PROCESS OF ULTRASONIC INSPECTION OF RAIL HEAD Russian patent published in 2002 - IPC

FIELD: non- destructive test of materials, ultrasonic flaw detection in rails and other long-length articles. SUBSTANCE: enhanced reliability, authenticity and productivity of ultrasonic inspection of rail heads are achieved thanks to installation of pair of inclined electroacoustic converters on roll surface of rail head in symmetry with its longitudinal axis and to their development through equal sharp angles with regard to longitudinal axis of rail towards sides of rail head. Converters are moved along longitudinal axis of rail emitting and receiving ultrasonic oscillations in specified time zones. Parameters of received oscillations are employed to make judgment on presence of flaw. Angles of input of ultrasonic oscillations into metal of rail and development angles of converters are chosen from condition that axes of ultrasonic rays reflected from zones of radius passage of side and lower faces of rail head on longitudinal axis of roll surface cross. Presence and orientation of flaw is visualized with the aid of joint analysis of signals received by converters. Echo signals from probable flaws are isolated in three time zones. First zone is intended for reception of echo signals reflected from flaws in side of rail head while exposed to sound with direct ultrasonic ray. Second zone is meant for reception of echo signals once reflected from radius passage of side and lower part of rail head while exposed to sound with ultrasonic ray. Third zone is meant to receive signals emitted by one converter and received by another converter after reflection of ultrasonic ray from corner reflector formed by lateral crack and roll surface or horizontal crack. Judgment on position of crack in rail head and on its orientation is passed by joint analysis of received signals. EFFECT: enhanced reliability, authenticity and productivity of ultrasonic inspection of rail heads. 1 cl, 2 dwg