Rimsting, Russian Federation
Völklingen, Russian Federation
München, Russian Federation
München, Russian Federation
Mühlheim an der Ruhr, Russian Federation
Large rotor forged parts, which are usually one of the most critical components in land-based turbines and generators for power generation, require a complex volumetric test for a sufficient service life. This is usually performed manually or automatically with ultrasound. New requirements, designs and materials require more sensitive testing. This can be achieved by SAFT, also called ultrasound computer tomography. SAFT is based on the Synthetic Aperture Radar (SAR) and has been further developed by several universities. The introduction of SAFT in the volume production of large forged parts was achieved by the introduction of the quantitative SAFT developed by Siemens, also called AVG or DGS-SAFT, which allows an evaluation of each voxel in units of a replacement reflector, and by an acceleration that allows the reconstruction of the complete volume of a large forged component, which could be obtained when the SAFT test was introduced into volume production. The challenges for level 2/3 reviewers are discussed, such as volume-corrected display of results, handling of large amounts of data, focusing of displays, amplitude representation in units of a replacement reflector and handling of the software. Furthermore, it is shown how displays are represented by SAFT, how the detection limit can be determined in the case of quantitative SAFT, and which artifacts can occur during series testing with SAFT.
ultrasonic testing, quantitative SAFT, large rotor forged parts, implementation experience
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