Overview: Nexxis was asked to help assist with a method to measure an internal weld section of a subsea pipeline being fabricated in a workshop. The welds in this case were approximately 2-30 meters deep from the entry point or pipe end. Our solution was to use a GE Mentor iQ Borescope.
Details: A section of CRA clad pipe was welded. The end user requirements were to measure the internal height of the weld and defects such as undercut, the tolerance was 0.1mm depth and length +1mm which was critical for subsea installation
Method of measurement: Considering the size of the pipe and also the criticality, Nexxis suggested a Mentor iQ, a borescope used in the aviation industry for internal jet engine inspections that can also measure well within the specifications.
The section of weld that is to be measured is shown below.
Shooting an image is simple and once done, measurements are done by the Stereo option. Using the ‘Depth’ option, a triangulation is created beside the weld profile and then scanning the point to be inspected.