Bs
When the bursting disc fails the pressure will rise allowing a remote indication or alarm to be triggered.įor safety reasons bursting discs must not break up on failure. Valves normally leak slightly so the pressure under the safety valve will be equal to the safety valve back pressure. Pressure instrumentation can be fitted to the pipework between the bursting disc and the safety valve. The bursting disc can be replaced at the earliest convenient opportunity. On returning to normal conditions the safety valve reseats and seals. With excess pressure the disc fails and the safety valve relieves. During normal working the bursting disc provides a perfect seal. Before the safety valve is best normally the valve is not pressurised or subject to corrosion.
The bursting disc can be fitted before or after the safety valve. When handling the most hazardous fluids, bursting discs can be used in conjunction with safety valves to provide protection. Before failure bursting discs are completely leak free.
Unlike most safety valves it cannot close when the excess pressure condition has past. On increasing pressure, the membrane fails and allows fluid to escape. It may be relieved locally to produce stress raisers which dictate the failure mode. The membrane is very thin in comparison with the other pressure containing parts.
In Handbook of Valves and Actuators, 2007 Special Note: Bursting discsīursting discs, or rupture discs, are thin membranes which act like a blank flange.