Oceangoing Cargo Ships Safety & Operational Matters
Home || Tanker Safety || Container Ship Handling || Commercial Management || EMS ||

Attention to Acceptance or Rejection of Fuel Oil - Cargo ships Bunkering procedure

Due to its low cost, most large cargo vessels are powered by bunker fuel, also known as Heavy Fuel Oil, which contains higher sulfur levels than diesel. The fuel oil releases energy to rotate the ship propeller or the alternator by burning fuel inside the engine's combustion chamber. It also helps to generate steam inside the boiler.

Accepting fuel oil for ship use needs some careful consideration since poor quality fuel can cause ships main engine fuel system operational problems, such as purifier or filter clogging, fuel pump scoring or failure, severe cylinder liner wear, fuel injector seizure, exhaust valve seat corrosion or blow-past and turbocharger turbine wheel is fouling. Above is just a shortlist of potential problems. Ships chief engineer should apply his best judgment before deciding to accept or reject bunker fuel oil. The following guideline might be useful in this respect.



containerships operational matters
Oil Tanker Safety Guide
Difference in viscosity:
  1. If the deviation falls within the range allowed by the vessel side, the FO may be accepted in principle.
    Note: The allowable range for viscosity shall be, talking the machinery specifications, heating specifications, and specifications of auxiliary machinery that burns C-oil only talking into consideration; an upper limit of 200 CST or so to 180 CST in the machinery specifications, an upper limit of 300 CST or so to 280 CST in the machinery specifications, an upper limit of 450 CST or so to 380 CST in the machinery specifications.

  2. If the deviation is out of the range allowed by the vessel, the Chief Engineer shall refuse the receiving in principle, and shall make the supplier rearrange the type of Fuel to meet the order, if time permits. In this case, the time required for the re-arrangement and the following FO loading shall be confirmed after consultation with the local agent.

  3. If there are significant differences in viscosity, Chief Engineer needs to consult with the shipowner Fuel Section immediately. A decision to accept can only be made after receiving approval. A suitable letter of protest to be issued to the bunker supplier. It will be helpful resolving dispute.

Difference in Sulphur content
  1. The chief engineer should be meticulous regarding Sulphur content in a Bunker Delivery Note. IMO global sulfur limit of 0.5% should be strictly complied with in all cases. Any non-compliance, the Chief engineer should refuse to load and request re-arrangement.

  2. In the above case, the Chief Engineer shall inform the Fuel Section of the matter through the Master without delay and discuss whether the FO in question is to be received or not.

Excessive density

The upper limit of density should fall at 0.9910kg/m 3 at 150C(0.9916kg/m 3 at 60F), (according to ISO Standard). Therefore, if it is discovered by the confirmation made on the document before the loading that the density exceeds the upper limit, the Chief Engineer shall postpone the receiving and report the fact immediately to the shipowner Fuel Section and the Chief Technical Superintendent. A final decision can only be taken after receiving instructions.

For rules and standard on qualities of marine fuel oil, refer to the attached Specifications of Marine Fuels, ISO 8217, 1987(E) .

Excess or shortage in volume

If it is discovered by the confirmation made on the document before the loading that the loaded volume exceeds the ordered volume, the Chief Engineer shall refuse to receive the excess. In this case, the Chief Engineer should have the supplier accept that the vessel side shall make the judgment of the timing and the order to stop the pump after the loading of the planned volume, which an agreement shall confirm procedures in writing between the parties.

Furthermore, if it is discovered by the confirmation made on the document before the loading that the loaded volume is less than the ordered volume, the Chief Engineer should take the following measures:
  1. The Chief Engineer shall make the supplier rearrange the deficiency immediately if time permits. In this case, the time required for the re-arrangement and the following FO loading shall be confirmed after consultation with the local agent.
  2. Re-arrangement of deficiency may not be possible if there is not enough time. However, if the total remained fuel oil onboard is sufficient for safe navigation of vessel until the next port where refueling is possible such bunkering may be accepted in principle. In such case, the ordered volume shall be entered in remarks column on the bunker receipt, and the Chief Engineer should discuss with the owner where the deficiency is supplied or whether the supply is required or not, without delay.
    The chief engineer should judge the total volume of remained FO on board the vessel, and the newly loaded FO to the safe navigation of the vessel to another port where refueling possible. If a deficiency is found in newly loaded fuel oil, there is no time to rearrange the deficiency, and ships total ROB insufficient to reach the next bunker port, the chief engineer should report immediately through the Master the situation to the owner to seek further guidance.

