After 3 days of nothing done, some pressure vessel calculations, Day 13

After being busy and not being able to do much, I've done some calculations on the pressure vessel capabilities.

Brass 360 (the alloy I think I'm using) has a yield strength of about 45000 psi, and an ultimate tensile strength of 58000 psi. We assume a typical ASME factor of safety of 4. In the cross-section, the threads will be about 19.5mm in diameter, in a block of metal with a square cross-section of 1.5 inches on a side, leaving us with walls about 9.3mm thick at the thinnest. That means the wall thickness is roughly the same as the radius of the whole, meaning that, if we abuse the thin-walled pressure vessel equations, we can get roughly 10000psi internal pressure. Of course, thin-walled pressure vessel assumptions only work if the wall is roughly one tenth the radius, so in our case, we can make a very conservative estimate (remember, this is on top of the factor of safety) that 1000psi should be safe, at least in cross-section. And even that is an order of magnitude higher than we expect, so we will likely have a factor of safety of at least 100 if we carried out all the necessary calculations (and you include the ultimate strength). So this allows us to possibly survive a hard-start even if we start using liquid fuels, and also gives us some margin for changing of the properties with increased temperature.