Rotopax / Fuelpax expansion in the sun

[JaSAn]

Liquid expand less than the air so I overfill them.
If they expand allot when partially full I'll vent them off.

Liquid gas expands when hot but does not compress. So if overfilled, liquid gas will expand and compress the smaller volume of vapor to a higher pressure, beyond safe limits. Eventually something will give.
That is the reason manufacturers mold a 'do not fill above this line' on their plastic cans.

 

[Cabrito]

I have the opposite of some previous comments where my T-Handles are loose when I check them sometimes after I cranked them down pretty tight before leaving.

Wonder how much a cover / shading would do?

Good question. I've thought about that before. Sometimes I pack duffle bags on top of them. I'll need to do that again to see if it insulates them from the heat and sun.

My steel wavian cans are permanently deformed after one trip from St.Paul MN(600’and 30f) to Sante Fe NM (6000’? And 75).

The stream of gasoline when I stupidly opened the can up sprayed all over me and six foot over my shoulder.

It was actually pretty impressive.

This is interesting because I've had some Wavian, and Wedco 10L Nato type cans for years that never bulged or deformed. I was always impressed with them. I moved to the RotoPax due to the nozzles starting to leak and not being able to find gaskets for the nozzles (I can get gaskets for the lids, but they don't fit the nozzles)

 

[Buddha.]

I have the opposite of some previous comments where my T-Handles are loose when I check them sometimes after I cranked them down pretty tight before leaving.


Good question. I've thought about that before. Sometimes I pack duffle bags on top of them. I'll need to do that again to see if it insulates them from the heat and sun.




This is interesting because I've had some Wavian, and Wedco 10L Nato type cans for years that never bulged or deformed. I was always impressed with them. I moved to the RotoPax due to the nozzles starting to leak and not being able to find gaskets for the nozzles (I can get gaskets for the lids, but they don't fit the nozzles)

I bought them from British Atlantic? I think. They’re the green ones.
They’re deformed enough they don’t stand up straight anymore.

 

[Alloy]

Liquid gas expands when hot but does not compress. So if overfilled, liquid gas will expand and compress the smaller volume of vapor to a higher pressure, beyond safe limits. Eventually something will give.
That is the reason manufacturers mold a 'do not fill above this line' on their plastic cans.

From 60F to 100F the volume in an overfill 5gal tank will grow by 1/8-1/4 of a gallon. This is no where close to how much the tank expands when they are partially full. I've had sides of partially full tanks bulge at least 2".

 

[Regcabguy]

Metal Jerry-type cans aren't workable anymore? I used them in Baja for decades and never had an issue.

 

[krick3tt]

I have never used Rotopax. I cannot seem to justify the price when I have so many Nato cans and have been using them for many years. Can't seem to feel that a plastic container beats out a metal one. I can buy 4 Nato cans (I can source them for $20 military surplus) for the price of one Rotopax and they do not hold as much. I will put water in a plastic container (scepter can) made for water though.

I fabricated a holder for my RR to hold two Nato cans, it is lockable. I sewed a white canvas cover with an internal pocket to hold foil covered bubble insulation (the kind for water heaters) and it does manage to keep them cool enough that expansion is not a problem. In the desert I have had to vent them as the air reach an ambient temp far above what it was when I filled them.
The issue is mostly altitude change. I live at +5000 feet and going higher can be an issue.

I only open them with the fill hole facing away from me and cover it with a rag just for safety. That expanded gas (vapor or whatever) is really explosive under the correct conditions. It only has to happen once that you forgot to do this and you will never do it again.

 

[old .45]

I have never used Rotopax. I cannot seem to justify the price when I have so many Nato cans and have been using them for many years. Can't seem to feel that a plastic container beats out a metal one. I can buy 4 Nato cans (I can source them for $20 military surplus) for the price of one Rotopax and they do not hold as much. I will put water in a plastic container (scepter can) made for water though.

I fabricated a holder for my RR to hold two Nato cans, it is lockable. I sewed a white canvas cover with an internal pocket to hold foil covered bubble insulation (the kind for water heaters) and it does manage to keep them cool enough that expansion is not a problem. In the desert I have had to vent them as the air reach an ambient temp far above what it was when I filled them.
The issue is mostly altitude change. I live at +5000 feet and going higher can be an issue.

I only open them with the fill hole facing away from me and cover it with a rag just for safety. That expanded gas (vapor or whatever) is really explosive under the correct conditions. It only has to happen once that you forgot to do this and you will never do it again.

I Have always used NATO cans, winter, spring, summer and fall...... nary a problem ever!

 

[Alloy]

Liquid gas expands when hot but does not compress. So if overfilled, liquid gas will expand and compress the smaller volume of vapor to a higher pressure, beyond safe limits. Eventually something will give.
That is the reason manufacturers mold a 'do not fill above this line' on their plastic cans.

This was around 9:00 and just over 1/2 full.

It sat out in the sun the day before when it was full up to the edge of the fill spout and the sides only bulged out 1".


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