Design of Spring Loaded Safety Valves with Inlet and Discharge Pipe against Chatter in the Case of Gas Flow

Pressure loaded installations are often protected against overpressure by spring loaded full lift safety valves. Damage to the relief valve itself or to the piping and equipment can result from the so called chattering of the relief valve during discharge. With all sizing rules a maximum allowable inlet pipe length can be calculated for which no chatter should occur. Experiments have been performed with the objective of checking the validity of these rules. The results is that none of the sizing rules is capable of predicting the safe allowable inlet pipe lengths for all given experimental conditions. Based also on experimental results taken from the literature, a modified pressure surge sizing method is recommended.