Need help with burst disc

[xxnelson18xx]

Hello everyone,

Although this is my first post, I’ve been around spud guns for several years. I’ve built several combustion and pneumatic cannons but recently decided to build a hybrid. I’ve constructed it using sch40 steel pipe and will by placing my burst disc in a 1.5” steel union. I’m wanting to use aluminum foil as my disc material. I don’t have a computer that will run HGDT so I’m hoping someone can helo me out. I’m going to be using a 3x oxy/propane mix but need to know how many sheets of foil to use. So basically, can someone tell me in a 1.5” union “x” number of sheets equals “y” psi burst rating?

Thanks for the help!!

[Zeus]

Short of personal experience, not really. Foil thickness varies from manufacturer to manufacturer. However, you're gonna be looking at a lot. Another option is aluminium barbecue trays, or soft drink/beer cans.

Can you correctly define what you mean by a 3x mix? Will it be pressurised to 3 bar, or are you using 3 times more fuel than a standard air/fuel mix.

[xxnelson18xx]

I will be using 3x more fuel then will pressurize the chamber to 3 bar

[Zeus]

3 bar with oxygen, or air

[xxnelson18xx]

I will be using an air compressor