Best composite material for gasoline tank
Best composite material for gasoline tank
(OP)
Can someone comment on the properties of the following materials with regard to use as a gasoline tank? In each case, a choice of resin must be made. I've made a matix below to help simplify your responses (hopefully).
References or links appreciated, in addition to experience or guesses...please identify
---------------------- Polyester---- Vinylester----epoxy----
E-glass | EP | EV | EE |
S-glass | SP | SV | SE |
Aramid/Kevlar | AP | AV | AE |
Carbon fiber | CP | CV | CE |
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References or links appreciated, in addition to experience or guesses...please identify
---------------------- Polyester---- Vinylester----epoxy----
E-glass | EP | EV | EE |
S-glass | SP | SV | SE |
Aramid/Kevlar | AP | AV | AE |
Carbon fiber | CP | CV | CE |
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RE: Best composite material for gasoline tank
RE: Best composite material for gasoline tank
RE: Best composite material for gasoline tank
No bladder. Gasoline in direct contact with the composite surface. That is the thrust of my question. My understanding is that one of the reinforcment materials I listed tends to soak up fluids more than the others, but I can't remember which one! CRS.
RE: Best composite material for gasoline tank
RE: Best composite material for gasoline tank
That said, I would be very curious if there are any recommended coatings/alternative resins which might provide a longer service life
RE: Best composite material for gasoline tank
Oh, I just dug this up: http://www
It's a primer used on the composite fuel tanks for 787.
RE: Best composite material for gasoline tank
Do not forget that you will also need a means of discharging static build up from fuel filling the tank.
i.e copper tapes or mesh.
B.E.
RE: Best composite material for gasoline tank
Interesting. I see motorcycle fuel tanks advertised that seem to be fiberglass, kevlar or carbon fiber, sometimes in combination. No mention of resin breakdown issues in their sales literature (no surprise I guess).
Here's a quote from one such website:
"Q. Do your tanks require a bladder and or do I have to apply a fuel proof coating on the inside such "Kreem"?
A. Neither. FuelCels are inherently fuel proof and leak free by creating an impervious shell matrix. In fact, a coating would have nothing to stick to and could peel off and get into your fuel system."
... and from the same site-
"Q. Will I have to drain my race fuel from my tank?
A. The epoxy matrix we use has never exhibited any problems with race fuels over extended periods of time."
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Berkshire,
Thanks, I would not have thought about this until the first (and last?) discharge!
RE: Best composite material for gasoline tank
There are a great many glass/polyester and glass/vinyl ester pressure vessels out there with a big variety of corrosive fluids and solvents in them. Glass/epoxy is also sometimes used, but epoxy's superior properties are generally not worth its extra cost in this sort of application. (For most applications, epoxy isn't that much better than vinyl ester anyway.) The same applies to carbon fiber; it's really only used for weight-critical pressure vessels. S-glass is strong, but there's probably little reason to use it here. I would avoid Kevlar or other organic fibres in this context. Kevlar doesn't stick that well to polymer matrixes to start with, and having solvent around can't make things any better.
For all common matrixes I would not anticipate a great problem with gasoline, though orthophthalic polyester should not be used. The matrix near the wetted surface will be slightly plasticized, giving a slight reduction in compressive properties. You could use a liner to avoid this, but there is no great necessity. If the external surface is exposed to the elements it should be painted to have good durability (many years).