Method for improving defect detectability with magnetostrictive sensors for piping inspection

A method for improved defect detection within a pipe or tube, utilizing a single magnetostrictive sensor, comprising the steps of:

• exciting said magnetostrictive sensor using a broadband frequency signal so as to generate a broadband spectrum of mechanical waves within said pipe or tube;
• receiving reflected mechanical waves over a period of time with said magnetostrictive sensor, said reflected mechanical waves deriving from and characterized by physical features of said pipe or tube and by an interaction of said pipe or tube with a fluid material contained within said pipe or tube, said magnetostrictive sensor generating an electrical signal having time varying amplitude and frequency characteristics corresponding to said reflected mechanical waves;
• amplifying said electrical signal with a broadband frequency signal amplifier;
• digitizing said amplified electrical signal;
• transforming said digitized signal using a short-time Fourier transformation technique;
• identifying patterns in said transformed signal relative to time and frequency axes for said transformed signal data;
• distinguishing at least one of said identified patterns relative to said time and frequency axes in said transformed signal data as associated with a geometric feature of said pipe or tube under inspection;
• and
• associating identified patterns not distinguished as associated with a geometric feature, with defects within said pipe or tube under inspection.

A method for improved defect detection with the use of sensor based NDE techniques, comprising the steps of:

• generating a broadband interrogating signal;
• receiving a reflected signal over a period of time;
• amplifying said received signal;
• applying a time-frequency transformation technique to said amplified signal;
• identifying patterns in said transformed signal relative to time and frequency axes, said patterns not associated with geometric features of an object under inspection;
• and
• associating said identified patterns with defects within said object under inspection.