Abstract: The apparatus is useful for monitoring integrity of casings, tubings, and other tubular strings in oil and gas wells. An apparatus for defectoscopy of downhole casings includes several units in a housing. An electromagnetic field generation unit generates excitation pulse of a specified amplitude and duration. It includes an exciter coil containing a core made a high magnetic permeability material. A pick-up sensor unit includes an integral pick-up coil and radial pick-up coils mounted around the exciter coil winding. Each pick-up coil has a U-shaped core with poles directed perpendicularly to the surveyed pipe surface and having a center line parallel to the center line of the exciter coil winding. A data control, acquisition, and processing unit includes operational amplifiers with variable amplification factors and analog-to-digital converters (ADCs) that transmit signals from the pick-up coils to software for casing defect analysis.

Abstract: The invention relates to geophysics and can be utilised for monitoring integrity of casings, tubings and other tubular strings in oil and gas wells. The essence of this invention is an apparatus for defectoscopy of downhole casings, which comprises an electromagnetic field generation unit, pick-up sensor unit, and data acquisition and processing unit, with all these units mounted in a housing. The technical result consists in enhancing the informative value of measurements in surveyed pipes both longitudinally and azimuthally, thus improving the defectoscopy accuracy.