Published: 01 June 2021
Structural safety | Risk management
Johan Castberg lies in the Barents Sea, 240 kilometres north-west of Hammerfest. The field is being developed with a floating production, storage and offloading (FPSO) facility and subsea templates tied back to this. The planned date for coming on stream in the original plan for development and operation (PDO) was the fourth quarter of 2022. Operator Equinor awarded the contract to build the hull with integrated living quarters to Singapore’s Sembcorp Marine (SCM) in November 2017.
Investigation
The PSA became aware in the first half of 2020 of weld-quality errors in the Johan Castberg FPSO hull. Extensive repair work is required.
An investigation was launched by the PSA to identify the reasons for the challenges in constructing the hull and equipment. This is also intended to contribute to learning lessons for future field developments.
Causes
A number of causes for these challenges have been identified by the investigation.
- SCM was a new fabrication contractor for Equinor
- Changes in construction sites
- Project organisation
- Concentration on project progress
- Follow-up of expertise and quality
- Risk management and reduction
Actual and potential consequences
Actual consequences
The quality challenges meant that the scope of inspecting hull welds increased to 100 per cent, and associated repairs will delay completion by about a year. The project now expected to come on stream in the fourth quarter of 2023, with a consequential reduction in present value as a result of delayed earnings.
Potential consequences
Inspection and repair cannot compensate for inadequate welding expertise. Full inspection of all welds is impractical, nor is it technically feasible for inspection to identify reliably all defects which might be present. Where details and areas are accessible for inspection and repair, some increase will be experienced in the expected need for maintenance and repair. Inaccessible details and areas will have a lower structural reliability than would have been the case if the welding had been done by competent personnel.
Nonconformities and improvement points
The investigation has identified four nonconformities related to
- risk reduction
- management of project execution
- qualification and follow-up of the contractor
- application of experience in dimensioning own follow-up.
- information to the licensees
- verification of fatigue analyses.
The PSA’s investigation has identified serious breaches of the regulations, and it has therefore issued Equinor with the following order.
Pursuant to section 69 of the framework regulations on administrative decisions, see sections 4 and 12 of the management regulations on risk reduction and planning respectively and section 18 of the framework regulations on qualification and follow-up of other participants, we order Equinor to review its systems for identifying risk in critical deliveries and for dimensioning its follow-up of suppliers to its projects, and to implement the necessary measures. See sections 8.1.1, 8.1.2 and 8.1.3 in the report.
The deadline for compliance with the order is 1 October 2021. We must be informed when the order has been complied with.