
10. Rudder, to check.

Docking plan:

▭ Provides the positions of frame spacing, watertight bulkheads, docking plugs, etc.
▭ Determine the positioning of keel blocks, bilge blocks, bilge shore, breast shore
when the ship is on dock.

Preparation for Dry Docking: [As a CE.]

1. Take all information from HO and dockyard.
2. Sent Docking Plan to Dockyard.
3. Prepare dockyard and ship staff repair lists and survey items.
4. Prepare necessary spares and store, drawings, Manuals, Certificates, special tools and measuring equipment.
5. 2/E should be instructed to perform the followings:

a) Label all sea valves, all shipside valves and cocks. Mark the positions of items to be repaired, with tags or colour code.
b) Keep Emergency Fire Pump, Emergency Generator, Air Compressors, Emergency Air Bottle, and portable Fire Extinguishers in good order.
c) Lock Fixed Fire Fighting Installation, as per shipyard rules.
d) Shut down Boiler, OWS, Sewage Plant if dockyard does not allow.
e) Lock overboard discharge valve in closed position.
f) Fill up Settling and Service Tanks.
g) Press up Air Bottles and Emergency Air Bottle, and shut the valves tightly.
h) ME crankshaft deflections to be taken and recorded.
i) Hose down tank tops, and empty Bilge Holding Tank, Sludge Tank, Waste Oil Tank.
j) Prepare for receiving of Shore Power Supply, International Shore Connection, cooling arrangement for Air Conditioning and Provision Plants.
k) Provide fire watch in ER at all times, and follow Dockyard Fire and Safety Regulations.
l) Adjust required trim and draught, with deck officer.
m) Take soundings of DB tanks and cofferdam.

During Docking:
1. Discuss with the superintendent and dockyard repair manager about repair jobs.
2. Assist Surveyor and record the survey items.
3. Witness all alignment works and clearance measurements.
4. Take and record propeller shaft wear down, rudder wear down and jumping clearance.
5. Check oil tightness of stern tube.
6. Check all completed underwater jobs, done by dockyard.
7. Check all sea valves, shipside valves and cocks, after overhauling.
8. Check all repaired jobs done by ship staff, and used spares and store.
9. Make daily records.

Undocking:
1. Check all repair and underwater jobs in accordance with repair list.
2. Check all measurement data are correct and completed.
3. Make price negotiation.
4. When sea water level covers the sea chest, each sea valve should be opened and checked for any leakage.
5. Purge air from cooling seawater pumps, run the pumps and check pressure.
6. Test run the ship generators, until satisfactory, and cut out shore supply, cut in ship generator, disconnect the shore connection, restart seawater pump, record the time and read watt meter.
7. All sea valves, shipside valves, repaired pipes, repaired jobs must be finally checked, before leaving the dock.
8. Prepared for ME.
9. All DB tank soundings checked.

After Leaving the Dock.
1. Checked ME crankshaft deflection and compare with former record.
2. Prepare for Docking Report.

Cargo ship Safety Construction Certificate:

  • Issued after survey to every cargo ship of 500 GRT and over, by the government of Flag State.
  • Validity is 5 years, subjected to survey at specified intervals.
  • During survey, following items must be in accordance with the requirements of SOLAS 1974 Convention.

1. Ship structure, including structural fire protection.
2. External examination of ship’s bottom.
3. Electrical installation.
4. Steering gear.
5. Pressure vessels and fitting.
6. Main and auxiliary machinery.

Cargo ship Safety Equipment Certificate:

  • Issued after survey to every cargo ship of 500 GRT and above, by the government of flag state.
  • Validity is 2 years and annual inspection of ± 3 months.
  • Safety Equipment Survey, consists of inspection and demonstration:

1. Fire fighting appliance, FFA
2. Life saving appliance, LSA
3. Navigation equipment
4. Vessel documentation
5. Alarm system.

Concerning items for CE:

1. All portable and semi-portable fire extinguishers
2. Fixed installation of fire fighting
3. Fixed fire detection and alarm system
4. Fire man’s outfit
5. Emergency fire pump, main fire pump
6. Emergency stop switches, remote quick closing valves, skylight, watertight doors
7. Emergency generator and lighting system
8. Escape ways in ER.
9. Steering gear and communication system
10. Life boat engines and launching system.
11. All the items required by SOLAS must be prepared.

Some government administrators publish checklist for survey. This is an essential tool for preparing for a survey, so that one surveyor should be able to complete the survey in ½ day.

Safety Equipment Survey:

  • Government body carried out at every 2-year interval, and annual inspection of its validity.
  • At every port, where the ship called on, Government body concerned has a right to inspect Safety Equipment, IOPP Certificate, Sewage treatment plant, Marpol equipment, and ORB for Port State Control measures.

1. To inspect Fire hoses, Nozzles and container box.
2. Fireman’s outfits: Breathing apparatus.
3. All portable extinguishers.
4. Emergency and Main fire pumps.
5. Emergency generator.
6. Fixed installation [gas level, cleared lines and nozzles, operating mechanism and alarm system].
7. Audible Fire alarms, Fire detection system, Abandon ship warning, and Ship Siren and Muster list.
8. Stop switches outside ER, for fans, fuel pumps, fuel tank valves, Skylight doors, Watertight doors, Fire dampers.
9. Inert gas system of cargo ships, 500 tons Gross Tonnage and above.
10. Life raft Certificate.
11. Life buoys, Smoke floats, Buoyancy lines.
12. Lifeboat internally and externally.
13. Condition of Buoyancy tanks inside lifeboat.
14. Illuminating power sources, for launching of Lifeboat and Rafts
15. Latest Nautical Publications.
16. To run Lifeboat Engine, ahead and astern in water.
17. To swing out all lifeboats at least 50% lowered into the water.
18. To lower Davit span ropes and Boarding ladders.
19. To lay out and survey all lifeboat equipment.
20. To survey Life jackets.
21. To check Navigation lighting.
22. To check pilot ladder with lighting.
23. To inspect fall release mechanism [free fall or float free].

Certificates onboard:

1. Certificate of Registry
2. International Tonnage Certificate
3. International Load Line Certificate
4. International Load Line Exemption Certificate
5. Certificates for Master, Officers and Ratings
6. Derating or Derating Exemption Certificate
7. International Oil Pollution Prevention Certificate
8. International Sewage Pollution Prevention Certificate
9. International Safety Management Certificate, SMC
10. International Medical Certificate
11. Passenger Ship Safety Certificate
12. Cargo Ship Safety Construction Certificate, SAFCON
13. Cargo Ship Safety Equipment Certificate, SEC
14. Cargo Ship Safety Radio Certificate
15. Exemption Certificates for SAFCON, SEC and Radio Certificate
16. Certificate of Classification
17. Certificate of Insurance or other financial security
in respect of civil liability for oil pollution damage.

18. International Pollution Prevention Certificate
for the Carriage of Noxious Liquid Substances in Bulk. [NLS Certificate]
19. Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk
(Chemical Tanker)
20. Certificate of Fitness for the Carriage of Liquefied Gases in Bulk
(Gas Carrier)

SOLAS Certificates:

  1. Passenger Ship Safety Certificate
  2. Cargo Ship Safety Construction Certificate
  3. Cargo Ship Safety Equipment Certificate
  4. Cargo Ship Safety Radio Certificate
  5. Cargo Ship Safety Certificate 1
  6. Exemption Certificate
  7. Document of Compliance with the special Requirements for Ships carrying Dangerous Goods
  8. Minimum Safe Manning Document
  9. Document of Authorization for the Carriage of Grain
  10. International Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk
  11. International Certificate of Fitness for the Carriage of Liquefied Gases in Bulk
  12. International Certificate of Fitness for the Carriage of INF Cargo
  13. Safety Management Certificate (ISM)
  14. Document of Compliance (ISM)
  15. High Speed Craft Safety Certificate
  16. International Ship Security Certificate

MARPOL Certificates:

MARPOL Annex I:
1. International Oil Pollution Prevention Certificate (IOPP Certificate)
2. Statement of Compliance with CAS (as a supplement to ship’s IOPP Certificate)

MARPOL Annex II:
1. International Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk
2. Certificate of Fitness for the Carriage of Dangerous Chemicals in Bulk
3. International Pollution Prevention Certificate for the Carriage of Noxious Liquid Substances in Bulk (NLS Certificate)
4. Certificate of Fitness for Offshore Support Vessels

MARPOL Annex IV:
1. International Sewage Pollution Prevention Certificate
2. Result of calculation of moderate rate of discharge in accordance with MEPC.157(55)

MARPOL Annex V:
1. Garbage Management Plan
2. Garbage Record Book

MARPOL Annex VI:
1. International Air Pollution Prevention Certificate
2. Engine International Air Pollution Prevention Certificate
incl. Technical File and Record Book of Engine Parameters if applicable.
3. International Energy Efficiency Certificate

Oil Record Book: Part I

  • Operations involving oil and oily mixtures recorded in ORB.
  • Dates, geographical position, quantity, tank identification, and duration of operation entered.
  • Port State Authority may take copies of entries, and if so requested, the master is required to state that it is a true copy.
  • ORB retained onboard for 3 years after date of last entry.

To be recorded:

1. Ballasting and cleaning of fuel oil tanks. (Code a.)
2. Discharge of dirty ballast or cleaning water from oil fuel tanks. ( b.)
3. Disposal of oil residues (sludge). ( c.)
4. Non-automatic discharge overboard or disposal otherwise, of bilge water accumulated in machinery spaces ( d.)
5. Automatic discharge overboard or disposal otherwise, of bilge water accumulated in machinery spaces ( e.) (e.g. transfer of bilge water to slop tank) (identify tank)
6. Conditions of ODM and Control System. ( f.)
7. Accidental or other exceptional discharge of oil. ( g.)
8. Bunkering of fuel or bulk of LO. (h.)
9. Additional operational procedures and general remarks. ( i.)

Oil Record Book: Part II

To be recorded:

1. Loading and unloading of oil cargo.
2. Internal transfer of oil cargo during voyage.
3. Cleaning of cargo tanks.
4. Crude Oil Washing (COW System only)
5. Ballasting of cargo tanks.
6. Ballasting of Segregated Clean Ballast Tanks (CBT Tankers only)
7. Discharge of dirty ballast.
8. Discharge of clean ballast contained in cargo tanks.
9. Discharge of ballast from Segregated CBTs. (CBT Tankers only)
10. Discharge of water from Slop Tanks into the sea.
11. Condition of ODM and Control System.
12. Accidental or other exceptional discharge of oil.
13. Additional operational procedures and general remarks.
14. Loading of ballast water. (Tankers engaged in specific trades)
15. Re-allocation of ballast water within the ship. (do)
16. Ballast water discharged to reception facilities. (do)

Shipboard Oil Pollution Emergency Plan: SOPEP.

Every oil tanker of 150GRT and above, and every ship of 400GRT and above, shall carry onboard a Shipboard Oil Pollution Emergency Plan.

The plan shall consist at least of:

1. Procedures to be followed by Master, or other person having charged of the ship, to report an oil pollution incident.
2. List of authorities or persons to be contacted, in the event of oil pollution incident.
3. Detailed description of actions to be taken immediately by persons onboard, to reduce or control the discharge of oil.
4. Procedures and point of contact onboard, for co-ordinating shipboard action with local authorities in combating the pollution.

Procedures, when accidental oil overflow occurs:

1. Notify Harbour/Terminal Authority immediately through the Master.
2. Actions immediately taken by persons onboard to stop, reduce or control the oil discharge.
3. Co-ordinate shipboard actions with local Authorities.
4. Inform owner, agent, P&I Club, Flag State Authorities, and vessels in vicinity.
5. Invite P&I (Protection and indemnity) correspondents.
6. Record in ORB, time & place of occurrence, approximate amount & type of oil, circumstances of discharge or escape.

Sludge Tank requirements:

1. Capacity must be minimum 1% of used HFO for 30 days (or)
½ % of used DO for 30 days.
2. Sufficient manholes to reach all parts of tank.
3. Adequate heating arrangement.
4. No direct connection between sludge tank discharge piping and overboard discharge piping.
5. Fitted with designated pump, having suitable capacity and discharge head.
6. Fitted with standard discharge connection.
7. Fitted with high level alarm.

