THEORETICAL STUDY OF THE MECHANISM OF FORMING DEFECTS ON THE ROLLING SURFACE OF WHEEL PAIRS OF THE ROLLING STOCK
Abstract and keywords
Abstract:
The study objective: To determine the physical and operational mechanisms of forming defects on the rolling surface of wheel pairs of the rolling stock, as well as to find the influence of thermal and mechanical factors that occur during braking on the formation of these defects. The task to which the paper is devoted: Theoretical study of the mechanism and causes of defects on the rolling surface of wheel pairs. Research methods: Statistic analysis of braking equipment failures according to JSC Russian Railways; theoretical analysis of thermal and mechanical processes during braking in the shoe-wheel-rail system, including phase transformations in the surface layers of steel wheels. The novelty of the work: The role of martensite transformations is found out in the surface layers of the wheel, which occur during rapid cycles of heating and cooling, as a key mechanism for forming microcracks and defects. Research results: Theoretical substantiation of the defect formation mechanism is developed, including phase and diffusion processes in the contact zone of the wheel and the shoe. Conclusions: Based on an assessment of the conditions of antiskid braking and the reliability of braking equipment, it is found out that defects in the rolling surface of wheel pairs such as slid flat and shelled tread do not always occur during train braking; jam of the wheel pair may occur as a result of intermolecular diffusion bonds after stopping the train with shoe heating, which leads to the wheel pair skidding after the train starts moving; during intensive braking, a phase transformation occurs in the subsurface layers of the wheel steel with the formation of austenite, thus the metal softened due to thermal action can partially adhere and deposit back onto the rolling surface, forming a weld-on deposit.

Keywords:
wheel pair, surface, brake system, slid flat, shelled tread, weld-on deposit
References

1. Fedorova VI, Zimakova MV, Grishaev AN. Causes of wheel defects with classification of these defects according to the responsibility of participants in the transportation process for their occurrence. Proceedings of the XV International Scientific and Technical Conference, July 13-16, 2021: Rolling Stock of the XXI century (Ideas, Requirements, Projects); St. Petersburg : FSBEI HE PGUPS; 2021.

2. Rogozin AF. Analysis of uncoupling freight cars on the railway network based on the results of the carriage industry in 2024. 2024 [cited 2025 April 30]. In: Association of Railway Equipment Manufacturers [Internet]. Available from: https://goo.su/ricnkd.

3. Karpychev VA. Development of a method for system analysis of truck brakes of rolling stock [dissertation]. [Moscow (RF)]: Moscow State University of Railway Engineering (MIIT); 2000.

4. Ministry of Internal Affairs of the USSR. General manual for the repair of braking equipment of cars 732-CV-CL [Internet]. Moscow: Transport, 1984 [cited 2025 May 20].Available from: https://files.stroyinf.ru/Data2/1/4293738/4293738248.htm

5. Korsun AA. Improving the braking characteristics of passenger rolling stock of railways [dissertation]. [Irkutsk (RF)]: Irkutsk State Transport University; 2025.

6. Krylov VI, Krylov VV. Automatic brakes of rolling stock: textbook. 4th ed. Moscow: Transport; 1983.

7. Ministry of Railways of the Russian Federation. Rules of traction calculations for train work. 1980 Aug 15.

8. Ivanov PYu, Romanovsky AI, Khamnaeva AA. Improving the efficiency of the braking system of passenger trains. Transport: Science, Technology, Management. 2020;3:39-43.

9. Ministry of Transport of the Russian Federation. Rules for the maintenance of braking equipment and brake control of railway rolling stock. 2014 June 3.

10. Petrov SYu. Patterns of processes during operation of the shoe-wheel-rail tribosystem and ways to increase its durability [dissertation]. [Moscow (RF)]: Moscow State University of Railway Engineering (MIIT); 2002.

11. Savrukhin AV, Neklyudov AN. Thermal and deformation processes in wrought wheels during extended braking. World of Transport and Transportation Journal. 2015;13(2(57)):44-49.

12. Efimov RA. Assessment of thermal loads of a wrought wheel during braking [dissertation]. [Moscow (RF)]; 2017.

13. Ivanov P, Khudonogov A, Dulskiy E. Study of the influence of the brake shoe temperature and wheel tread on braking effectiveness. Journal of Physics: Conference Series, December 10-13, 2019. Voronezh; 2020. DOIhttps://doi.org/10.1088/1742-6596/1614/1/012086.

14. Ivanov PYu, Khudonogov AM, Dulsky EYu. Study of the temperature of brake shoes with varying degrees of wear during friction braking. Herald of USURT. 2020;3(47):27-34. DOIhttps://doi.org/10.20291/2079-0392-2020-3-27-34.

15. Savrukhin AV, Neklyudov AN, Efimov RA. Simulation of the kinetics of the wheel. World of Transport and Transportation Journal. 2012;10(5(43)):42-47.

16. Zaplatin VN, Sapozhnikov YuI, Dubov AV. Fundamentals of Materials Science (metalworking): textbook for students of secondary vocational institutions. 8th ed. Moscow: Academy; 2017.

Login or Create
* Forgot password?