Parametric Analysis of Crushing and Squeezing Loads Over a Flexible Pipe During Installation Procedure

Launching of flexible pipes in deep water is one of the most critical operations since it can damage the metallic layers. The effects of installation loads on the pipe, such as the crushing applied by tracks of the caterpillars on the launching vessel and the squeezing resulting from the tensile armors traction are investigated in this paper. The aim of this work is to present a parametric analysis of variables responsible for the flexible pipe failure during laying operation. In order to perform this analysis, a tridimensional model using Finite Element Method is evaluated considering the actual profile of the metallic layers and the real geometry of the caterpillar tracks. Important parameters, as the stiffness of the caterpillar tracks and the installation loads, are analyzed to identify how these variables affect the yielding of the metallic layers. The investigations of the pipe failure based on the crushing and squeezing loads are stated considering different launching depths. The results of this parametric investigation are presented, and a safe configuration for the launching is proposed, based on the tridimensional model investigated and on in each of the analysis performed.