Title :
Automating an eddy current test system for in-service inspection of turbine/generator rotor bores
Author :
McCary, R.O. ; Viertl, J.R.M.
Author_Institution :
General Electric Co., Schenectady, NY, USA
fDate :
11/1/1988 12:00:00 AM
Abstract :
The comparison of the results of eddy-current testing and magnetic-particle testing of rotor bore sections shows satisfactory correlation if the eddy-current sensitivity is not excessive. Replacement of the present standard ferritic rotor bore tests with automated eddy-current testing thus allows continuity for recording purposes as well as improved repeatability and sensitivity where desired. use of eddy-current imaging techniques for automated processing, data extraction, and decision-making provides length estimates for surface breaking structures with error of about half a coil mean radius or less. A novel method, involving the surface integral of the threshold signal in the vicinity of an indication, can be used to estimate depth within 2:1; this capability is not available with magnetic particle data
Keywords :
automatic test equipment; crack detection; eddy current testing; inspection; maintenance engineering; rotors; turbogenerators; automated eddy-current testing; automated processing; continuity for recording purposes; crack depth estimation; crack detection; data extraction; decision-making; eddy current test system; eddy-current imaging techniques; eddy-current sensitivity; generator rotor bores; improved repeatability; in-service inspection; length estimates; magnetic-particle testing; rotor bore sections; surface breaking structures; surface integral; test system automation; turbine rotor bores; Automatic testing; Boring; Coils; Data mining; Decision making; Eddy current testing; Eddy currents; Inspection; Magnetic recording; System testing;
Journal_Title :
Magnetics, IEEE Transactions on