Stainless Steel chamber rating's

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Lftndbt
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Thu Dec 06, 2007 8:06 am

G'day
I have done the obvious searches, with no luck...

So I was wondering....
Does anyone know if stainless steel tubing, has a minimum standard PSI rating?
I ask this because today at work I found a hidden stash of old Stainless tubing.... It's cheap because it isn't a carried line anymore.... But the manufacturer or any trace of packaging/PSI is long since gone....
I'm talking $8 AU for a 6metre length of 16mm Stainless with a wall thickness of 1mm, and $12 for a 6m of 30mm ....

Is there anyway of telling what PSI rating, it would have from the gauge or internal seam..? I am aware that most stainless for pressure is generally around your 1000PSI+ mark, just wanted to query you knowledgable folk, before using it for high PSI...
I would appreciate any help, because I can't hide these lil' babies much longer.... There is about 15 length's of each...
;)

Thanks in advance....
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Fnord
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Thu Dec 06, 2007 9:18 am

If you happen to know the grade/tensile strength of the tubing, we can give you a fairly accurate calculation of its working/burst pressure.

Using the wiki's yield strength for stainless steel I got a burst pressure of Over 9000(!!!) psi for the 16mm stuff, but this seems kinda high compared to what I was expecting.

Google wrote:520 megapascals = 75 419.6236 pounds per square inch
Anybody know if thats right? I thought stainless was lower than that.
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Lftndbt
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Thu Dec 06, 2007 9:38 am

_Fnord wrote:If you happen to know the grade/tensile strength of the tubing, we can give you a fairly accurate calculation of its working/burst pressure.

Using the wiki's yield strength for stainless steel I got a burst pressure of Over 9000(!!!) psi for the 16mm stuff, but this seems kinda high compared to what I was expecting.

Google wrote:520 megapascals = 75 419.6236 pounds per square inch
Anybody know if thats right? I thought stainless was lower than that.

No unfortunatley I do not know the grade/tensile strength.... I would probably be able, to work it out easily if I did....
It's basically just in a plastic sleeve saying "stainless steel" . I know it's definatley not curtain rail, that has a none pressure low quality seam. But i'm not sure if it's safe for high PSI, or PSI rated at all....

And it seems to have a fairly thick wall to it.... 1mm...
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Fnord
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Thu Dec 06, 2007 10:00 am

I'd buy it anyway... you'll probably find a use for it eventually and those prices are really cheap.

It'll work fine and be perfectly safe if you're sticking to lower pressures. (although these days I'm not sure what "lower pressures" are anymore... <300psi seems reasonable for the pipe you have)
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Lftndbt
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Thu Dec 06, 2007 10:12 am

300 PSI would be nice....
Now to get a shock pump..... :)
Should look nice with the stainless..... And yes I will buy it, like you said it is cheap....so why not....
I'm still going to purchase, some PSI rated stainless pipe for the next cannon... i'm not one to take chances... I get the shakes if i'm not 110% sure of the saftey of the gun.... I don't want to have to worry about it.... And i'm looking for 1000+PSI so unless anyone can convince me otherwise....
please do... :)

what I would like to know is....

Even if it is a low grade stainless with a low tensile strength. What would the likely minimum PSI rating be just from the fact that the material is stainless steel with a 1mm wall....
I am particularly concerned about the quality of the seam on the pipe... It looks good with no thinning of the wall at all.... but.... :(
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frankrede
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Thu Dec 06, 2007 10:03 pm

_Fnord wrote:If you happen to know the grade/tensile strength of the tubing, we can give you a fairly accurate calculation of its working/burst pressure.

Using the wiki's yield strength for stainless steel I got a burst pressure of Over 9000(!!!) psi for the 16mm stuff, but this seems kinda high compared to what I was expecting.

Google wrote:520 megapascals = 75 419.6236 pounds per square inch
Anybody know if thats right? I thought stainless was lower than that.
Redo your calculations using the lowest grade stainless you can find on the interenet, and that should be a good idea of a safe pressure
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Lftndbt
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Fri Dec 07, 2007 3:02 am

frankrede wrote:
_Fnord wrote:If you happen to know the grade/tensile strength of the tubing, we can give you a fairly accurate calculation of its working/burst pressure.

Using the wiki's yield strength for stainless steel I got a burst pressure of Over 9000(!!!) psi for the 16mm stuff, but this seems kinda high compared to what I was expecting.

Google wrote:520 megapascals = 75 419.6236 pounds per square inch
Anybody know if thats right? I thought stainless was lower than that.
Redo your calculations using the lowest grade stainless you can find on the interenet, and that should be a good idea of a safe pressure

I understand that, the lowest PSI rated gauge stainless has a minimum rating....
Yet I am more interested in.... In hardware terms is there a chance this could be light Stainless tube. It carries the name "Stainless steel" so buy law it must have the 10% chromium (??). It is definatley not plated.....
But the seam it worrying me.... should PSI rated stainless (be hard drawn??) not have a seam?
And would the seam be an indication of low quality/ non PSI rated Stainless tube...

Say in the worst case senerio, it was crudy curtain rail. (Which i'm sure it's not because the original price was over $100 AU)
but say it was.... tube I would imagine, would achieve a minimum PSI rating just from the fact that it is stainless and that it's tube...


I think I might pass up on these, because if there is even a 1 % chance it's no good... then it's not worth it...
I was just hoping for someone to jump in and say " Don't be a moron, it HAS to be above ___PSI because you can't physically make it less than that....
Anyway wishful thinking I guess, it's just so shiney!! Every time I walk past it, it keeps telling me to take it home and it wants to be an air cannon not shoved down the back of a shelf gathering dust.... ;)
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