Sludge Tank Capacity and Requirements:

For ship, which does not carry ballast water in oil fuel tank, minimum sludge tank capacity should be calculated as:

V = KCD m³

Where K = 0.01 for ship, where HO is purified for ME ( i.e. 1% )
K = 0.005 for ships using DO or HO, which does not require
purification before use ( i.e. ½ % )
C = Daily fuel oil consumption.
D = Maximum period of voyage between ports ( in days).
In absence of precise data, a figure of 30 days should be used.
Note: Sludge Tank Capacity (min) = 0.01 or 1% of used HFO for 30 days. [or]
0.005 or ½ % of used DO for 30 days.
Requirements:
1. Manhole
2. Heating coil
3. No direct connection to overboard.
4. Sludge pump.
5. International Discharge Connection.
6. High level alarm.
Biological Sewage Treatment Plant:

1. The unit is divided into 3 compartments: Aeration Chamber, Settling Chamber and Chlorinator.
2. Sewage enters Aeration Tank through soil inlet, and retained for about 24 hours and thoroughly mixed and aerated by aerators located at the bottom of the tank.
3. Aerobic bacteria and micro-organisms breakdown the organic waste and produce new bacteria cell.
4. Air, which provides oxygen for bacteria and micro-organisms, is supplied by Rotary Blowers to aerators.
5. The mixture is replaced by incoming sewage into Settling Tank, after passing through coarse screen.
6. All solids are precipitated in Settling Tank as Activated Sludge, which are then returned to Aeration Tank by airlift, and mixed with incoming raw sewage.
7. Clean liquid is displaced into Chlorinator, where remaining bacteria are killed.
8. Discharge of harmless effluent from Collecting Tank is controlled by Float Switch connected to Discharge Pump.

Important Equipment:

1. Two Rotary Blowers
2. Two Discharge Pumps.
3. Safety Valve at Aeration Blower.
4. High water level activating switch.
5. Low water level activating switch.
6. High water level alarm.

Biochemical Oxygen Demand, BOD:

  • Amount of Oxygen taken up by Bacteria Incubation Process, in PPM.

Coliform Count:

1. Coliform is the name given to bacteria group, found in intestine.
2. Not normally harmful, but can cause Dysentery, Typhoid, and Gastro-enteritis.
3. Coliform Count checks effectiveness of disinfection.
4. Carried-out on effluent sample and incubating it for 24 – 48 hours at 35°C.
5. Coliform Bacteria count: 200/100 mlt. [Maximum].

Welding:

Welding on Cast Iron:

Oxy-acetylene Welding:

1. Flame adjusted with slightly excess acetylene, to get a temperature of
1200°C, [Melting point of CI].
2. Welding rod: pure CI with high silicon content.
3. Part to be welded is preheated to 600 ~ 700°C, to avoid excessive stresses.
4. During welding, gas bubbles are developed in molten weld pool. By striking the pool in circular motion with welding rod, these bubbles can be removed.
5. It is necessary to use welding flux.

Arc Welding:

1. Electrode: pure nickel (or) nickel iron.
2. Weld metal, deposited in short thin beads with small electrode and low amperage, to avoid local heat built up and expansion, around weld point.
3. Casting is allowed to cool, between each run.

Welding on Aluminium:

Gas Welding:

1. Used for thickness of plate up to 3/16″.
2. Slightly excess acetylene is used, due to lower melting point, 660°C.
3. Welding rod: Pure aluminium.
4. Necessary to use flux, to dissolve oxide.
5. Avoid inhalation of smoke, produced during welding.

Arc Welding:

1. Thickness of plate ¼ ” or more.
2. Electrode: 95% Aluminium, 5% Silicon: with 20°of vertical.
3. Keep arc as short as possible, low amperage and movement is in straight line.
4. Welding speed is 3 times faster than mild steel.
5. Thick plate should be preheated for smooth weld.
6. Traces of flux, removed with hot water after gas or arc welding, otherwise flux corrosion will occur.

Inert gas welding:

1. Welds are superior in strength and pressure tightness.
2. No flux is required, so no risk of corrosion.
3. Very high speed is possible with welding machine.
4. Gas metallic arc welding GMAW or MIG is easier to use, particularly where position welding is needed, vertical, horizontal or overhead.
5. For plate thickness of ¼ ” MIG is more economical and practical.

CE’s Instruction, regarding Welding Equipment handling:

1. Leather gloves, Safety shoes, helmet, and clean clothing [not oily Boiler Suit] to be worn.
2. Remove combustible material from vicinity.
3. Wear Safety Goggle when chipping and grinding.
4. One bucket of water and portable fire extinguisher kept near-by.
5. Cable connections, tight and well insulated.
6. To avoid Welding in confined spaces.
7. Never use oxygen and acetylene without attached pressure regulator.
8. Open oxygen cylinder valve slowly, and acetylene cylinder valve not more than 1½ turns.
9. Never attempt to mix any other with oxygen cylinder, and transfer or mix acetylene from one bottle to another.
10. Never use acetylene at a pressure higher than 15 psi [1kg/cm²].

Welding Distortion:
Depends upon:

1. Cooling rate.
2. Size of work.
3. Heat conductivity.
4. Melting point.
5. Welding speed.
6. Type of electrode.

Oxy-Acetylene Welding

  • Never use Oxygen and Acetylene without pressure reducing regulators attached to cylinders.
  • Open Oxygen cylinder valve slowly and fully.
  • Open Acetylene cylinder valve not more than 1 turns.
  • Use Acetylene at a pressure not higher than 15 psi (1 kg/cm²).
  • Pressure ranges of 20 – 39 psi for Oxygen and 1 – 12 psi for Acetylene should be used depending on tip size, torch type and thickness of work.

Electric Arc Welding

  •  Electrode diameter 1/16″ Ampere controlled bet: 50 – 100 Amp.
    Voltage 30 Volts
    Thickness of plate up to 3/16″
  • Electrode diameter 1/8″ Ampere controlled bet: 125 – 175 Amp.
    Voltage 28 Volts
    Thickness of plate above 1/2″

Electron Beam Welding:

1. A welding process directing high energy electron beam on workpiece (anode),
in a high vacuum chamber.
2. Applied to rare metal, and no electrode, no welding rod and no gases required.
3. This process can weld deeply in one pass, without overlapping.
4. Potential difference between cathode and anode is 15 kV.
Speed of electron flow, 140,000 miles/sec.

Testing of material:

1. Non- Destructive Test
2. Destructive Test.
Non- Destructive Tests:

Carried-out on components and not on test pieces:

1. Visual Probe
2. Electrical eddy current
3. Liquid penetrant
4. Magnetic particles
5. Ultra-sonic
6. Radiographic inspection

Destructive Tests:

Carried-out only on specimen, which are subjected to damage during testing.

1. Harness test
2. Impact test
3. Tensile test
4. Bend test
5. Creep test
6. Proof test

Arctic D steel:

» If part of ship’s structure is liable to particularly low temperature, a special type of steel known as Arctic D is used, as normal grade of steel is not suitable.
» Has higher tensile strength than normal mild steel.
» Has higher impact strength.
» Most important quality is its ability to absorb Impact value of 40 Joules at – 55°C,
in Charpy Impact test using standard specimen.

ISM Code:

IMO has adopted International Safety Management Code on 4th Nov 1993 for safe operation of ships and pollution prevention, in accordance with SOLAS, MARPOL and STCW.

Objectives:

1. To cover safety and pollution
2. To provide a framework for achievement of Total Quality System ISO 9002,
and ISM Code.

Purpose:
Safe management and operation of ship, and Prevention of marine pollution:

Mainly to ensure:
1. Safety at sea
2. Prevention of human injury or loss of life
3. Avoidance of damage to marine environment and property
Implementation:
Every shipping company should develop, implement and maintain Safety Management System SMS.

SMS includes following requirements:

1. Safety and Environmental Protection policy.
2. Instruction and procedure for safe operation of ship, and protection of environment, in compliance with International and Flag State Legislation.
3. Lines of communication between Shore-based and Shipboard personnel.
4. Procedures for reporting Accidents and Non-Conformities.
5. Procedures for preparedness and response, to emergency situations.
6. Procedures for Internal Audits and management reviews.

Documentation:

Quality/safety system should include following levels:
1. Quality/Safety Policy Manuals.
2. Quality/Safety Procedures Manuals.
3. Instruction Manuals.

Mandatory key dates:
1/7/98 applied to all passenger ships, bulk carriers, oil tankers, chemical and gas carriers. 1/7/2002 applied to all other cargo ships.

Certification:
Flag State Administration or Government or authorised body, issue Certificates
valid for 5-years, after thorough Audit.

Safety Management Certificate SMC:

  • Issued to the ships, audited 2 ½ years after an Initial Audit, [within ± 6 months] and subjected to a Renewal Audit, before 5-years period has elapsed, but not later than 3 months before expiry date.
  • It verifies that the company and its shipboard management operate in accordance with approved Safety Management System, SMS.

Interim SMC:
For ships that are taken-up into shipping company anew, and it is valid for 6 months.

Document of Compliance DOC:

» Issued to onshore organisation, which is audited annually after an Initial Audit, and subjected to a Renewal Audit, before 5-years period has elapsed, but not later than 3 months before expiry date.

Interim DOC:
For a new company, valid for 12 months, or for an existing company if new ship-type enters the company’s fleet, valid for 6 months.

General Checklist for Audit:

1. Certificates and documents including ORB, Logbooks.
2. Safety in general.
3. Testing and drills.
4. Navigation equipment.
5. LSA.
6. FFA.
7. Radio installation including GMDSS.
8. Load Line.
9. Machinery in ER.
10. Electrical equipment.
11. Mooring equipment.
12. Cargo gears.
13. Hull construction.
14. Marine pollution.
15. Accommodation.

Main Drills in ISM:

1. Lifeboat Drill
2. Fire Drill
3. Abandon Ship Drill
4. Man Overboard Dill
5. Enclosed Space Rescue Drill
6. Oil Spill Response Drill
7. Emergency Steering Gear Drill

SMC:
Issued by;
 Administration
 Organization recognized by Administration.

DOC:
Issued by;
 Administration
 Organization recognized by Administration
 Another contracting government recognized by Administration.

CE hand over / take over:

1. Discuss with outgoing CE about machinery condition and standing order from HO.
2. To read, hand over note / maintenance record.
3. Check logbook at least for last 3-months, CMS quarterly list, Survey items, previous voyage report ORB up-to-date filling, garbage book, sludge formation compared with 1% of voyage fuel consumption, sludge remaining onboard, all certificates, documents, and validity such as IOPP, ISPP etc:
4. Take all FO, LO tank soundings, calculate ROB, based on API gravity method, and check with log entry. Ensure fuel consumption is enough for next port or next bunker port.
5. Check all running machinery, MARPOL equipment, OWS, incinerator, sewage plant, FFA, emergency generator, quick closing arrangement and lifeboat engine.
6. Check standard spares and store, special tools and measuring equipment.
7. If everything is OK, sign the hand over note.

CE’s Routine Works:

i. Every morning: Round check of operating machinery and engine room,
Discuss with 2/E, about ER repair and maintenance jobs.
Discuss with master, about ship situation and company instruction.
ii. At noon: To check ER logbook, FO, LO, DO consumption and ROB,
Performance and running hours of machinery.
Prepare Noon Report.
iii. Once a month: Fuel and LO onboard.
Store and spare inventory.
Maintenance report and breakdown report.

iv. Every voyage: Voyage Report.

CE reports: includes confidential report, voyage report, LO and FO consumption report, maintenance report, repair list, store and spare report and vouchers.

Joining a vessel, which is not commissioned. (New ship delivery)

1. Check Specifications and Class Requirements thoroughly.
2. Inspect the works of shipyard staff for final acceptance. Unsatisfactory works should be informed to company representatives and dockyard manager.
3. All alignment and clearance measurement works, witnessed by CE.
4. Before closing the tank manholes, make final inspection.
5. Before undocking, all underwater jobs must be completed and checked by CE.
6. Check the list of spares to be supplied, and inform if necessary items are missing.
7. Received spares properly stored and recorded.
8. Make familiar with all the layout of machinery, piping, cooling arrangement, etc.
9. Check fire fighting system, and location of remote stops and shut-off devices.
10. When other engineers arrived, CE must explain the layout and operations of machinery.
11. All initial records, ideal conditions, shop test records, trial test records must be kept for the whole life of ship.

COC ORAL EXAM PREPARATION (PART- 3) – ELECTRICAL

Electrical Survey:

Electrical equipment inspected and tested, during complete engine survey, at 4 years interval.
Such a survey is prescribed, under the rules and regulations for the classification of ship.
Following survey items generally apply to all ships:
1. Generators and governors.
2. Circuit breakers
3. Switchboard and fittings (main and emergency switchboard, distributor switchboard).
4. Cables
5. Insulation resistance
6. Motors and Starters
7. Emergency power equipment
8. Parts of steering gear
9. Navigation light indicator

For UMS operation:
1. Alarms associated with ME, AE, lubricating and cooling, tested for correct operation.
2. Electrical circuits from various sensors such as pressurestat, flow switch, level switch, temperature switch, tested.
3. Action of auto-shut down for ME and AE, auto-starting up of stand-by units, tested.
4. Auto-starting of emergency generator, demonstrated.
5. UMS requirements demand that a stand-by main generator should be automatically started on loss of duty generator within 45 sec.
6. Bilge level alarm together with automatic bilge pumping, proved to correct action.
7. Main and stand-by electric power supply to overall alarms and monitoring system inspected and tested.
8. Complete inspection and test of fire detection and alarm system.
9. ME control will function correctly and tested from bridge position, main control room and emergency position alongside the engine.

