Analysis of Force Characteristics and Influencing Factors of Gas Storage Injection–Production Pipe String

Aiming at addressing the issue of seal failure of connecting threads of injection–production strings in gas storage, a theoretical research study of injection–production strings is conducted. A full-size model of an injection–production string is established by the finite element method, and natural frequency, buckling state, and influence factors are analyzed. Under the condition of ensuring the circumferential expansion displacement of the pipe string, appropriate annular pressure can be used to reduce the stress caused by the buckling of the pipe string. There is a pressure difference between the inside and outside of the curved section of the pipe string, and the larger the radius of curvature, the greater the pressure difference between the inside and outside of the pipe string, and the greater the fluid flow process because of the pressure difference variation caused by the vibration of the pipe string. The pipe string is in a sinusoidal or helical state near the packer position, and it has central symmetry. The variation in the pipe string outside pressure does not affect the position of the symmetric points. The research results can provide theoretical support to understand the mechanical characteristics and vibration mechanism of gas storage injection–production pipe string, identify the main control factors of vibration, and aim in the development of safety control measures.