The integrity of flexible risers remains a challenge mainly because in-line inspection (ILI) is not applicable. In addition, the variations in design of flexible pipe, the use in an offshore environment and the lack of experience in the failure mechanisms compared to rigid steel pipe add to the complexity.

Annulus Testing is an established method to investigate the well-being of a flexible riser. As an integral method it lacks the ability to pin-point to the root cause of the problem. A scanning method employing standard NDT methods is desirable for more accurate and specific testing. This could be limited to selected spots along the line or a complete scanning from the outside.

The paper and presentation will give an overview of the new developments and offshore experiences that have been gained at InnetiQs over the past years. A variety of scanning techniques are available ranging from a UT-based flooded annulus detection system (FADS) to an inspection method based on Eddy Current Technologies for the inspection of cracked wires in insulated riser.

The applied NDT-technologies are explained including the difficulties to establish a reliable testing environment including reasonable test samples and the influence of outer ambient pressure. In addition, operational challenges are described.