eskimo3883 wrote:Hi,
I need to replace the lead ones as well. have 1800 psi & 2250 psi tanks but am not clear on their availability. Do I need to buy 1800 psi burst disks and 2250 burst disks or just use 3000 psi disks? Would moving to the 3000 psi disks put someone in jeopardy?
You should have no trouble finding burst disks /plugs for 2250 psi tanks. You also be able to find them for the 1800 psi ones but that may be harder.
I would definitely recommend against using burst disks for 3000 psi tanks on a 2250 tank (I realise cave divers did it, but then again that is cave diving

).
Using a disk for a 2250 on an 1800 psi tank is not ideal, but it is better than nothing.
My understanding is that bust disks are design to let go at 40% above working pressure. Hydro test pressure pressure is at 5/3 (or 66 % above working pressure) for most vintage steel tanks.