Burst Pressure Prediction of Subsea Supercritical CO(2) Pipelines

To improve transportation efficiency, a supercritical CO(2) pipeline is the best choice for large-scale and long-distance transportation inshore and offshore. However, corrosion of the pipe wall will occur as a result of the presence of free water and other impurities present during CO(2) capture. Defects caused by corrosion can reduce pipe strength and result in pipe failure. In this paper, the burst pressure of subsea supercritical CO(2) pipelines under high pressure is investigated. First, a mechanical model of corroded CO(2) pipelines is established. Then, using the unified strength theory (UST), a new burst pressure equation for subsea supercritical CO(2) pipelines is derived. Next, analysis of the material’s intermediate principal stress parameters is conducted. Lastly, the accuracy of the burst pressure equation of subsea supercritical CO(2) pipelines is proven to meet the engineering requirement by experimental data. The results indicate that the parameter b of UST plays a significant role in determining burst pressure of pipelines. The study can provide a theoretical basis and reference for the design of subsea supercritical CO(2) pipelines.