As part of the Ipog (Inspection par Ondes guidées) project in GRTgaz's 2020 Internal Innovation Challenge, Mistras won the title of co-winner alongside the nine other entries selected from the 175 submitted, following a Guided Wave mission that took place at GRTgaz's Cuvilly station (60) in September 2019.
Set up by GRTgaz several years ago, this challenge enables the company to identify innovative solutions to unresolved problems encountered in-house, with real financial and/or safety implications.
GRTgaz was looking for a non-intrusive, efficient pipe inspection solution for checking wall penetrations without having to open the wall. Mistras convinced GRTgaz's innovation department with its Guided Waves solutions: the GWT (Guided Waves Testing) method, using GUL technology, and the GBW (Guided Bulk Wave) method, also known as HOMC (Higher Order Mode Cluster).
These two advanced NDT methods address the same problem: non-intrusive inspection of hard-to-reach or even "inaccessible" areas, from a single position.
While the GWT method enables long-distance control, the GBW/HOMC method uses short-range guided waves for medium-range control (up to 1 meter).
In some cases, the two methods complement each other: this was the case for the GRTgaz inspection, where GBW was used to check the soil-wall interface and GWT to inspect the rest of the wall.
Following GWT inspection, additional investigations other than GBW can also be carried out using other methods, such as the Touch Point Corrosion (TPC) method developed by Mistras to characterize the presence of under-support corrosion.
Focus on the GWT solution
- Rapid pipe integrity screening over long distances
- Limits heat and cold insulation removal
- Limits the number of scaffolding units
- Ideal for road crossings and non-scrapable pipes
- Solution for "inaccessible" areas: sleeve passages, gutters, floor inlets, wall penetrations...
- Helps prioritize and target additional NDT and inspections