Fuel Systems Flashcards
(28 cards)
What are the 5 ways of embarking fuel?
RAS Road bowser/tanker Jetty storage tanks Lighter barge Fixed jetty pipeline
What is the purpose of the filling trunk and manifold?
To even out the pressure of the fuel when embarking.
What is a displacement tank?
A fuel tank that will contain sea water. It holds fuel for storage and acts as a ballast for ships stability.
To what level can displacement tanks be filled while at sea and why?
90% capacity to reduce the risk of fuel being discharged into the sea and allow for expansion due to temperate change.
Why are displacement tanks divided up?
To avoid splash due to the movement of the ship.
What is an un-dispaced tank?
Tank that does not contain sea water and only holds fuel (could be dirty fuel).
What is the purpose of the centrifuge?
It separates fuel from water using centrifugal force. One clean, the fuel is then stored in a service tank ready for use.
To what level should un-displaced tanks be filled?
95%
What is the purpose of the transfer pump?
It transfers fuel from the un-displaced tanks to the machinery space service tanks.
What is a coalescer?
Water separator for any final water droplets that may still be in the fuel.
How does fuel get from the displacement tanks to the un-displaced tanks?
Via the centrifuge, it cleans the fuel and acts as a pump.
What is the purpose of the fuel tank filling valves?
To isolate the manifold from the displacement tanks.
What level do the pre filters filter the fuel to?
5 microns
What is the ring main?
A machinery space fuel supply system delivering fuel to individual ready use tanks and main gas turbines.
What is MBG and where would it generally be found?
Micro biological growth. Found in virtually all fuels, especially when there is water in the tank. Most likely to be found in the interface.
What is the purpose of the salt water gravity tank?
To supply the displacement tanks with sea water as fuel is removed. The gravity tank is higher than the displacement tanks, giving a head of pressure.
What does the emergency run down valve do?
Allows a gravity fuel supply to gas turbines should the boost pressure be lost.
What 4 tests are carried out on diesel?
Visual test
Water reaction test
Colour test
Diesel fuel filtration test kit
What level does a coalescer filter fuel to?
10 ppm
Explain visual test.
Fuel should appear clear and bright at all times.
Explain water reaction test.
Carried out at embarkation. 20ml distilled water and 80ml fuel left to settle. Must be no more than a 2ml interface (cloudy area).
Explain colour test.
Gives an indication of fuel age. Darker is older. Lovibond colour comparitor test.
Explain diesel filtration test kit.
Gives an indication of how quickly filters will block. 250ml of fuel must pass before pressure reaches 15PSi
What 3 things are fuel tested for?
Water
Dirt
Surfactants
