GEAR FOR INTRAPIPE MAGNETIC FLAW DETECTION OF WALL OF STEEL PIPE-LINES Russian patent published in 1998 - IPC

FIELD: aids for nondestructive inspection of walls of pipe-lines implemented by their magnetization and recording of magnetic leakage fluxes from defects. SUBSTANCE: gear has drive of longitudinal movement, power supply unit, recorder, flaw detection unit, rotation drive and transducer of defect coordinates positioned into examined pipe-line and coupled mechanically. Characteristic feature of gear lies in positioning of magnets and multilink converters in flaw detection unit on two rotors uniaxial to pipe-line and rotating in opposite directions. Magnets are so put on rotors that their poles are separated by directions of their movement along spiral trajectories relative to pipe-line. Converters are mounted between poles of magnets so that their links are arranged in row along lines perpendicular to directions of their movement. Drive of rotation of rotors is so manufactured that their rotational speeds are synchronized with speed of longitudinal movement of gear along pipe-line. In particular these speeds can be equal, magnets being spaced along directions forming angle of +45 deg on one rotor and angle of -45 deg on the other rotor with regard to generating line of pipe-line. Drive of rotation of rotors may be formed by drive of longitudinal movement and by supporting-running wheels obliquely mounted on rotors. EFFECT: enhanced functional efficiency of gear. 26 cl, 21 dwg