Predictive Maintenance and Reinspection Strategies for Hydrogen Refueling Station Pressure Vessels: A Case Study in South Korea

Hydrogen refueling stations rely on pressure vessels capable of withstanding pressures up to 90 MPa while mitigating concerns related to hydrogen embrittlement. However, a gap exists in understanding the long-term fatigue behavior of these vessels under real operational conditions. This study focuses on evaluating the safety of SA372 pressure vessels using operational data from a hydrogen refueling station in Pyeongtaek, South Korea. A predictive reinspection methodology is proposed based on this evaluation. Parameters including hydrogen-induced stress intensity factor (KIH), initial crack size (a0, c0), and pressure vessel specifications are considered to assess critical crack depth (ac), critical usage cycles (Nc), and allowable usage cycles (Nallowed). Leveraging operational data collected between August and November 2023, fatigue analysis and Rainflow counting inform reinspection schedules. Results indicate a need for mid-bank vessel reinspection within the second year, high-bank vessel reinspection every 20 years, and low-bank vessel reinspection every 143 years, in accordance with safety regulations. Additionally, a revised refueling logic is proposed to optimize vehicle charging methods and pressure ranges, enhancing operational safety. This study serves as a preliminary investigation, highlighting the need for broader data collection and analysis to generalize findings across multiple stations.