SpudFiles

well, guys just asking for some advise, im stepping up a step from piston valves to hybrids( don't worry I will always stay loyal to pistons ) I want this to be a reliability safe launcher and very high performance like breaking the sound barrier, at maby a 10x mix?, anyways the point of this topic is to show you what I have for now and so I need you to judge if this can handle these mixes safely, pipe is a foot of 3/4 galv steel, union 3/4 black iron, tee black iron 3/4, with a homemade brass/iron spark plug. Im going to add a sch80 pvc 1/2, 4 feet of barrel.What'd ya think guys?

thats a good idea about the O-ring, but i never heard it from you

Well Is this straight from the homedepot or some other hardware store?

What sch is it?

I guess its sch 40? but I thought this might be able to handle high pressures due to the small diameter, yes this is all from homedepot

That chamber looks a bit too long and skinny for my liking. Looks like a bit of a detonation hazard. It probably will be fine though. How do you plan on sealing the union? (there's no way that an o-ring will work).

The fittings and pipe look like the SCH 40 style to me.

Well the union sealed pretty well at 190 psi propane pressure
what it may ddt? but this pipe should be able to handle it right?

No it will not handle a ddt vey well at all. Sch 80 steel would survive a couple but this will get damaged if not fail completely.

I dont think this would be safe above 6x or 7x mixes unless all those fittings are special high pressure ones.
If they are ones from a hardware store then they will blow off for sure.
You would also need a special high pressure ball valve as the normal ones would have a chance of failing at that pressure.

So to sum it up, no it is not safe although others may disagree.

well the ball valve you see next to it is rated 3000psi, but the pipe is supposed to be for steam and high pressure gasses,I think, I don't really know, I talked to Fnord a few days ago and he said to could could take 15x mixes but that was his own educated guess, since I knew he had hybrid knowledge.

I don't know much about hybrids but I have a suggestion.. why don't we ask Larda "Would you be so kind as to test the burst pressure of some fittings for us ??"

we all know that galvanized fittings are not for high pressures but no one really know how much they can handle... it would be really good if someone check that for us - just the most common types of fitings and sizes.. I am not talking about pipes becasue there is info on them but we know almost nothing about fittings

elitesniper wrote:well the ball valve you see next to it is rated 3000psi, but the pipe is supposed to be for steam and high pressure gasses,I think, I don't really know, I talked to Fnord a few days ago and he said to could could take 15x mixes but that was his own educated guess, since I knew he had hybrid knowledge.

What about the fittings, what are they rated too, including the brass ones.
And were did you get that 3000psi ball valve?

You can get a foot of sch 160 for $28. here is the part number on mcmaster 7733K147. this could hold 15x most likely.

hey i have thinked about the Larda thing..
in a while i will send him some steel pipe from norway with ordinary endcaps and that stuff and get them burst tested.

i would never ever use this above 6x.
and i have used a O-ring in my union and it works at 6x with aluminium foil when i screw it with my hand.

BTW how big pipe should i use for the burst test? i thought of many short sections with copulings and many fittings to get it all tougheter so we can find out what burst at the lowest pressure.
mabe he can try the concrete reinforcement to.

That would be great. can you also ask him to test the iron fittings rated to 150 psi.

i don't know what i can get..
i probably just send him loads of assembled pipes with loads of fittings on.

i think i go for 2" and 1/2"

I ment malleable iron fittngs... steel fittings usually have pressure rating but we know almost nothing about malleable iron fittings..

@spudfarm I think it would make sense to send him different fittings in most common sizes like 3/4" ,1", 1.5" and 2"

i can look in my pocket and make a thread on what i should send for the money i got later.