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PostPosted: Sun Mar 11, 2007 12:32 am
by uberlad
the pneumatic cannon that i am designing has a 60mm diameter chamber that is approx 500mm long, which makes the volume 1.414 litres (86.3 square inches). it then leads into a sprinkler valve and the barrel is 500mm (19.685 in)long and a 20mm (0.7874 in) diameter. will the barrel burst when the cannon is fired? if so what psi
all pipe used is preassure rated PVC
i dont know if it would be possible for this to explode, but i would like to be sure beforehand in case i blow my face off
i live in australia, so all pipe over here is metric. i have included exact imperial measurements, but these are picky decimals, and i apologise for this inconveniance to those who prefer imperial calculations
p.s.
if it doesnt explode, can someone run it past the ggdt for me?

PostPosted: Sun Mar 11, 2007 12:38 am
by spuzi14
If you've glued correctly and you're safe with the compressor...it shouldn't explode.

The pressure rating should be on the side of the pipe. It should be in BAR I think but I really don't know. Due to it's smaller diameter, the barrel should be pressure rated to a higher pressure than the chamber since the chamber is a larger diameter.

GGDT is buried in some file and I don't have the time to dig it up or I would.

PostPosted: Sun Mar 11, 2007 4:00 am
by fullmetaljacket
Unless you've glued a very heavy projectile half way through the barrel, it's very, very difficult to burst the barrel of your cannon. The main concern is the chamber, that has to retain pressure for a lengthy period of time. If you've used pressure rated PVC, simply keep the pressure in the chamber below the rating.

Also, looking at your chamber dimensions, you can afford to increase your barrel length to 1000mm that will give a significant performance increase, as well as a quieter cannon.

PostPosted: Sun Mar 11, 2007 3:06 pm
by Velocity
Just to be sure, if you post the writing which is on the side of the pipe, we can tell you whether it will be safe to use or not.

PostPosted: Thu Mar 15, 2007 7:27 am
by uberlad
i havent purchased the parts yet, i was just hoping to run the stats by the forum, hoping not to waste money, or die from pvc in the face, thanks for the feedback