Patent ID: 7557570

Claim:
A method of producing a color contour map showing the locations, length, width, and depth of all surface defects within a chosen area of the surface of a high pressure pipeline, comprising the steps of: a. Calibrating each coil pair, each coil pair consisting of a send transducer coil aligned on top of a receive transducer coil, in a flexible array of transducer coil pairs to produce calibration coefficients for each pair; b. Storing the calibration coefficients in a microprocessor connected to the flexible array; c. Placing the flexible array of transducer coil pairs on the chosen area of the surface of the pipeline; d. Tuning a receive circuit connected to the coils to a resonant frequency; e. Sequentially and independently activating each coil, and activating in unison the send transducer coil and the receive transducer coil of each coil pair, operating the transducer coil pairs in a send/receive mode; f. Measuring the changes in magnitude of a signal from the receive transducer coil, and applying the calibration coefficients to those changes to produce calibrated changes; and g. From those calibrated changes, producing a color contour map showing the locations, length, width, and depth of the surface defects in the chosen area.