Strength concerns

[battlelava]

Does anyone have a rough estimate at what galvanized pipe is good up to, its not rated for pressure but its 1/4" thick so i'm guessing it can take a few psi. And do you think that a stick welder with 6011 rods (60,000 tensile strength) is enough or should i go 70k tensile strength rods. I was going to start with a combustion which I know is not a problem, but for when i make it into a hybrid I don't want it to rupture.

[Moonbogg]

It depends on the diameter. It also depends on how the end caps are held in place. You can hydro test it before using it as a hybrid. Fill with water and pump with a grease gun at a safe distance.

[jackssmirkingrevenge]

Does anyone have a rough estimate at what galvanized pipe is good up to, its not rated for pressure but its 1/4" thick so i'm guessing it can take a few psi.

Inner/outer diameter? And what mix number do you plan on taking it to?

[battlelava]

Should be 1" inside and roughly 1.3 outside. All welded edges beveled and weleded with 6011 rods. Max of like 10x.

[jackssmirkingrevenge]

That looks about right

[battlelava]

Would it be good to go 1" to 2" diameter with a flatbar in the middle with a hole in it

[jackssmirkingrevenge]

At 10x that flatbar will have almost 2500 lbs pushing on it at the moment of firing, how comfortable are you with your welding

[battlelava]

I feel good about it, specially with the 6011 rods as they burn through galvanized like its nothing and i give it a little extra heat to really burn in and get good penetration. I could also do a multi pass. Should 3/8" flat bar be enough or should i go 1/2"


Or should I try to find a 2" to 1" reducer so there's no blunt surfaces for pressure to catch

[Fnord]

Crowley and SB15 have used 2" sch40 steel pipe in 10x hybrids, and perhaps DYI/killjoy have too. I've taken it that high with a sealed vessel. The threads on pipe present a thin spot of roughly half the normal wall thickness, so if you're welding it you will have additional safety factor. For 2" pipe I'd go with 1/2" thick end plates if you have them, but 3/8" would still be sufficient, just make sure to run a really thick bead.

Put another way... 2" pipe caps are *nearly* flat on the inside, And they're no more than 1/4" thick.

[battlelava]

This pipes not threaded I was going to butt joint weld them together. I was going to ramp up the machine and really lay a fat bead like u suggested. I'm going to make a smaller version tomorrow. 3/4 barrel 2" chamber. Only 3/16 end plates and only low pressure 2x Max. See how well I can make this work