Application of SAFT in the Energy and Mechanical Engineering Industries

In the power generation industry, ultrasonic testing is an indispensable tool for the nondestructive testing of components that are subjected to high stresses during operation. Manufacturing inspections typically involve discs and shafts used in turbines and generators. The use of the Synthetic Aperture Focusing Technique (SAFT) offers several advantages in this context. In addition to more precise defect localization and better separation of adjacent defect indications, the improvement in the texture-dependent signal-to-noise ratio (SNR) is another important reason for using SAFT. This paper focuses specifically on the application of SAFT to cylindrical test specimens. In addition to comparing 2D-SAFT and 3D-SAFT, the main focus is on the resolution and spatial defect separation achievable with SAFT. The paper demonstrates how resolution can be determined through simulation and how this compares to an empirically derived formula in the case of a cylindrical disk. Using a specific example, the paper illustrates how resolution improves with increasing depth depending on the probe head used.