Propane tanks are required to have a safety relief valve. The relief valve is a safety device on the propane tank to vent excess pressure.

Rupture disk are perfectly available as replacement of sfaety relief valves if you will consider that they are non-reclosing. In the case of an activation the pressure relief opening will remain open afterwards, where in the cas eof safety relief valve the device is reclosing.

pressure relief valve relief the excess pressure which is developed in the syatem, while pressure reducing valve reduces the pressure and supply it to the system.

A rupture disk (disc) is a pressure relief device that reliefs pressure when the pressure inside the protected equipment exceeds the set pressure. A fusible plug reliefs pressure when the plug is weakened due to high temperature.

If your pressure relief valve is adjustable, you increase the pressure relief setting.