Oil combustion is essential to generate energy on ships regardless of propulsion system types. Massive fuel is used on ships for daily power generation for ship propulsion. Therefore, necessary fuel oil amount storage is essential for voyages.
A bunker is simply the fuel oil, fresh water, and lube oil for the use of the engine and ship. However, the word bunkering represents the process of receiving and transfer of bunkers into tanks for the own consumption of ships. Some still call it the oil transfer process for the consumption of ships. At the same time, the tanks used to transfer this fuel oil are called bunker ships.
Understand the basics of Bunkering: All you need to know about
Before stepping onto the bunker checklist, it is imperative to understand some basics of bunkering to understand this regard better. So, here we go:
Types of bunkering
Previously, bunkering was done on the ports only. However, modern techniques have made it possible to bunker at sea in normal weather conditions. The most widely used bunkering technique at sea is STS bunkering, which means ship-to-ship bunkering. In this type of bunkering, one ship will perform as a terminal while the other acts as a moor.
Stern line bunkering is another key bunkering type here. Even though stern line bunkering is considered the easiest bunkering technique, it can be a riskier way to transfer fuel because of bad weather at sea.
Key bunker fuel oil types
Here are the principal fuel oil types of bunkers you should know:
Residual fuel is a mix of distillates and residual fuel blended for certain requirements. This fuel oil type has two viscosities, both low and high Sulphur.
Distillate fuel is gotten from the condensed vaporous distilled by crude oil of petroleum. It comes in two variants, both low and high Sulphur.
Marine Gas Oil doesn’t possess any residual components. At the same time, Marine Diesel Oil may contain residual components in a small amount.
Preparation of bunker plan
A chief engineer will make the bunkering plan before discussing it with anyone involved. This plan usually covers different bunkering aspects, including the number of tanks required, tanks filling sequence, bunkering process, topping-up procedures, transfer rate, different types of oil tanks, fuel oil overflow conditions, etc.
A typical bunkering plan usually includes the following:
- Grades to be transferred
- Emergency procedures
- Stress and stability conditions
- Responsibility for bunkering operations
- Loading sequence
- Checking before, during, and completion of the process.
The shipping company then approves the bunker plan before heading with it. To understand the bunker checklist, we will divide this process into 3 different steps. These include before, during, and after bunkering.
So, here we go:
Bunker checklist: Before
Creating a before-bunker checklist is the most important bunkering operation stage. It typically involves ROB calculation, bunker ordering, bunkering checklist, bunker plan, paperwork, SOPEP, preparation, and communication. During this stage, all overflow tanks and bunker tanks soundings are taken. Engineers also calculate ROB and necessary bunker for the upcoming voyage.
The checklist at this step will include the following:
- Warning and notice for bunkering
- Red light or flag’s presence for bunkering operations
- The placement of SOPEP items near manifold
- Availability of portable fire extinguisher
- The setting of valves and pipelines for bunkering
- Inspection and sounding of barge or truck of bunker supplier
- Specifications and compatibility of the bunker are checked.
The team will ensure that the pre-bunker checklist is properly checked before moving to the next step. Seeing weather conditions, matching of products from a supplier, proper security of ship to dock, checking open valves, Ready SOPEP plan, responsible communication, emergency shutdown process, meter reading of ship, etc. are also a part of the pre-bunkering checklist.
Bunker checklist: During
So, here is the second bunkering stage that includes actual bunkering such as bunker tanks filling and refueling ship. It is better to keep a minimum pumping rate to initially ensure the oil transfer into the right tanks without any problem. However, you can gradually increase the pumping rate to the max when the proper transfer is confirmed.
The sequence of transferring oil in bunker tanks should be according to the plan. Moreover, it is imperative to fill all the tanks simultaneously to avoid fuel overflow. It is always better to fill oil tanks to 90% only. Always ensure to check the relief valve and overflow tank sounding regularly.
The checklist will cover the following aspects of bunkering:
- Proper sealing and sampling
- Monitoring hose connections
- Bunker tanks’ changeover
- Barge and trucks of suppliers are secured tightly
- List and trim of barge and ship of supplier
Bunker checklist: After
So, here is the final step of bunkering, which includes multiple steps. These are the bunker's disconnection from the hose of the supplier, paperwork, sampling, received bunker calculation, and its analysis. It is simply the closing part of the entire bunkering process. It is necessary to avoid quickly shutting the valves or openings after the bunkering operation’s completion. Instead, it is better to wait for a while for air removal. Then shut all the valves and openings.
You should also check the ship's draft or trim and bunker barge. This practice will ensure that the received bunker is completed according to the temperature and draft. In case of bunker shortage, you can issue the LOP (Letter of Protest).
Fill the sample bottles with the sample oil gathered in the cubitainer. You can remove the hose connection after completing the bunker calculation and paperwork. If there is any dispute regarding the quality or quantity of the bunker, then the chief engineer can issue LOP.
The last step in the process is to fill the oil record book.
However, the checklist after bunkering will include the following:
- Closing bunker valves
- Draining manifold connection of bunker
- Disconnecting hose
- Supplier’s flow meter reading
- Ship’s flow meter reading
- Delivery notes for bunker
- Collection of sampling
- Keeping SOPEP items back in the SOPEP locker
- Removing portable fire extinguisher
- Oil record book filling
- Informed bridge
Safety is of the utmost importance throughout the bunkering process. The actual reason to create a bunker checklist is also to ensure safety. The bunker operation is arguably risky and contains fire risk, air pollution, oil pollution, loss of life, money, and even loss of machinery also. Therefore, it is important to consider the bunker checklist throughout the process for ensured safety.
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