J-tube pull-in is a conventional riser installation method used for connecting pipelines to offshore platforms. In general the J-tube pull-in analysis is performed either using simplified analytical models or finite element method. Finite element (FE) tools become more important for the scenarios with complicated J-tube design, because of its flexibility in adapting material properties, 3D geometry, and multiple bends.
Conventional FE models employ tube-to-tube contact elements (ITT elements in Abaqus) to model the contact between J-tube and riser, where both J-tube and riser are all modeled as beams. In this paper, a new FE model is developed that modeled the J-tube as a surface. The new model was benchmarked with the conventional ITT element model and shows a better performance in terms of convergence speed using a simple geometry. The new model was further applied to a 3D multiple bends J-tube application. The impacts from J-tube size, J-tube bend radius, number of bends, and material yield strength were also studied. The outcome of this analysis provides guidance for effective and reliable J-tube pull-in studies.
