Whether it is a rigid or a flexible pipe, the need for routine inspection and reliable analysis remains the same. Subsea pipelines and risers never stand still. To be confident in the state of these assets as they age is difficult, as so many factors come into play. With multilayered products, such as unbonded flexible pipes, threats come from many different directions. The inspection and integrity assessment of a standard carbon steel pipeline is an established and well-understood discipline. The flexible pipe world, however, having been with us for a significantly shorter time, is a different kind of challenge. But in their design process, natural redundancy was built in. Unlocking this redundancy and evaluating workable potential can produce significantly extended safe remaining life with a tolerable risk.


It is recommended that an Integrity Management strategy and program of inspection is implemented as early as practicable – and results recorded at regular intervals throughout an asset’s operational lifecycle. The more data an operator has, the greater the confidence that can be applied to any assessment of remnant life and integrity status of an asset. Our approach includes specialized FEA, free volume annulus testing and tailored inspection routines – uniquely extracting value from internal inspection – while applying internationally accepted codes of practice and following industry regulations and guidelines.


The aim of our work is to enhance safety and production assurance. Using the tools and technology that have already been developed is an effective way of achieving satisfactory management of a flexibles system and can very quickly pay for itself in sure-footed management decisions. Peace of mind follows when best practices are implemented and the threat of failure or loss of production is minimized.

Annulus Testing

Annulus Testing. ROSEN has established the capability of performing different types of annulus testing to meet market needs. These deploy vacuum or positive pressure testing and will always use innovative methods, processes and technologies. Getting reliable, repeatable data from annulus testing is the key to evaluating remaining life, as subtle changes in the annulus will occur over time. ROSEN has developed and laboratory-tested purpose-built equipment to improve the accuracy of annulus testing results, supported by a robust testing process. In practice, ROSEN supplies a team with significant experience in performing annulus testing, anywhere in the world. Technicians will be quickly mobilized to the site with compact, state-of-the-art equipment and be supported around the clock by principal engineers.


In-line Inspection. ROSEN has unrivalled knowledge and experience in interpreting data and reporting on the condition of internally inspected pipelines using magnetic, ultrasonic, eddy-current and mechanical technologies. During inspections of rigid pipelines, we have collected data for multiple flexible sections. We combine our expert knowledge of flexible pipe design, manufacture, operation and failure with an in-depth understanding of the physics of the inspection tools. We can utilize the data collected from these transits through flexible pipes to identify possible damage to the collapse carcass, excessive bending, end-fitting issues, loss-of-buoyancy modules, operational configuration and other information that can contribute to an understanding of the condition of the flexible.

Leveraging internal inspection data in this way does not provide all the answers, but it does add to our knowledge and contribute to improved safety.

Specialist Analysis and Verification

Specialist Analysis and Verification. A flexible pipe is subjected to variations in loads, which cause fatigue of the internal armor layers. With aging assets achieving longer and longer useful life in the oil and gas industry, operators are striving to understand fatigue life to more robustly predict safe remaining life.

ROSEN has the capability of performing the specialist analysis and verification needed to address these different types of stress and fatigue phenomena and associated failure modes. Our principal deliverable provides an indication of flexible pipe stress and fatigue condition, assesses remaining fatigue life and gives specialist advice for flexible pipe integrity management.

Ageing and Life Extension

Ageing and Life Extension. Life extension assessments are critical to maximizing the operational life of a flexible pipe. Whether initiated early or late in the operational life, the assessment allows for the fullest potential of a pipe to be realized. All types of assets are increasingly being re-evaluated to operate well beyond their original design life. To achieve this, operators may need to go through a procedural restructure if their current arrangements cannot effectively handle the amount of data generated by proper inspection. Under the requirements set out by safety regulators – which add additional pressure to the process – an overload of work for the operator can result, not to mention the engineering knowledge and skills that may be required. ROSEN has significant experience in developing a structured process to facilitate life extension for flexibles. We also deliver forward guidance on remedial actions that may be required at the same time, addressing future management challenges.