A Finite Element Model for Umbilical Cable Crushing Analysis

Abstract

Umbilical cables are essential elements of offshore floating production systems. Due to their complexity, the offshore industry regularly counts on numerical tools to perform design assignments. One of these assignments is to evaluate strains and stresses states in all components due to distinct sets of external loads. The main purpose of this paper is to present a numerical model for prediction of the stress and strain fields in the umbilical cable components under crushing loads. Such loads, outcoming from the laying operation, comprise the caterpillar shoes load and the squeezing effects, associated not only to the tensile armours, but also to helical components under tension. The referred model comprises a joint analysis using a two-dimensional Finite Element Method (FEM) fed by an analytical model, which represent three-dimensional effects. A combined analytical-numerical approach is much easier to implement than a complete fully three-dimensional one and it is meant to obtain results efficiently, without the need of a large computational capacity. The paper presents and discuss modeling hypotheses and methodology, describing in which way three-dimensional effects and interactions among cable components were treated. Case studies with three umbilical cables are presented.

Real-Time Stress Field Prediction of Umbilical Based on PyEf-U-Net Convolutional Neural Network

“…Due to the multi-component and multi-material characteristics of the umbilical, a large amount of contact and friction exists between the components, which can cause great difficulties when performing numerical simulations. Consequently, it has been found in existing studies [29][30][31][32][33] that certain parts are typically simplified in modeling due to the smaller contribution of these components to the overall strength of the umbilical. Cable is commonly simplified to the polymer dense-wrapped copper core structure, while the optical cable is simplified to polymer dense-wrapped steel shell structure.…”

Study on the mechanical characteristics of a fibre reinforced flexible pipe under radial compression loads

“…A non-linear analytical model of the equivalent ring considering the combined action of the carcass layer and pressure armour (Pesce et al, 2012) was also extended to consider the crushing problem of flexible pipes. Santos et al (2015) proposed a 2D numerical model to predict the stress and strain fields of an umbilical cable under a radial crushing load, while the displacement field was assessed using a high-resolution digital image correlation (DIC) system (Santos et al, 2016). Mendonça and Martins (2016; studied the stress and displacement of the carcass layer and pressure armour with parametric variations using the finite element method.…”

Modelo tridimensional em elementos finitos para a análise de cabo umbilical STU submetido ao carregamento de crushing.

“…Apêndice A: Apresenta a estratégia para o desenvolvimento de modelo bidimensional em elementos finitos para tratar do problema de crushing descrita nos trabalhos de Pesce et al [27] e Santos et al [39].…”