In such a case, the Chief Engineer should include in the report information about the expected delay of the vessel on possible re-arrangement of the following refueling. Local agents and bunker suppliers should be in coordination to minimize the delay.

Determining H2S

All cargo vessel types need to have sufficient measuring instrumentation onboard. It was found H2S is most accurately measured using Draeger tubes (Type 2a). Draeger tubes are less prone to inaccurate readings due to cross sensitivities with other substances than electronic meters. A vessel with ten tanks or more may use a large number of tubes if testing two, three or more times.

It is now common to have a standard H2S Clause in a charter party fixture. The penalties for breach of Terminal regulations and C/P Terms are severe, both financially and commercially.

For guidance the Shell H2S Clause as follows:
Quote

Unquote

In addition INTERTANKO note on H2S as follows:

While the dangers relating to Hydrogen Sulphide (H2S) are not new, there is a a growing body of evidence suggesting that H2S levels in some crude oils are on the increase. The reason for this apparent increase is unclear. H2S is known to be present in crude oil exported from several countries including Iran, Qatar, South America, Mexico, Poland, Latvia, Russia, and Turkey. Recently higher than normal amounts have been detected in Brent crude and within the last few days very significant amounts of H2S have been found in the ullage spaces of two tankers loading fuel oil cargo at Jubail in the Arabian Gulf.

Terminal operators should remain alert to the dangers posed by the presence of H2S, either within cargoes being delivered or remaining within the residues from a previous cargo. The precautions and procedures described within ISGOTT should be strictly adhered to.

The advent of Inert Gas and Closed Loading systems has largely negated the need to open tanks except for non-routine purposes, although reducing tank pressures to near zero for sampling is a relatively common practice. Purging for cargo preparation is also common, thus the planned release of the entire tank atmosphere, particularly where unexpectedly high levels of H2S are involved, poses a significant danger to individuals in the immediate and, in some cases, the not so immediate area. Some countries, particularly in Europe, have already stipulated maximum H2S levels in tanks before loading and some terminal operators have reduced their acceptable arrival levels from 10ppm to 5ppm.




Related articles

  1. Acceptance / rejection of fuel in a quality dispute
    Accepting fuel oil for ship use needs some careful consideration since poor quality fuel can cause ships main engine fuel system operational problems, such as purifier or filter clogging, fuel pump scoring or failure, severe cylinder liner wear, fuel injector seizure, exhaust valve seat corrosion or blow-past and turbocharger turbine wheel is fouling. Above is just a shortlist of potential problems. Ships chief engineer should apply his best judgment before deciding to accept or reject bunker fuel oil......


  2. Operational guideline during bunkering
    Fuel oil bunkering is a critical operation onboard ships that require receiving oil safely into the fuel oil tanks, without causing an overflow of oil. With the cost of bunkers amounting to 50% of the total operating costs of ships, shipowners need to seek ways to monitor and control this vast expenditure continually. Typically, physical custody transfer of bunkers is made thousands of miles away from the contracting parties' offices, with neither buyer nor seller present during actual bunkering operations. ......


  3. Common bunker terms and related guideline
    Ships bunkering is generally applied to the storage of petroleum products in designated tanks for ship's main engine propulsion and power generation at sea. Bunkering is a major voyage cost for ship owners to run their business. A prudent shipowner/operator needs a bunkering plan – allowing for the purchase of bunkers at the best price in quantities sufficient for a safe voyage, but also allowing for the maximum carriage of cargo. Refueling of ships is carried out at all major seaports. ........


  4. Ships bunkering guideline- planning, preparation, safety checks & confirmation
    Bunkering checklists should be implemented to reduce the risk of negligence and other operational errors. They must be followed in consultation with the chief engineer, as he is normally the designated officer-in-charge of the bunkering operation. Before bunkering, usually, a junior engineering officer takes soundings of bunker tanks and calculates the volume of fuel oil available in every fuel oil tank on the ship. Then a bunker plan is prepared for the distribution of the fuel oil to be received.


