Schedule 10 SS Pressure Rating

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saefroch
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Sun Jun 26, 2011 7:40 pm

I have numbers, but I don't know how to produce an approximate pressure rating from them:

Wall thickness: 0.065" or 1.65mm
ID: ~.5"
Allowable stress: 16.7kpsi

I'm considering incorporating fittings of this size into an up-to-20X hybrid, but I'd like to make sure I'm not pushing the safety factor. I used a fitting with these measurements to 1,000psi in a pneumatic without incident, but that doesn't really say anything.
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DYI
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Sun Jun 26, 2011 9:04 pm

This puts your allowable internal pressure at 3.66 kpsi (using the distortion energy derivation for yielding. The thin wall approximation, which isn't totally invalid here, gives 3.34 kpsi) . The safety factor is, of course, already included in the "allowable stress" - even the weaker SS alloys tend to have yield strengths in the mid 30KSI range (in annealed state).
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saefroch
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Sun Jun 26, 2011 9:31 pm

Thanks very much. Looking at a max pressure of about 2.2kpsi for a 20x mix, it seems I'd be perfectly justified using sch 10 SS parts. :D

Of course I never thought to do this before. Idiot.
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