Estimation of Impact Energy for Seat Seals in Spring-Operated Pressure Relief Valves During the Reseating Process Under Compressible Fluid Service Conditions

Spring operated pressure relief valves (SOPRVs) are used in many industrial fields for hazardous applications in order to protect people and environment as well as to reduce the risks of containment loss. Since SOPRVs are essential elements of safety systems, they are subject to strict functional and reliability requirements, which demand not only a proper disk lift but also give regulations concerning the maximum allowable valve tightness. However, despite the high practical importance of SOPRVs tightness through the whole life cycle, only initial tightness is considered in the literature and regulations. Therefore, in the present contribution we make an attempt to quantify the impact energy of the valve disk during the reseating of the valve, which is assumed to be the most relevant factor for repeated valve tightness. First, we present three different methods of increasing complexity for disk impact energy estimation. Subsequently, we demonstrate the application of these methods on the example of a SOPRV Type API 526 1E2 and discuss the findings. Finally, we consider a set of selected common used soft sealing materials and give implications for their usage within a range of set pressures and maximum disk lifts based on findings for the presented use case.