Non-Destructive Inspection of High Temperature Piping Combining Ultrasound and Eddy Current Testing

This paper presents an automated Non-Destructive Testing (NDT) system for the in-service inspection of orbital welds on tubular components operating at temperatures as high as 200 degrees C. The combination of two different NDT methods and respective inspection systems is here proposed to cover the detection of all potential defective weld conditions. The proposed NDT system combines ultrasounds and Eddy current techniques with dedicated approaches for dealing with high temperature conditions. Phased array ultrasound was employed, searching for volumetric defects within the weld bead volume while Eddy currents were used to look for surface and sub-surface cracks. The results from the phased array ultrasound results showed the effectiveness of the cooling mechanisms and that temperature effects on sound attenuation can be easily compensated for up to 200 degrees C. The Eddy current results showed almost no influence when temperatures were raised up to 300 degrees C.

Automated summary

This paper presents an automated Non-Destructive Testing (NDT) system for inspecting orbital welds at temperatures up to 200°C. The system combines ultrasounds and Eddy current techniques to detect both volumetric defects and surface/sub-surface cracks. The results show that the system is effective at compensating for temperature effects and has minimal influence at temperatures up to 300°C.