I'm not currently building it,so there is not danger currently present... yet and 20,000 psi would just be the most 'efficient' in terms of size for the type of element that it is being used in accordance with. It could operate with lower pressures but the lower the pressure the larger it would be and more materials would have to be used, not only making it heavier but making it so it occupies more space. I have thought of a design around that is A LOT more complicated but still functions the same and does operate at a much lower pressure, but would take much more time to build. and probably result in higher manufacturing costs.
Sorry for the lack of information I am giving, this project is kind of secret to me and I feel like I've already given too much information.
Does anyone know of the highest PSI pressure vessel ever created for curiosities sake? I read the link you posted endy0816 and in the history part it does make it appear that even making a 10,000 psi vessel is a bit too dangerous. I guess I will ultimately have to do the design around, mathematically it would run more smoothly anyways.
Thanks guys.
@enthalpy
Thanks for the additional information as well, you posted while i was writing this. It seems my design around is most necessary.