Inspection of irregularly shaped welds using adaptive TFM imaging
O Roy, D Leitao and L Le Ber
Eddyfi Europe, 1 rue de Terre Neuve 91940, Les Ulis, France
Irregularly shaped welds are very common in industrial structures, where weld-cap grind is not always necessary. As a consequence, the ultrasonic inspection is made very difficult due to the varying shape of the surface and back wall of inspected components. The authors developed an adaptive technique to compensate for irregularities in surface geometry and provide reliable diagnosis based on realistic imaging of the surface and back wall. This method is an adaptive version of the total focusing method (TFM), the adaptive total focusing method (ATFM), already available in real time on rugged portable equipment, the Gekko. First applications were thickness measurements below irregular weld caps. Data acquisitions have been achieved with linear scanners to merge several inspection positions to cover larger areas and to form realistic and robust images.
The ATFM has been implemented since on a new powerful system, the Panther, designed for automated inspection of complex structures. New applications are investigated to extend the ATFM solution to defect detection in irregularly shaped components. New results are presented to show the capability and the reliability of the method applied to components with various profiles.
