SEA developed a technically feasible shore crossing solution that provided flexibility for staged development of future assets, and demonstrated that it complied with all technical, environmental and safety requirements for the environmentally sensitive location.
A local operator’s team sought an understanding of the long-term stability of their pipelines and the residual risks presented if they were to be abandoned in place.
The MOBILEspan JIP reduces OPEX by more accurately modelling transient freespans with a methodology that combines seabed scour research with freespan response models and probabilistic analysis.
SEA analysed available data and developed a detailed roadmap of all activities needed to support life extension of a network of flexible subsea flowlines, ultimately avoiding significant CAPEX needed for replacement.
SEA delivered value to CalEnergy Resources by developing:
SEA delivered value to the Chevron Wheatstone scope of work through:
SEA was commissioned to investigate the feasibility of extending the service life of four original Wandoo flexible flowlines by 5 years beyond their original 20 year design life. The objectives of the feasibility study were to identify any potential barriers to extending the operational life of the flexibles and develop the associated risk profile for life extension. This study supported VOGA in making a high level decision on life extension versus flowline replacement.
Once the decision to extend life was made, VOGA requested that SEA prepare a Scope of Verification for approval by Lloyd’s Register.
SEA has delivered value to the VOGA Life Extension Project through:
Wave and current forces during a pipelines lifetime can scour the seabed beneath it, creating freespanning pipeline sections. These freespans must be analysed to assess their integrity. However standard assessment approaches are excessively conservative as they do not model the time-transient nature of the span configuration. This shortcoming in modelling leads to unnecessary freespan interventions, i.e. increased OPEX.
In 2013 SEA developed a concept to improve the analysis of transient spans and the understanding of their integrity. Together with the Industry Technology Facilitator (ITF), the MOBILEspan Joint Industry Project (JIP) was formed in 2013 in partnership with 4 multinational operators to develop this concept into a robust analysis methodology and calculation tool. The foundation of MOBILEspan’s success was that it combined diverse fields of existing knowledge and capability; span modelling, scour research and structural reliability analysis; to define a solution with a clear path to implementation.
SEA delivered value to the JIP partners through the following outcomes:
SEA was commissioned to develop an understanding of the stability behaviour of pipelines due to be abandoned in place. The overriding concern was the uncertainties surrounding longterm behaviour of the pipelines as they degrade over time, which may have presented challenges to the chosen strategy.
SEA was able to use local research outcomes from the STABLEpipe JIP to demonstrate that the pipeline ends needed no secondary stabilisation following abandonment, and that their behaviour as they degraded presented no significant consequence to surrounding assets or the environment. SEA’s analysis report supported the operator’s application to the regulator for the abandon in place strategy.
SEA delivered value to the operator’s team through:
SEA completed a concept and technical feasibility assessment for a multi-component micro-tunnel option for a beach crossing to support future Chevron projects. Micro-tunnel construction offers a density advantage for shore crossings, and can allow flexibility in usage even after tunnel construction has concluded. To avoid extending beyond allocated real estate at the shore crossing location, an alternative to HDD was required and SEA was able to leverage their experience with previous micro-tunnel construction to deliver a solution.
SEA assembled an experienced pipelines concept team, including specialist micro-tunnel and HDD consultants, to identify potential solutions and perform comparative risk and schedule reviews to develop a technically feasible solution for the range of future assets.
SEA delivered value to Chevron through:
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