  5. Bunkering arrangement and safety factors onboard
    When disputes arise over quantity and quality transferred, investigations after delivery are usually inconclusive if the shipboard personnel of the receiving vessel is not correct and or fully informed and trained. Protests, legal fees, management time, loss of goodwill, stress all add on to costs with usually neither party concluding with certainty what transpired onboard......


  6. Bunkering safe procedure and detail guideline for ships
    Bunkering may take place offshore, at anchor or alongside. It may be pumped from a road tanker, bunker barge, or another tanker or ship. Whatever the provider, the procedures followed are similar. Bunkering should be considered a high-risk operation, where mistakes can result in pollution, high financial penalties, or even imprisonment......


  7. How to keep bunkering record ?
    The consequences of bunker shortage or off-specification bunkers can be very severe. A lower quality bunker supply can lead to ship engine failure, incur loss-time, and additional expenses for refueling. In many parts of the world, greedy bunker suppliers make tricks to supply less. Both this situation not only increases the financial burden of a shipowner but also damages business reputation. Some critical considerations, therefore, need to be made for a safe bunkering operation.


  8. Precautions prior transferring fuel oil into storage tanks
    Fuel oils are loaded through deck fill connections that have sample connections provided to allow the fuel to be sampled as it is taken aboard. HFO is placed in storage tanks fitted with heating coils. In preparation for use, HFO is transferred to the fuel oil settling tanks via FO transfer pumps, which are equipped with a suction strainer. Piping is so arranged that the pumps can convey fuel between storage tanks and the deck connections for offloading. Settling tanks are used to sanction gross water and solids to settle on the bottom. ......


  9. Treatment of waste oil and oily bilge
    All modern cargo ship types are now essentially equipped with incinerators to process waste oil, bilge, and sludge generated in ships' machinery spaces and also overboard discharge arrangements under 15 ppm. However, if such onboard disposal is improper or impossible especially when ship transiting through a special area, all waste items should be taken ashore for disposal at a shore receiving facility......


  10. Procedure for oil tankers and how to maintain records
    Tankers are specialized vessels that include crude oil, product, chemical, LNG, and other tanker types. Tankers spend considerable time in ballast given the typical one -way nature of the underlying trades. Tankers are selfdischarging and most are equipped with a series of pumps that allow for a fast turnaround in port......


  11. Heating of fuel oil storage tank
    Ships fuel oil bunker tanks and waste oil tanks must have some form of tank heating. Normally the heating is by way of steam produced by an oil-fired boiler and passed through coils inside the oil tank. Other ways to heat the fuel tanks are by using thermal oil. It also utilizes an oil fired boiler that heats the thermal oil, which is circulated through coils inside the tank by a pump. Temperature regulation and monitoring can be automatic and self-adjusting but are commonly effected by checking the tank temperature and manually adjusting the heating accordingly......


  12. Fuel oil viscosity control
    Fuel viscosity control is a method to control viscosity and temperature of Fuel Oil (FO) for an active fire in diesel engines of motor vessels and generators of oil-fired energy plants. Fuel oil's viscosity heavily depends on the temperature; the higher is the temperature, the lower is the viscosity......


  13. Tanker vessel safety guideline - inert gas system
    Vessels carrying cargos that produce hydrocarbon vapors require an inerting solution to eliminate the risk of explosions and fires in cargo tanks ( crude oil tankers, chemical tankers, product tankers, gas carrier, etc.). Inert Gas System is used to keep the oxygen content below 8%, a standard set by the International Maritime Organisation ( IMO )......


  14. Tanker vessel safety guideline - gas freeing procedure
    The safest way to gas free an oil tank which is fitted with an inert gas system is to use a fan and vent the tank. Before entry, an O2 meter must be used and the tank must also be checked with an explosimeter. These meters must also be used while in the tank. The sketch shows a diagrammatic view of an explosimeter.....


