Which non-destructive testing method employs sound waves to detect flaws in welds?

Ultrasonic testing is a non-destructive testing (NDT) method that utilizes high-frequency sound waves to detect flaws in materials, including welds. During this process, a transducer emits sound waves that travel through the material being tested. When these waves encounter a flaw, such as a crack or void, they reflect back to the transducer, which captures the reflected waves. By analyzing these echoes, technicians can identify the presence, size, and location of flaws in the welds or the base material.

This method is favored in many industries due to its capability to detect internal defects and its versatility in testing various materials and thicknesses. Ultrasonic testing provides a detailed assessment, making it a critical component in ensuring the integrity of welded joints in pipelines and related facilities.

Other methods such as radiographic testing involve X-rays to visualize internal features, eddy current testing is primarily used for detecting surface defects in conductive materials, and visual testing relies on the inspector's sight and is limited to surface imperfections. Each technique serves specific purposes, but ultrasonic testing stands out for its effectiveness in detecting internal flaws using sound waves.