0
$\begingroup$

Can polycarbonate be used to store a cryogenic liquid for a short duration, let's say 15-20 minutes.

I've heard that PVC will be really brittle at low temperatures.

What I'm trying to do is a rocket and I need a tank to store my LOX. I need it to be something like PVC or polycarbonate because they are light and cheap enough for my purposes. Also, they are often sold for tubing, the shape I need.

Any other suggestions of material will be greatly appreciated.

$\endgroup$
  • $\begingroup$ I would not use PC for this application because PC is very notch sensitive, so to have to drill holes in the tube for mounting or sealing is a big no-no. Also IMHO it is dangerous to be building rockets "on the cheap" because you will run into a situation where one of your rocket components will be under-designed because you used a cheap material. Be careful ! $\endgroup$ – William Hird Oct 21 '17 at 21:42
  • $\begingroup$ Virtually all plastics become brittle at cryogenic temperatures. Polycarbonate in particular would be extremely dangerous for this application since PC contains a considerable amount of water! Use a pressure tested metal container with the correct line fittings and please research the problem fully. $\endgroup$ – Donald Gibson Oct 22 '17 at 16:32
  • $\begingroup$ PVC and PC are entirely different materials. Neither would be suitable. $\endgroup$ – Donald Gibson Oct 22 '17 at 16:33
1
$\begingroup$

Short answer is no, as other commenters have suggested. The best solution is a small Dewar flask, which is stainless steel. Depending on how much you need, a commercial Thermos could do in a pinch. (Edit: I saw you want to use this for a tank on your rocket. If you are using it for a tank, there is not much in the cheap+light phase space. Cheap would be stainless and light would be titanium.)

As some unsolicited advice, liquid oxygen is very dangerous and if you are asking this question I would encourage you to read about the hazards associated with it a bit more. In particular, many things that you don't think are combustible will find a way to burn when they are impregnated or in contact with liquid oxygen. (Also, there are the obvious cryogenic hazards as well.)

| improve this answer | |
$\endgroup$
  • $\begingroup$ Yeah. I know what some plastics burn well with LOX. I'll probably just use GOX instead for my first tests. Also, I'll probably use aluminium. It's light, cheap and good enough for me. I think I know many of LOX's hazards. I've read a bit... Thanks! $\endgroup$ – Dat Ha Oct 26 '17 at 2:34
  • $\begingroup$ +1 for safety advice. The OP should read up on "Apollo 1 velcro". $\endgroup$ – user6335 Oct 27 '17 at 14:22
0
$\begingroup$

in designing the flask to hold your LOX, please note that the LOX will slowly warm up as it sits in the flask, and will then pressurize the flask. In addition to preventing heat loss and not being brittle at low temperatures, the flask will also have to be strong enough to withstand pressure buildup inside it without exploding.

| improve this answer | |
$\endgroup$
  • $\begingroup$ This answer is wrong in many ways. First of all, you don't answer the question. Second, LOX doesn't warm up. It boils, that's 7th grade science!. And for pressure build-up, I'll have a pressure bleed valve, so it doesn't need to stand that much pressure. $\endgroup$ – Dat Ha Oct 26 '17 at 14:09

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.