For Tankers / Gas Carrier:
– Electrical equipment in hazardous area is surveyed every year, during each Docking Survey and Annual Survey.

Alternator Survey:
Required conditions for Surveyor:

  • Main and emergency generators are cleaned.
  • Show stable operation when run in parallel with other generator.
  • Generator windings on stator and rotor must be free of dust, rust, oil and moisture.
  • Visual check made for any obvious deterioration, abrasion, and cracking of insulation around winding coils in stator.
  • The insulation test to earth and between stator phase windings is done while the machine is still hot after running on load.
  • Air gap between stator and rotor checked to ensure that pedestal bearings are in good condition.

Switchboard Survey:
1. Thorough cleaning internally and externally at switchboard, when all generators are stopped and their prime movers locked off.
2. Main bus bar and their connections checked for tightness.
3. Bus bar supports, checked for damage due to insulation material.
4. Overheating signs at connection junctions, due to loose joint.
5. Internal wiring securely fixed.
6. Cable entries at switchboard bottom, sealed with non-flammable material.
7. Earth bar, securely bonded to both frame and to the ship’s hull.
8. Hinged panel door bonded with an earth strap to main switchboard frame.
9. Insulation resistance of each terminal measured.
10. Voltmeters, Watt meters and Ammeters calibrated and tested.
11. All trips tested [Safety devices].
12. Synchronising test [load sharing] demonstrated.
13. Earth lamps checked.
14. Automatic circuit breaker (ACB) and Automatic voltage regulator (AVR) tested.

Emergency Power and Associated Equipment Survey:

1. Emergency generator started manually and automatically.
2. Electrical supplies from emergency switchboard, checked for their proper voltage, ampere and frequency.
3. Correct functioning of emergency lighting, fire pump, and other electrical equipment.
4. Electrical interlocking arrangement between main and emergency switchboard checked.
5. Emergency battery installation and its charging rectifier checked.
6. Keep battery environment dry and well ventilated, battery tops cleaned, electrolyte at proper level and have correct value of specific gravity by checking with hydrometer.
7. Battery charging equipment checked for dirt, overheating, loose connection and correct functioning of indicator instruments.
8. Battery locker ventilation arrangements should be checked.

Insulation Resistance Survey:
1. Survey will require a list, which shows the results of recent insulation tests on all 440V and 220V main circuits.
2. The list should also indicate the test date, weather condition, hot or humid etc. together with any comment relevant to the test conditions such as machine is hot or cold.

Navigation light indicator survey:
1. Surveyor will ensure that Navigation light indicator operates correctly and has appropriate alarm.
2. Broken wire or lamp can be simulated by pulling appropriate fuse.
3. Power source for navigation lights must be duplicated [usually alternate power supply being used from Emergency Switchboard].
4. Changeover facility for power source, to be checked.
5. Although the actual light fitting for Navigation is part of Safety Equipment Survey, the Electrical Survey will naturally include a check on the supply cables to the Navigation lights.

COC ORAL EXAM PREPARATION (PART- I) – MACHINERY

MAN-B&W-K98MC-74760kw
Source: MAN Diesel (MAN-B&W-K98MC)

Cylinder liner wears:
1) Normal frictional wear: Due to metal to metal contact with high surface asperities under
marginal lubrication condition.
2) Abrasive wear: Due to presence of hard foreign particles from fuel, LO, and air.
3) Corrosive wear:Due to H₂SO₄ acid attack owing to sulphur within fuel. Only 0.1% of sulphur content causes corrosive wear, like hot and cold corrosion, and the rest carried away by exhaust gas. Sulphuric acid dew point = 120΄C to 160΄C.

Hot corrosion occurs at 460 – 570΄C.
Due to HCl acid attack, because of salts in air, charge air cooler leakage,
sea water in fuel and LO.

Other related causes:
1. Unsuitable liner material.
2. Incorrect ring clearance.
3. Misalignment of piston and liner.
4. Insufficient LO or improper arrangement of cylinder lubrication.
5. Cylinder oil having too low viscosity or alkalinity.
6. Cylinder oil containing abrasive particles.
7. Using of low sulphur fuel, in conjunction with high TBN cylinder oil.
8. Improper grade of fuel, and improper combustion.
9. Improper running-in, without high cylinder oil feed rate.
10. Overloading of engine.
11. Too low scavenge air temperature, leading to dew point corrosion.

Types of wear:

Scratching: Develop in the region of ring travel, due to small particles entrapped between the bore and rings.

Scoring: Confined to the region of ring travels and may extend to the region, swept by piston. Origin is similar to scratching.

Scuffing: Develop in ring travel, on thrust side of liner, depending on lubrication efficiency, speed and loading.

Clover Leaf Pattern: Irregular, oval or elliptical pattern of longitudinal corrosive wear, at several points around liner, concentrated between lubrication orifices or the points of LO quills. It is due to incorrect cylinder oil feed rate and acidic effect of combustion products or too low TBN cylinder oil.

– In actual practice, wear never takes place concentrically, and it depends on heel and trim of the ship in service, and effective guide clearance.
– In tankers and bulk carriers, where long ballast passage are made with the trim aft, maximum wear will be in the fore and aft plane, and especially on aft side of the liner.

Wear rate:
1. Liner wear rate is high during running-in period, after which it becomes uniform within most of its service life.
2. Finally, wear rate increases rapidly as wear becomes excessive, and due to difficulties in maintaining the rings, gas tight.
3. Wear rate can be high about 0.75 mm / 1000 hrs. in large slow speed engines, using residual fuel containing 1.5% of sulphur, in excess.
4. Wear rate being lower about 0.02 mm / 1000 hrs. in medium speed engines, due to burning low sulphur fuel oil.
5. When Vanadium is added during manufacturing, wear rate significantly reduced to the range, 0.025 mm / 1000 hrs. ~ 0.5 mm / 1000 hrs.
6. Maximum allowable wear: = 0.7 % to 1.0% of original bore, for large output engine.

Wear pattern:
» Maximum wear is at upper limit of top ring travel, at the top of piston stroke.
» This reduces towards the lower end of the stroke, but will increase in way of exhaust and scavenge ports.

Reasons of maximum wear at top of the stroke:
1. Maximum gas load behind the top ring.
2. It is a hottest region.
3. Oil film viscosity is low, and liable to breakdown under high load and high temperature.
4. Abrupt change in direction of piston rings, at dead ends of reciprocating motion.
5. More liable to be attacked by acids.

Reason of maximum wear around the ports:
» Due to leakage of hot gases, past the top ring into the ports, and these gases tend to burn off oil film.

Results of proper well-run ship:
– Good liner wear rate: < 0.1 mm / 1000 hrs. after running-in period.
– Good ring wear rate: < 0.4 mm / 1000 hrs.
– Economical level of cylinder oil feed rate: < 1.0 gm/Bhp/hr. after running-in period.

Timed lubrication:
1. Lubricators of each cylinder are synchronised with engine to provide timed lubrication.
2. Cylinder oil is fed, at the time when top two piston rings pass the oil feed points, in the cylinder during piston upstroke. [4/s and 2/s Uniflow engines]
3. Loop scavenge Sulzer RND engine use accumulator system of timed lubrication.
4. Accumulator provides constant oil pressure, which is greater than scavenge air pressure, with uniform supply at every period, around TDC and BDC positions.
5. In this way, oil is delivered to quills, only when low pressure and temperature prevails on running surface of cylinder liner.
6. 8 supply points at top, and 1 point for scavenge and 1 point for exhaust ports at bottom.

Timed lubrication has little merits, because:
1. It requires very rapid injection of oil at correct time, with correct amount, and pressure.
2. It is discharging through very small bore, with long pipes to various oil feed points.
3. Having a non-return valve at the top of lubricator, hence it complicates the timed injection.
4. The hot combustion gases tend to carbonise the oil, and block the orifices.

Reduced lubrication effects:
1. Promote wear of liner and rings.
2. Over-heating of local area causes microseizure, due to lack of boundary lubrication.
3. Consequently, major damage to liner and piston.

Excess lubrication effects:
1. Fouling of ring grooves and resulting ring zone deposits.
2. Leading to breakage of piston rings.
3. Consequently, loss of gas sealing effects and blow-by follows.
4. Scavenge space fouling and scavenge fire follows.
5. Also affecting combustion process.
6. Exhaust system and turbocharger fouling.

Cracks on cylinder liner: Causes:
1. Over-tightening of cylinder cover nuts.
2. Insufficient cooling.
3. Effects of scavenge fire.
4. High difference of working temperature.
5. Increasing of hoop stress in liner, due to slack tie bolts.
6. Misalignment of worn-out liner and piston.
7. Due to thermal stresses of metal, between exhaust ports and scavenge ports.
8. Improper fitting of liner.
9. Design failure.

Removing and refitting the liner:
Before removing:
1. Immobilisation permit taken from port authority.
2. Vessel in upright position.
3. Lifting gears and tools in good working order.
4. All spares are ready.
5. Persons grouped for assigned jobs.

Removing the liner:
1. Drain CW from cylinder jacket.
2. All lubricator quills removed.
3. Cylinder cover, piston and stuffing box removed in usual way.
4. Cover the piston rod stuffing box seating with special cover.
5. If liner is to be reused, liner wear should be measured and recorded.
6. Position of liner, relative to cylinder jacket, properly marked.
7. CW outlet pieces to cylinder cover removed.
8. Attach the liner-withdrawing tool as per instruction, and tighten the upper nut until liner comes in contact with upper supporting bar [strong back bar].
9. With overhead crane and sling arrangement, liner is drawn out.

Before refitting:
1. If old liner is to be reused, clean thoroughly.
2. Landing surface of quills checked for damage and carbon deposits in oil holes cleaned.
3. Rubber sealing ring grooves, cleaned with old round file until to bare metal.
4. Surface inside jacket, coated with anti-corrosive paint, and sitting surfaces cleaned.
5. Sharp edges inside jacket, chamfered slightly to prevent cutting rubber sealing rings.
6. If new liner is to be fitted, gauged before fitting.
7. New liner is to be lowered down into position, without sealing rings fitted, to ensure it is correct size. Liner should not only drop freely by its own weight, but there should be slight radial clearance between liner and jacket to allow for expansion.
8. Radial clearance at lower end, ≮ 0.2 mm for 750 mm bore liner.
9. Radial clearance at top, ≮ 0.001 mm / mm of liner bore.
10. Rubber sealing rings should grip firmly around liner, and a 10% stretch would be adequate.
11. If there is no original reference mark on liner, quills should be fitted and mark the correct position of liner relative to cylinder jacket.
12. Remove the liner again and sealing rings fitted.

Refitting the liner:
1. Soft soap or similar lubricant to be applied to rubber sealing rings for easy fitting.
2. Fit in correct position as per instruction.
3. New liner re-gauged after final landing to check any distortion and recorded.
4. Refit quills and test lubrication. All parts refitted in usual way.
5. Fill cylinder jacket and check water-tightness under pressure.

Running-in: During the first 10 ~ 20 hours:
1. Cylinder oil feed rate at maximum.
2. Engine load reduced.
3. Reduce oil feed rate to normal and increase the load stepwise.
4. Liner checked from inspection door and scavenge space, at first opportunity.

Safety devices on Cylinder Cover
1. Indicator cock.
2. Cylinder head relief valve. [Setting 20 ~30% above normal working pressure.]
3. Safety Cap.
4. Flame Trap.
5. Exhaust gas thermometer.

Fuel Valve:

Injector: Requirements:

1. Spray must be in atomised state, at all times, regardless of engine speed.
2. Pressure should be set at required value. [Too high – late injection: Too low – early injection].
3. Valve seat should not pass more than stated quantity of fuel, when testing, for a given period of time.
4. Valve lift should not be excessive. [Excessive valve lift can cause hammer action to valve seat, leading to permanent damage.]
5. There should be sufficient leak-off for lubrication.
6. Should be snap-seated and no dribbling.

Excessive Atomisation:
1. Smaller oil particles have insufficient KE, to go through combustion chamber.
2. Dense compressed air has high resistance to the motion of oil particles.
3. Smaller particles tend to cluster around injector tip, and oxygen-starved during combustion.
4. Can cause after-burning.

Insufficient Atomisation:
1. Oil particles become larger and will have more KE and travel further into combustion chamber, and some may rest on cylinder liner and piston crown.
2. Carbon built-up around the top of cylinder and piston crown.
3. Lower rate of combustion and after burning.

Low Penetration:
1. Less intimate mixing of air and fuel particles in combustion chamber.
2. Fuel cluster around injector tip causing after burning.

High Penetration:
1. Fuel particles travel further into the combustion chamber and some may rest on the cylinder liner and piston crown.
2. Lower rate of combustion and after burning.

Needle Scores:
Causes:
1. Due to excessive valve lift. Normal valve lift is about 1.00mm.
2. Catfines carried over from purifier and filters can cause abrasion, and needle scores.

