Non-destructive testing device for pipes. It extracts information on defects from signals captured by ultrasound receivers following the selective excitation of ultrasound transmitters according to a selected time rule. The receivers form an arrangement with a selected geometry, coupled in an ultrasound fashion, with relative rotation/translation movement, with the pipe. The device comprises a converter (891; 892) that selectively isolates a digital representation of echoes in designated time windows, as a function of the movement, and by extracting an image (901; 902) of defects, a filter (921; 922) which determines the presumed defect zones (Zcur) and the properties of these, a combiner (960) to prepare working digital inputs from an extract (951; 952) of images of a defect zone, properties of these coming from the filter, and contextual data (740), a neural circuit (970) receiving the working inputs, a digital decision and alarm stage (992) working on the basis of the output of the neural circuit, and a sorting and marking robot (994) for the pipes deemed not to conform by the decision and alarm step.