Sciencemadness Discussion Board

Home made stainless steel pressure vessel

Hazards79 - 23-8-2019 at 16:52

I’m looking for any advice or tips for making a 10 litre stainless steel pressure vessel that will be safe for basic chemical reactions. I’m a welder so that won’t be an issue I’m just after any hints or tricks from someone who has travelled this path

draculic acid69 - 23-8-2019 at 17:34

I've never done this but I have looked into doing it and there's something like asme 8 classes that welders take to get trained in making hi psi vessels. It's really a dangerous thing to do so planning it well is essential.will you need to heat the rxn vessel while under pressure?these vessels can be bought cheaply on eBay though not in that size. It might be acms not asme I can't remember but its one of the two.

Abromination - 24-8-2019 at 09:26

What basic reactions are you planning to do under pressure? This is a very dangerous thing to attempt in a home lab and even more so to use a homemade one. If you do it, take every precaution possible. Work behind a clear shatter proof plastic shield, wear thick clothing to prevent getting hit by shrapnel, check everything more then once and stay away from it when possible. Leave windows open all the way or work outside.

Fantasma4500 - 26-8-2019 at 23:17

i would suggest flange connection at top, this may be made by taking 2 pieces of steel plate, welding sides, drilling holes. super cheap solution you dont even bother threading one of the plates (i suppose threading both plates would be counterproductive) but instead just tightening it with bolts
i recall its something around several tonnes one single 14mm bolt can hold, AvE made a simple bolt-press this way, then you would want a sealant, silicone rubber would be ideal here, i think MAYBE some soft metal can be used if it can resist the chemicals?
i would also suggest welding in some flat bar steel rods or similar, inside of the container to strenghten it, also on the bottom

of course welding you would wanna use backing gas to prevent it corroding on the inside, butane might work. may just turn into carbon which would then require cleaning. imo more diy than helium regardless

the opening could also maybe be just a bolt in the side, but it would probably require silicone rubber every time you need to use it, maybe some silicone grease could work.

to prevent the whole thing fragmenting if it does burst you could attach some external frame or just weld some steelpieces on the sides attached to the bottom

it would of course be ideal to chamfer all the connections youre making before welding so you get 100% penetration without doubt, honestly a bunch of welding is totally overrated, welding is just held to such high standards so they cant blame the metalworkers when some drunk crane driver fucks up

i would suggest bottom plate to be smaller diameter than the pipe and pushed maybe 20mm into the pipe to be welded, mechanical leverage physics kinda thing

MrHomeScientist - 27-8-2019 at 11:47

What sort of "hints or tricks" are you looking for? If you're a welder with pressure certification, you surely know more about that side than we do. If you're asking about chemistry advice, you'd do well to refer back to your other thread. I hope this new thread isn't an attempt to distance yourself from the safety advice given over there. You asked about the chemistry, and people gave you very reasonable answers. We're just trying to help.

If you want more concrete evidence, here's a chemical compatability chart for stainless: http://www.quickcutgasket.com/pdf/Chemical-Resistance-Chart....
It doesn't have HI, but it lists iodine as "Severe effect - not recommended". Several other charts I found agree. It looks like about the only metal that works is titanium.

Fantasma4500 - 27-8-2019 at 23:08

it may be possible to coat the stainless steel with glass using sodium silicate, had a very sturdy layer of glass on stainless steel pot when i let some sodium silicate evaporate to dryness at around 60*C