Effects:
1. Due to needle score, fuel leakage across the seat will occur during the cut-off period. (Originally, the angle of needle valve and its seat is cut in difference of about
1°~ 2° to achieve point contact, thus preventing dribbling.)
2. Carbon formation at nozzle tip interferes the spray pattern causing poor combustion, high exhaust temperature, and increased fuel consumption.
3. In excessive case, surface burning of piston crown, too much carbon deposits in combustion space will occur.

Leak-off of a fuel valve:

1. Amount of fuel oil, which seep past the needle valve and nozzle body and it is used for lubrication.
2. Little Leak- off may seize needle in nozzle body.
3. Too high Leak-off reduce quantity of atomised fuel into combustion chamber.

Overspeed Governor:

1. Speed of ME is primarily controlled by fuel lever setting.
2. Fuel lever controls fuel pump settings, which in turn control the amount of
fuel injected / working cycle, into cylinder.
3. Speed of engine would remains constant for any fuel lever setting, provided the load on engine did not change.
4. Overspeed Governor is fitted to ME, in order to keep engine speed within reasonable limits, in the events of load change, like in heavy weather, propeller shaft fractured or propeller is lost.
5. Governor is connected with fuel pumps or fuel pump suction valves.
6. When the speed of engine rises, governor reduces quantity of fuel injected, and when the speed returns to normal, it restores the fuel pumps to the setting given by fuel lever.
7. Overspeed governor operates within ME speed limits of 5 ~ 10% below and 10% above normal speed.
8. Hand adjusting gear is fitted, so that governor setting can be altered, while engine is running.

Three types of Overspeed Governor:

1. Inertia Type. (Fitted on older slow speed engine)
2. Centrifugal mechanical Type [with spring-loaded sleeves and flyweights].
3. Mechanical hydraulic Type.

Sensitivity: Ability to control the engine speed, within narrow limits.
Stability: Governor is stable, when there is only one radius of rotation of flywheel for
each speed, at which governor operates within the speed range.
Droop: Reduction or change in speed, which occurs from no-load to full load,
is ‘governor droop’.
Hunting: When engine load changed, governor tends to over-control and under-control,
and this causes fluctuation in rotational speed, which is referred to as ‘hunting’.

Overspeed Trip:

1. Overspeed trip is fitted on engine, where governor may not be safe.
2. Its function is to shut-off fuel supply and stop the engine, when engine speed rises to dangerous level.
3. It protects the engine, when governor becomes inoperative, or shaft fractured or propeller is lost.
4. Mechanism has to be manually reset, before engine can be started again.

Trunk engine piston seizure:
Causes:
1. Blocked coolant supply to piston.
2. Overheating of the unit.
3. Exhaust valve damaged.
4. Rings damaged.

Burning away of piston crown:
Causes:
1. Piston’s inside cooling gallery, fouled with deposits.
2. Incorrect spray angle of fuel valve.
3. Injection viscosity too high.
4. Fuel containing excess amount of water. [Maintain separation temperature 98°C and minimum throughput.]

Corrosion of crank pin:
Causes:
1. L.O. contaminated with SW or FW, due to leakage. [ When combustion products, SO₂, enter crankcase, through blow pass ( trunk type) or defective diaphragm (crosshead type), they react with water and form H₂SO₄ and attack crankshaft.]
2. By galvanic action, when crankcase LO is contaminated with SW.
3. Faulty purification system cause LO contaminated with FW.
4. Piston cooling system, leaking into crankcase.

White metal bearing failure:
Causes:
1. Edge carrying wear [Due to out of true of bearing bore, or deviation from journal geometry]
2. Striations wear [Striation and embedding of foreign particles on running surfaces.]
3. Overheating of layer [Due to lack of lubrication and contamination of LO.]
4. Erosion wears [Some abrasive particles carried along with LO.]
5. Electro erosion [If crankshaft is inadequately grounded.]
6. Corrosion [Contamination of LO with SW.]

Broken piston ring:
Causes:
1. Insufficient ring and groove clearance [Vertical clearance: 0.4 mm for top ring: 0.2 mm for lower rings.]
2. Insufficient ring gap. [Butt clearance: 0.5% of cylinder bore, for moderate rating and 1.0% for higher rating. Over 500 mm bore.]
3. Excessive liner wears.
4. Excessive relieving at ring edge. [Oil wedge action cannot be attained.]
5. Insufficient lubrication.
6. Excessive lubrication. [Excessive ring zone deposits and fouling of grooves and microseizure may occur.]
7. Improper ring material.
8. Misalignment of piston.
9. Improper fitting.
10. After burning.

Indicator Diagrams:

Taken at every month and every major O/H.

Power card: In phase with piston movement, with fuel on, to determine:
IP (Indicated Power)
Pmax (Between Atmospheric line and highest point)
Operational faults.

Draw card: 90° out of phase with piston movement, with fuel on, to determine:
Pmax
Pcom (more accurately)
Nature of expansion curve.
To evaluate injection, ignition delay, fuel quality, combustion, loss of
compression, expansion process, fuel pump timing, and after-burning.

Compression card: In phase and fuel cut-off, to determine:
Compression pressure
Cylinder tightness.

Light spring : In phase, using light spring, with fuel on, to determine:
Pressure variation during Exhausting and Scavenging periods.

How to maintain good Performance:

1. Maintain good power output per cylinder.
2. Take Power Card, to check Power Output / Cylinder.
3. Take Compression Card, to check for cylinder tightness.
4. Check ratio of Absolute Compression Pressure to Absolute Scavenging Pressure.
5. If the ratio is same as that during Sea Trial, Piston rings and exhaust valves are sufficiently tight. (With B&W engine, this ratio is about 30.)
6. If Absolute Pressure Ratio is less, check for cylinder tightness, charge air cooler,
scavenge air ports, scavenge valves, piston rings, exhaust valves, TC, etc.
7. Light Spring Diagram is taken if necessary.
8. Check Exhaust Temperatures, exhaust smoke, Load Indicator and engine running parameters.
9. Check fuel, CLO & LO consumption.
10. Regular maintenance works and repairs.

Absolute Pressure = Gauge Pressure (of Manometer) + Atmospheric Pressure (15 psi or 30″ Mercury)

If Compression Pressure is low:

1. Carry out Unit O/H and renew liner, piston and rings.
2. TC checked, clean and overhauled, to have efficient operation.
3. Check Scavenge air line, charge air cooler, for insufficient scavenge air condition.
4. Check Inlet and Exhaust valves may be leaking.
5. Clean Scavenge Ports, Scavenge Valves, if 2/S engine.

Early combustion:
Causes:
1. Cetane no: of fuel higher than normal.
2. Fuel pump plunger set too high.
3. Incorrect adjustment of fuel cam on camshaft. Fuel valve ē low-pressure setting.
Effects:
1. High Pmax.
2. Low expansion line.
3. Less S.F.O.C.
4. Low exhaust temperature.
5. Heavy shock load to bearings.
6. Knocking.

Late combustion:
Causes:
1. Cetane no. of fuel lower than normal.
2. Plunger set too low.
3. Incorrect adjustment of fuel cam on camshaft.
4. Leaky fuel valves or high-pressure setting.
Effects:
1. Loss of power.
2. High expansion line.
3. Increased S.F.O.C.
4. High exhaust temperature.
5. Overheating
6. Lubrication difficulty.

Cetane Number:
1. A measure of ignition quality of fuel.
2. The higher the Cetane Number the shorter the time between fuel injection and rapid combustion.
3. The higher the Cetane No. the better the ignition quality.
4. Considered as poor fuel, if C  37 . Usual range is 30 – 45.

High Cetane no: Effects:
1. Shorter delay period
2. Early combustion
3. Increased power
4. Knocking

Low Cetane no: Effects:
1. Longer delay period
2. Late combustion
3. Decreased power
4. After burning
5. High exhaust temperature and smoke.

Diesel Knock:
– Violent knocks produced by high rate of pressure rise, RPR, during combustion, as delay period is longer than normal.
Causes:
1. Too low working temperature.
2. Cold start.
3. Too early fuel injection.

2 Stroke Crosshead Type and 4 Stroke Trunk Engine Comparison:

Crash Stop or Crash Manoeuvring:

1. Emergency reversing of engine when ship speed is high.
2. After fuel is cut off, engine revolution is waited until reversible rpm is reached.
3. Shift reversing lever to Astern position.
4. When engine rpm drops to about 45 rpm, at least one impulsive application of starting air must be applied.
5. Then engine can be started in Astern direction, as usual way.

Super Long Stroke Engine:

Advantages:

1. Increased stroke / bore ratio: 3:1
2. Reduced SFOC about 6 %.
3. Improved propeller efficiency about 2 %.
4. Simple liner construction, and low cost.
5. Thin walled liner and improved jacket cooling efficiency.
6. Simple cooling water sealing.
7. No temperature gradients across scavenge ports and exhaust valve.
8. Shorter piston skirt.
9. With uniflow scavenging, improved scavenge efficiency.

First Start Arrangement:

Emergency Air Compressor is:
a) Battery started b) Hand crank type
Note: [ If prime mover is motor, it is associated with Emergency Generator and not a first start arrangement]

1. Emergency air bottle is filled by Emergency hand air compressor.
2. During this time, one of the generators should be standing-by such as priming the LO, fuel oil, turning the flywheel, etc.
3. Start this generator and check running condition. If satisfactory, close the Main Circuit Breaker of concerned Switchboard.
4. Run cooling service pump for generator.
5. Run main Air Compressor and fill-up Air Reservoir.
6. Prepare the remaining generator, and start, equalised and load-shared.
7. Auxiliary boiler should be started.
8. ME warmed-up for operation.

Why Centrifugal Pump is used in JCW system?
1. Continuous flow.
2. Larger volume of water can be circulated.
3. Driving power can be AC or DC.
4. Self-priming obtained from Header Tank.

Standard Spares:
– Spares of the machinery, which must be provided onboard by Class Requirement.
– For ME, one unit spare, 6 links of chain for chain-drive engine, one complete set of gears for gear-drive engine, one set of thrust pad for each side.
– For AE, spares for half of the total units.

Ship Trial Results:

  • It is important for future reference.
  • When the ship is on maiden voyage, speeds, load, SFOC, etc. should be compared with ship trial results and any deviation must be claimed.

Log Book:

  • Log Book is a lawful and valuable record book.
  • All entries are to be made accurately.
  • All records are required for troubleshooting and preventive maintenance.
  • They form part of an insurance claim.

Log Book is inspected:

  • To determine conditions of ME and Auxiliary machinery performances.
  • To know ROB of fuel oil and LO.
  • To know running hours of main and auxiliary machinery.
  •  To check records concerning with SOLAS and MARPOL requirements.

Pyrometer:

1. An instrument used to measure temperature, higher than that can be measured by thermometers.
2. Platinum resistance thermometer, makes use of increased resistance of platinum wire, when rise in temperature. [ Used up to 600°C ].
3. Pyrometers’ temperature range: 600°C to 1500°C.

Thermometer:

1. Liquid in glass.
2. Liquid in metal.
3. Electrical thermometer.
4. Bi-metal strip.

Liquid in glass:
1. Thin walled glass bulb and capillary tube, completely filled with Mercury (boiling point 357°C at atmospheric pressure), at high temperature, to exclude the air.
2. The space above Mercury is filled with high pressure CO₂ gas, to extend the temperature range to about 550°C.
Mercury: Thermometer range: – 37°C to + 510°C
Alcohol: Thermometer range: – 79°C to + 71°C

Manometer:

1. Used for measuring of very small pressure.
2. Simplest form is glass ‘U’ tube containing water, and one end is open to atmosphere while other end is connected to the medium to be measured.
3. Difference in height of water records gauge pressure of medium.
{ Absolute Pressure = Gauge Pressure + Atmospheric Pressure }

Barometer:

1. Instrument for measuring atmospheric pressure.
2. As the pressure is around 15 psi Mercury fluid is used.
3. Approximately 1 psi = 2″ column of Mercury, hence 15 psi = 30″ Mercury
( Average Atmospheric Pressure).
4. One end of the tube is sealed and vacuum, and other end is open to atmosphere.

Pneumercator tank gauge:

1. Operates on ‘U’ tube principle.
2. Difference in head pressures between oil in tank and equal column of air, is transmitted by air pressure to mercury Manometer, which is graduated to read tons of oil in tank.
3. Fitted in tanks, which are not convenient to use gauge glass or sounding tape.

Compound Gauge:

1. Designed to register either vacuum or pressure.
2. Used on suction side of refrigerating plant and on evaporator.

CO₂ Recorder:

1. Electrical (type) recorder operates on Whetstone Bridge principle.
2. Two resistance on opposite sides of the Bridge are exposed to Exhaust Gases.
3. In the gas line between these two resistance is a container filled with CO₂ absorbing chemical, Caustic Potash.
4. First resistance is in contact with normal exhaust gas with CO₂ content, and after absorber, second resistance is in contact with exhaust gas without CO₂.
5. The Bridge is now unbalanced due to difference in thermal conductivity, set up by gases with and without CO₂.
6. Galvanometer is calibrated in CO₂ %.

