My new gun, and questions.

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
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Insomniac
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Well it is nothing special but today I decided to get the valve part of my old gun and attach it to a poly chamber and shorter barrel. This was for safety and to make it take less time to pump up.

I have a few questions though. On the chamber, the pipe says 'HR AUST PR 2420' I have no idea what the HR means, I'm guessing the AUST is because it is australian pipe, and I'm also guessing PR is pressure rating, and since kilopascals is the only unit that makes sence with that number I think the chamber is rated to 350 psi.

But I have no idea what the pvc ballvalve is rated to. It is a 20mm plastic pvc valve. From stuff I've read on the net I think it would be rated to around 150. How high do you think it is safe to use? I have already tested the gun to 120psi without a problem, and I am hoping that it will be safe to continue using at this pressure. I'll stick with 100 psi until I get an answer.

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I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

Add me on msn!!! insomniac-55@hotmail.com
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ALIHISGREAT
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if you don't know if its rated or not then i wouldn't use it, i would buy a different ball valve.
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Insomniac
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I'm sure it is rated because it is in the irrigation section of the hardware shop, and what is the use of a ballvalve that can't hold pressure? This valve has been used many many times at 80psi, I just want to know how much higher I can go.
I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

Add me on msn!!! insomniac-55@hotmail.com
Killjoy
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150psi is generally the standard for most plastic ball valves. But since you not sure what its rated I'd keep it at a 100 psi or below. Nice simple cannon by the way.
Stanford Class of 2012

"In the end our society will be defined not only by what we create, but what we refuse to destroy"- John Sawhill
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Insomniac
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The wall of the valve where the threads are is pretty thick, its about 6mm. That, along with the fairly small size of the valve, makes me think it is pretty unlikely it would fail at 100-120 psi.
I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

Add me on msn!!! insomniac-55@hotmail.com
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veginator
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I would trash it and go get a metal ball valve because the more times you use a plastic ball valve the harder it is to open and eventually you will hardly be able to open it at all. Another bonus is it can hold the high pressure that the pipe can.
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Insomniac
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Well today I went and got a metal valve, it is a little harder to open than the plastic one because of the shape of the lever, but I like it anyway because it is rated to 25BAR and I will be able to spring load it if I want (plastic ones just get stuck, they need pressure on both sides of the handle)

Does anyone know what polyethylene pipe is rated to????? I think I guessed correctly but it would be nice to know for sure.
I wonder how much deeper the ocean would be without sponges.
Right now I'm having amnesia and deja vu at the same time. I think I've forgotten this before.

Add me on msn!!! insomniac-55@hotmail.com
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