Engineering
The Challenge
During an ongoing fabric maintenance campaign on a mature North Sea offshore asset, areas of the external accommodation wall required repair to maintain the integrity of the accommodation envelope and support its pressurisation and fire protection requirements.
The project required a cost-efficient and flexible cold-work solution that could be deployed as defects were identified, allowing repairs to progress alongside the wider fabric maintenance programme without unnecessary delays.
A further challenge was presented by variations in the existing wall profile. The as-built geometry was not consistent across all areas, meaning a standardised patch design could not be applied universally. TEXO therefore needed to develop solutions capable of accommodating both general repairs and more complex, location-specific geometries.
The Solution
TEXO brought together expertise from its Engineering, Survey and Fabrication teams to develop a practical repair methodology suitable for the offshore environment.
For areas with complex geometry, profiles were moulded offshore using fibreglass. TEXO then digitally scanned the moulds, providing the Engineering team with accurate geometric information from which bespoke patches could be developed. This enabled location-specific components to be designed to fit correctly first time offshore.
For more general wall repairs, inconsistencies in the existing surface profile presented a different challenge. Rather than relying on an extended offshore trial-and-adjustment process, TEXO’s Fabrication team established an onshore trial, allowing the proposed patching methodology to be tested and refined in a controlled environment.
Through this collaborative process, TEXO developed a cold-work plate patch solution installed using self-tapping screws, providing the required pressurisation and fire protection performance.
The Fabrication team also supported the project with short-turnaround materials as requirements developed offshore, while the Engineering team revised and refined patch drawings in response to feedback from the ongoing works.
The Result
The developed methodology was successfully implemented by the offshore fabric maintenance team, with more than 100 defects repaired on the first accommodation wall.
By combining offshore profiling, digital scanning, engineering design, fabrication and onshore testing, TEXO was able to develop a flexible solution that responded to the variable as-built condition of the structure while reducing the need for lengthy offshore trial-and-adjustment activity.
The project demonstrated the value of TEXO’s integrated approach, with Engineering, Survey and Fabrication working collaboratively to take the repair challenge from initial assessment through to a practical, repeatable solution.
Following the successful completion of the first wall, the methodology and as-built information provide a strong foundation for similar repair works across the remaining areas of the accommodation structure.