Materials of major parts:

1. Cylinder head Chrome molybdenum steel.
2. Cylinder liner Vanadium cast iron.
3. Piston ring Chromium nickel alloys.
4. Piston Chrome molybdenum steel / Silicon Aluminium Alloy (Pielstick)
5. Piston rod Forged steel.
6. Crosshead pin Highly polished, flame hardened forged steel.
7. Bearings Thin walled bearing of tri-layer, steel backing lined with
copper-lead interlayer and lead-tin overlay.
8. Crankshaft Cast steel (cast in nodular iron).
9. Bed plate Fabricated steel / Cast steel.
10. Frame Cast steel, Fabricated mild steel.

Hanging-up an engine unit:

Circumstances in which it would be necessary to hang-up an engine unit, are:

1. Piston is seized and no spare, and if serious grooving were found on cylinder liner.
2. Cylinder liner is damaged and no spare onboard.
3. The ship is cruising in heavy sea and changing the liner is a risky problem.
4. Engine cannot be operated without removing the piston; even the defective cylinder has been cut-off.
5. Cross head bearing or bottom end bearing or guide shoe damaged and no spare.
6. Push rod and rocker arm damaged and no spare.
7. It is impossible to continue long navigation with the engine unbalanced and severe vibration due to one unit cut-off.
8. It is necessary to enter the nearest port ( port of refuge ) for repair.

Hanging-up procedure: ( Mitsubishi UEC 52 HA )

1. Cylinder cover is removed, piston is drawn out with stuffing box.
2. Blind cover is fitted to oil outlet, on top of cross-head pin.
3. Blind flange is fitted to piston rod stuffing box seating.
4. Push rod and exhaust valve driving gear removed and blank plate fitted.
5. Blind plug fitted at lubricating pipe for exhaust valve driving gear.
6. Starting air branch pipe for corresponding unit, removed at cylinder cover and blank flange fitted.
7. Plugged the starting air control valve outlet of corresponding unit.
8. Then the cylinder cover is reinstalled in regular manner.
9. Fuel injection pump of concerning unit, cut-off and shut the fuel inlet and return valves.
10. Cylinder feed rate is adjusted to zero to that unit by means of adjusting knob.

Precautions:
1. For easy starting, one of the undamaged pistons, placed at TDC by means of turning gear.
2. Severe vibration may occur within the operating range, thus appropriate engine speed should be decided by observing engine condition.
3. Pmax and exhaust gas temperatures, not to exceed the limited values at MCR.

Port of refuge:
A port to where a vessel sails in order to seek a safe place, for necessary repair, when a vessel suffers from stresses of weather or other unforeseen hazards of the sea, to its cargo or hull, or machinery.

Critical Speed: When engine is revolving at such a speed, when working stroke of the various pistons synchronises with one of the natural frequency of crankshaft, that speed is called Critical Speed. It can cause resonance condition and severe vibration.

Economy Speed: It is a speed within the range of maker’s recommended speeds, which is reasonable and effective with less specific fuel oil consumption.

Maximum continuous rating, MCR: Practical limit of diesel engine output, which is to be run continuously. (Practical output limit of diesel engine, for continuous operation).

Continuous service rating, CSR: Power output of an engine, which will be obtained during normal sea service condition, on a continuous basic.

Barr Speed: A few revolutions before and after critical speed, where it is unsafe for continuous operation of an engine due to severe vibration. [74 ~ 96 rpm]

Scavenging:

  • Process of exchanging the gases in cylinder, after expansion, with a fresh air charge.
  • In general Scavenge period has 3 phases:
    1) Exhausting begins, when Exhaust valve or ports are opened.
    2) Scavenging begins, when Scavenge ports are opened.
    3) Recharging.
    [ It is required that: 14.4 lb. of fresh air / lb. of fuel burnt.]

Method of Scavenging:
1. Uniflow Scavenging
2. Loop Flow Scavenging
3. Cross Flow Scavenging

Uniflow Principle:

1. Air enters cylinder through the ports, located at underside of cylinder.
2. Ports are arranged tangential to one another, and ensure controlled and predetermined scavenge air swirl.
3. Exhaust gases leave through centrally located exhaust valve, at upper end of cylinder.
4. Inflowing scavenge air swirl acts like ‘piston’ of fresh air, scavenging and refilling the cylinder with fresh air.
5. Used in Sulzer RT, B&W, Mitsubishi UE and Doxford engines.

It is the best scavenging method:
a. Scavenging Efficiency of Uniflow above 90%
Loop flow 80 ~ 90%
Cross flow 75 ~ 80%
b. Low cylinder liner wear
c. Low flow resistance
d. Low heat load
e. Effective fuel distribution
f. Safe low load operation.

Disadvantages:

a. Some fresh air charge is lost in exhaust gas, during overlapping time of exhaust valve opening.
b. Additional driving gear for exhaust valve required.

Pulse pressure system:

1. Makes full use of high pressure and temperature of exhaust gases during blow down period.
2. Exhaust gases leave the cylinders at high velocity, as pressure energy is effectively converted to kinetic energy to create pressure pulse in exhaust pipe.
3. Exhaust pipe, so constructed in small diameter, is quickly pressurised and boosted up to form pressure pulse or wave.
4. Pressure waves reach to turbine nozzles and further expansion takes place.

TC arrangement:
1. Interference exists between exhausting and scavenging among cylinders.
2. To prevent this, cylinders are grouped relatively with connections to two or more exhaust pipes.
3. Pipes are arranged, in small diameter to boost up pressure pulse and in short, straight length to prevent energy loss.
4. Number of exhaust branch depends upon firing order, no: of cylinders and TC design.

Advantages:
1. High available energy at turbine.
2. Good engine performance at low speed and part load.
[ Still efficient when Bmep is < 8 bar]
3. Good TC acceleration.
4. Good response to any load change.
5. Required no scavenge assistance at any load change.

Constant pressure system:

1. Exhaust gases enter into large common manifold, where pulse energy is largely lost, because receiver tends to dampen out the pulse.
2. But gas flow will be steady rather than intermittent, and at constant pressure.

TC arrangement:
1. No exhaust grouping.
2. Exhaust gases enter into large common manifold and then to turbine.
3. Firing order not considered.

Advantages:
1. High turbine efficiency due to steady flow.
2. Good engine performance at high load. [ Efficient when Bmep is above 8 bar.]
3. No exhaust grouping.
4. Reduction in SFOC of 5% – 7%.

Under piston pressure:
1. It is a type of constant pressure charging system.
2. Air charged by T/C is passed through CAC into first stage manifold, and then through non-return valves into second stage and under piston space.
3. In down stroke, piston underside compress further the scavenge air.
4. Differential pressure shuts the inlet non-return valves as scavenge ports are uncovered, and a pulse effect is given to cylinder.
Advantages:
1. Assist tangential swirl and ensure complete evacuation of remaining exhaust gas.
2. No auxiliary blower may be required, during manoeuvring.

Turbocharger cutting-off procedures:

  • When it is necessary to cut-off T/C due to heavy vibration, bearing failure, etc. cutting procedure should be done as per engine maker’s instruction.
  • Cutting-off operation depends on number of T/C installed and number of T/C damaged.
  • Following procedures are in accordance with Sulzer RT engine practice:

Case I: Failure of one T/C, with Exhaust by-pass piping:
1. Lock rotor as per T/C manual.
2. Remove blank flange in by-pass exhaust piping.
3. Open covers of scavenge air trunk.
4. Auxiliary blowers must be running during operation.
5. If casing is cracked, stop T/C cooling.
6. If T/C is supplied with external lubrication, shut L.O. supply.
Output 25%: RPM 60% at MCR.

Case II: Failure of one T/C, of two T/C engine:
1. Lock rotor of damaged T/C.
2. Remove expansion joints of both exhaust inlet and air outlet of damaged T/C, and put blank flanges.
3. If casing is cracked, stop T/C cooling.
4. If T/C is supplied with external lubrication shut L.O. supply.
Output 50%: RPM 80% : Running T/C rpm must not exceed normal rpm:

Case III: Failure of all T/C of an engine, without Exhaust by-pass piping:
1. Lock rotors of all T/Cs.
2. Open all covers of scavenge air trunk.
3. Auxiliary blowers must be running during operation.
4. If casing is cracked, stop T/C cooling.
5. If T/C is supplied with external lubrication shut L.O. supply.
Output 15%: RPM 50%:

Turbocharger Washing:

1. In Slow Speed Large Output Engines, running on HFO, only Turbine Side Cleaning is necessary, owing to poor quality fuel (but some engines use Compressor cleaning.)
2. In Medium Speed Engines, running on Distillate Fuel, Turbine Side Cleaning is not essential but Compressor Side Cleaning must be done daily, under full steaming condition.
Purpose:
1. To ensure efficient running of TC.
2. To prevent Compressor and Turbine from deposits.
3. Carried out periodically at 250 ~ 1000 Running Hours, depending on running condition.

Blower side Washing:
1. Cleaning effects by mechanical breakaway of deposits, when small drops of water strike the surface.
2. ME at normal full load speed.
3. Fixed quantity of FW is injected into air stream by compressed air, before compressor.
4. Fixed quantity used depends upon blower size, to prevent water ingress into engine.
5. Open air cooler drain and scavenge drains.

Turbine side Washing:
1. Cleaning effects by mechanical breakaway of deposits, when small drops of water strike the surface.
2. Normally carried out when the sea is calm.
3. ME speed to be reduced, with permission from Bridge.
4. Reduce ME speed avoiding critical speed.
5. Exhaust gas temperature at turbine inlet < 300°C: TC speed ≈ 2000 rpm.
6. Warm FW is supplied slowly, and pressure depends on exhaust gas temperature and volume, not to vaporise all the water.
7. Open TC casing drain and can be stopped, when clean water comes out.
8. After washing TC kept running at same reduced speed for 3 ~ 5 minutes until all parts are dry.
9. Then increase ME rpm slowly, to normal rpm.

Cereal Grains or Activated Charcoal Particles Cleaning of Turbine: [Dry Cleaning]
1. Turbine side cleaning is superseded by Coconut Charcoal particles, with grain size
of 12 to 34 mesh.
2. No speed reduction required and cleaning can be done at full speed, once every 240 hours
3. Compressed air of (3 – 5 bars) is used to help the grains strike the deposited Turbine Blades and Nozzles, giving effective cleaning of hard particles.
4. Air supply pipe is fitted to solid grain container, and grains are injected into Exhaust System by air pressure, at the same point (as in Water washing) just after Exhaust Grids.
5. Turbine casing drain kept open during cleaning time of (about 2 minutes only), until drains become clear.

Advantages of Solid Cleaning:
1. No reduction in RPM, thus no effect on scheduled voyage.
2. No water required, thus no corrosion and thermal stresses.
3. Cleaning time, shortened to about 2 minutes only.
4. Charcoal does not wear down the Turbine Blades.
5. Combustion residues and hard particles, effectively removed.

Turbocharger surging:
1. Pumping of air back to compressor, due to sudden pressure drop in compressor, below delivery pressure.
2. Prolonged surging may cause damage to compressor, thus engine speed should be lowered down until surging vanished.
3. Then faults corrected before running again full speed.
Causes:
1. One or two cylinders stop firing.
2. Faulty fuel pump or fuel valve.
3. Scavenge fire or exhaust trunk fire.
4. Sudden load change, when pitching in bad weather.
5. Dirty nozzle rings, turbine blades, impeller blades.
6. Weight loss of turbine blades due to impingement attack by Catfines.
7. Dirty blower air suction filter.
8. Incorrect matching of T/C to engine.

TC Over-run:

Causes:
1. Happened in constant pressure turbo-charged engine.
2. Caused due to fire and/or detonation of scavenge space.
3. Exhaust trunk fire due to accumulation of leaked or excess LO and unburned fuel.
Effects:
1. TC bearings, casing damaged.
2. ER fire.
Prevention:
1. Scavenge space regular cleaning.
2. Exhaust gas pipe regular cleaning.
3. Maintain complete combustion of fuel.
4. Liner, piston and rings, fuel valves, cylinder lubrication, maintained in good order.
5. Avoid operating ME under reduced load for long term.

