Research on Double Coil Pulse Eddy Current Thickness Measurement

The results of the thickness measurement is interfered by the effect of the lift-off in the pulsed eddy current detection. The traditional single coil measurement is inconvenient for the thickness measurement due to the influence of the lift. A non-contact measuring device based on double coil differential circuit is designed by theoretical analysis. It is proved that the measuring device can eliminate the lift-off effect to a certain thickness range through the experimental, the metal thickness conductivity and other parameters can be measured in a certain range.