METHOD AND APPARATUS FOR CORRECTING MAGNETIC FLUX SENSOR SIGNALS

摘要

Apparatus for detecting defects in an oilfield string at a well site as the string is pulled from the well include a plurality of magnetic flux sensors 12 circumferentially spaced about the string, and a plurality of stand-off sensors 14 circumferentially spaced about the string for determining changes in stand-off distance between one or more stand-off sensors and an external surface of the string. Computer 18 corrects signals from the plurality of magnetic flux sensors as a function of the detected stand-off distance.