Rupture Disc Monitoring Using Electro-mechanical Impedance (EMI): A Feasibility Study

Rupture disc is widely used in pressure vessels. To prevent catastrophic overpressure in pressure vessels, it is vital to replace the rupture disc before its premature failure. This paper presents a systematic and comprehensive study of EMI-based rupture disc monitoring. A PZT actuator-driven one-degree-of-freedom spring-mass-damper model was established, and the analytical result shows that the EMI is determined by the local stiffness of the coupled structures. Since the stiffness of a clamped rupture disc is mainly controlled by its inner pressure, the operating conditions can therefore be estimated by measuring the impedance signal. To verify this finding, a numerical model is built and the simulation result shows that as the pressure increases, the resonant frequencies of the impedance signals decrease gradually. Conventional simple domed rupture discs were tested for validation experiments. Three replacement matrices (RMs) were proposed and compared based on the root mean square deviation (RM_RMSD), mean absolute percentage deviation (RM_MAPD), and correlation coefficient deviation (RM_CCD). The optimum rupture disc update time can be determined by the calculation of the RM_MAPD. In addition, the influences of temperature variation on EMI signals were investigated and a temperature compensation method was proposed. Experimental results demonstrated that EMI-based rupture disc monitoring is an effective method of preventing the occurrence of catastrophic overpressure accidents in pressure vessels.