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File 140982088995.jpg - (141.67KB , 807x605 , 137518843779.jpg )
6434 No. 6434 ID: 9bee81
So I've heard that if you get grease lubricant on the valve of an oxygen gas tank(those big blue ones) it'll asplode? Is it true and if it is why does this happen?
Pic unrelated.
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>> No. 6435 ID: d444df
Yes it is very much true. The oxygen reduces the autoignition temperature of the oil/grease to below room temperature.

I'm sure someone who's more gooder at words than me can provide a much better explanation, but you have an answer.
>> No. 6436 ID: 1bcc0d
>>6434
It is much true, but I am too knuckle-dragger for know why.

It has something to do with the flammability of grease and oil in various mixes of gasses, and the fire-dampening effects of nitrogen compared to a mix of pure oxygen. Considering that fire is simply a rapid oxidation of various fuels, having pure oxygen in the presence of fuels with an already-low ignition temperature makes them much more likely to ignite than in a mix where the oxygen's only ~21%.
>> No. 6437 ID: 67f943
>>6434
The short form of it is that you end up making something called Oxyliquit.
https://en.wikipedia.org/wiki/Oxyliquit

Liquid oxygen is a scary good oxidizer, especially when mixed with hydrocarbons. As in, so good that if it spills, I'm running the other way, oxidizer.
There is a classic myth/story of a LOx truck spilling on a highway which then explodes, since the asphalt mixed with LOx made it explosive. Story or not, it has happened in smaller events; as mentioned in the article.
>"An oxyliquit explosive can be accidentally made by spilling liquid oxygen on tarmac during filling high-altitude airplane systems. The pavement then can become sufficiently explosive to be initiated by walking on it"
And that folks, is what I call one hell of a surprise.
>> No. 6439 ID: 7ba746
>>6437
>guy walks on pavement
>it explodes

That's so fucking metal.
>> No. 6440 ID: 264fa3
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6440
I don't know about lox specifically, but I know that if you use petroleum based lubricant on the valves of high pressure bottle, they kaboom.

The compression of the gas actually is several times that of a diesel cylinder, and will ignite the oil by itself, without a spark.

Oiling your regulators and valves is a big no-no in the paintball and scuba world.

It's one of the reasons I don't like buying used tanks.
>> No. 6442 ID: ebf03a
stupid question but why doesn't an oxy acetylene torch auto ignite then? does acetylene have too high of an auto ignition temp?
>> No. 6443 ID: fd2c08
>>6442
I'm not a fysics knowin' person, but I do know this.

Fire needs three things to exist. Fuel, oxygen, and heat. Compression can lower the amount of heat needed, but it still has to be there.


Oxygen tanks don't have fuel, acetylene tanks don't have oxygen, they mix in the touch head and do their thing there.

I don't know what would happen if you compressed an oxy-acetylene mixture, but I'm sure it wouldn't be good.
>> No. 6446 ID: b338a2
>>6437
New kind of IED?
>> No. 6447 ID: 67f943
>>6446

No, because just like water, the LOX will evaporate out over time; probably much faster than water would.
>> No. 6448 ID: 8f86b1
File 140999211415.jpg - (85.60KB , 1023x685 , 4vmvjo.jpg )
6448
OP, I just want to thank you for asking what could be considered a dumb question (sounds like a myth at first), because I had no idea and this is one of those things that seems pretty important to know, like not mixing bleach and ammonia.

I figure any day I learn a new way to not blow myself to fuck, is a good day.
>> No. 6449 ID: 9bee81
File 14100284576.jpg - (73.02KB , 363x529 , дети_всё_портят.jpg )
6449
>>6448
Well, I just remembered the story abut solid oil and oxygen tanks my granddad told me and thought that here would be the best place to ask.
Now I dunno if that really happened but this is what he told me.
My granddad was walking by an oxygen storehouse or whatever, place had tons of oxygen gas tanks and saw a bunch of kids dipping sticks in solid oil and throwing them over the fence at the gas tanks. I guess they knew about the possible reaction and wanted to see it. He told them to knock that shit off and went away. But after sometime he heard a huuuge explosion. The kids succeeded in their efforts but the explosion was so strong that apparently it set off the chain reaction with other tanks and the whole place just blew up.
>> No. 6451 ID: eaed30
>>6442
Acetylene tanks are actually filled with a very porous material and a bunch of acetone. The acetylene gas is basically dissolved in the acetone, and the combo of the acetone and the very, very tiny spaces and large surface area of the material keep the acetylene from spontaneously combusting.

There's a reason the gauge on the acetylene regulators has a big red stripe starting at around 15 PSI. If you run it much beyond that, the shit will go kaboom all on its own and it'll be a very bad day for you.

Neat fact: due to expansion, the oxy/acet mixture is actually pretty chill right up until it ignites at the tip of the torch. This is expected and actually part of the design -- it's what keeps the torch from overheating, and why you can actually run torches with too little gas and have problems.
>> No. 6497 ID: 5b2e73
>hook propane tank to oxygen tank
>open both, get the fuck outa there
So did I just "invent" the easiest, "safest", spark-free IED capable of intentionally a whole house?
>> No. 6498 ID: 6f677f
  Enjoy
>> No. 6555 ID: 604f11
File 141274456729.gif - (1.99MB , 300x232 , 1412743352584.gif )
6555
FLAME ON
>> No. 6556 ID: 8f9280
>>6555
dear god what is happening?
>> No. 6557 ID: 097fc9
>>6556
IIRC it was a natural gas station explosion in middle east
>> No. 6558 ID: f65b5f
>>6556
Hellmouth opening

This is why you run as hard as you can in the opposite direction when you see a rapid fire/explosion, even if it seems safe for the moment

Plenty of time to gawk later
>> No. 6559 ID: 9e61f9
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6559
>>6555
>a few minutes earlier

I'm gonna pull it. What's the worst thing that could happen?
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