Analysis of possible wheel derailments from rolling onto contact tongue

Introduction. The research was conducted by the specialists of the Railway Research Institute in 2018–2019 on the condition of wagon wheels in operation and included an assessment of the form of wear of their working surfaces. At the same time, wheels with worn ridges of unfavorable shape were identified. In combination with other factors, such forms of wear may pose a threat to traffic safety and, in particular, wheels rolling onto contact tongue of turnout switch when moving along the point. The safe passage of a wagon is influenced by the thickness of wheel ridges and their shape, characterised by the inclination angle of ridge generatrix.
Materials and methods. The research was carried out on the basis of data on the actual geometry of wheel pairs and working surfaces of rail elements of the turnout switches. Measurements of geometric parameters of the turnout switches and the rolling surface of wagon wheels on the Russian Railways were performed using a laser profilometer.
Results. Analysis of the conditions for wheels rolling onto contact tongue of the turnout switch when moving along the point was performed and calculation scheme was defined to assess the possibility of wheel derailment due to the wheel rolling onto contact tongue. Mathematical calculations carried out on the basis of a variety of values of geometric parameters of wheel pairs and turnout switches from operation allowed to analyse their unfavorable combinations and showed that the value of the parameter of the maximum permissible inclination angle of ridges of wagon wheels should be normalised.
Discussion and conclusion. The results of dynamic strength tests and mathematical calculations show that the safe passage of wagon is influenced by wheels with ridges with inclination angle tending to 90°, and a sharp flange close to its vertex. The mutual dependence of geometric parameters in the “wheel pair — rail track” system on the turnout switches is shown. The proposals are made to normalise the maximum inclination position of the wheel ridges of wagons to ensure the safety of wheel pairs passage of turnout switches.

1. Ermolenko I. Yu. Analysis of the criteria of stability of wheel on the rail of those used during the investigations of gathering the rolling stock. Young science of Siberia. 2018;(1). URL: http://mnv.irgups.ru/toma/11-2018 (ac­ cessed 05.10.2018). (In Russ.). EDN: https://www.elibrary.ru/mzbkwl.

2. Glyuzberg B. E. Influence of the parameters of the car wheel flangeson the safety operation in turnouts. Russian Railway Science Journal. 2018;77(2):67–76. (In Russ.). https://doi.org/10.21780/2223-9731-2018-77-2-67-76. EDN: https://www.elibrary.ru/xmgddn.

3. Putrya N. N., Krysanov L. G., Teytel’ A. M., Glyuzberg B. E. et al. Turnouts. Prospects for the development of track management technology. Moscow; Transport Publ. 1976. P. 111–120. (In Russ.).

4. Krysanov L. G. Operational characteristics of wagon wheel pairs. Railway Transport. 1970;(2):58–62. (In Russ.).

5. Elsakov N. N., Radygin Yu. N. Turnouts for tracks of gauge 1520 mm. Railway Track and Facilities. 1977;(5):15–17. (In Russ.).

6. Kamenskiy V. B., Fedulov V. F., Glyuzberg B. E. New instruction. Railway Track and Facilities. 1998;(4):22–30. (In Russ.).

7. Zhelnin G. G. Specifics of the establishment of permissible speeds on the switches. Solving problems of interaction between rolling stock and ways of real outlines. Moscow; Transport Publ. 1985. P. 34–38. (In Russ.).

8. Glyuzberg B. E., Titarenko M. I., Timakova E. A., Savchenko A. A., Kuz­netsov S. V., Kalachev A. M. Dynamic ef fect on turnouts of cars having wheelsets with thin f langes. Russian Railway Science Journal. 2020;79(4):202–208. (In Russ.). https://doi.org/10.21780/2223-9731-2020-79-4-202-208. EDN: https://www.elibrary.ru/aprxey.

9. Romen Yu. S., Glyuzberg B. E., Timakova E. A., Bykov V. A. Features of mathematical modeling of dynamic processes of car passing railroad turnouts. Russian Railway Science Journal. 2020;79(3):119–126. (In Russ.). https://doi.org/10.21780/2223-9731-2020-79-3-119-126. EDN: https://www.elibrary.ru/hkjvrw.

10. Goryakina O. V., Martynenko L. V., Timakova E. A., Fofonova A. I., Shakhova N. I. Estimating the work of the technical measurements com­ plex and using innovative technologies on the East-Siberian railway. Mo­dern technologies. System analysis. Modeling. 2019;2(62):119–127. (In Russ.). https://doi.org/10.26731/1813-9108.2019.2(62).119-127. EDN: https://www.elibrary.ru/oerznz.