Stress-analysis tool provides data on deepwater umbilicals

1 min read

Oceaneering Umbilical Solutions, the Rosyth-based deepwater cable manufacturer arm of oilfield services provider Oceaneering, has established a joint industry project (JIP) with Norwegian company Marintek to pioneer a predictive stress-analysis tool designed to improve the performance and longevity of deepwater umbilicals.

The tool — called UFlex (Umbilical Flexibility) — is designed to provide data based on the umbilical’s expected deepwater behaviour. Umbilicals carry an array of vital services such as hydraulic power for valves, signals for control systems and electrical power for motors, as well as communication cables. Given the nature of the environment, the umbilical can be exposed to immense stresses from its own weight and from tidal-wave and current forces.

Oceaneering Umbilical Solutions will incorporate a number of sensors into the umbilical, enabling its technicians to assess specific behavioural traits. As each umbilical technical specification varies, UFlex will be used to benchmark and standardise each bespoke configuration, so the data captured by the software tool can be used on future production runs.

The umbilical testing will be carried out in Oceaneering’s Testing Qualification and Research (TQR) facility in Rosyth.

Dr John White, global finite-element analysis and dynamic analysis manager at Oceaneering Umbilical Solutions, said that using UFlex will pinpoint stress- and fatigue-related issues that can have potentially damaging consequences.

’We need to have a better understanding of how an umbilical performs lying on the seabed. Umbilicals are exposed to a raft of internal and external pressures, tensions, torsions, bending and external contact loads, which may have an impact on performance,’ said White. ’We now have the ability to predict, during the development phase, what scenarios are likely to occur and make some headway in rectifying the causes.

’We want to see UFlex as the industry-standard “benchmark” programme that offers a novel way of allowing designers to study the use of different materials and various cross-sectional geometry — all through a laptop — which then limits the necessity for expensive, full-scale tests.’