Mechanical analysis and software development of irregularly shaped pipeline in hoisting process

The hoisting of irregularly shaped subsea pipelines is a critical issue in offshore installation. To conduct rigorous mechanical analysis and ensure operational safety, the mechanical properties of irregularly shaped pipelines during hoisting are investigated using the finite element method (FEM) and a mechanical software for analyzing irregularly shaped pipelines is developed in C++ using the Visual Studio platform, featuring a user-friendly interface based on the Qt Creator. The mechanical characteristics such as von Mises stress, strain, and sling tension for three types of irregular pipelines under various construction conditions are calculated, and the results are compared with those obtained from the OrcaFlex software. Good agreement is confirmed by determined errors that fall within a range of 5%, validating the accuracy and reliability of the self-developed software. Additionally, the influence of pipe diameter and wall thickness on the mechanical properties of irregularly shaped pipelines is systematically analyzed. The high computational speed and accuracy, along with the user-friendly nature of the self-developed software, are demonstrated, thereby establishing it as a valuable tool for guiding pipeline installation and laying operations.