The invention discloses a pulsed
eddy current detection method and
system for a thermal power pipeline with a
coating layer, and relates to the technical field of pulsed
eddy current nondestructive detection.The pulsed
eddy current detection method comprises the steps that pulsed eddy current detection
simulation and experiment are conducted under the condition of a three-
dimensional simulation model and a test piece, and
excitation current waveform, amplitude and frequency parameters are determined; an
induced voltage signal is collected, peak values, time points and attenuation characteristics are extracted, the corresponding relation between the wall thickness, the
coating layer thickness and the
welding seam structure and detection signals is constructed, a parameterized
database is constructed, and
temperature correction is completed; and optimizing a sensor structure and a
signal acquisition scheme according to a parameterized
database, obtaining detection data in a pipeline operation state, completing two-dimensional imaging of wall thickness distribution and
welding seam positioning, and forming detection information covering a straight
pipe, an
elbow and a
welding seam area. According to the method, wall thickness detection and welding seam positioning of the thermal power pipeline under the conditions of a
thick wall and a thick
coating layer are achieved through the full-
process design of test piece modeling,
simulation experiment and imaging collection.