Tanks Flashcards
4 types of JP5 storage tanks
- Wing tanks
- deep- centerline tanks
- double bottom tanks
- peak tanks
Wings tanks
Deep tanks located in a FWD and AFT row along the hull on the port and STBD side of the ship.
- normally 2 rows of wing tanks on each side of ship.
- top of the tank is the 4th deck and bottom is shell of the ship.
- each port tanks has an identical tank but on STBD side of ship.
- the twin tanks are filled as one unit to preserve lost and trim of ship
Deep-center line tanks
Originally for AVGAS but converted to JP5.
Double bottom tanks
Has a bottom and an inner bottom .
- top of double bottom is the deck of the bilge.
- bottom of double bottom tank is the shell of the ship .
- they are shallow tanks
Peak tanks
- deep tanks that are located in the extreme bow and stern of the ship below the waterline
- only the bow is used for JP5 presently.
TLI’s used are marked with what
The tanks number
Sounding caps are what kind of fitting
X-ray fittings and must be closed after each use
Wing and deep center line tanks are used for ?
Service tanks
Storage tanks and piping inside the tanks are sandblasted and coated with
A protective coating to minimize rust formations
Air escape riser does what ?
Vents the tank to the atmosphere
Air escape vent line extends where
Extends from the top of tank to an air escape main that runs FWD and AFT just below the main deck .
What is the purpose of the Air escape riser ?
Prevents a build up of pressure when tanks are being filled .
- prevents a vacuum from forming when tank is being emptied.
The air escape piping penetrates the skin of the ship and into where ?
The open atmosphere
The air escape screen is how many mesh?
60-mesh
Overflow lines extends where ?
Top of the storage tank to the over flow tanks
Overflow line is larger why?
To prevent rupture of storage tank in the event of overflowing at high pressure.
What is on the overflow line that prevents back flow into storage tank
One - way check valve
Bolted man hole cover on the tanks is for what?
Inspection, cleaning, maintenance
Sounding tubes extend from the extreme bottom of tank to where ?
2nd of 3rd deck
The lower end of sounding pipe has what?
Striker plate
And the upper end has what?
A mounted TLI
Sounding tubes have evenly spaced holes for what?
To ensure that the level of the fuel in the tube is the same level in the tank
The bottom of tube has also a takedown joint that is for?
Retrieving sounding bobs or tapes that brake inside sounding tube
Suction and fill pipes extend from the manifold to how far off the the bottom of tank?
6-24” inches
What is installed at the end of the suction and fill tailpipes?
A non vortex bell mouth fitting and a splash plate.
What is the purpose of the non vortex bell mouth fitting ?
- Reduces turbulence when filling
- prevents a vortex when emptying tanks
- prevents taking suction directly off the bottom
The stripping tailpipe is similar in design as suction and fill tailpipe except ?
It is smaller and has no splash plate
How far does the stripping tailpipe extend from the manifold to the bottom of tank?
1 1/2” off bottom of tank .
When consolidating JP5 fuel, the stripping tailpipe removes the last how many inches of fuel?
24”
Overflow tanks have the same design as the other storage tanks with the exception of ?
The overflow line and the arrangement of vent line
The overflow tank go where once overflowed?
Overboard .
The overflow tank have a check valve to prevent what?
Prevent sea water from entering tanks
What kind of valve in the overflow line
Spring tensioned wafer valve
Contaminated tanks are designed for
JP5 fuel from hose flushing , defuel, tank stripping operations, and the initial flow when fueling at sea
Each defuel piping that go into contaminated tanks branch how far from bottom of tank?
About 48 inches from bottom with a 24” horizontal run to reduce turbulence
Fuel in contaminated tanks will be filtered through? Then into stowage tanks
- prefilter/reclaim
What kind of valve on the overflow line?
Spring tensioned wafer valve
When are contam and purifier sumo tanks cleaned ?
Every 18-21 months
When are the storage tanks cleaned ?
Every 36-39 months
When are the storage tanks cleaned ?
Every 60-63 months
