pvc fittings. are they pressure rated?

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cork9
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Tue May 08, 2007 7:54 pm

while i was ordering my parts for my first air cannon[from mcmaster]it sais word for word !Do not use sch40 pvc fittings with compressed air they are not pressure ratted! The pipe is rated but not the fittings.How do u know this is safe.
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pyromaniac
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Tue May 08, 2007 7:57 pm

go to your local hard ware they will most likely have pressure rated fittings.
:pottytrain3:
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frankrede
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Tue May 08, 2007 8:00 pm

pressure rated fittings should have a NSF-PW label. not a NSF-DWV label.
This applies to fittings only because Pipe has both.
Current project: Afghanistan deployment
cork9
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Tue May 08, 2007 8:10 pm

If mcmaster dosent have it my local hardware store dosent have it.
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frankrede
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Tue May 08, 2007 8:14 pm

cork9 wrote:If mcmaster dosent have it my local hardware store dosent have it.
Ugh, ya they do.
MCMASTER HAS PRESSURE RATED FITTINGS
DON'T SAY THEY DON'T THEY DO
Current project: Afghanistan deployment
roderunner
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Tue May 08, 2007 8:28 pm

I think we're confusing pressure ratings for water and air.

No PVC pipe is rated for air. PVC tends to shatter, so all pressure ratings are for water only. Water is ok, because it's incompressible, so a break does not cause shards of PVC to fly everywhere. Air is compressible, so energy is stored in the pipe.

PVC manufactures, OSHA, and most everyone avoids using PVC for compressible gases.

http://www.osha.gov/dts/hib/hib_data/hib19880520.html
cork9
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Tue May 08, 2007 8:58 pm

ok so its saying no more than 100 psi witch was gona be my max anyway.
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hi
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Tue May 08, 2007 9:24 pm

they all say not for compressed air, every nsf-pw fitting i buy says that. its fine to use.
"physics, gravity, and law enforcement are the only things that prevent me from operating at my full potential" - not sure, but i like the quote

you know you are not an engineer if you have to remind yourself "left loosy righty tighty"
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