Numerical simulation on resistance of flexible pipe to radial compression

Flexible pipes are usually clamped by tensioners and other installation tools during installation.Too small clamping force may lead to the peeling of the oversheath of the pipe, while too large clamping force will lead to radial compression damage of the pipe.The three-dimensional finite element model of the complete section of the flexible pipe was established to predict the radial compression resistance of the flexible pipe.Through the radial compression simulation on the carcass structure of the pipe that was subjected to external compression, it was found that the carcass structure gradually evolved into a movable mechanism with four plastic hinges during loading.The compression resistance of the structure dropped instantly when yielding occurred in the structural area perpendicular to the compression direction.Further analysis of the compressive capacity of different structural layers of flexible pipes shows that the contribution rate of the carcass subjected to is only 39.01% of the whole structure, indicating an excessively conservative analysis on the compression resistance if only carcass is considered in the installation process.The research results can provide reference for the prediction of the compression resistance capacity of flexible pipes.