Which method is best suited for identifying discontinuities that lie parallel along a weld?

The method best suited for identifying discontinuities that lie parallel along a weld is Straight Beam Contact Testing. This technique utilizes a straight beam of ultrasonic energy that travels directly through the material being tested. Since the sound waves are transmitted perpendicular to the weld, any linear discontinuities, such as cracks or inclusions that run parallel to the weld surface, can be effectively detected and characterized.

In this testing method, the transducer is placed in direct contact with the surface of the material, producing a clear signal when it encounters a discontinuity. This direct measurement allows for a high level of sensitivity to discontinuities, particularly those oriented parallel to the weld, making it ideal for inspections in welds.

Other methods, while useful in different contexts, are not as effective for this specific purpose. Surface Wave Testing is more focused on detecting surface defects, while Angle Beam Testing is typically used for detecting flaws that are not aligned parallel to the sound beam. B-Scan Testing is a method used to visualize the internal structure of the material but might not provide the level of detail needed specifically for parallel discontinuities in welds.