Aluminum Alloys in Fuel / Water Tanks

[knottybuoyz]

Anybody know off hand which Aluminum alloys are used in marine fuel/water tanks?

[Blue Stocking]

5052, I think

[noelex 77]

5083 and 5086 are best
5052 is is less strong than the above 2 alloys, but is often used for tanks and even hulls because it is cheaper.

[GordMay]

5052, 5083, & 5086 Aluminum are all listed for diesel fuel tanks.
Aluminum Alloy 5052
Aluminum Alloy 5083
Aluminum Alloy 5086

Potable water tanks are most often polyethylene, or 300 series stainless. I wouldn't recommend aluminum for water tankage.

[China Doll]

Posted in a new thread too:

Recommended Aluminum Alloy --Fuel Tanks
I am having a set of aluminum diesel fuel tanks built for which I spec'd to the fabricator to be built in Aluminum Alloy 5056 [~sorry, meant 5052] -H32, 1/4 thickness. The fabricator is apparently building the tanks out of what's labeled on the sheet aluminum as:

'ALUM LAM H 1100F'

I am not sure if this meets my original specifications as from what I have researched, this is basically a pure aluminum sheet that meets the 'F' specifications for hardness. The material is 6.045 mm thickness which is close to the 1/4 plate that I had asked for in my original specs.

Any ideas on the use of this aluminum alloy for marine diesel fuel tanks --these are fairly flat 50-gallon tanks with some bends and welds sized around 32 x 44 inches, max depth around 14 inches. The corrosion resistance is a main issue as the tanks sit in the bilge of the boat (on some narrow closed cell foam strips to keep them air dry) with some exposure to salt air, inside (fuel moisture contamination) and out.

I noted elsewhere that 1100F alloy is used in the manufacturing of tank cars (railroad?) --but I am not sure of this usage and the corrosion resistance and 'softness' of this mostly pure alloy. I had planned on painting the outside of the tanks with a vinyl wash etch (Interlux) followed by a two part epoxy harded paint (Interlux Bottom/Bilge-Kote).

Other notes on the sheet aluminum are as follows:

Casa Sommer SA
#ECO: 7337.0
#O.C.: 217714.0
#Pda: 1.000

6.045 1219x3048 [these are the product sheet size in mm as ~1/4 inch 4 feet x 10 feet sheet]

61.80 kg[?] / peso [feet?]