Establishing best industry practices for fatigue analysis methodology for steel tensile and pressure armours based on a thorough understanding of the relevant fatigue failure mechanisms
In collaboration with Equinor and Petrobras, DNV was able to consolidate industry practice for fatigue analysis of tensile armours (TA) and pressure armours (PA) in unbonded flexible pipes. In this Phase 1, the following activities were performed:
- Review of operators fatigue analysis methodology
- Review of manufacturers fatigue analysis methodologies
- Review of DNV fatigue analysis methodology.
Following the successful completion of these activities, DNV is launching a Joint Industry Program (JIP) Phase 2.
The general objective of the JIP is to have a consolidated methodology, validated and made available by DNV, in the form of guideline, for the analysis of fatigue in flexible products.
The phase 2 aims to validate the proposed methodology through a test program which cover all relevant aspects described on the guideline draft (phase 1) and thus ensures that the fatigue phenomena and its consequences are properly represented.
Project scope phase 2
The scope of Phase 2 is to further consolidate the fatigue design methodology by specific tests addressing the outstanding technical issues identified in phase 1. The main reasons for focusing on tests to further mature the fatigue design of flexible risers are:
- Perform dedicated test addressing specific outstanding technical issues
- Provide an independent test basis that will serve as basis for concluding open issues in the fatigue design guideline
- Provide a test basis for benchmarking manufacturers fatigue design methodology.
The estimated duration of this project is 3 years, expected to start in 2023.
A pre-project is undergoing during 2022, being financed and conducted by DNV with the support of stakeholders to refine both scope and cost.
DNV is open to discuss different R&D contract strategies with the stakeholders.