MAGNETIC MEASURING SYSTEM FOR A FLAW DETECTOR HAVING LONGITUDINAL MAGNETIZATION

The utility model relates to the field of magnetic flaw detection, to devices for the non-destructive testing of pipelines, and to a magnetic measuring system for an in-line flaw detector. A magnetic measuring system for a flaw detector having longitudinal magnetization is based on units of combined sensors and makes it possible to detect flaws on the basis of a scattering field which forms where flaws are present, to determine whether a flaw pertains to the inside wall of a pipeline, and to image distortions in the shape of the inside wall of the pipeline, related to dents, transverse seams, etc. The units of combined sensors are installed on a cylindrical magnetic core of a single-section flaw detector by means of a ring of movable brackets between two rings of magnets having opposing polarity and elements which transmit magnetic flux to the inside wall of the pipeline. One unit of combined sensors consists of eddy current sensors and Hall sensors for measuring the transverse component of magnetic field induction, and of Hall sensors for measuring the longitudinal component of the magnetic field. An eddy current sensor, in turn, consists of two inductance coils which are combined into a module and positioned coaxially, one above the other. One of the inductance coils acts as a reference coil since it is located in a shielded compartment which is insulated from the external environment in the direction of electromagnetic current, and the inductance of the second, non-insulated, inductance coil is compared to the inductance of the reference coil. Un sistema de medición magnética de un detector de defectos con magnetización longitudinal dentro de tuberías. El sistema de medición magnética, el cual está basado en unidades de sensores combinados, consiste de unidades de sensores combinados dispuestas sobre un conductor magnético del detector de defectos de sección única con el uso de un anillo de soportes movibles entre dos anillos de magnetos/imanes de polaridad opuesta y elementos de transmisión de un flujo magnético a la pared interna de las tuberías. Una unidad de sensores combinados se compone de sensores de corrientes de Eddy, sensores Hall que miden la componente transversal de la inductancia de campo magnético, y sensores Hall que miden la componente longitudinal de la inductancia de campo magnético. Un sensor de corriente de Eddy comprende dos bobinas de inductancia combinadas en un módulo y dispuestas coaxialmente, una encima de la otra. Las bobi