Posted by: Global Maritime | Date: October 7, 2020
As another decommissioning season draws to a close, we can take time to reflect on what we have learned. This year, Global Maritime’s London Office has provided Marine Warranty and Assurance services for 10 platform removals in the Southern North Sea (SNS) for Chrysaor, the UK’s largest independent North Sea oil and gas group. This directly followed a nine-platform programme in 2019 with the same client and contractors.
On paper, the 2020 campaign looked more challenging with a shorter run-in for the engineering and more, heavier lifts, not to mention the logistical complications the year brought. However, the experience accumulated over the preceding years meant the operations were remarkably efficient and consistently exceeded expectations.
Many of those involved in the project will look back on the lessons learned exercises of late 2019 and the subsequent actions as being instrumental to this. GM has worked on the project for over five years and through that period has amassed a formidable volume of knowledge on the intricacies of decommissioning in this area. Complex subjects which have been streamlined through constant collaboration between the client, contractor and MWS teams include:
• Optimised evaluation of on-bottom stability during leg cutting • Efficient structuring of safe-to-safe periods • Engineered selection of safe havens • Marine growth assessment • Benefits and limitations of numerous leg-cutting techniques • Grout integrity and practices of contractors in the SNS in the 80s and 90s • Internal lifting tools in complex joints • Condition assessment of ageing assets • Offshore backloading • Ensemble weather forecasting • Non-linear FE for maximising theoretical capacity of members • Non-reverse installation • Remote vessel and equipment survey
GM and our clients will benefit from this knowledge as we provide similar services for at least 20 more platforms around the UK, Irish, Dutch and Norwegian coasts over the next two years.