Study of Mechanical Damage to Metro Car Bodies With Expired Service Lifetime

The article substantiates the necessity of carrying out scientific and experimental studies to analyse mechanical damage to metro car bodies. The technical condition of the examined metro car bodies, which were operated on the tracks of the municipal enterprise «Kyiv Metro», was assessed in order to identify mechanical damage. The paper analyses the results of scientific and experimental studies of metro car bodies and frames of different series and models, which have an expired service life and have been in operation with in the period from 30 to 60 years, for the signs of mechanical damage. The bodies of metro cars of the D, E series and their modifications, as well as models Em-501, 81-502, 81-710, 81-714, 81-717, 81-714.5, 81-717.5. The objects of research were operated in different conditions: on the Sviatoshynsko-Brovarska, Obolonsko-Teremkivska, Syretsko-Pecherska lines of the Kyiv Metropolitan utility company with service in Darnytsia, Obolon, and Kharkivske electric depots, respectively. The article presents a classification of mechanical damages of car bodies depending on the place of their occurrence and criteria for excluding metro car bodies from the inventory fleet due to the presence of mechanical damages. The mechanical damages detected in the bodies and frames of metro cars operated by the municipal enterprise «Kyiv Metro» are listed. The models of metro cars with the highest number of mechanical damages are defined. It has been determined that mechanical damage to the body of a metro car depends less on its design and more on the operating conditions. Mechanical damages were recorded in the bodies of metro cars operated on the Obolonsko-Teremkivska and Syretsko-Pecherska lines of the Kyiv Metro. At the same time, there are no mechanical damages to the bodies of metro cars operating on the Sviatoshynsko-Brovarska line. The most typical types of mechanical damage to metro car bodies have been identified. In most cases, there are no mechanical damages to the bodies of the examined metro cars, and their technical condition is assessed as satisfactory, with the possibility of extending their service life and further efficient operation.