Turbocharger Overhauling: [VTR 161, 201, 251, 321]

1. Drain bearing LO.
2. Remove bearing cover, oil suction pipe, as per Maker’s Instruction.
3. Take ‘K’ value, and compare the value with stamped one on bearing cover.
4. Take out locknuts (hexagonal screws), lubricating disc, and bearings from both sides.
After removing Rotor shaft:
1. Decarbonize Turbine and Blower blades, and check the blade condition.
2. Check Labyrinth seals.
3. Check bearing clearances: 0.2 ~ 0.3 mm for Axial: 0.15 ~ 0.2 mm for Radial:
4. Check Nozzle Ring condition.
After refitting Rotor assembly:
1. Push Rotor from Turbine side to Blower side, and measure ‘K₁’ at Blower side.
[‘L’ = 0, at this time]
2. Push Rotor from Blower side to Turbine side, and measure ‘K₂’ at Blower side.
[‘M’ = 0, at this time]
After adjusting Rotor’s smooth optimum rotation:
1. Secure the locknut (hexagonal screw) of Blower side bearing.
2. Measure ‘K’ value at Blower end. [By Depth Micrometer or Calliper and Straight Edge].
3. Calculate ‘L’ and ‘M’ values.
[L = K – K₁] and [M = K₂ – K] and compare them with actual values.
Safety Devices in Machinery Space:

Safety devices on ME:
1. Crosshead bearing temperature sensor and alarm. (Slow down)
2. Main bearing temperature sensor and alarm. (Slow down)
3. LO return line temperature sensor and alarm. (Slow down)
4. Oil mist detector, for crankcase. (ME stopped)
5. Scavenge air temperature sensor and alarm. (Slow down)
6. High exhaust temperature sensor and alarm. (Slow down)
7. High FW temperature sensor and alarm. ( Slow down / ME stopped)
8. Low LO pressure alarm. (Slow down)
9. Low FW pressure alarm. (Slow down)
10. Turning Gear interlock.
11. Overspeed trip.
12. Emergency Manual Stop.
13. Micro computerised Safety Panel for Auto Slow down and Shut down arrangements.
14. Relief Valves on:
a) Cylinder head.
b) Scavenge trunk
c) Crankcase
d) Fuel pump and system
e) Start air line
15. Cylinder Lubricator failure alarm and Cylinder oil no-flow alarm.

Safety devices on Electrical Heaters: FO, LO.
1. HT cut-out switch, which switch off the supply.
2. Temperature sensor and auto switching device.

Safety devices on AC Main Switchboard:
1. Over current relay.
2. Reverse power relay
3. Short circuit relay
4. Preferential trip.

Windlass safety devices:
1. Overload [thermal switch]
2. Over speed trip
3. Slipping clutch.

Winches brake adjustment: Adjust the distance between friction plate and pressure plate.

Lifeboat safety devices:
1. Limit Switch [while lifting]
2. Centrifugal Brake [while lowering]

Safety devices on Steering Gear:
1. Low oil level alarms on each power unit reservoir tanks.
2. Overload alarm.
3. Power failure alarm.
4. Relief Valves in power unit hydraulic system and telemotor unit hydraulic system.
(Set pressure 20 – 30% above Normal Working Pressure.)
5. Double shock valves. (Set to lift at about 100 bar, 10% above NWP: allowed rudder to give way when subjected to severe shock from heavy sea.)
6. Suitable working access to Steering Gear Room and Control, with guardrails and non-slip surface.
7. Quick response in 30 sec. from hard over to hard over, at full speed.
8. A fixed oil storage system.

Safety devices on Main Air Compressor:
1. Bursting Disc on Intercooler: (At waterside)
2. Bursting Disc and Fusible Plug (121°C) on Aftercooler
3. Automatic Moisture Drain Valve.
4. Relief valves on LP and HP stages. (Set to lift at 10% rise above normal stage pressure.)
5. Cooling water supply failure alarm.
6. Low LO pressure alarm.
7. Relief valve on crankcase LO pump.
8. Delivery air HT alarm on Aftercooler outlet. (Max. 93°C)
{LP discharge pressure 4 bars: HP discharge pressure 30 bars:
Intercooler inlet air 130°C: Intercooler outlet air 35°C:
Aftercooler inlet air 130°C: Aftercooler outlet air 35°C:
Intercooler is single pass type: Aftercooler, double pass U-tube type:}

Safety devices on Main Air Bottle:
1. Fusible plug.
2. Pressure Relief Valve
3. Low Air Pressure alarm.
4. Atmospheric Relief Valve.
5. Automatic or remote control Moisture Drain Valve.

Safety devices on Boiler:
1. Two nos. of Safety Valves.
2. Low and high Water Level alarms with transmitter.
3. Low and high FO Temperature alarms.
4. Low FO Pressure alarm.
5. Low Steam Pressure alarm.
6. Easing Gears on Safety Valves.
7. Fusible Plugs.
8. 2 Water Level Gauge Glasses.
9. Remote Water Level Indicators.
10. Flame Failure alarm.
11. Smoke Density alarm.
12. Air/fuel Ratio alarm.

Safety devices on Fridge Plant and Compressor:
1. Liquid Shock Valve on Cylinder Head.
2. Busting Disc on Cylinder Head, between Suction and Discharge manifold.
3. Gas LP cut-out.
4. Gas HP cut-out.
5. LO LP cut-out.
6. CW LP cut-out.
7. Relief Valve on Condenser.
8. Bursting Disc on Condenser. (if fitted)
9. Non-return Check Valves on each gas return line to Compressor.

Miscellaneous Calculations:

Specific Fuel Oil Consumption, SFOC.

SGc = Corrected specific gravity of fuel at measuring point temperature;

SGb = Specific gravity of bunker;
(Should be taken from lab report, if not taken from bunker note at 15°C )

T = Fuel oil temperature at measuring point.

SGc = SGb – [ 0.00064 (T– 15) ]

kW = Output of engine in kW.

Let daily fuel consumption is = C litres/day (obtained from Flow Meter reading)
= C/10³ m³/day
= C/10³ x SGc MT/day
= C/10³ x SGc x 10³ kg/day
= C x SGc x 10³ gm/day

C x SGc x 10 ³
SFOC = gm / kW hr
24 x kW

C x SGc x 10 ³
SFOC = gm / bhp hr
24 x BHP

This initial specific fuel consumption should be corrected for 3 factors:
i. Difference between actual scavenge air temperature and system standard of 45°C.
ii. Difference between actual turbo blower air inlet temperature and
system standard of 27°C.
iii. The net specific energy of fuel .

If daily fuel consumption is = C MT/day

C x SGc x 10⁶
SFOC = gm / kW hr
24 x kW
Specific Cylinder Lubricating Oil Consumption:

qa = Actual feed rate, gm / kW-hr.
Q = Measured value, litre / day
r = SGc, Corrected specific gravity of oil at measuring point temperature.
Le = Engine output, in kW

Q x 1000 x r
qa = gm / bhp hr
24 x Le

Slip Calculation:

P = Pitch in meter
N = Total revolutions/ day ( N = 60 x 24 x r.p.m. )
Theoretical distance = ( P x N ) / 1852 Nautical miles per day.

Theoretical Distance  Actual Distance (Noon to Noon)
Slip % = x 100
Theoretical Distance

What is API scale of measurement? [FPS system]

Bunker Specific Gravity my be converted to degree API by the formula:

141.5
Degree API = – 131.5
Sp.Gr.

Degree API may be converted to Specific Gravity by:

141.5
Sp.Gr. =
at 15°C(59°F) 131.5 + degree API

Use Volume Correction Factor as per API gravity with exact oil temperature
at bunkering time.

MAIN ENGINE AIR STARTING SYSTEM

 

Diesel engine starting system

   

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ME protection system

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DIESEL ENGINE CRANKCASE EXPLOSION

INTRODUCTION:

For any fire to begin, the fire tringle needs to be completed. To complete a fire tringle there must be present of a combustible material, oxygen or air to support combustion and a source of heat in proportional ratio and within the flammable limits, the reaction which causes fire or explosion becomes cyclic.

2416324888_fbde60a9c5
Image Credit: www.brighthubengineering.com

Crankcase explosion normally occurs in trunk engine in which the lubricating oil used in the bearings is splashed around the crankcase and broken down into moderate size particles.
The main cause of crankcase explosions are the development of hot spots at various places in the crankcase. Due to the reciprocating motion of the piston the lubricating oil in the crankcase is splashed in the air.

346
Image Credit: www.marinediesels.info

Possible causes of “hot spots” in diesel engines:
 Failure of oil supply
 Bearing journal surfaces becoming too rough due to L.O. becoming corrosive or being polluted by abrasive particles
 Atomization of circulating oil, caused by a jet of air/gas by combination of the following:
– Stuffing box leakages (not air tight)
– Blow-by through a cracked piston crown or piston rod (with direct connection to crankcase via the cooling outlet pipe)
– As a result of heat from a scavenge fire being transmitted down the piston rod via the stuffing box
2 stroke risk areas
Image Credit: www.marinediesels.info

When there is a hot spot formed example a bearing, guide, connecting rod, piston trunk or skirt become overheated, the falling oil particles to the heated area easily vaporize and form a white vapour (in addition some is broken down to flammable gasses such as Hydrogen and acetylene) which spreads around the crankcase.
Some of the vapour condenses to form very small particles (up to 200 micro meters in diameter) which may eventually permeate or travel the away from hotspot to whole of the crankcase space. The condensed droplets, form a dense white mist If the mixture of air, very small particles and vapour reaches a certain proportion and the temperature of the hot spot is high enough to initiate combustion an explosion can occur (850°C to ignite oil mist).
Although the most common cause of of a localized hotspot is due to friction, it is not the only cause of a crankcase explosion. A cracked piston crown, blow-by or an external fire have caused crankcase explosions in the past.
If the mixture of oil vapour, particles and air too rich (due to some reason or possibility air can be drawn in so creating the environment for a second and possible larger explosion.

EXPLOSIONS – PRIMARY AND SECONDARY

PRIMARY EXPLOSION:
 Over a period of time the formation of mist starts increasing and when sufficient air/fuel ratio is reached i.e. high enough to exceed the lower explosion limit, the mist comes in contact with the hot spot again and in the presence of sufficient temperature results into an explosion.
 The extent of explosion will depend upon the amount of mist produced inside. The primary explosion might be mild and sufficient enough to lift the crankcase relief valves but there could be more severe and dangerous effects during secondary explosion.
348
Source: www.marinediesels.co.uk

SECONDARY EXPLOSION:
 When an explosion occurs a flame front travels down the crankcase with a pressure wave in front of it.
 The turbulence caused by moving engine components causing churning and mixing of vapours increase the speed of the flame front and its area, which contribute to the increase in pressure.
 Turbulence caused by venting of the pressure through relief valves can also influence the explosion.
 Following the venting of the explosion through the relief valves, there is a drop in crankcase pressure to below atmospheric pressure. This can cause air to enter the crankcase resulting in another flammable mixture to be developed resulting in a secondary explosion to occur.
 The secondary explosion is more violent and can result in crankcase doors being blown off the engine, and fires starting in the engine room. If the relief valves do not reseal after lifting, or if they do not lift at all in the primary explosion ( due to lack of maintenance etc), then door(s) may be blown off in the primary explosion, giving a ready path for the ingress of air, which will make a secondary explosion more likely.
 Air can also be sucked in via the crankcase vent, although rules state that this must be as small as practicable and new installations must have a non return valve fitted.

INDICATION OF CRANKCASE EXPLOSION:

It is a bit difficult to read the early signs of a crankcase explosions. This is because the indications are similar to many other emergency situations. But there are few pre-explosion signs that can be read. Crankcase explosion will lead:
 Sudden increase in the exhaust temperature
 Sudden increase in the load on the engine
 Irregular running of the engine
 incongruous noise of the engine
 smell of the white mist.
In case of these indications, engine speed should be brought down immediately and the supply of fuel and air should be stopped. The system should then be allowed to cool down by opening the indicator cocks and turning on the internal cooling system.

MEASURES TO BE TAKEN WHEN OIL MIST HAS OCCURRED

 Do not stand near crankcase doors or relief valves – nor in corridors near doors to the engine room casing!
 Reduce speed/pitch to slow-down level, if not already carried out automatically
 Ask the bridge for permission to stop
– Measures to be taken when Oil Mist has occurred
 When the stop order is received:
– Stop the engine
– Close the fuel oil supply
 Switch-off the auxiliary blowers
 Open the skylight and/or “stores hatch”
 Leave the engine room
– Measures to be taken when Oil Mist has occurred
 Lock the casing doors and keep away from them
 Prepare the fire-fighting equipment
 Do not open the crankcase until at least 20 minutes after stopping the engine. When opening up, keep clear of possible spurts of flame. Do not use naked light and do not smoke.
– Measures to be taken when Oil Mist has occurred
 Stop the circulating oil pump. Take off/open all the lowermost doors on the side of the crankcase. Cut-off the starting air and engage the turning gear.
 Locate the “hot spot”. Use powerful lamps from the start.
 Keep possible bearing metal found at the bottom of oil tray for later analyzing.
– Measures to be taken when Oil Mist has occurred
 Prevent further “hot spots” by preferably making a permanent repair.
 Ensure that the respective sliding surfaces are in good condition
 Take special care to check the circulating oil supply is in order.
– Measures to be taken when Oil Mist has occurred
 Start the circulating oil pump and turn the engine by means of the turning gear.
 Check the oil flow from all bearings, spray pipes and spray nozzles in the crankcase, chaincase and thrust bearing.
 Check for possible leakages from piston or piston rods.