  15. Precautions prior entering freezing zone - Check items in oil tankers operation
    Ocean water freezes just like freshwater, but at lower temperatures. Freshwater freezes at 32 degrees Fahrenheit, but seawater freezes at about 28.4 degrees Fahrenheit, because of the salt in it. Due to the presence of many hostile conditions, any merchant ship, while entering a freezing sea area, significant challenges are being encountered concerning safety and reliability of navigation. Shipmaster should ensure that the following measures have been taken to prevent damage to Vessel, Machinery, Pipelines, and Equipment prior entry into areas with Freezing Conditions......


  16. Tanker vessel safety guideline - how to prevent oil spillage
    There exists an inherent risk of oil spillage while handling oil cargo on board an oil tanker. However, good prevention initiatives can go a long way in reducing the risk of oil pollution from ships. In the event of any oil spillage from the ship, it is necessary to ensure that effective preparedness measures are in place to ensure a timely and coordinated response to limit the adverse consequences of pollution incidents involving oil and hazardous and noxious substances (HNS). We have summarized below some fundamental guideline for safe handling of oil cargo.....


  17. Tanker vessel safety guideline - tank cleaning procedures
    Tank cleaning is the process of removing hydrocarbon vapors, liquids, or residues from cargo tanks onboard a tanker. Tank cleaning may be required for one or more of the following reasons: To carry clean ballast, gas-free tanks for internal inspections, repairs, or before entering the dry dock. Also to remove sediments from tank top plating.


  18. Pumproom procedure
    A pump room onboard an oil tanker contains the largest concentration of cargo pipelines of any space within the ship and leakage of a volatile product from any part of this system could lead to the rapid generation of a flammable or toxic atmosphere......


  19. Pumproom inspection for tankers
    Correct use and setup of pump room(s) ventilation systems are essential to ensure that pump room(s) remain free from explosive or toxic atmospheres. Invariably the system fans are set up to make suction from below the bottom floor plates, i.e., from the bilge area. It gives full and proper circulation of all air in the pumproom to maintain a safe atmosphere......


  20. Crude oil washing for tankers
    Crude oil washing (C.O.W.) is a system whereby oil tanks on a tanker are cleaned out between voyages not with water, but with crude oil - the cargo itself. The solvent action of crude oil makes the cleaning process far more effective than when water is used. However, such a technique of washing cargo tanks involves many hazards, and careful consideration will need to be made for safe planning and execution. ......


  21. Oil pollution prevention method
    Any misuse of fuel oil can lead to significant claims and jeopardize the safety of the ship. The International Safety Guide for Oil Tankers and Terminals (ISGOTT) makes recommendations for the safe carriage and handling of petroleum cargo, which is seen as a fundamental part of overall Tanker Safety.


  22. General precautions for tankers
    Navigating through thunderstorms should be avoided as far as practically possible by changing of course while cargo related activities are carried out which may result in discharge of flammable vapors. If the passing through thunderstorms cannot be avoided, all open cargo oil tank hatches should be closed until the vessel has passed through the thunderstorm The valves in the main vent lines may be temporarily secured in locked position, but must be opened immediately after passing through the thunderstorm........


  23. Tanker equipment and machinery
    The Chief Engineer and Chief Officer shall jointly be responsible for the inspection and maintenance of the following cargo oil transfer equipment and machinery before entering port. The Chief Engineer shall prepare and maintain the equipment manuals of machinery and equipment, including critical components related to cargo operations including the procedures for their Emergency operation. All items should be in good operational condition.


  24. How to ensure safe working atmosphere onboard?
    ShipBoard Safety Checklist- Safety & House Keeping Checklist....




Other info pages !

Ships Charterparties Related terms & guideline
Stevedores injury How to prevent injury onboard
Environmental issues How to prevent marine pollution
Cargo & Ballast Handling Safety Guideline
Safety in engine room Standard procedures




ShipsBusiness.com is merely an informational site about various aspects of ships operation,maintenance procedure, prevention of pollution and many safety guideline. The procedures explained here are only indicative, not exhaustive in nature and one must always be guided by practices of good seamanship.

User feedback is important to update our database. For any comment or suggestions please Contact us
Site Use and Privacy - Read our privacy policy and site use information.
Terms and conditions of use

Copyright © www.shipsbusiness.com All rights reserved.