The demand for higher inspection accuracies of in-line inspection tools is permanently growing. As integrity assessment procedures are being refined, detection performances, sizing accuracies and confidence levels regarding detection and sizing play an ever increasing role.

Inspection tools utilizing conventional ultrasound technology are at the forefront of technology and fulfill the market requirements regarding sizing accuracies and the ability to provide quantitative measurements. A draw back regarding their application in gas pipelines is their need for a liquid couplant.

This paper will introduce the concept for a new generation of intelligent pigs using a multi-technology approach to provide the advantages of ultrasound in-line inspection tools for gas pipelines. This new tool makes use of different non-destructive testing methodologies, offering true quantitative wall thickness measurement capabilities for gas pipelines, without the need for a liquid batch, thus significantly simplifying operational procedures. The measurement accuracy of the tool will ensure the data quality needed for advanced integrity assessment, including the issues of run comparisons, corrosion growth evaluation and upgrading of pipelines for higher operating pressures.

The paper will introduce the technology of the tool, its operational capabilities and defect specifications.