PREVENTION

Prevention of crankcase explosion can be done by preventing the generation of hot spots. It can also be prevented by the following ways:
 By providing proper lubrication to the reciprocating parts,thus avoiding high temperatures.
 Avoiding overloading of the engine
 Using bearings with white metal material which prevents rise in temperature.
 Using oil mist detector in the crankcase with proper visual and audible alarm.Oil mist detectors raise an alarm if the concentration of oil mist rises above the permissible limit.
 Pressure relief valves should be fixed on the crankcase for the instant release of pressure. They should be periodically pressure tested.
 Crankcase doors should be made of strong and durable material. Vent pipes shouldn’t be too large and should be checked for any choke up
 Pressure relief valves should be provided with wire mesh to prevent the release of flames inside the engine room.
 Safe distance should be kept from the crankcase and the relief valves in case the indications are sighted.
 In case of indication, the crankcase doors should never be opened till the time the system has totally cooled down. Once the system has cooled down, proper inspection and maintenance should be carried out.
Fire extinguishing medium should be kept standby. In many systems, inert gas flooding system is directly connected to the crankcase.

Crankcase safety fittings

•  Crankcase Relief valves
•  Vent pipes
•  Alarms
•  Warning notice
•  Fire-extinguishing system for scavenge manifolds

Relief Valves

 The valve lids are to be made of ductile material capable of withstanding the shock of contact with stoppers at the full open position.
 The discharge from the valves is to be shielded by flame guard or flame trap to minimize the possibility of danger and damage arising from the emission of flame.

Number of Relief Valves

 In engines having cylinders not exceeding 200 mm bore and having a crankcase gross volume not exceeding 0,6 m3, relief valves may be omitted.
 In engines having cylinders exceeding 200 mm but not exceeding 250 mm bore, at least two relief valves are to be fitted; each valve is to be located at or near the ends of the crankcase. Where the engine has more than eight crank throws an additional valve is to be fitted near the centre of the engine.
 In engines having cylinders exceeding 250 mm but not exceeding 300 mm bore, at least one relief valve is to be fitted in way of each alternate crank throw with a minimum of two valves. For engines having 3, 5, 7, 9, etc., crank throws, the number of relief valves is not to be less than 2, 3, 4, 5, etc., respectively.
 In engines having cylinders exceeding 300 mm bore at least one valve is to be fitted in way of each main crank throw.
 Additional relief valves are to be fitted for separate spaces on the crankcase, such as gear or chain cases for camshaft or similar drives, when the gross volume of such spaces exceeds 0.6 m3.

Size of Relief Valves

 The combined free area of the crankcase relief valves fitted on an engine is to be not less than 115 cm2/m3 based on the volume of the crankcase.
 The free area of each relief valve is to be not less than 45 cm2.
 The free area of the relief valve is the minimum flow area at any section through the valve when the valve is fully open.
 In determining the volume of the crankcase for the purpose of calculating the combined free area of the crankcase relief valves, the volume of the stationary parts within the crankcase may be deducted from the total internal volume of the crankcase.

Vent Pipes

 Where crankcase vent pipes are fitted, they are to be made as small as practicable to minimize the inrush of air after an explosion. Vents from crankcases of main engines are to be led to a safe position on deck or other approved position.
 If provision is made for the extraction of gases from within the crankcase, e.g. for oil mist detection purposes, the vacuum within the crankcase is not to exceed 25 mm of water.
 Lubricating oil drain pipes from engine sump to drain tank are to be submerged at their outlet ends. Where two or more engines are installed, vent pipes, if fitted, and lubrication oil drain pipes are to be independent to avoid intercommunication between crankcases.

Alarms

 Alarms giving warning of the overheating of engine running parts, indicators of excessive wear of thrusts and other parts, and crankcase oil mist detectors are recommended as means for reducing the explosion hazard. These devices should be arranged to give an indication of failure of the equipment or of the instrument being switched off when the engine is running.

Warning Notice

 A warning notice is to be fitted in a prominent position, preferably on a crankcase door on each side of the engine, or alternatively at the engine room control station. This warning notice is to specify that whenever overheating is suspected in the crankcase, the crankcase doors or sight holes are not to be opened until a reasonable time has elapsed after stopping the engine, sufficient to permit adequate cooling within the crankcase.

Crankcase Access and Lighting

• Where access to crankcase spaces is necessary for inspection purposes, suitably positioned rungs or equivalent arrangements are to be provided as considered appropriate.
• When interior lighting is provided it is to be flameproof in relation to the interior and details are to be submitted for approval. No wiring is to be fitted inside the crankcase.

Fire-Extinguishing System for Scavenge Manifolds

• Crosshead type engine scavenge spaces in open connection with cylinders are to be provided with approved fixed or portable fire-extinguishing arrangements which are to be independent of the fire-extinguishing system of the engine room.

SPECIFIC REGULATIONS

1. Non-return doors must be fitted to engines with a bore greater than 300mm, at each cylinder with a total area of 115sq.cm/m3 of gross crankcase volume. The outlets of these must be guard to protect personnel from flame. For engines between 150 to 300mm relief doors need only be fitted at either end. Below this bore there is no requirement. The total clear area through the relief valve should not normally be less than 9.13cm2/m3 of gross crankcase volume
2. Lub Oil drain pipes to the sump must extend below the surface and multi engine installations should have no connections between the sumps
3. Large engines, of more than 6 cylinders are recommended to have a diaphragm at mid-length and consideration should be given to detection of overheating (say by temperature measuring probes or thermal cameras) and the injection of inert gas.
4. Engines with a bore less than 300mm and a crankcase of robust construction may have an explosion door at either end
5. Means of detection of oil mist fitted.

Crankcase Doors

• These when properly designed are made of about 3mm thick steel with a dished aspect and are capable of withstanding 12 bar pressure. They are securely dogged (gripped) with a rubber seal arrangement.

Crankcase Relief Door

explosion-relief-valve

 Due to the heavy force of momentum the gas shockwave is not easily deflected.
 Thus any safety device must allow for a gradual change in direction, and be of the non-return type to prevent air being drawn back into the crankcase.
 The original design was of cardboard discs which provided no protection against the ingress of air after the initial explosion, in addition it was known for these discs to fail to rupture in the event of an explosion.
 The valve disc is made of aluminium to reduce inertia.
 The oil wetted gauze provides a very effective flame trap this reduces the flame temperature from 1500’C to 250’C in 0.5 m.
 The ideal location for this trap is within the crankcase where wetness can be ensured.

 The gas passing from the trap is not normally ignitable. The gauze is generally 0.3mm with 40% excess clear areas over the valve.
 Continuous extraction by exhauster fan may be used but this tends to be costly, flame gauzes must be fitted to all vents. Similarly a continuous supply of air can be used to reduce gas mist levels.

Crankcase oil mist detector

images
Source: OIL MIST DETECTOR MD-SX (Daihatsu, Japan)

 Oil mists can be readily detected at concentrations well below that required for explosions, therefore automated detection of these oil mists can be an effective method of preventing explosions.
 The Graviner oil mist detector is in common use in slow speed and high speed engines.
 The disadvantage of this type if system is that there is a lag due to the time taken for the sample to be drawn from the unit and for the rotary valve to reach that sample point.

 Consists of :-

I. Extraction fan
– draws the sample from the sample points through the reference and measuring tubes via non-return valves.

II. Reference tube
– measures the average density of the mist within the crankcase, as there will always be some mechanically generated mist.

III. Rotary valve
– this valve is externally accessible and is so marked so as to indicate which sample point is on line. In the event on exceeding the set point , the valve automatically locks onto that point so giving a clear indication of the locality of the fault condition.
IV. Measuring tube
– measures the opacity(darkness) of the sample by means of a photoelectric cell as with the measuring cell. To exclude variables in lamps a single unit is used with beams directed down the tube by mirrors.

Oil mist detector function:

oil mist detector

  •  To monitor samples taken continuously from the crankcase of a diesel engine.
  • Detect the presence of oil mist at concentrations well below the level at which crankcase explosions may occur. This gives warning in time to allow avoiding to slow down the engine and prevent either serious bearing damage or an explosion.
  • The detector consists basically of two parallel tubes of equal size each having a photo-electric cell fitted at one end. Photo-electric cells are light sensitive and generate an electric current directly proportional to the intensity of the light falling on their surface. Lenses are fitted to seal the ends of each tube but allow light to pass.
  • Two identical beams of light from a common lamp are reflected by mirrors to pass along the tubes on to the cells which are then in electrical balance.
  • One tube is sealed to contain clean air and is termed the reference tube. The other termed the measuring tube, has connections through which samples of the vapor content of the engine crankcase are drawn by means of an electrically extractor fan.
  • In the event of a concentration of oil mist being present in the sample, light will be obscured before reaching the cell of the measuring tube. Electrical balance between the two cells will be disturbed and an alarm will be operated.
  • Sampling points should be fitted to each cylinder crankcase and their connections are brought to a  rotating selector valve which is driven from the motor. This repeatedly connects each sampling point to the measuring tube in sequence.
  • In the event of oil mist being detected the rotator stops to indicate which sampling point is concerned. The instrument must be reset below the alarm ceases and sampling will recommence its sequence.

 Crankcase oil mist detector maintenance:

  • Sampling connections should not exceed 12.5 meters in length and must slope to ensure positive drainage of oil; they must avoid any loops in which could fill with oil.
  • The detector should be tested daily and the sensitivity checked. The lenses and mirrors should be cleaned periodically.

REFERENCES:

  1. www.marineengineering.co.uk
  2. The Running and Maintenance of Marine Machinery – Cowley
  3. Lamb’s Question and Answers on Marine Diesel Engines – S. Christensen
  4. Diesel Engines – A J Wharton
  5. www.marinediesels.info

DIESEL ENGINE SCAVENGE FIRE

INTRODUCTION:

For any fire to begin, the fire tringle needs to be completed. To complete a fire tringle there must be present a combustible material, oxygen or air to support combustion and a source of heat at a temperature high enough to start combustion.

Source: www.marinediesels.info

In the case of scavenge fires:
 the combustible material is oil. The oil can be cylinder oil which has drained down from the cylinder spaces, or crankcase oil carried upwards on the piston rod because of a faulty stuffing box. In some cases the cylinder oil residues may also contain fuel oil. The fuel may come from defective injectors, injectors with incorrect pressure setting, fuel particles striking the cylinders and other similar causes.
 The oxygen necessary for combustion comes from the scavenge air which is in plentiful supply for the operation of the engines.
 The source of heat for ignition comes from piston blow-by, slow ignition and afterburning, or excessive exhaust back pressure, which causes a blowback through the scavenge ports.

• A scavenge fire can cause serious damage to the piston rod diaphragm gland as well as leading to possible distortion of the air box and cracking of the liner. Tie rod tension will almost certainly be affected.
• The worst case scenario for a scavenge fire is it leading to a crankcase explosion
• The fire may also spread outside the scavenge box due to relief doors leaking or oil deposits on the hot casing igniting. For these reasons a scavenge fire should be dealt with as quickly as possible.

INDICATION

 Loss in power and irregular running of the engine,
 High exhaust temperatures of corresponding units,
 High local temperature in scavenge trunk,
 Surging of turbocharger,
 Sparks and smoke emitted from scavenge drains.
 External indications will be given by a smoky exhaust and the discharge of sooty smuts or carbon particles.
 If the scavenge trunk is oily the fire may spread back-from the space around or adjacent to the cylinders where the fire started and will show itself as very hot spots or areas of the scavenge trunk surfaces.
 In ships where the engine room is designed as UMS, temperature sensors are fitted at critical points within the scavenge spaces. So, activation would cause automatic slow down of the engine.

ACTION TO BE TAKEN WHEN SCAVENGE FIRE OCCURRED

 In the event of scavenge fire the engine must be put to dead slow ahead as soon as possible and the fuel must be taken off the cylinders affected by the fire or preferably stopped.
 The turning gear should be put in and the engine continuously turned with increased cylinder oil to prevent seizure (jam).
 All scavenge drains must be shut to prevent the discharge of sparks and burning oil from the drains into the engine room.
 Air supply should be cut off by enclosing the turbocharger inlets, for mechanically operated exhaust valves the gas side should also be operated, (hydraulically operated exhaust valves will self close after a few minutes).

For a minor scavenge fire:
–  A minor fire may shortly burn out without damage, and conditions will gradually return to normal. The affected units should be run on reduced power until inspection of the scavenge trunking and overhaul of the cylinder and piston can be carried out at the earliest safe opportunity.
–  Once navigational circumstances allow it, the engine should be stopped and the whole of the scavenge trunk examined and any oil residues found round other cylinders removed.
–  The actual cause of the initiation of the fire should be investigated

For a major scavenge fire:

–  If the scavenge fire is of a more major nature, if there is a risk of the fire extending or if the scavenge trunk is adjacent to the crankcase with risk of a hot spot developing it sometimes becomes necessary to stop the engine.
–  Normal cooling is maintained, and the turning gear engaged and operated. Fire extinguishing medium should be applied through fittings in the scavenge trunk: these may inject carbon dioxide, dry powder or smothering steam.

