Optimization of K‐Shaped Metal Sealing Ring for Subsea Tubing Hanger Based on Response Surface Method

The K‐shaped metal sealing ring of the subsea tubing hanger is a crucial sealing component ensuring wellhead sealing. Optimizing its structure can enhance the sealing performance of the tubing hanger and improve the reliability of subsea wellhead equipment. Considering the numerous structural parameters of the K‐shaped metal sealing ring and the significant differences in their impact on sealing performance, a multifactor analysis method was applied to conduct a sensitivity analysis of the sealing performance. The results indicated that the outer contact width, inner lip width, and inner radius of the groove mouth are the three primary design variables affecting the sealing performance of the K‐shaped sealing ring. Taking these three structural parameters as design variables, with the objectives of improving the contact stress and contact width of the seal ring and reducing the equivalent contact stress, a multiobjective optimization model for the K‐shaped seal ring was established. To address the issue of low optimization efficiency due to the need for repeated finite element calculations during the optimization process, quadratic response surface models are established for the sealing performance indicators of the K‐shaped seal ring, which were then used as the optimization objective functions to enhance the optimization efficiency. Then, the optimized K‐shaped seal ring structure was ultimately obtained. A comparison of the sealing performance of the sealing ring before and after optimization revealed that the contact stress of the optimized K‐shaped seal ring increased by 6.44%, the effective contact width increased by 7.04%, and the maximum equivalent stress decreased by 14.54%. These results validate the effectiveness of the proposed method.