Guided waves based diagnostic imaging of circumferential cracks in small-diameter pipe

Area of Science:

• Materials Science
• Non-destructive Testing
• Ultrasonic Testing

Background:

• Pipeline safety and reliability are critical, driving research in non-destructive testing (NDT) methods.
• Ultrasonic guided waves (UGW) are effective for pipe inspection but struggle with precise defect localization in pipe features.
• Existing UGW methods lack the capability to accurately identify defects in critical pipe components like welds and supports.

Purpose of the Study:

• To develop a novel guided wave-based cross-sectional diagnostic imaging algorithm.
• To enhance the identification of circumferential cracks within pipe features, specifically welds.
• To improve the accuracy of defect localization in pipeline inspections.

Main Methods:

• Development of a guided wave-based cross-sectional diagnostic imaging algorithm.
• Implementation of an angular profile-based frequency selection method for enhanced imaging accuracy.
• Experimental validation using a 48 mm diameter type 304 stainless steel pipe with a simulated circumferential crack.

Main Results:

• The developed algorithm successfully identified the presence and location of a small circumferential crack.
• The crack, representing 1.13% of the cross-sectional area (CSA), was accurately detected within the welding zone.
• The angular profile-based frequency selection ensured high accuracy in the diagnostic imaging.

Conclusions:

• The novel guided wave imaging algorithm effectively identifies circumferential cracks in pipe features.
• The approach demonstrates significant potential for improving the safety and reliability of pipeline inspections.
• Accurate crack detection in welds is crucial for maintaining structural integrity.