Discussion of the protection of pressure vessels by using safety valves-rupture disc-combinations

摘要

Due to safety requirements cryogenic facilities are equipped with safety valve-rupture disc-combinations against overpressure. Spring loaded safety valves in combination with rupture discs are designed as the "last resort" in the safety hierarchy to protect life and property. Under certain conditions while discharging, so called fluttering or chattering may occur. This behavior is defined as an extremely opening and closing of the valve. The associated mechanical loads can damage the piping and the equipment or cause pressure oscillations with high amplitudes in the inlet piping to the safety devices. This paper presents safety considerations in cryogenic test facilities for superconducting magnets and shows the reasons, the risks and furthermore the prevention of the oscillations.