Research into causes of the appearance and development of rail inspection unsuitability in the moun-tainous area from Bol’shoy Lug station to Slyudyanka station

Abstract

With the development of contact fatigue damage, cracks and fractures appear on the working surface of the rail head, which make the rail unsuitable for inspection, since they prevent the detection of internal defects during ultrasonic inspection of rails with a flaw detector. In 2023 alone, in East Siberian Railway 2 169 defective rails were identified according to code 19. During the same period, 1 061 rails were identified along the Slyudyanskaya track distance, which is 49% of the total. In addition, by December 2023, the number of rails with such a defect increased 1,6 times as compared to January for the East Siberian Railway and 3,2 times for the section of track from Bolshoy Lug station to Slyudyanka station. The article is devoted to the study of the reasons for the appearance and development of rail defects (defect code – 19). This work is aimed at uncovering problem areas during the operation of the track in curves of small radii on mountain pass sections. The calculation of the contact pressure from the rolling stock on the track has been performed, taking into account the actual speeds of movement. The calculation was carried out in the «Universal Mechanism» software package. The analysis of track measuring car belts and speed gauge belts in combination with the calculation of contact pressure shows a significant overload of the inner rail even with the design parameters of the curves, not to mention the actual ones. In this regard, it is safe to say that some of the reasons for the appearance and development of rail defects are the overload of the inner rail thread caused by the discrepancy between the elevation of the outer rail and the design values, as well as the discrepancy between the actual train speeds along the section.