Strength and tightness analysis of wellhead flange connections considering ultrahigh-pressure conditions

In high-pressure gas production environments, the reliability of wellhead flange connection is paramount for ensuring overall wellhead safety. Failure to meet stringent requirements regarding strength and stiffness under extreme conditions, can potentially lead to leakage and even catastrophic blowout incidents. To tackle these challenges head-on, a comprehensive performance analysis methodology is proposed for ultrahigh-pressure (UHP) wellhead flanges, integrating advanced simulation techniques with precise experimental measurements. Addressing the inherent difficulties in directly measuring moments under complex loading scenarios, an innovative approach is employed to estimate the ultimate moment using deflection angles. The study meticulously evaluates the strength and stiffness of pivotal components by leveraging a comprehensive finite element model of the flange. Detailed examination of valuation criteria and calculation procedures for determining the failure boundary conditions of strength and stiffness enriches the understanding of the flange's mechanical behavior under extreme operating conditions. Illustrating the practical applicability of the proposed methodology, a real-world case study of a UHP wellhead flange is presented, showcasing the efficacy of the approach through rigorous strength testing, resulting in the derivation of reliable mechanical performance parameters. Furthermore, the robustness of the proposed models is thoroughly validated through meticulous comparison of simulation results with empirical experimental data.