Patent ID: 8274280

Claim:
Device for nondestructive and noncontact detection of faults in a test piece, comprising: a stationary measurement means for taking an eddy current or magnetic stray flux measurements on a test piece and for producing measurement signals representative of said measurements; and means for positioning the test piece with respect to the measurement means in a plane perpendicular to the direction of movement of the test piece and for continuously advancing the test piece along a linear path of movement relative to the measurement means, a monitoring unit with at least three distance sensors arranged distributed in a peripheral direction around the path of movement of the test piece for contactless detection of the distance between the surface of the test piece and each of the sensors and for producing position signals representative of the distances between the test piece and each of the sensors, and a unit for evaluating said position signals to determine the position of the test piece with respect to said measurement means and wherein said measurement means is adapted for using the determined position of the test piece in evaluation of the eddy current measurement or stray flux measurement.