When it comes to transporting liquid or gas, the integrity of your infrastructure is everything. Any weak point can lead to costly failures, and yet, one of the most vulnerable areas in these systems—welded attachments—can be the hardest to inspect. From nozzles and valves to tees and bends, these complex components often pose inspection challenges due to their intricate shapes and varying geometries.

Common Attachments and Their Challenges

Common welded attachments include nozzles, valves, sleeves, tees, and bends. These components, however, are notoriously difficult to inspect due to their complex shapes, challenging geometries, and limitations in probe positioning.

Pipe system with reduction attachment, flange and T-joint

Pipe system with reduction attachment, flange and T-joint

Pipeline repair with a sleeve

Pipeline repair with a sleeve

To conduct a successful inspection, a precise scan plan and accurate drawing of the component are required. Manual inspection of these parts is not recommended, as the positioning of the probe must be exact to ensure proper volumetric coverage. This precision is essential to differentiate between geometrical echoes and potential defects.Welded branch nozzle flange

Welded branch/nozzle/flange

Lap Fillet Tee Fillet Corner Fillet

Manual UT Limitations

For the inspection of welded add-ons in gas and liquid transportation systems, manual ultrasonic testing (UT) is often employed. However, this method heavily relies on the operator's skill in identifying geometrical echoes while moving the probe or using manual ray tracing to interpret complex sound paths. This dependency introduces variability and limits the effectiveness of the inspection.

Conventional UT beam on a T-Joint Single A-Scan as a visible signal

Conventional UT beam on a T-Joint with a single A-Scan as a visible signal

Phased Array Ultrasonic Testing: A Step Forward

Phased array ultrasonic testing (PAUT) provides a significant improvement in coverage, allowing inspectors to visualize multiple beams simultaneously. This is especially beneficial for identifying geometrical signals during inspection.

Eddyfi Technologies’ portable PAUT instruments, Gekko® and TOPAZ®, take this a step further by offering onboard 3D imaging capabilities. This technology allows inspectors to visualize the part’s surface, inspection volume, probe location, and beam coverage directly on the acquisition unit, providing real-time insights and reducing errors.

PA ray tracing of a fillet weld on Gekko

PAUT signal plotted in the part geometry

PA ray tracing of a fillet weld on Gekko and the PAUT signal plotted in the part geometry

Seamless Setup and Execution

One of the standout features of these instruments is the ability to configure and visualize part geometries directly on the acquisition unit. The setup includes a list of part configurations with all necessary settings, ensuring the scan plan matches the component being inspected. This seamless integration between setup and execution reduces the risk of errors that can occur when scan plans and acquisition settings are done separately.

Configuration menu in Gekko

Configuration menu in Gekko

Final result with the probe, nozzle, beam ray tracing

Final result with the probe, nozzle, beam ray tracing

Real-Time Visualization and Reporting

Throughout the inspection process, the 3D visualization tool provides continuous feedback, allowing inspectors to identify and distinguish between geometrical echoes and potential defects. This real-time feedback enhances the accuracy of the inspection, and the 3D view remains available for data analysis and reporting, whether on the portable acquisition unit or a PC-based application.

The embedded 3D data provides clear flaw positioning within complex geometries, making it a powerful tool for reporting and analysis.

For nozzle inspections, particularly when assessing changes in carrier pipe geometry around the nozzle, the Gekko unit combined with a 3-axis scanner offers a unique advantage. The inspector receives live updates of the PA or total focusing method (TFM) signals overlaid on the part geometry, providing a comprehensive understanding of the inspection area.

3-axis scanner

3-axis scanner

Sectorial scan with the part overlay and 3D plot of a section of nozzle inspection

Sectorial scan with the part overlay and 3D plot of a section of nozzle inspection

Zoomed in on the flawed area

Zoom in on the flawed area

Conclusion

By equipping NDT inspectors with advanced visual tools like 3D imaging, they can more effectively distinguish between known reflectors and potential defects, increasing both the accuracy and confidence in their final reports. The ability to render complex weld geometries during preparation, inspection, and analysis offers a significant advantage, particularly when using Eddyfi Technologies’ Gekko and TOPAZ instruments.

For more information, check out our resources on TY fillet weld inspection and pressure vessel nozzle inspection. Expand your NDT knowledge by visiting the Eddyfi Academy, and feel free to contact us to discuss your next inspection campaign.