7.7 Fuel Oil - 7.7 Fuel Oil Flashcards
Types of fuel
Turbine Jet Fuels: F-44 (JP-5) Kerosene
Middle Distillate Fuels: F-76 (DFM)
Fuel Characteristics
Storage Stability
Color
Appearance (clear and bright)
Flash Point
Viscosity
Reasons for Fuel Testing
To establish the level of contamination
To ensure that the fuel can be stored safely
To establish the density of the fuel for weight distribution and heating value
When do we Fuel Test?
Conducted during the receipt of fuel, taken at the refueling station
Prior and during transfer from storage to service tanks
Prior and during use from service tanks to engines
API/Specific Gravity test
(American Petroleum Institute) test is the weight of given volume of fuel vs. weight of an equal volume of water at 60°F
Flashpoint Test
Completed during fueling operations
Fuel is heated in a closed cup at a specified rate until a flash is detected either visibly or by sensing pressure build-up
Bottom Sediment and Water Test (BS&W)
Done during receipt of fuel and periodically as needed
Conducted by the Oil King in the Fuel Lab for amount of contamination
Two fuel samples are placed in a centrifuge
Sample is UNSAT if the sample contains contamination of:
-0.1% Shipboard or Navy supplier
-0.05% Non-DOD/NATO Source
Clear and Bright Test
Most common test
Clear = absence of visible particulate matter
Bright = absence of visible suspended water
Fuel System Overview
- Fuel is taken onboard via receiving station(s)
1.-2. Upon delivery fuel is routed to the Storage Tanks
2.-3. When fuel is needed, the transfer system will be used to transfer fuel from Storage Tanks to Service Tanks
The transfer system purifies the fuel slightly
3.-4. Fuel is then supplied to the engines via the Service System
Service System further purifies fuel ready for use in the engines
Fuel Oil Storage System
Series of banks filled from the header from the refueling stations
Sea water compensated fuel storage tanks are always completely full of liquid
Tank Level Indicators (TLI) are floats that provide electrical signals to Fuel System Control Console (FSCC) to indicate level
-Primary cause of system failure
-High SW: 90%
-Fuel overflow: 95%
F/O Transfer System
Transfer from the storage system
F/O Transfer Pump
F/O Transfer Heater
F/O Purifier
F/O Purifier
Is a belt driven, centrifugal pump that separates according to specific matter
-Separates into fuel, water, and solids
-If F/O Purifier drain tank exceeds 95%, transfer pump will secure
F/O Transfer Heater
Heats fuel to bring it to optimum temperature for purification
-Temperature regulation valve controls temp to 100 deg F
F/O Transfer pump
Rated at 135 gpm at 50 psi
Internal relief valve relieves at 60 psi
F/O Service System
Service tanks are filled from the F/O fill and transfer system through a fill connection and then supply fuel to the F/O service system through suction connections
