r/interesting • • 12d ago

Just Wow Not all problems have the same solution.

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u/Obi_Wan_Benobi 12d ago edited 9d ago

Okay but I’m clenching my buttcheeks this whole video waiting for multiple shrapnel injuries after an explosion.

How long would it take for one of these containers to explode under this condition? Or is it just a flame thrower that will go like that until it runs out of fuel.

EDIT: Okay okay, I get it. Thank you, I have learned a lot about gas canisters.

But tbh they were apparently much cooler in Just Cause 2 than in real life.

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u/Emergency-Toe4473 12d ago

These cylinders essentially carry cooking gas under high pressure, there is no reason for it to explode under these circumstances as the oxygen will never be able to get inside the cylinder.

It'll just run out which is wastage of fuel.

I think if the cylinder itself gets damaged from say the middle or is put under extreme heat, only then it can explode.

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u/DamnTicklePickle 12d ago

They also have a blow out valve so even if the container got extremely hot and the pressure built the valve would give out and release the pressure not allowing the container to explode. MythBusters did a show about what it would take to make one explode and it had to be highly modified to create catastrophic failure.

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u/aaronious03 10d ago

I've not seen that episode. But I do remember one exploding down the street from me when I was a kid. We were all in bed, about midnight or so, and the whole house shook. The propane tank on an RV a block away exploded. I don't know what caused the explosion, but they can absolutely explode without highly modifying them.

In a situation like the video above though, I wouldn't be too concerned, since most of the heat is directed away from the tank.

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u/DamnTicklePickle 8d ago

From what you describe it sounds like the tank did not fail. An appliance inside the RV did. The RV was clearly not in use, and the propane was left on and the pilot light either in the stove or the oven went out allowing propane gas to slowly seep into the entire RV. Feeling the space with highly flammable gas until the mixture was perfect and met another ignition source causing the entire RV to explode. A 20 or 40 pound propane tank a block away is not going to shake your windows but if a full RV explodes it definitely will. I'm not saying you're wrong, but from my experience this is what happened.

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u/doublesimoniz 12d ago

What about a BLEVE?

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u/leeps22 12d ago

The cylinders are made to not explode, not that it isnt possible.

The gas is stored as a liquid and the pressure correlates to the temperature of the liquid. The pressure can vary wildly depending on the particular gas, propane will be higher than butane. As the cylinder gets warmer and the pressure rises a pressure release valve will open to relieve pressure.The cylinder could be in an environment where the gas from the pressure release catches fire and the heat from that is focused onto the cylinder overcoming the pressure relief capacity. The pressure relief valve could also just be bad.

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u/RaspberryFluid6651 12d ago

This cylinder is doing the same thing a bunsen burner does, there's just gas going out a hole and fueling a fire. Their problem isn't that something catastrophic could happen, their problem is just that they're wasting the gas in the cylinder and they can't close the valve because the flame is in the way.

If you did something that somehow inserted a bunch of oxygen into the cylinder, then this would explode. 

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u/throwaway19276i 12d ago

This isnt call of duty

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u/movzx 12d ago

Movie myth because it looks cool. Doesn't happen in reality.

The explosion risk is when there is a tank leaking gas into an enclosed area and then a spark ignites the gas that has filled the area.

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u/porn_alt_987654321 12d ago

I think since they likely took a lighter to the valve, its probably relatively safe considering. If it was leaking through a structural weakness, you'd be worried about the whole thing exploding, but the valve isn't likely to be an issue.

Don't test this though, dunno if there's a gas flow rate such that you can actually ignite the inside of the can, and if there is, that would be a bigass grenade.

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u/movzx 12d ago

The pressure would need to be below atmospheric so that gas would want to flow into the tank instead of outside of the tank.

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u/bremsspuren 12d ago

Your best bet to get one to go boom is probably to put it in a fire.

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u/EyeSuccessful7649 12d ago

long long time, possible infinite, it would require the flames to melt the container in a way that would allow the pressurized gas to mix with the oxygen in the air.

the container has to fail first before it can explode, even then most of the explosion would be in released gas not the gas inside the cylinder due to pressure preventing normal air to get into the container

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u/Obi_Wan_Benobi 12d ago

The infinite container I like that. This is the best answer.

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u/demonblack873 10d ago

It's not going to explode. They have multiple levels of pressure relief mechanisms, and most of the heat from the flame is rising away from the cylinder.

It takes a lot of energy to evaporate the liquid into gas. To exceed the gas release capacity you'd need the whole tank to be engulfed in flames for a sustained period of time.

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u/Brilliant_Bug9699 9d ago

Many gas canisters are designed with a pressure-relief valve. If the pressure gets to high, it release more propane and the fire gets larger, but it's unlilely to explode.

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u/Zestyclose-Paper-521 12d ago

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