A device for checkivng steel pipes during production and to a method using the device. The device includes a station for acquiring measurement data representative of physical measurements of the geometry of a pipe taken on an outside thereof, and a computer system configured to store template data applicable in a coordinate system and representative of overall geometry of a sizing body. In a chosen coordinate system, the system then provides a three-dimensional representation of parts of the pipe. For each part of the pipe, the system is referenced to determine a critical parameter, representative of the margin of passage of the sizing body inside a chosen part of the pipe. The method and device may thus establish a diagnostic of traversability of the pipe by a sizing body.