Objective
An international operator approached Imrandd to develop optimised late life strategies for pressure systems on its North Sea assets. Imrandd was tasked to carry out analysis of integrity and inspection data to create late life management plans to reach COP safely and in the most cost-effective way possible.
Scope of work
The late life optimisation followed Imrandd's data-driven approach to maximise use of the existing historical data, to identify equipment where inspection requirements could be removed or modified before COP. This, combined with Imrandd's engineering and technological capabilities, provided clear insight and justification for a revised late life strategy. The work was planned in five phases:
- Phase 1 – Data assessment (completed)
- Phase 2 – EXACT analysis and interpretation (completed)
- Phase 3 – Definition and update of MAWTs
- Phase 4 – Strategy optimisation
- Phase 5 – ALERT implementation
Phase 1 – Data assessment
Imrandd provided a thorough review of the available integrity and inspection data for pressure systems for three North Sea assets, including an appraisal of data available, allocations for risk, probability of failure and integrity status, historical inspections and current planned intervals and dates. Assessments covered both internal and external damage mechanisms for piping and vessel components:
- Internal/external inspection data extraction – gathered inspection reports, including internal/external integrity assessment data
- Data preparation – using EXTRACT and semi-automated QA/QC processes to format, cleanse and condition data provided by the client
- Determination of metrics covering quantity and quality of data available
- Basis of insights – relevant visualisations and summaries
- A view on remaining life and possible revision of inspection intervals, based on inspection data
Phase 1 results
Across the three assets, 14 to 19 years of data were reviewed – over 27,000, 23,000 and 1,900 test points respectively. The extraction process supported the identification of systems with the greatest opportunity for optimisation and further detailed analysis within phase 2.
- Majority of vessels identified for 'quick wins' were not major safety critical vessels
- Early quantifiable, scalable savings and justification to proceed to phase 2
- Continual checks and balances demonstrated an estimated 20–30% reduction in inspection scopes for phase 1
Phase 2 – EXACT analysis and interpretation
Imrandd deployed its proprietary analytics tool EXACT to accurately cleanse, correct and interpret the data, identifying 'good data' for trending, segregating extreme data, providing remaining lives of equipment and pipework, and identifying circuits and equipment where inspection intervals could be extended or removed to COP.
- Detailed analysis further optimised inspection scopes, recommending approximately 30–50% reduction across all three assets
- The recommendations are expected to realise considerable savings in inspection effort to COP and provide the basis for further reduction during phase 3
- Phase 3 will define appropriate MAWTs for use in the remaining life analysis, projected to bring further optimisation
