For selected aircraft NDE tasks, prototype SQUID systems were developed and tested in realistic environments, demonstrating the practical usability of mobile HTS SQUID in conjunction with the eddy current technique in nondestructive evaluation of highly safety relevant object. The development of planar HTS gradiometers and orientation-independent cryogenics made possible the mobile use of SQUIDs in hostile environments such as airport hangars. The sensors are mounted either in a position-independent miniature cryostat with a liquid nitrogen hold time of up to 12 hours, or on a Joule-Thomson machine-cooler only requiring electricity. Tested in the Lufthansa wheel inspection facility at Frankfurt airport and the DASA at Bremen airport, the SQUID gradiometers worked successfully under electromagnetically noisy conditions. An automated test stand for SQUID testing of aircraft wheels, with the wheel slowly rotating and a robot with the SQUID enclosure scanning stepwise along the wheel axis, detects deep cracks smaller than today's limit of conventional eddy current devices. Further development in the spatial resolution and data analysis will improve the performance. Another SQUID system has been successfully operated on a professional fuselage scanner. Using a signal processing software, first and second layer cracks were detected adjacent to rivets.
Aircraft wheel and fuselage testing with eddy current and SQUID
Prüfung von Flugzeugrädern und Flugzeugrumpf mit Wirbelstrom und SQUID
1998
8 Seiten, 11 Bilder, 14 Quellen
Aufsatz (Konferenz)
Englisch
Aircraft fuselage inspection with SQUID systems
Tema Archiv | 1998
Mobile HTS SQUID system for eddy current testing of aircraft
Tema Archiv | 1997
|Aircraft wheel testing with machine-cooled HTS SQUID gradiometer system
Tema Archiv | 1999
|Aircraft fuselage section, aircraft fuselage and aircraft
Europäisches Patentamt | 2023
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