pvc fittings. are they pressure rated?

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
cork9
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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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go to your local hard ware they will most likely have pressure rated fittings.
:pottytrain3:
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frankrede
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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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If mcmaster dosent have it my local hardware store dosent have it.
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frankrede
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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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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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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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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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