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As the proportion of natural gas in China's primary energy consumption continues to rise, the construction of natural gas storage facilities in China has entered a period of rapid development to ensure the smooth operation of natural gas supply. However, the construction of natural gas storage facilities in China still faces many difficulties, such as deeper burial depth, poorer reservoir conditions, more fractured structures, more complex fluid compositions, and greater difficulty in building reservoirs in oil and water layers. On-site equipment is needed to meet both the requirements for injecting natural gas into storage and the production and operation functions. Through the variable inner casing head structure and the use of supporting blocks pushed by top threads to form bearing steps, some wellheads use metal-sealed choke hangers and the overall performance has reached an advanced level abroad.