 The fire is then extinguished before it can spread to surfaces of the scavenge trunk where it may cause the paint to start burning if special non inflammable paint has not been used.
 Boundary cooling of the scavenge trunk may be necessary. Keep clear of scavenge relief valves, and do not open up for inspection until the engine has cooled down.

After extinguishing scavenge fire:
 After extinguishing the fire and cooling down, the scavenge trunking and scavenge ports should be cleaned and the trunking together with cylinder liner and water seals, piston, piston rings, piston skirt, piston rod and gland must be inspected.
 Heat causes distortion and therefore checks for binding of piston rod in stuffing box and piston in liner must be carried out.
 Tightness of tie bolts should be checked before restarting the engine.
 Inspect reed valves if fitted, and scavenge relief valve springs.
 Fire extinguishers should be recharged at the first opportunity and faults diagnosed as having caused the fire must be rectified.

SAFETY FITTING

  1. Scavenge belt relief door
  2. Fire Fighting Media

1. SCAVENGE BELT RELIEF DOOR:

Scavenge belt relief door Fitted to both ends of the scavenge belt and set to lift slightly above the maximum normal working scavenge air pressure.

2.  FIRE FIGHTING MEDIA
 Carbon dioxide- will put out a fire but supply is limited. Susceptible to loss if dampers do not effective prevent air flow
 Water spray- perhaps the ideal solution giving quick effective cooling effect to the fire.
 Dry powder- will cover the burning carbon and oil but is messy. As the fire may still smoulder below the powder care must be taken when the scavenge doors are removed as the powder layer may be blown away.
 Steam smothering-plentiful and effective


Source: www.marinediesels.info

PREVENTION

 Good maintenance and correct adjustment must be carried out
 Scavenge trunking must be periodically inspected and cleaned and any buildup of contamination noted and remedied.
 The drain pockets should also be cleaned regularly to remove the thicker carbonized oil sludges which do not drain down so easily and which are a common cause of choked drain pipes
 Scavenge drains should be blown regularly and any passage of oil from them noted.
 The piston rings must be properly maintained and lubricated adequately so that ring blow-by is prevented.
 At the same time one must guard against excess cylinder oil usage.
 With timed cylinder oil injection the timing should be periodically checked.
 Scavenge ports must be kept cleared
 The piston-rod packing rings and scraper rings should also be regularly adjusted so that oil is prevented from entering the scavenge space because of butted ring segments.
 This may and does occur irrespective of the positive pressure difference between the scavenge trunk and the crankcase space.
 Fuel injection equipment must be kept in good condition, timed correctly, and the mean indicated pressure in each cylinder must also be carefully balanced so that individual cylinders are not overloaded.
 If cylinder liner wear is up to maximum limits the possibility of scavenge fires will not be materially reduced until the liners are renewed

REFERENCES:
1. www.marineengineering.co.uk
2. The Running and Maintenance of Marine Machinery – Cowley
3. Reeds Marine Engineering Series, Vol. 12 – Motor Engineering Knowledge for Marine Engineers
4. Lamb’s Question and Answers on Marine Diesel Engines – S. Christensen
5. Diesel Engines – A J Wharton
6. www.marinediesels.info

LATEST DEVELOPMENT ON EU-MRV

ships_pollution
Monitoring Reporting & Verification (MRV) is a standardised method to produce an accurate CO2 emissions inventory, through the quantification of CO2 emissions. The key principles of the scheme are to generate robust results using a lean approach considering parameters which are already monitored during normal operations.
It is advocated as a way of monitoring a ship’s fuel consumption and its operational energy efficiency performance.

MRV is still under discussion in IMO and they will come up with a decision in next MEPC. The new EU Regulation 2015/757 came into force on 1 July 2015 and operating from 2018.

There is a MEPC Working Group active on the subject:
 A corresponding working group and pilot testing of various schemes are encouraged.
 Work has significantly progressed and is likely to finalise in 2016.

 

IMO MRV main elements:
 Data collection
 Data verification
 Data submission to a central database.

IMO MRV status:

  • Applicable to ships >5000 GT
  • Annual reporting
  • IMO number for ship identification
  • Guidelines will be developed to deal with various aspects.
  • Registered owner is responsible for submission of data to Administration
  • Administration responsible for verification (can be delegated to ROs).
  • A Statement of Compliance will be issued to ship annually
  • PSC will examine SFC for enforcement
  • Responsibility of reporting remains with ship
  • Transport work and other data to be decided later.

The Regulation follows the European Parliament’s Resolution of 5th February 2014, which called upon the Commission and Member States to set a binding target of reducing domestic greenhouse gas emissions by at least 40% compared with levels observed in 1990.

CO2 emissions from international shipping, related to the EU alone, increased by 48% between 1990 and 2007. However, as yet international maritime shipping remains the only means of transportation which has not been included in Community proposals to reduce greenhouse gas emissions.

In light of the developing scientific understanding of the impact of maritime transport on the global climate, it has been decided that this should be assessed regularly and that the European Commission should consider implementing policies and measures to reduce both CO2 emissions and other kinds of emissions from vessels in future. According to data provided by the IMO, the energy consumption and emissions of ships could be reduced by up to 75% by applying operational measures and implementing technologies which already exist. It is believed that the best option for reducing CO2 emissions from shipping is to set up a system for monitoring, reporting and verification (MRV) of CO2 emissions based on the fuel consumption of ships. The MRV system is set out in the form of a Regulation due to the complex and highly technical nature of the provisions introduced, the need for uniform rules applicable throughout the European Union, and to facilitate implementation of these proposals throughout the European Union.

Regulations for MRV
1. Article 4: Article 4 of the Regulation sets out ‘common principles’ for monitoring and reporting. For each ship with a gross tonnage above 5000GT, ship owners must provide a complete report covering CO2 emissions from the combustion of fuels whilst ships are at sea as well as at berth. It is important to apply appropriate measures to prevent any gaps in the data – the whole period must be covered (Article 4(2)).

The data produced must also be accurate – the burden is on the ship owner to identify the source of any inaccuracies and prevent them (Article 4(5)).

Monitoring and reporting must also be consistent. The same monitoring methods and data sets should be used so that the data acquired can be compared overtime and any increase or decrease in emissions can be accurately monitored (Article 4(3)).

The monitoring data itself must be collected and documented in a transparent manner. This will enable any independent verifier to reproduce the methods used to determine the vessel’s CO2 emissions (Article 4(4)).
2.  Article 5: Article 5 of the Regulation sets out specific methods for monitoring and reporting vessel emissions, as well as other relevant information, by reference to Annexes I and II. By Article 5(1) any of the methods set out in the Annexes may be used to determine CO2 emissions and other relevant information.

Methods for determining CO2 Emissions
It is recommended that Members look into the detailed provisions of Annexes I and II themselves. However, we include a brief summary of the key points below. Four methods for determining CO2 emissions are given in the Regulation, as set out in the following formulae: (from Annex I):
Fuel consumption x emission factor

For the emission factor, default values shall be used unless the company decides to use the fuel quality data set out in the bunker delivery note for that fuel.

For the actual consumption of fuel, Annex I provides the following approved methods:

Fig: EU-MRV scheme overview (Source: LR)

Method A: Bunker Delivery Notes and Periodic Stock-Takes of Fuel Tanks
This method is based on the quantity and type of fuel as defined in the bunker delivery notes, compared with information gained from periodic stock-takes. The fuel at the beginning of the monitoring period, plus deliveries, minus fuel available at the end of the period and de-bunkered fuel will indicate how much fuel has been consumed.
Fuel tank readings must be carried out by methods such as automated systems, soundings and dip tapes. Whichever method is used, it must be specified in the monitoring plan.

Method B: Bunker Fuel Tank Monitoring On-Board
This method is based on fuel tank readings for all the fuel tanks on board. The readings must take place daily when the ship is at sea and each time the ship is bunkering or de-bunkering. The cumulative variations of the fuel tank level between two readings will constitute the fuel consumed over the period, which might be the time between two port calls or time spent within a port.
As above, the method of taking fuel tank readings must be an ‘appropriate method’ and be specified in the monitoring plan.

Method C: Flow Meters for Applicable Combustion Processes
This method is based on measured fuel flows on board. The data from all the flow meters linked to relevant emission sources will be combined to determine all fuel consumption for a specific period. Again, the period might be the time between two port calls or time spent within a port.

Method D: Direct Emissions Measurement
This method may be used for voyages within the scope of the Regulation and emissions occurring in ports located in a Member State’s jurisdiction. For ships on which reporting is based on this method, fuel consumption will be calculated using measured CO2 emissions and the applicable emission factor of the relevant fuels.

This method is based on the determination of CO2 emission flows in exhaust gas stacks (funnels) by multiplying the CO2 concentration of exhaust gas by the exhaust gas flow.

Monitoring Plan
Under Article 6(1), by 31st August 2017 a monitoring plan must be submitted to the verifiers which indicates the method chosen to monitor and report emissions and other relevant information. Each ‘company’ must submit a separate plan for each ship to which the Regulation applies. Should ships fall within this Regulation only after the 31st August 2017, the plan must be submitted without undue delay (Article 6(2)).

The monitoring plan is meant to be a complete, transparent documentation of the monitoring methodology for the specific ship. It must contain:
a) the identification and type of ship (including its name, IMO number, port of registry and owners’ name);
b) contact details for the ‘company’ responsible for monitoring and reporting;
c) a description of the emission sources on board (the main engines, auxiliary engines, gas turbines, boilers, inert gas generators) and the fuel types used;
d) a description of procedures, systems and responsibilities used to update the list of emission sources;
e) a description of procedures used to monitor the completeness of the list of voyages;
f) a description of the procedures for monitoring fuel consumption, emission factors for each fuel type used (including how these were calculated in the case of alternative fuels);
g) a description of the procedures used to determine activity data per voyage, a description of the method to be used to determine surrogate data (in the case of data gaps); and
h) a revision record sheet to show any revisions which have been made.
As can be seen from the above this is a comprehensive document and therefore templates will be provided in order to streamline and standardise this process. The form these will take is as yet undecided, but it is indicated by Article 6(4) that these will be determined by means of implementing acts in the near future.

Under Article 7, the company is required to modify the monitoring plan in certain situations:
a) if there is a change of company (i.e. another party takes on that role in relation to the vessel);
b) if there are new emission sources or fuels are used which are not yet referred to in the monitoring plan;
c) where there is a change in the availability of data (e.g. because new methods are being used to collect it);
d) where data resulting from previously used methods has been found to be incorrect; or
e) if the monitoring plan does not conform to the above requirements. (If the monitoring plan does not conform, the verifier will request that the company modifies the plan. In other circumstances, the company must notify any planned modifications to the verifiers without undue delay.)

Having chosen a method and prepared a monitoring plan, companies must then monitor emissions for each ship both on a per-voyage & annual basis (Article 8). Where emissions are monitored on a per-voyage basis, Article 9 stipulates that the following information must be monitored:
a) the ports of departure and arrival (including date and time of departure/arrival);
b) the total amount and emission factor for each type of fuel consumed;
c) CO2 emitted;
d) distance travelled;
e) time spent at sea;
f) cargo carried; and
g) transport work.

However, ships are exempted from the need to monitor emissions on a per-voyage basis if all the ship’s voyages either start or end at a port under the jurisdiction of a Member State or the shipper forms more than 300 voyages in a year.

Where emissions are monitored on an annual basis, for each ship the company must monitor:
a) the amount and emission factor for each type of fuel consumed in total;
b) the total aggregated CO2 emitted;
c) the aggregated CO2 emissions from all voyages:
–  between ports under a Member State’s jurisdiction,
–  which departed from ports under a Member State’s jurisdiction,
–  to ports under a Member State’s jurisdiction, and
d) any CO2 emissions which occurred at berth within ports under a Member State’s jurisdiction.
e) In addition, the total distance travelled, total time spent at sea, total transport work and average energy efficiency of the vessel must be monitored.

The schedule for implementation for EU-MRV
Reporting periods are defined as a calendar year. For voyages starting and ending in two different calendar years, the monitoring and reporting data is to be accounted under the first calendar year.
To simplify the preparation of monitoring plans and reporting requirements, electronic templates will be provided by the European Commission (EC). The following timescales have been set as part of the regulation:
Preparation and adoption of supporting technical legislation in 2015/2016 including broad stakeholder and expert involvement
– Accreditation of verifiers in 2017
– 31st August 2017 – Monitoring plan to be prepared and submitted for approval by an accredited verifier
– 1st January 2018 – Commence per-voyage and annual monitoring
– 2019 onwards – By 30th April each year, submit a verified emission report to the EC and relevant flag state
– 30th June 2019 onwards – Ships will need to carry a valid document of compliance relating to the relevant reporting period.
– 30th June each year – the EC will make each ship’s emissions reports publicly available including information specific to that ship, its fuel consumption, CO2 emissions, technical efficiency (EEDI or EIV as appropriate) along with other parameters.

Source: The Japan P&I Club and Lloyd’s Register