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heres a gas pressure vessel can i get some advice.
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SeanB:
I had the training on LOX and high pressure oxygen, and even things like having shoes with polish on them can be flammable. We had a special dispensation not to polish our working shoes, because of the risk of the wax catching fire. In the military, where shoe polishing is considered an art, and your shoes are expected to be a mirror like gloss at all times, but us Instrument fitters were exempt. We did have fun with that rule.

But remember that oxygen, even at 1 atmosphere, is very much going to support combustion, even for things they you would not consider flammable, like paints, most plastics (including PTFE, even if half the oxygen equipment uses it for seals and piping), aluminium, once the oxide layer is breached, and even stainless steel. Put it under pressure and many more things will burn, such as that little burr scraped off the surface when putting the lid on, and definitely any cheap unknown seal material used in the lid, likely some form of silicone rubber or EPDM or nitrile rubber, it will likely either smoulder or simply burn, and once there is a hole through the gas flow will turn the burning material into a flame jet.

We had separate armoured rooms where the oxygen equipment was kept, with blast proof doors, and with clear access so that the blast would not damage much more than the room. Inside the lighting was all heavily armoured, liquid tight IP68 rated Pratley EEX rated boxes, lamp enclosures, and with the power switch outside the room. The filling of high pressure cylinders was an entirely separate section, with a prefab hut for the operation, so the blast would not be fatal for too many other than those inside, and the cylinders were always filled with no people in the room, and all outside by the vapouriser, behind it's own blast wall.

Pure oxidiser gases are dangerous. Oxygen, flourine, chlorine and bromine, because they all support vigorous combustion and are common, and either gas or liquid depending on temperature and pressure, and are a relatively common material to get in pure state. iodine is also dangerous, but is not as reactive, and the others in the 2 colums are either solid, or are simply going to kill you for other reasons.

That 304 stainless series thin wall pot is really only rated for air, or water, at no more than 4 bar, as it will want to turn to a ball, and being thin wall it likely is just about capable of handling 6 bar before splitting along the side, from all the cold work that has been done shaping it. 1000 cycles of pressure to 4 bar likely will see it failing.
Capernicus:

--- Quote from: SeanB on March 10, 2022, 04:58:15 pm ---1000 cycles of pressure to 4 bar likely will see it failing.

--- End quote ---

Yeh would definitely take more than a pepsi bottle,  but u probably want a blast shield around that thing with a big heavy concrete lid on it under the surface of the ground. :)  Who'd want to trust the engineers involved, best to be safe and sure.


--- and---  only use 200 millilitres of it, and concrete the rest of the volume up inside.  Then see if the bastard can hit 20,000  hehe  (jk, i think im only going to use 200.)
TimFox:
"thats really interesting,  I'm planning on doing something alot more primitive than that.
I don't know what critical point even is."
An apocryphal statement attributed to Fats Waller:  "...if you don't know by now, don't mess with it!"
Have you looked at the document that Leica linked in the link I sent you above?
Capernicus:
Yes it was amazing,  but I didn't quite understand.

They had some good ball park figures there, I need to rebudget everything, theres more I need to know, definitely,  so I'm going to put the project off for a while yet for anything high pressure.

I'm just going to set up a little 100psi system (but with pure oxygen) and see if I get some cementing to happen.    If it turns out I'm completely off with everything I'll go for more reading.  I'm kinda a little restless at the moment, I want to see something happen with what I know now.

May just all fall apart in my hands, wont agglomerate at all.


(heres a vid of me with some gypsum chalk, I did it in a vibrating crock pot, and it was pretty tough, but yes I snapped it...)


I think you can actually have a "crock of shit" and it makes the poo go hard!  with slow high temperature evaporation! =) hehe
IanB:

--- Quote from: Capernicus on March 10, 2022, 03:25:42 pm ---thats really interesting,  I'm planning on doing something alot more primitive than that.
I don't know what critical point even is.

So even friction can set off liquid oxygen,  but what if its diluted in water,  is it less explosive?  Cause at 2000 psi I compute im still 90% diluted in water,  even tho my calculations could be way off!!!   So I better be careful.

Im actually "drying" something as well,  there is icy cold "mud" (with the magnesium oxide in a milk of cold water) in there and I want to evaporate off all the h2o over time in the presence of a gas (which accellerates crystalization, like an acid.),   so I was thinking of vibrating it and somehow transfering to a condenser nearby,  but maybe the friction will agitate the oxygen and might blow up...

If it turns out risky as hell,  I can make magnesium carbonate instead of magnesium oxide and ill be just as happy,  and it might be way less dangerous.

The carbonous acid counts as 1% when the oxygen-base counts as 10%,  ph wise.     at the same pressure.   But its only my dodgy calculations I'm not sure about any of it.

But!   If I just use compressed air instead of oxygen,  is that alot safer???
If I use pure oxygen I can probably get away with way less PSI...  so maybe if I use oxygen I should only limit the psi that goes in, to save my skin.


So whats more dangerous...  2000 psi co2, 2000 psi air -  or 200 psi pure oxygen?  (cause I think its the same effect on crystalization.)

At 200 psi, its probably 1% liquid oxygen (only by my dodgy calculations tho...),  I wonder if thats not as explosive?

--- End quote ---

Everything you are writing is incorrect.

The presence of a gas does not accelerate crystallization.

Acids do not accelerate crystallization.

Oxygen is not diluted by water, because oxygen does not significantly dissolve in water.

Oxygen is not an acid, nor is it a base.

You suddenly brought in carbonous acid out of nowhere. Where did you get that from?

Carbonous acid does not count as 1%, pH wise. That sentence has no meaning.

Oxygen-base is meaningless and does not exist.

Oxygen does not affect pH as it is neither an acid nor a base.

Liquid oxygen does not form by increasing pressure, 2000 psi or otherwise.
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