Copper pipe failure

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
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BC Pneumatics
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Even if a particular size copper pipe bursts at 2kpsi, a copper pipe system of the same size could fail much lower, since everything is soldered together. (I do not know if the joints fail at ~3x the pipe's rating, I am just throwing in my tuppence.)
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mark.f
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Look at it this way (In BC's observances on copper pipe failure): Pine trees are quite ductile, and bend a lot. But, in storms, a huge gust of wind will bend them, and then the gust will die, the pine tree snaps back up, and snaps in half somewhere midway up the tree. So, just because something is soft and ductile doesn't mean it won't fragment and create flying debris upon failure.
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POLAND_SPUD wrote:spudfarm did you talk with larda about pressure testing of various malleable iron fittings ? that's partly connected to the this thread you know...

I don't know who, apart form him, has stuff to do it... and I know that 150 psi is not exactly their real operating pressure
i am cleaned of money untill the hybrid is done.
but if noone buy the old hybrid (parts of it) i will send it to him. then it is a hole in a copuling with a sparkplug in it to be worst case.
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markfh11q wrote:Look at it this way (In BC's observances on copper pipe failure): Pine trees are quite ductile, and bend a lot. But, in storms, a huge gust of wind will bend them, and then the gust will die, the pine tree snaps back up, and snaps in half somewhere midway up the tree. So, just because something is soft and ductile doesn't mean it won't fragment and create flying debris upon failure.
You have given a great example to illustrate what I was saying. It is not just about the material, but also the circumstances.
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Hmmm...i wonder.
What if somebody was to use a section of copper pipe as a "sword" toy, and then have it be used as a chamber?
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If it still had the general shape of a pipe by the time you were done using it as a sword, you will be fine.
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Ooookay good.
My friend came over and chased me arouud w/ it and was also beating up some old yard junk
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DYI
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I just realised today that there actually are no pictures of copper pipe failure characteristics on this thread, and after the test I did today, I feel obliged to provide them. We couldn't find the entire pipe afterward, but these pictures give a good illustration of what has already been stated here.

Image

Image

Image
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@DYI, What did you do? it looks quite...crispy.
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i have a feeling that he cant tell you on the fourms :twisted:
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@DYI

lol, looks like a damn flower. I'm very curious as to what you did to it :twisted:.
but like drex said, whatever it was, it's probably not to be discussed on sf :shock:
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Thanks for posting the great pics DYI, you were right when you said they are a good illustration of what we've been talking about. It is not hard to imagine one of those banana peel segments detaching and flying at you like a razor.
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Mmm... but to be honest it looks like that pipe end was unsupported by a fittings socket (which would have reinforced it) and had an exceptionally high pressure spike inside it which had nothing to do with a gas combustion or pneumatic spudgun propulsion system.

Possibly an abnormally high powered hybrid firing heavy ammo might do that but for the purpose of normal spudgunning that kind of failure isn't likely to happen.
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VH_man
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the black residue is most likely carbon.

this shows me it was done with something that combusts "messily". meaning explosives. meaning poorly made black powder. meaning yes he cant talk aobut it......

still thats quite impressive. Looks like what happens when you fire a battery out of a 5X hybrid..........
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