COMPARISON OF CHARACTERISTICS OF SEARCHING SYSTEMS OF MOBILE MEANS OF RAILS OF RAIL DEFECTOSCOPY

Abstract

The characteristics of wheel-type search systems and sliding systems used for ultrasonic rail monitoring are considered, and their comparison is performed. It is shown that the use of a wheel-type system, the acoustic path of which contains a liquid medium with an increased propagation time of ultrasonic vibrations, limits the control speed to 60 km/h. It is noted that when passing a wheel-type search system of curved sections of track and rails with lateral wear, a change in the direction of propagation of the ultrasonic beam is observed due to a change in the tilt of the wheel relative to the rolling surface of the rail head, which reduces the reliability of detection of rail defects. The disadvantages of the wheel system also include a complex design, low maintainability, poor protection when operating at low temperatures and mechanical stresses, limitations on the ability to operate at high speeds, complicated alignment and, in general, the complexity of maintenance. The characteristics of the retrieval sliding system developed by the specialists of JSC Firma TVEMA are given that provide detection of rail defects with high reliability, operate at low temperatures, and realize a control speed of up to 140 km/h, including in curved sections of the track. The advantages of the proposed non-contact magnetic centering system of the search system, excluding mechanical contact with the rail and the dependence of the centering accuracy on the state of the working face of the rail head, providing unhindered passage of turnouts, including without reducing the speed of control, are presented.