Nuclear Power Plant Steel Liner

Its core function is to build the ultimate line of defense against the leakage of radioactive materials. As the inner sealing structure of the containment, the steel lining is made of low-alloy steel (usually 6-8 mm thick) and forms a continuous closed space through high-precision welding technology to ensure that radioactive materials cannot leak out during reactor operation or accident conditions. In extreme events (such as earthquakes, aircraft crashes, or ruptures in the main circuit pipeline), the steel lining works together with the external prestressed concrete shell, using anchor nails, reinforced steel and other structures to enhance the overall pressure resistance and seismic resistance, and can withstand a magnitude 9 earthquake and instantaneous high-pressure shocks. Modern third-generation nuclear power technology (such as Hualong One and AP1000) further adopts a double-layer containment design: the inner steel lining is responsible for sealing and radiation shielding, the outer concrete shell provides physical protection and heat dissipation, and the middle air layer is used for leakage monitoring and emergency gas emissions, forming a depth defense system. In addition, modular construction technology for steel lining (such as overall hoisting of the bottom head and laser positioning welding) has greatly improved construction efficiency. Its localization breakthrough (material and process autonomy rate of 85%) supports my country's nuclear power technology exports and has become a landmark component for the construction of international high-standard nuclear power plants. From a design life of 60 years to full-cycle maintenance-free requirements, steel lining has always been the key cornerstone of the safety and economy of nuclear power plants.